From ee7e5516be4f2107535ad5a3d47d9c79f93661a2 Mon Sep 17 00:00:00 2001 From: Dmitry Baryshkov Date: Sun, 29 Jun 2008 14:18:46 +0400 Subject: generic: per-device coherent dma allocator Currently x86_32, sh and cris-v32 provide per-device coherent dma memory allocator. However their implementation is nearly identical. Refactor out common code to be reused by them. Signed-off-by: Dmitry Baryshkov Signed-off-by: Ingo Molnar --- kernel/Makefile | 1 + kernel/dma-coherent.c | 127 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 128 insertions(+) create mode 100644 kernel/dma-coherent.c (limited to 'kernel') diff --git a/kernel/Makefile b/kernel/Makefile index 1c9938addb9d..9e287d8ab766 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -69,6 +69,7 @@ obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o obj-$(CONFIG_MARKERS) += marker.o obj-$(CONFIG_LATENCYTOP) += latencytop.o +obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o ifneq ($(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER),y) # According to Alan Modra , the -fno-omit-frame-pointer is diff --git a/kernel/dma-coherent.c b/kernel/dma-coherent.c new file mode 100644 index 000000000000..89a554cfd936 --- /dev/null +++ b/kernel/dma-coherent.c @@ -0,0 +1,127 @@ +/* + * Coherent per-device memory handling. + * Borrowed from i386 + */ +#include +#include + +struct dma_coherent_mem { + void *virt_base; + u32 device_base; + int size; + int flags; + unsigned long *bitmap; +}; + +int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr, + dma_addr_t device_addr, size_t size, int flags) +{ + void __iomem *mem_base = NULL; + int pages = size >> PAGE_SHIFT; + int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long); + + if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0) + goto out; + if (!size) + goto out; + if (dev->dma_mem) + goto out; + + /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */ + + mem_base = ioremap(bus_addr, size); + if (!mem_base) + goto out; + + dev->dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL); + if (!dev->dma_mem) + goto out; + dev->dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL); + if (!dev->dma_mem->bitmap) + goto free1_out; + + dev->dma_mem->virt_base = mem_base; + dev->dma_mem->device_base = device_addr; + dev->dma_mem->size = pages; + dev->dma_mem->flags = flags; + + if (flags & DMA_MEMORY_MAP) + return DMA_MEMORY_MAP; + + return DMA_MEMORY_IO; + + free1_out: + kfree(dev->dma_mem); + out: + if (mem_base) + iounmap(mem_base); + return 0; +} +EXPORT_SYMBOL(dma_declare_coherent_memory); + +void dma_release_declared_memory(struct device *dev) +{ + struct dma_coherent_mem *mem = dev->dma_mem; + + if (!mem) + return; + dev->dma_mem = NULL; + iounmap(mem->virt_base); + kfree(mem->bitmap); + kfree(mem); +} +EXPORT_SYMBOL(dma_release_declared_memory); + +void *dma_mark_declared_memory_occupied(struct device *dev, + dma_addr_t device_addr, size_t size) +{ + struct dma_coherent_mem *mem = dev->dma_mem; + int pos, err; + int pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1); + + pages >>= PAGE_SHIFT; + + if (!mem) + return ERR_PTR(-EINVAL); + + pos = (device_addr - mem->device_base) >> PAGE_SHIFT; + err = bitmap_allocate_region(mem->bitmap, pos, get_order(pages)); + if (err != 0) + return ERR_PTR(err); + return mem->virt_base + (pos << PAGE_SHIFT); +} +EXPORT_SYMBOL(dma_mark_declared_memory_occupied); + +int dma_alloc_from_coherent(struct device *dev, ssize_t size, + dma_addr_t *dma_handle, void **ret) +{ + struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL; + int order = get_order(size); + + if (mem) { + int page = bitmap_find_free_region(mem->bitmap, mem->size, + order); + if (page >= 0) { + *dma_handle = mem->device_base + (page << PAGE_SHIFT); + *ret = mem->virt_base + (page << PAGE_SHIFT); + memset(*ret, 0, size); + } + if (mem->flags & DMA_MEMORY_EXCLUSIVE) + *ret = NULL; + } + return (mem != NULL); +} + +int dma_release_from_coherent(struct device *dev, int order, void *vaddr) +{ + struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL; + + if (mem && vaddr >= mem->virt_base && vaddr < + (mem->virt_base + (mem->size << PAGE_SHIFT))) { + int page = (vaddr - mem->virt_base) >> PAGE_SHIFT; + + bitmap_release_region(mem->bitmap, page, order); + return 1; + } + return 0; +} -- cgit v1.3-18-gd494 From 538c29d43ebdac2edcef96ac07982d2296a63077 Mon Sep 17 00:00:00 2001 From: Dmitry Baryshkov Date: Fri, 18 Jul 2008 13:29:57 +0400 Subject: Generic dma-coherent: fix DMA_MEMORY_EXCLUSIVE Don't rewrite successfull allocation return values in case the memory was marked with DMA_MEMORY_EXCLUSIVE. Signed-off-by: Dmitry Baryshkov Cc: Jesse Barnes Signed-off-by: Ingo Molnar --- kernel/dma-coherent.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/dma-coherent.c b/kernel/dma-coherent.c index 89a554cfd936..56dff5cb0f29 100644 --- a/kernel/dma-coherent.c +++ b/kernel/dma-coherent.c @@ -105,8 +105,7 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size, *dma_handle = mem->device_base + (page << PAGE_SHIFT); *ret = mem->virt_base + (page << PAGE_SHIFT); memset(*ret, 0, size); - } - if (mem->flags & DMA_MEMORY_EXCLUSIVE) + } else if (mem->flags & DMA_MEMORY_EXCLUSIVE) *ret = NULL; } return (mem != NULL); -- cgit v1.3-18-gd494 From b6d4f7e3ef25beb8c658c97867d98883e69dc544 Mon Sep 17 00:00:00 2001 From: Dmitry Baryshkov Date: Sun, 20 Jul 2008 15:01:10 +0400 Subject: dma-coherent: add documentation to new interfaces Signed-off-by: Dmitry Baryshkov Cc: Jesse Barnes Signed-off-by: Ingo Molnar --- kernel/dma-coherent.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) (limited to 'kernel') diff --git a/kernel/dma-coherent.c b/kernel/dma-coherent.c index 56dff5cb0f29..7517115a8cce 100644 --- a/kernel/dma-coherent.c +++ b/kernel/dma-coherent.c @@ -92,6 +92,21 @@ void *dma_mark_declared_memory_occupied(struct device *dev, } EXPORT_SYMBOL(dma_mark_declared_memory_occupied); +/** + * Try to allocate memory from the per-device coherent area. + * + * @dev: device from which we allocate memory + * @size: size of requested memory area + * @dma_handle: This will be filled with the correct dma handle + * @ret: This pointer will be filled with the virtual address + * to allocated area. + * + * This function should be only called from per-arch %dma_alloc_coherent() + * to support allocation from per-device coherent memory pools. + * + * Returns 0 if dma_alloc_coherent should continue with allocating from + * generic memory areas, or !0 if dma_alloc_coherent should return %ret. + */ int dma_alloc_from_coherent(struct device *dev, ssize_t size, dma_addr_t *dma_handle, void **ret) { @@ -111,6 +126,19 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size, return (mem != NULL); } +/** + * Try to free the memory allocated from per-device coherent memory pool. + * @dev: device from which the memory was allocated + * @order: the order of pages allocated + * @vaddr: virtual address of allocated pages + * + * This checks whether the memory was allocated from the per-device + * coherent memory pool and if so, releases that memory. + * + * Returns 1 if we correctly released the memory, or 0 if + * %dma_release_coherent() should proceed with releasing memory from + * generic pools. + */ int dma_release_from_coherent(struct device *dev, int order, void *vaddr) { struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL; -- cgit v1.3-18-gd494 From b8d317d10cca76cabe6b03ebfeb23cc99118b731 Mon Sep 17 00:00:00 2001 From: Mike Travis Date: Thu, 24 Jul 2008 18:21:29 -0700 Subject: cpumask: make cpumask_of_cpu_map generic If an arch doesn't define cpumask_of_cpu_map, create a generic statically-initialized one for them. This allows removal of the buggy cpumask_of_cpu() macro (&cpumask_of_cpu() gives address of out-of-scope var). An arch with NR_CPUS of 4096 probably wants to allocate this itself based on the actual number of CPUs, since otherwise they're using 2MB of rodata (1024 cpus means 128k). That's what CONFIG_HAVE_CPUMASK_OF_CPU_MAP is for (only x86/64 does so at the moment). In future as we support more CPUs, we'll need to resort to a get_cpu_map()/put_cpu_map() allocation scheme. Signed-off-by: Mike Travis Signed-off-by: Rusty Russell Cc: Andrew Morton Cc: Jack Steiner Signed-off-by: Ingo Molnar --- include/linux/cpumask.h | 41 ++---------------- kernel/cpu.c | 109 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 112 insertions(+), 38 deletions(-) (limited to 'kernel') diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index 1b5c98e7fef7..8fa3b6d4a320 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -62,15 +62,7 @@ * int next_cpu_nr(cpu, mask) Next cpu past 'cpu', or nr_cpu_ids * * cpumask_t cpumask_of_cpu(cpu) Return cpumask with bit 'cpu' set - *ifdef CONFIG_HAS_CPUMASK_OF_CPU - * cpumask_of_cpu_ptr_declare(v) Declares cpumask_t *v - * cpumask_of_cpu_ptr_next(v, cpu) Sets v = &cpumask_of_cpu_map[cpu] - * cpumask_of_cpu_ptr(v, cpu) Combines above two operations - *else - * cpumask_of_cpu_ptr_declare(v) Declares cpumask_t _v and *v = &_v - * cpumask_of_cpu_ptr_next(v, cpu) Sets _v = cpumask_of_cpu(cpu) - * cpumask_of_cpu_ptr(v, cpu) Combines above two operations - *endif + * (can be used as an lvalue) * CPU_MASK_ALL Initializer - all bits set * CPU_MASK_NONE Initializer - no bits set * unsigned long *cpus_addr(mask) Array of unsigned long's in mask @@ -274,36 +266,9 @@ static inline void __cpus_shift_left(cpumask_t *dstp, } -#ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP -extern cpumask_t *cpumask_of_cpu_map; +/* cpumask_of_cpu_map[] is in kernel/cpu.c */ +extern const cpumask_t *cpumask_of_cpu_map; #define cpumask_of_cpu(cpu) (cpumask_of_cpu_map[cpu]) -#define cpumask_of_cpu_ptr(v, cpu) \ - const cpumask_t *v = &cpumask_of_cpu(cpu) -#define cpumask_of_cpu_ptr_declare(v) \ - const cpumask_t *v -#define cpumask_of_cpu_ptr_next(v, cpu) \ - v = &cpumask_of_cpu(cpu) -#else -#define cpumask_of_cpu(cpu) \ -({ \ - typeof(_unused_cpumask_arg_) m; \ - if (sizeof(m) == sizeof(unsigned long)) { \ - m.bits[0] = 1UL<<(cpu); \ - } else { \ - cpus_clear(m); \ - cpu_set((cpu), m); \ - } \ - m; \ -}) -#define cpumask_of_cpu_ptr(v, cpu) \ - cpumask_t _##v = cpumask_of_cpu(cpu); \ - const cpumask_t *v = &_##v -#define cpumask_of_cpu_ptr_declare(v) \ - cpumask_t _##v; \ - const cpumask_t *v = &_##v -#define cpumask_of_cpu_ptr_next(v, cpu) \ - _##v = cpumask_of_cpu(cpu) -#endif #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS) diff --git a/kernel/cpu.c b/kernel/cpu.c index 10ba5f1004a5..fe31ff3d3809 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -461,3 +461,112 @@ out: #endif /* CONFIG_PM_SLEEP_SMP */ #endif /* CONFIG_SMP */ + +#ifndef CONFIG_HAVE_CPUMASK_OF_CPU_MAP +/* 64 bits of zeros, for initializers. */ +#if BITS_PER_LONG == 32 +#define Z64 0, 0 +#else +#define Z64 0 +#endif + +/* Initializer macros. */ +#define CMI0(n) { .bits = { 1UL << (n) } } +#define CMI(n, ...) { .bits = { __VA_ARGS__, 1UL << ((n) % BITS_PER_LONG) } } + +#define CMI8(n, ...) \ + CMI((n), __VA_ARGS__), CMI((n)+1, __VA_ARGS__), \ + CMI((n)+2, __VA_ARGS__), CMI((n)+3, __VA_ARGS__), \ + CMI((n)+4, __VA_ARGS__), CMI((n)+5, __VA_ARGS__), \ + CMI((n)+6, __VA_ARGS__), CMI((n)+7, __VA_ARGS__) + +#if BITS_PER_LONG == 32 +#define CMI64(n, ...) \ + CMI8((n), __VA_ARGS__), CMI8((n)+8, __VA_ARGS__), \ + CMI8((n)+16, __VA_ARGS__), CMI8((n)+24, __VA_ARGS__), \ + CMI8((n)+32, 0, __VA_ARGS__), CMI8((n)+40, 0, __VA_ARGS__), \ + CMI8((n)+48, 0, __VA_ARGS__), CMI8((n)+56, 0, __VA_ARGS__) +#else +#define CMI64(n, ...) \ + CMI8((n), __VA_ARGS__), CMI8((n)+8, __VA_ARGS__), \ + CMI8((n)+16, __VA_ARGS__), CMI8((n)+24, __VA_ARGS__), \ + CMI8((n)+32, __VA_ARGS__), CMI8((n)+40, __VA_ARGS__), \ + CMI8((n)+48, __VA_ARGS__), CMI8((n)+56, __VA_ARGS__) +#endif + +#define CMI256(n, ...) \ + CMI64((n), __VA_ARGS__), CMI64((n)+64, Z64, __VA_ARGS__), \ + CMI64((n)+128, Z64, Z64, __VA_ARGS__), \ + CMI64((n)+192, Z64, Z64, Z64, __VA_ARGS__) +#define Z256 Z64, Z64, Z64, Z64 + +#define CMI1024(n, ...) \ + CMI256((n), __VA_ARGS__), \ + CMI256((n)+256, Z256, __VA_ARGS__), \ + CMI256((n)+512, Z256, Z256, __VA_ARGS__), \ + CMI256((n)+768, Z256, Z256, Z256, __VA_ARGS__) +#define Z1024 Z256, Z256, Z256, Z256 + +/* We want this statically initialized, just to be safe. We try not + * to waste too much space, either. */ +static const cpumask_t cpumask_map[] = { + CMI0(0), CMI0(1), CMI0(2), CMI0(3), +#if NR_CPUS > 4 + CMI0(4), CMI0(5), CMI0(6), CMI0(7), +#endif +#if NR_CPUS > 8 + CMI0(8), CMI0(9), CMI0(10), CMI0(11), + CMI0(12), CMI0(13), CMI0(14), CMI0(15), +#endif +#if NR_CPUS > 16 + CMI0(16), CMI0(17), CMI0(18), CMI0(19), + CMI0(20), CMI0(21), CMI0(22), CMI0(23), + CMI0(24), CMI0(25), CMI0(26), CMI0(27), + CMI0(28), CMI0(29), CMI0(30), CMI0(31), +#endif +#if NR_CPUS > 32 +#if BITS_PER_LONG == 32 + CMI(32, 0), CMI(33, 0), CMI(34, 0), CMI(35, 0), + CMI(36, 0), CMI(37, 0), CMI(38, 0), CMI(39, 0), + CMI(40, 0), CMI(41, 0), CMI(42, 0), CMI(43, 0), + CMI(44, 0), CMI(45, 0), CMI(46, 0), CMI(47, 0), + CMI(48, 0), CMI(49, 0), CMI(50, 0), CMI(51, 0), + CMI(52, 0), CMI(53, 0), CMI(54, 0), CMI(55, 0), + CMI(56, 0), CMI(57, 0), CMI(58, 0), CMI(59, 0), + CMI(60, 0), CMI(61, 0), CMI(62, 0), CMI(63, 0), +#else + CMI0(32), CMI0(33), CMI0(34), CMI0(35), + CMI0(36), CMI0(37), CMI0(38), CMI0(39), + CMI0(40), CMI0(41), CMI0(42), CMI0(43), + CMI0(44), CMI0(45), CMI0(46), CMI0(47), + CMI0(48), CMI0(49), CMI0(50), CMI0(51), + CMI0(52), CMI0(53), CMI0(54), CMI0(55), + CMI0(56), CMI0(57), CMI0(58), CMI0(59), + CMI0(60), CMI0(61), CMI0(62), CMI0(63), +#endif /* BITS_PER_LONG == 64 */ +#endif +#if NR_CPUS > 64 + CMI64(64, Z64), +#endif +#if NR_CPUS > 128 + CMI64(128, Z64, Z64), CMI64(192, Z64, Z64, Z64), +#endif +#if NR_CPUS > 256 + CMI256(256, Z256), +#endif +#if NR_CPUS > 512 + CMI256(512, Z256, Z256), CMI256(768, Z256, Z256, Z256), +#endif +#if NR_CPUS > 1024 + CMI1024(1024, Z1024), +#endif +#if NR_CPUS > 2048 + CMI1024(2048, Z1024, Z1024), CMI1024(3072, Z1024, Z1024, Z1024), +#endif +#if NR_CPUS > 4096 +#error NR_CPUS too big. Fix initializers or set CONFIG_HAVE_CPUMASK_OF_CPU_MAP +#endif +}; + +const cpumask_t *cpumask_of_cpu_map = cpumask_map; +#endif /* !CONFIG_HAVE_CPUMASK_OF_CPU_MAP */ -- cgit v1.3-18-gd494 From 6524d938b3360504b43a1278b5a8403e85383d1a Mon Sep 17 00:00:00 2001 From: Mike Travis Date: Thu, 24 Jul 2008 18:21:30 -0700 Subject: cpumask: put cpumask_of_cpu_map in the initdata section * Create the cpumask_of_cpu_map statically in the init data section using NR_CPUS but replace it during boot up with one sized by nr_cpu_ids (num possible cpus). Signed-off-by: Mike Travis Cc: Andrew Morton Cc: Jack Steiner Cc: Rusty Russell Signed-off-by: Ingo Molnar --- arch/x86/kernel/setup_percpu.c | 10 ++++++---- kernel/cpu.c | 8 +++++--- 2 files changed, 11 insertions(+), 7 deletions(-) (limited to 'kernel') diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index f7745f94c006..1cd53dfcd309 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -81,10 +81,12 @@ static void __init setup_per_cpu_maps(void) } #ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP -cpumask_t *cpumask_of_cpu_map __read_mostly; -EXPORT_SYMBOL(cpumask_of_cpu_map); - -/* requires nr_cpu_ids to be initialized */ +/* + * Replace static cpumask_of_cpu_map in the initdata section, + * with one that's allocated sized by the possible number of cpus. + * + * (requires nr_cpu_ids to be initialized) + */ static void __init setup_cpumask_of_cpu(void) { int i; diff --git a/kernel/cpu.c b/kernel/cpu.c index fe31ff3d3809..9d4e1c28c053 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -462,7 +462,6 @@ out: #endif /* CONFIG_SMP */ -#ifndef CONFIG_HAVE_CPUMASK_OF_CPU_MAP /* 64 bits of zeros, for initializers. */ #if BITS_PER_LONG == 32 #define Z64 0, 0 @@ -509,7 +508,11 @@ out: /* We want this statically initialized, just to be safe. We try not * to waste too much space, either. */ -static const cpumask_t cpumask_map[] = { +static const cpumask_t cpumask_map[] +#ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP +__initdata +#endif += { CMI0(0), CMI0(1), CMI0(2), CMI0(3), #if NR_CPUS > 4 CMI0(4), CMI0(5), CMI0(6), CMI0(7), @@ -569,4 +572,3 @@ static const cpumask_t cpumask_map[] = { }; const cpumask_t *cpumask_of_cpu_map = cpumask_map; -#endif /* !CONFIG_HAVE_CPUMASK_OF_CPU_MAP */ -- cgit v1.3-18-gd494 From 0bc3cc03fa6e1c20aecb5a33356bcaae410640b9 Mon Sep 17 00:00:00 2001 From: Mike Travis Date: Thu, 24 Jul 2008 18:21:31 -0700 Subject: cpumask: change cpumask_of_cpu_ptr to use new cpumask_of_cpu * Replace previous instances of the cpumask_of_cpu_ptr* macros with a the new (lvalue capable) generic cpumask_of_cpu(). Signed-off-by: Mike Travis Cc: Andrew Morton Cc: Jack Steiner Cc: Rusty Russell Signed-off-by: Ingo Molnar --- arch/x86/kernel/acpi/cstate.c | 3 +-- arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 10 +++------- arch/x86/kernel/cpu/cpufreq/powernow-k8.c | 15 +++++---------- arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c | 12 ++++-------- arch/x86/kernel/cpu/cpufreq/speedstep-ich.c | 3 +-- arch/x86/kernel/cpu/intel_cacheinfo.c | 3 +-- arch/x86/kernel/ldt.c | 6 ++---- arch/x86/kernel/microcode.c | 17 +++++------------ arch/x86/kernel/reboot.c | 11 +++-------- drivers/acpi/processor_throttling.c | 11 +++-------- drivers/firmware/dcdbas.c | 3 +-- drivers/misc/sgi-xp/xpc_main.c | 3 +-- kernel/stop_machine.c | 3 +-- kernel/time/tick-common.c | 8 +++----- kernel/trace/trace_sysprof.c | 4 +--- lib/smp_processor_id.c | 5 +---- net/sunrpc/svc.c | 3 +-- 17 files changed, 37 insertions(+), 83 deletions(-) (limited to 'kernel') diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c index 9220cf46aa10..c2502eb9aa83 100644 --- a/arch/x86/kernel/acpi/cstate.c +++ b/arch/x86/kernel/acpi/cstate.c @@ -73,7 +73,6 @@ int acpi_processor_ffh_cstate_probe(unsigned int cpu, struct cpuinfo_x86 *c = &cpu_data(cpu); cpumask_t saved_mask; - cpumask_of_cpu_ptr(new_mask, cpu); int retval; unsigned int eax, ebx, ecx, edx; unsigned int edx_part; @@ -92,7 +91,7 @@ int acpi_processor_ffh_cstate_probe(unsigned int cpu, /* Make sure we are running on right CPU */ saved_mask = current->cpus_allowed; - retval = set_cpus_allowed_ptr(current, new_mask); + retval = set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)); if (retval) return -1; diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c index ff2fff56f0a8..dd097b835839 100644 --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -200,12 +200,10 @@ static void drv_read(struct drv_cmd *cmd) static void drv_write(struct drv_cmd *cmd) { cpumask_t saved_mask = current->cpus_allowed; - cpumask_of_cpu_ptr_declare(cpu_mask); unsigned int i; for_each_cpu_mask_nr(i, cmd->mask) { - cpumask_of_cpu_ptr_next(cpu_mask, i); - set_cpus_allowed_ptr(current, cpu_mask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(i)); do_drv_write(cmd); } @@ -269,12 +267,11 @@ static unsigned int get_measured_perf(unsigned int cpu) } aperf_cur, mperf_cur; cpumask_t saved_mask; - cpumask_of_cpu_ptr(cpu_mask, cpu); unsigned int perf_percent; unsigned int retval; saved_mask = current->cpus_allowed; - set_cpus_allowed_ptr(current, cpu_mask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)); if (get_cpu() != cpu) { /* We were not able to run on requested processor */ put_cpu(); @@ -340,7 +337,6 @@ static unsigned int get_measured_perf(unsigned int cpu) static unsigned int get_cur_freq_on_cpu(unsigned int cpu) { - cpumask_of_cpu_ptr(cpu_mask, cpu); struct acpi_cpufreq_data *data = per_cpu(drv_data, cpu); unsigned int freq; unsigned int cached_freq; @@ -353,7 +349,7 @@ static unsigned int get_cur_freq_on_cpu(unsigned int cpu) } cached_freq = data->freq_table[data->acpi_data->state].frequency; - freq = extract_freq(get_cur_val(cpu_mask), data); + freq = extract_freq(get_cur_val(&cpumask_of_cpu(cpu)), data); if (freq != cached_freq) { /* * The dreaded BIOS frequency change behind our back. diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c index 53c7b6936973..c45ca6d4dce1 100644 --- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c +++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c @@ -479,12 +479,11 @@ static int core_voltage_post_transition(struct powernow_k8_data *data, u32 reqvi static int check_supported_cpu(unsigned int cpu) { cpumask_t oldmask; - cpumask_of_cpu_ptr(cpu_mask, cpu); u32 eax, ebx, ecx, edx; unsigned int rc = 0; oldmask = current->cpus_allowed; - set_cpus_allowed_ptr(current, cpu_mask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)); if (smp_processor_id() != cpu) { printk(KERN_ERR PFX "limiting to cpu %u failed\n", cpu); @@ -1017,7 +1016,6 @@ static int transition_frequency_pstate(struct powernow_k8_data *data, unsigned i static int powernowk8_target(struct cpufreq_policy *pol, unsigned targfreq, unsigned relation) { cpumask_t oldmask; - cpumask_of_cpu_ptr(cpu_mask, pol->cpu); struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu); u32 checkfid; u32 checkvid; @@ -1032,7 +1030,7 @@ static int powernowk8_target(struct cpufreq_policy *pol, unsigned targfreq, unsi /* only run on specific CPU from here on */ oldmask = current->cpus_allowed; - set_cpus_allowed_ptr(current, cpu_mask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(pol->cpu)); if (smp_processor_id() != pol->cpu) { printk(KERN_ERR PFX "limiting to cpu %u failed\n", pol->cpu); @@ -1107,7 +1105,6 @@ static int __cpuinit powernowk8_cpu_init(struct cpufreq_policy *pol) { struct powernow_k8_data *data; cpumask_t oldmask; - cpumask_of_cpu_ptr_declare(newmask); int rc; if (!cpu_online(pol->cpu)) @@ -1159,8 +1156,7 @@ static int __cpuinit powernowk8_cpu_init(struct cpufreq_policy *pol) /* only run on specific CPU from here on */ oldmask = current->cpus_allowed; - cpumask_of_cpu_ptr_next(newmask, pol->cpu); - set_cpus_allowed_ptr(current, newmask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(pol->cpu)); if (smp_processor_id() != pol->cpu) { printk(KERN_ERR PFX "limiting to cpu %u failed\n", pol->cpu); @@ -1182,7 +1178,7 @@ static int __cpuinit powernowk8_cpu_init(struct cpufreq_policy *pol) set_cpus_allowed_ptr(current, &oldmask); if (cpu_family == CPU_HW_PSTATE) - pol->cpus = *newmask; + pol->cpus = cpumask_of_cpu(pol->cpu); else pol->cpus = per_cpu(cpu_core_map, pol->cpu); data->available_cores = &(pol->cpus); @@ -1248,7 +1244,6 @@ static unsigned int powernowk8_get (unsigned int cpu) { struct powernow_k8_data *data; cpumask_t oldmask = current->cpus_allowed; - cpumask_of_cpu_ptr(newmask, cpu); unsigned int khz = 0; unsigned int first; @@ -1258,7 +1253,7 @@ static unsigned int powernowk8_get (unsigned int cpu) if (!data) return -EINVAL; - set_cpus_allowed_ptr(current, newmask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)); if (smp_processor_id() != cpu) { printk(KERN_ERR PFX "limiting to CPU %d failed in powernowk8_get\n", cpu); diff --git a/arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c b/arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c index ca2ac13b7af2..15e13c01cc36 100644 --- a/arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c +++ b/arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c @@ -324,10 +324,9 @@ static unsigned int get_cur_freq(unsigned int cpu) unsigned l, h; unsigned clock_freq; cpumask_t saved_mask; - cpumask_of_cpu_ptr(new_mask, cpu); saved_mask = current->cpus_allowed; - set_cpus_allowed_ptr(current, new_mask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)); if (smp_processor_id() != cpu) return 0; @@ -585,15 +584,12 @@ static int centrino_target (struct cpufreq_policy *policy, * Best effort undo.. */ - if (!cpus_empty(*covered_cpus)) { - cpumask_of_cpu_ptr_declare(new_mask); - + if (!cpus_empty(*covered_cpus)) for_each_cpu_mask_nr(j, *covered_cpus) { - cpumask_of_cpu_ptr_next(new_mask, j); - set_cpus_allowed_ptr(current, new_mask); + set_cpus_allowed_ptr(current, + &cpumask_of_cpu(j)); wrmsr(MSR_IA32_PERF_CTL, oldmsr, h); } - } tmp = freqs.new; freqs.new = freqs.old; diff --git a/arch/x86/kernel/cpu/cpufreq/speedstep-ich.c b/arch/x86/kernel/cpu/cpufreq/speedstep-ich.c index 2f3728dc24f6..191f7263c61d 100644 --- a/arch/x86/kernel/cpu/cpufreq/speedstep-ich.c +++ b/arch/x86/kernel/cpu/cpufreq/speedstep-ich.c @@ -244,8 +244,7 @@ static unsigned int _speedstep_get(const cpumask_t *cpus) static unsigned int speedstep_get(unsigned int cpu) { - cpumask_of_cpu_ptr(newmask, cpu); - return _speedstep_get(newmask); + return _speedstep_get(&cpumask_of_cpu(cpu)); } /** diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c index 650d40f7912b..6b0a10b002f1 100644 --- a/arch/x86/kernel/cpu/intel_cacheinfo.c +++ b/arch/x86/kernel/cpu/intel_cacheinfo.c @@ -516,7 +516,6 @@ static int __cpuinit detect_cache_attributes(unsigned int cpu) unsigned long j; int retval; cpumask_t oldmask; - cpumask_of_cpu_ptr(newmask, cpu); if (num_cache_leaves == 0) return -ENOENT; @@ -527,7 +526,7 @@ static int __cpuinit detect_cache_attributes(unsigned int cpu) return -ENOMEM; oldmask = current->cpus_allowed; - retval = set_cpus_allowed_ptr(current, newmask); + retval = set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)); if (retval) goto out; diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c index 3fee2aa50f3f..b68e21f06f4f 100644 --- a/arch/x86/kernel/ldt.c +++ b/arch/x86/kernel/ldt.c @@ -62,12 +62,10 @@ static int alloc_ldt(mm_context_t *pc, int mincount, int reload) if (reload) { #ifdef CONFIG_SMP - cpumask_of_cpu_ptr_declare(mask); - preempt_disable(); load_LDT(pc); - cpumask_of_cpu_ptr_next(mask, smp_processor_id()); - if (!cpus_equal(current->mm->cpu_vm_mask, *mask)) + if (!cpus_equal(current->mm->cpu_vm_mask, + cpumask_of_cpu(smp_processor_id()))) smp_call_function(flush_ldt, current->mm, 1); preempt_enable(); #else diff --git a/arch/x86/kernel/microcode.c b/arch/x86/kernel/microcode.c index 6994c751590e..652fa5c38ebe 100644 --- a/arch/x86/kernel/microcode.c +++ b/arch/x86/kernel/microcode.c @@ -388,7 +388,6 @@ static int do_microcode_update (void) void *new_mc = NULL; int cpu; cpumask_t old; - cpumask_of_cpu_ptr_declare(newmask); old = current->cpus_allowed; @@ -405,8 +404,7 @@ static int do_microcode_update (void) if (!uci->valid) continue; - cpumask_of_cpu_ptr_next(newmask, cpu); - set_cpus_allowed_ptr(current, newmask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)); error = get_maching_microcode(new_mc, cpu); if (error < 0) goto out; @@ -576,7 +574,6 @@ static int apply_microcode_check_cpu(int cpu) struct cpuinfo_x86 *c = &cpu_data(cpu); struct ucode_cpu_info *uci = ucode_cpu_info + cpu; cpumask_t old; - cpumask_of_cpu_ptr(newmask, cpu); unsigned int val[2]; int err = 0; @@ -585,7 +582,7 @@ static int apply_microcode_check_cpu(int cpu) return 0; old = current->cpus_allowed; - set_cpus_allowed_ptr(current, newmask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)); /* Check if the microcode we have in memory matches the CPU */ if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 || @@ -623,12 +620,11 @@ static int apply_microcode_check_cpu(int cpu) static void microcode_init_cpu(int cpu, int resume) { cpumask_t old; - cpumask_of_cpu_ptr(newmask, cpu); struct ucode_cpu_info *uci = ucode_cpu_info + cpu; old = current->cpus_allowed; - set_cpus_allowed_ptr(current, newmask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)); mutex_lock(µcode_mutex); collect_cpu_info(cpu); if (uci->valid && system_state == SYSTEM_RUNNING && !resume) @@ -661,13 +657,10 @@ static ssize_t reload_store(struct sys_device *dev, if (end == buf) return -EINVAL; if (val == 1) { - cpumask_t old; - cpumask_of_cpu_ptr(newmask, cpu); - - old = current->cpus_allowed; + cpumask_t old = current->cpus_allowed; get_online_cpus(); - set_cpus_allowed_ptr(current, newmask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)); mutex_lock(µcode_mutex); if (uci->valid) diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 06a9f643817e..724adfc63cb9 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -414,25 +414,20 @@ void native_machine_shutdown(void) /* The boot cpu is always logical cpu 0 */ int reboot_cpu_id = 0; - cpumask_of_cpu_ptr(newmask, reboot_cpu_id); #ifdef CONFIG_X86_32 /* See if there has been given a command line override */ if ((reboot_cpu != -1) && (reboot_cpu < NR_CPUS) && - cpu_online(reboot_cpu)) { + cpu_online(reboot_cpu)) reboot_cpu_id = reboot_cpu; - cpumask_of_cpu_ptr_next(newmask, reboot_cpu_id); - } #endif /* Make certain the cpu I'm about to reboot on is online */ - if (!cpu_online(reboot_cpu_id)) { + if (!cpu_online(reboot_cpu_id)) reboot_cpu_id = smp_processor_id(); - cpumask_of_cpu_ptr_next(newmask, reboot_cpu_id); - } /* Make certain I only run on the appropriate processor */ - set_cpus_allowed_ptr(current, newmask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(reboot_cpu_id)); /* O.K Now that I'm on the appropriate processor, * stop all of the others. diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index a2c3f9cfa549..a56fc6c4394b 100644 --- a/drivers/acpi/processor_throttling.c +++ b/drivers/acpi/processor_throttling.c @@ -827,7 +827,6 @@ static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr) static int acpi_processor_get_throttling(struct acpi_processor *pr) { cpumask_t saved_mask; - cpumask_of_cpu_ptr_declare(new_mask); int ret; if (!pr) @@ -839,8 +838,7 @@ static int acpi_processor_get_throttling(struct acpi_processor *pr) * Migrate task to the cpu pointed by pr. */ saved_mask = current->cpus_allowed; - cpumask_of_cpu_ptr_next(new_mask, pr->id); - set_cpus_allowed_ptr(current, new_mask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(pr->id)); ret = pr->throttling.acpi_processor_get_throttling(pr); /* restore the previous state */ set_cpus_allowed_ptr(current, &saved_mask); @@ -989,7 +987,6 @@ static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr, int acpi_processor_set_throttling(struct acpi_processor *pr, int state) { cpumask_t saved_mask; - cpumask_of_cpu_ptr_declare(new_mask); int ret = 0; unsigned int i; struct acpi_processor *match_pr; @@ -1028,8 +1025,7 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state) * it can be called only for the cpu pointed by pr. */ if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) { - cpumask_of_cpu_ptr_next(new_mask, pr->id); - set_cpus_allowed_ptr(current, new_mask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(pr->id)); ret = p_throttling->acpi_processor_set_throttling(pr, t_state.target_state); } else { @@ -1060,8 +1056,7 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state) continue; } t_state.cpu = i; - cpumask_of_cpu_ptr_next(new_mask, i); - set_cpus_allowed_ptr(current, new_mask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(i)); ret = match_pr->throttling. acpi_processor_set_throttling( match_pr, t_state.target_state); diff --git a/drivers/firmware/dcdbas.c b/drivers/firmware/dcdbas.c index c66817e7717b..50a071f1c945 100644 --- a/drivers/firmware/dcdbas.c +++ b/drivers/firmware/dcdbas.c @@ -245,7 +245,6 @@ static ssize_t host_control_on_shutdown_store(struct device *dev, static int smi_request(struct smi_cmd *smi_cmd) { cpumask_t old_mask; - cpumask_of_cpu_ptr(new_mask, 0); int ret = 0; if (smi_cmd->magic != SMI_CMD_MAGIC) { @@ -256,7 +255,7 @@ static int smi_request(struct smi_cmd *smi_cmd) /* SMI requires CPU 0 */ old_mask = current->cpus_allowed; - set_cpus_allowed_ptr(current, new_mask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(0)); if (smp_processor_id() != 0) { dev_dbg(&dcdbas_pdev->dev, "%s: failed to get CPU 0\n", __func__); diff --git a/drivers/misc/sgi-xp/xpc_main.c b/drivers/misc/sgi-xp/xpc_main.c index 579b01ff82d4..c3b4227f48a5 100644 --- a/drivers/misc/sgi-xp/xpc_main.c +++ b/drivers/misc/sgi-xp/xpc_main.c @@ -229,11 +229,10 @@ xpc_hb_checker(void *ignore) int last_IRQ_count = 0; int new_IRQ_count; int force_IRQ = 0; - cpumask_of_cpu_ptr(cpumask, XPC_HB_CHECK_CPU); /* this thread was marked active by xpc_hb_init() */ - set_cpus_allowed_ptr(current, cpumask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(XPC_HB_CHECK_CPU)); /* set our heartbeating to other partitions into motion */ xpc_hb_check_timeout = jiffies + (xpc_hb_check_interval * HZ); diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 738b411ff2d3..ba9b2054ecbd 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -33,9 +33,8 @@ static int stopmachine(void *cpu) { int irqs_disabled = 0; int prepared = 0; - cpumask_of_cpu_ptr(cpumask, (int)(long)cpu); - set_cpus_allowed_ptr(current, cpumask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu((int)(long)cpu)); /* Ack: we are alive */ smp_mb(); /* Theoretically the ack = 0 might not be on this CPU yet. */ diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index bf43284d6855..80c4336f4188 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -196,12 +196,10 @@ static int tick_check_new_device(struct clock_event_device *newdev) struct tick_device *td; int cpu, ret = NOTIFY_OK; unsigned long flags; - cpumask_of_cpu_ptr_declare(cpumask); spin_lock_irqsave(&tick_device_lock, flags); cpu = smp_processor_id(); - cpumask_of_cpu_ptr_next(cpumask, cpu); if (!cpu_isset(cpu, newdev->cpumask)) goto out_bc; @@ -209,7 +207,7 @@ static int tick_check_new_device(struct clock_event_device *newdev) curdev = td->evtdev; /* cpu local device ? */ - if (!cpus_equal(newdev->cpumask, *cpumask)) { + if (!cpus_equal(newdev->cpumask, cpumask_of_cpu(cpu))) { /* * If the cpu affinity of the device interrupt can not @@ -222,7 +220,7 @@ static int tick_check_new_device(struct clock_event_device *newdev) * If we have a cpu local device already, do not replace it * by a non cpu local device */ - if (curdev && cpus_equal(curdev->cpumask, *cpumask)) + if (curdev && cpus_equal(curdev->cpumask, cpumask_of_cpu(cpu))) goto out_bc; } @@ -254,7 +252,7 @@ static int tick_check_new_device(struct clock_event_device *newdev) curdev = NULL; } clockevents_exchange_device(curdev, newdev); - tick_setup_device(td, newdev, cpu, cpumask); + tick_setup_device(td, newdev, cpu, &cpumask_of_cpu(cpu)); if (newdev->features & CLOCK_EVT_FEAT_ONESHOT) tick_oneshot_notify(); diff --git a/kernel/trace/trace_sysprof.c b/kernel/trace/trace_sysprof.c index ce2d723c10e1..bb948e52ce20 100644 --- a/kernel/trace/trace_sysprof.c +++ b/kernel/trace/trace_sysprof.c @@ -213,9 +213,7 @@ static void start_stack_timers(void) int cpu; for_each_online_cpu(cpu) { - cpumask_of_cpu_ptr(new_mask, cpu); - - set_cpus_allowed_ptr(current, new_mask); + set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)); start_stack_timer(cpu); } set_cpus_allowed_ptr(current, &saved_mask); diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c index c4381d9516f6..0f8fc22ed103 100644 --- a/lib/smp_processor_id.c +++ b/lib/smp_processor_id.c @@ -11,7 +11,6 @@ notrace unsigned int debug_smp_processor_id(void) { unsigned long preempt_count = preempt_count(); int this_cpu = raw_smp_processor_id(); - cpumask_of_cpu_ptr_declare(this_mask); if (likely(preempt_count)) goto out; @@ -23,9 +22,7 @@ notrace unsigned int debug_smp_processor_id(void) * Kernel threads bound to a single CPU can safely use * smp_processor_id(): */ - cpumask_of_cpu_ptr_next(this_mask, this_cpu); - - if (cpus_equal(current->cpus_allowed, *this_mask)) + if (cpus_equal(current->cpus_allowed, cpumask_of_cpu(this_cpu))) goto out; /* diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 835d27413083..5a32cb7c4bb4 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -310,8 +310,7 @@ svc_pool_map_set_cpumask(struct task_struct *task, unsigned int pidx) switch (m->mode) { case SVC_POOL_PERCPU: { - cpumask_of_cpu_ptr(cpumask, node); - set_cpus_allowed_ptr(task, cpumask); + set_cpus_allowed_ptr(task, &cpumask_of_cpu(node)); break; } case SVC_POOL_PERNODE: -- cgit v1.3-18-gd494 From 5a7a201c51c324876d00a54e7208af6af12d1ca4 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Sat, 26 Jul 2008 16:50:47 +0200 Subject: cpumask: export cpumask_of_cpu_map fix: ERROR: "cpumask_of_cpu_map" [drivers/acpi/processor.ko] undefined! ERROR: "cpumask_of_cpu_map" [arch/x86/kernel/microcode.ko] undefined! ERROR: "cpumask_of_cpu_map" [arch/x86/kernel/cpu/cpufreq/speedstep-ich.ko] undefined! ERROR: "cpumask_of_cpu_map" [arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.ko] undefined! Signed-off-by: Ingo Molnar --- kernel/cpu.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel') diff --git a/kernel/cpu.c b/kernel/cpu.c index 9d4e1c28c053..a35d8995dc8c 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -572,3 +572,5 @@ __initdata }; const cpumask_t *cpumask_of_cpu_map = cpumask_map; + +EXPORT_SYMBOL_GPL(cpumask_of_cpu_map); -- cgit v1.3-18-gd494 From bfbcf034798b2ca45338cee5049b5694b7ddc865 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 27 Jul 2008 06:31:22 +0100 Subject: lost sysctl fix try_attach() should walk into the matching subdirectory, not the first one... Signed-off-by: Al Viro Tested-by: Valdis.Kletnieks@vt.edu Tested-by: Ingo Molnar Signed-off-by: Linus Torvalds --- kernel/sysctl.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'kernel') diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 911d846f0503..fe4713347275 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1680,43 +1680,45 @@ static __init int sysctl_init(void) core_initcall(sysctl_init); -static int is_branch_in(struct ctl_table *branch, struct ctl_table *table) +static struct ctl_table *is_branch_in(struct ctl_table *branch, + struct ctl_table *table) { struct ctl_table *p; const char *s = branch->procname; /* branch should have named subdirectory as its first element */ if (!s || !branch->child) - return 0; + return NULL; /* ... and nothing else */ if (branch[1].procname || branch[1].ctl_name) - return 0; + return NULL; /* table should contain subdirectory with the same name */ for (p = table; p->procname || p->ctl_name; p++) { if (!p->child) continue; if (p->procname && strcmp(p->procname, s) == 0) - return 1; + return p; } - return 0; + return NULL; } /* see if attaching q to p would be an improvement */ static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q) { struct ctl_table *to = p->ctl_table, *by = q->ctl_table; + struct ctl_table *next; int is_better = 0; int not_in_parent = !p->attached_by; - while (is_branch_in(by, to)) { + while ((next = is_branch_in(by, to)) != NULL) { if (by == q->attached_by) is_better = 1; if (to == p->attached_by) not_in_parent = 1; by = by->child; - to = to->child; + to = next->child; } if (is_better && not_in_parent) { -- cgit v1.3-18-gd494 From 605ccb73f6a1c891a16268b3a2923208fc637958 Mon Sep 17 00:00:00 2001 From: Andrea Righi Date: Sun, 27 Jul 2008 13:39:03 +0200 Subject: tracing: remove unused variable MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Remove the following warning with CONFIG_TRACING=y: kernel/trace/trace.c: In function ‘s_next’: kernel/trace/trace.c:1186: warning: unused variable ‘last_ent’ Signed-off-by: Andrea Righi Signed-off-by: Linus Torvalds --- kernel/trace/trace.c | 1 - 1 file changed, 1 deletion(-) (limited to 'kernel') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index fc20e09a6cb1..8f3fb3db61c3 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1183,7 +1183,6 @@ static void *find_next_entry_inc(struct trace_iterator *iter) static void *s_next(struct seq_file *m, void *v, loff_t *pos) { struct trace_iterator *iter = m->private; - void *last_ent = iter->ent; int i = (int)*pos; void *ent; -- cgit v1.3-18-gd494 From 5995477ab7f3522c497c9c4a1c55373e9d655574 Mon Sep 17 00:00:00 2001 From: Andrea Righi Date: Sun, 27 Jul 2008 17:29:15 +0200 Subject: task IO accounting: improve code readability Put all i/o statistics in struct proc_io_accounting and use inline functions to initialize and increment statistics, removing a lot of single variable assignments. This also reduces the kernel size as following (with CONFIG_TASK_XACCT=y and CONFIG_TASK_IO_ACCOUNTING=y). text data bss dec hex filename 11651 0 0 11651 2d83 kernel/exit.o.before 11619 0 0 11619 2d63 kernel/exit.o.after 10886 132 136 11154 2b92 kernel/fork.o.before 10758 132 136 11026 2b12 kernel/fork.o.after 3082029 807968 4818600 8708597 84e1f5 vmlinux.o.before 3081869 807968 4818600 8708437 84e155 vmlinux.o.after Signed-off-by: Andrea Righi Acked-by: Oleg Nesterov Signed-off-by: Linus Torvalds --- fs/proc/base.c | 57 ++++++++++------------------------ include/linux/sched.h | 19 ++++-------- include/linux/task_io_accounting.h | 27 ++++++++++++++-- include/linux/task_io_accounting_ops.h | 56 +++++++++++++++++++++++++++------ kernel/exit.c | 30 ++---------------- kernel/fork.c | 15 ++------- kernel/tsacct.c | 14 ++++----- 7 files changed, 104 insertions(+), 114 deletions(-) (limited to 'kernel') diff --git a/fs/proc/base.c b/fs/proc/base.c index e74308bdabd3..3d94906c7aa8 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -53,6 +53,7 @@ #include #include #include +#include #include #include #include @@ -2402,44 +2403,17 @@ static int proc_base_fill_cache(struct file *filp, void *dirent, #ifdef CONFIG_TASK_IO_ACCOUNTING static int do_io_accounting(struct task_struct *task, char *buffer, int whole) { - u64 rchar, wchar, syscr, syscw; - struct task_io_accounting ioac; - - rchar = task->rchar; - wchar = task->wchar; - syscr = task->syscr; - syscw = task->syscw; - memcpy(&ioac, &task->ioac, sizeof(ioac)); - - if (whole) { - unsigned long flags; - - if (lock_task_sighand(task, &flags)) { - struct signal_struct *sig = task->signal; - struct task_struct *t = task; - - rchar += sig->rchar; - wchar += sig->wchar; - syscr += sig->syscr; - syscw += sig->syscw; - - ioac.read_bytes += sig->ioac.read_bytes; - ioac.write_bytes += sig->ioac.write_bytes; - ioac.cancelled_write_bytes += - sig->ioac.cancelled_write_bytes; - while_each_thread(task, t) { - rchar += t->rchar; - wchar += t->wchar; - syscr += t->syscr; - syscw += t->syscw; - - ioac.read_bytes += t->ioac.read_bytes; - ioac.write_bytes += t->ioac.write_bytes; - ioac.cancelled_write_bytes += - t->ioac.cancelled_write_bytes; - } - unlock_task_sighand(task, &flags); - } + struct proc_io_accounting acct = task->ioac; + unsigned long flags; + + if (whole && lock_task_sighand(task, &flags)) { + struct task_struct *t = task; + + task_io_accounting_add(&acct, &task->signal->ioac); + while_each_thread(task, t) + task_io_accounting_add(&acct, &t->ioac); + + unlock_task_sighand(task, &flags); } return sprintf(buffer, "rchar: %llu\n" @@ -2449,9 +2423,10 @@ static int do_io_accounting(struct task_struct *task, char *buffer, int whole) "read_bytes: %llu\n" "write_bytes: %llu\n" "cancelled_write_bytes: %llu\n", - rchar, wchar, syscr, syscw, - ioac.read_bytes, ioac.write_bytes, - ioac.cancelled_write_bytes); + acct.chr.rchar, acct.chr.wchar, + acct.chr.syscr, acct.chr.syscw, + acct.blk.read_bytes, acct.blk.write_bytes, + acct.blk.cancelled_write_bytes); } static int proc_tid_io_accounting(struct task_struct *task, char *buffer) diff --git a/include/linux/sched.h b/include/linux/sched.h index f59318a0099b..034c1ca6b332 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -505,10 +505,7 @@ struct signal_struct { unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; unsigned long inblock, oublock, cinblock, coublock; -#ifdef CONFIG_TASK_XACCT - u64 rchar, wchar, syscr, syscw; -#endif - struct task_io_accounting ioac; + struct proc_io_accounting ioac; /* * Cumulative ns of scheduled CPU time for dead threads in the @@ -1256,11 +1253,7 @@ struct task_struct { unsigned long ptrace_message; siginfo_t *last_siginfo; /* For ptrace use. */ -#ifdef CONFIG_TASK_XACCT -/* i/o counters(bytes read/written, #syscalls */ - u64 rchar, wchar, syscr, syscw; -#endif - struct task_io_accounting ioac; + struct proc_io_accounting ioac; #if defined(CONFIG_TASK_XACCT) u64 acct_rss_mem1; /* accumulated rss usage */ u64 acct_vm_mem1; /* accumulated virtual memory usage */ @@ -2190,22 +2183,22 @@ extern long sched_group_rt_period(struct task_group *tg); #ifdef CONFIG_TASK_XACCT static inline void add_rchar(struct task_struct *tsk, ssize_t amt) { - tsk->rchar += amt; + tsk->ioac.chr.rchar += amt; } static inline void add_wchar(struct task_struct *tsk, ssize_t amt) { - tsk->wchar += amt; + tsk->ioac.chr.wchar += amt; } static inline void inc_syscr(struct task_struct *tsk) { - tsk->syscr++; + tsk->ioac.chr.syscr++; } static inline void inc_syscw(struct task_struct *tsk) { - tsk->syscw++; + tsk->ioac.chr.syscw++; } #else static inline void add_rchar(struct task_struct *tsk, ssize_t amt) diff --git a/include/linux/task_io_accounting.h b/include/linux/task_io_accounting.h index 44d00e9cceea..165390f8b936 100644 --- a/include/linux/task_io_accounting.h +++ b/include/linux/task_io_accounting.h @@ -1,5 +1,5 @@ /* - * task_io_accounting: a structure which is used for recording a single task's + * proc_io_accounting: a structure which is used for recording a single task's * IO statistics. * * Don't include this header file directly - it is designed to be dragged in via @@ -8,6 +8,22 @@ * Blame akpm@osdl.org for all this. */ +#ifdef CONFIG_TASK_XACCT +struct task_chr_io_accounting { + /* bytes read */ + u64 rchar; + /* bytes written */ + u64 wchar; + /* # of read syscalls */ + u64 syscr; + /* # of write syscalls */ + u64 syscw; +}; +#else /* CONFIG_TASK_XACCT */ +struct task_chr_io_accounting { +}; +#endif /* CONFIG_TASK_XACCT */ + #ifdef CONFIG_TASK_IO_ACCOUNTING struct task_io_accounting { /* @@ -31,7 +47,12 @@ struct task_io_accounting { */ u64 cancelled_write_bytes; }; -#else +#else /* CONFIG_TASK_IO_ACCOUNTING */ struct task_io_accounting { }; -#endif +#endif /* CONFIG_TASK_IO_ACCOUNTING */ + +struct proc_io_accounting { + struct task_chr_io_accounting chr; + struct task_io_accounting blk; +}; diff --git a/include/linux/task_io_accounting_ops.h b/include/linux/task_io_accounting_ops.h index ff46c6fad79d..e6f958ebe97f 100644 --- a/include/linux/task_io_accounting_ops.h +++ b/include/linux/task_io_accounting_ops.h @@ -9,7 +9,7 @@ #ifdef CONFIG_TASK_IO_ACCOUNTING static inline void task_io_account_read(size_t bytes) { - current->ioac.read_bytes += bytes; + current->ioac.blk.read_bytes += bytes; } /* @@ -18,12 +18,12 @@ static inline void task_io_account_read(size_t bytes) */ static inline unsigned long task_io_get_inblock(const struct task_struct *p) { - return p->ioac.read_bytes >> 9; + return p->ioac.blk.read_bytes >> 9; } static inline void task_io_account_write(size_t bytes) { - current->ioac.write_bytes += bytes; + current->ioac.blk.write_bytes += bytes; } /* @@ -32,17 +32,25 @@ static inline void task_io_account_write(size_t bytes) */ static inline unsigned long task_io_get_oublock(const struct task_struct *p) { - return p->ioac.write_bytes >> 9; + return p->ioac.blk.write_bytes >> 9; } static inline void task_io_account_cancelled_write(size_t bytes) { - current->ioac.cancelled_write_bytes += bytes; + current->ioac.blk.cancelled_write_bytes += bytes; } -static inline void task_io_accounting_init(struct task_struct *tsk) +static inline void task_io_accounting_init(struct proc_io_accounting *ioac) { - memset(&tsk->ioac, 0, sizeof(tsk->ioac)); + memset(ioac, 0, sizeof(*ioac)); +} + +static inline void task_blk_io_accounting_add(struct proc_io_accounting *dst, + struct proc_io_accounting *src) +{ + dst->blk.read_bytes += src->blk.read_bytes; + dst->blk.write_bytes += src->blk.write_bytes; + dst->blk.cancelled_write_bytes += src->blk.cancelled_write_bytes; } #else @@ -69,9 +77,37 @@ static inline void task_io_account_cancelled_write(size_t bytes) { } -static inline void task_io_accounting_init(struct task_struct *tsk) +static inline void task_io_accounting_init(struct proc_io_accounting *ioac) +{ +} + +static inline void task_blk_io_accounting_add(struct proc_io_accounting *dst, + struct proc_io_accounting *src) { } -#endif /* CONFIG_TASK_IO_ACCOUNTING */ -#endif /* __TASK_IO_ACCOUNTING_OPS_INCLUDED */ +#endif /* CONFIG_TASK_IO_ACCOUNTING */ + +#ifdef CONFIG_TASK_XACCT +static inline void task_chr_io_accounting_add(struct proc_io_accounting *dst, + struct proc_io_accounting *src) +{ + dst->chr.rchar += src->chr.rchar; + dst->chr.wchar += src->chr.wchar; + dst->chr.syscr += src->chr.syscr; + dst->chr.syscw += src->chr.syscw; +} +#else +static inline void task_chr_io_accounting_add(struct proc_io_accounting *dst, + struct proc_io_accounting *src) +{ +} +#endif /* CONFIG_TASK_XACCT */ + +static inline void task_io_accounting_add(struct proc_io_accounting *dst, + struct proc_io_accounting *src) +{ + task_chr_io_accounting_add(dst, src); + task_blk_io_accounting_add(dst, src); +} +#endif /* __TASK_IO_ACCOUNTING_OPS_INCLUDED */ diff --git a/kernel/exit.c b/kernel/exit.c index 0caf590548a0..eb4d6470d1d0 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -121,18 +121,7 @@ static void __exit_signal(struct task_struct *tsk) sig->nivcsw += tsk->nivcsw; sig->inblock += task_io_get_inblock(tsk); sig->oublock += task_io_get_oublock(tsk); -#ifdef CONFIG_TASK_XACCT - sig->rchar += tsk->rchar; - sig->wchar += tsk->wchar; - sig->syscr += tsk->syscr; - sig->syscw += tsk->syscw; -#endif /* CONFIG_TASK_XACCT */ -#ifdef CONFIG_TASK_IO_ACCOUNTING - sig->ioac.read_bytes += tsk->ioac.read_bytes; - sig->ioac.write_bytes += tsk->ioac.write_bytes; - sig->ioac.cancelled_write_bytes += - tsk->ioac.cancelled_write_bytes; -#endif /* CONFIG_TASK_IO_ACCOUNTING */ + task_io_accounting_add(&sig->ioac, &tsk->ioac); sig->sum_sched_runtime += tsk->se.sum_exec_runtime; sig = NULL; /* Marker for below. */ } @@ -1363,21 +1352,8 @@ static int wait_task_zombie(struct task_struct *p, int options, psig->coublock += task_io_get_oublock(p) + sig->oublock + sig->coublock; -#ifdef CONFIG_TASK_XACCT - psig->rchar += p->rchar + sig->rchar; - psig->wchar += p->wchar + sig->wchar; - psig->syscr += p->syscr + sig->syscr; - psig->syscw += p->syscw + sig->syscw; -#endif /* CONFIG_TASK_XACCT */ -#ifdef CONFIG_TASK_IO_ACCOUNTING - psig->ioac.read_bytes += - p->ioac.read_bytes + sig->ioac.read_bytes; - psig->ioac.write_bytes += - p->ioac.write_bytes + sig->ioac.write_bytes; - psig->ioac.cancelled_write_bytes += - p->ioac.cancelled_write_bytes + - sig->ioac.cancelled_write_bytes; -#endif /* CONFIG_TASK_IO_ACCOUNTING */ + task_io_accounting_add(&psig->ioac, &p->ioac); + task_io_accounting_add(&psig->ioac, &sig->ioac); spin_unlock_irq(&p->parent->sighand->siglock); } diff --git a/kernel/fork.c b/kernel/fork.c index 5e050c1317c4..8214ba7c8bb1 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -806,12 +806,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk) sig->nvcsw = sig->nivcsw = sig->cnvcsw = sig->cnivcsw = 0; sig->min_flt = sig->maj_flt = sig->cmin_flt = sig->cmaj_flt = 0; sig->inblock = sig->oublock = sig->cinblock = sig->coublock = 0; -#ifdef CONFIG_TASK_XACCT - sig->rchar = sig->wchar = sig->syscr = sig->syscw = 0; -#endif -#ifdef CONFIG_TASK_IO_ACCOUNTING - memset(&sig->ioac, 0, sizeof(sig->ioac)); -#endif + task_io_accounting_init(&sig->ioac); sig->sum_sched_runtime = 0; INIT_LIST_HEAD(&sig->cpu_timers[0]); INIT_LIST_HEAD(&sig->cpu_timers[1]); @@ -994,13 +989,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->last_switch_timestamp = 0; #endif -#ifdef CONFIG_TASK_XACCT - p->rchar = 0; /* I/O counter: bytes read */ - p->wchar = 0; /* I/O counter: bytes written */ - p->syscr = 0; /* I/O counter: read syscalls */ - p->syscw = 0; /* I/O counter: write syscalls */ -#endif - task_io_accounting_init(p); + task_io_accounting_init(&p->ioac); acct_clear_integrals(p); p->it_virt_expires = cputime_zero; diff --git a/kernel/tsacct.c b/kernel/tsacct.c index 3da47ccdc5e5..f9cd2561689c 100644 --- a/kernel/tsacct.c +++ b/kernel/tsacct.c @@ -94,14 +94,14 @@ void xacct_add_tsk(struct taskstats *stats, struct task_struct *p) stats->hiwater_vm = mm->hiwater_vm * PAGE_SIZE / KB; mmput(mm); } - stats->read_char = p->rchar; - stats->write_char = p->wchar; - stats->read_syscalls = p->syscr; - stats->write_syscalls = p->syscw; + stats->read_char = p->ioac.chr.rchar; + stats->write_char = p->ioac.chr.wchar; + stats->read_syscalls = p->ioac.chr.syscr; + stats->write_syscalls = p->ioac.chr.syscw; #ifdef CONFIG_TASK_IO_ACCOUNTING - stats->read_bytes = p->ioac.read_bytes; - stats->write_bytes = p->ioac.write_bytes; - stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes; + stats->read_bytes = p->ioac.blk.read_bytes; + stats->write_bytes = p->ioac.blk.write_bytes; + stats->cancelled_write_bytes = p->ioac.blk.cancelled_write_bytes; #else stats->read_bytes = 0; stats->write_bytes = 0; -- cgit v1.3-18-gd494 From 940389b8afad6495211614c13eb91ef7001773ec Mon Sep 17 00:00:00 2001 From: Andrea Righi Date: Mon, 28 Jul 2008 00:48:12 +0200 Subject: task IO accounting: move all IO statistics in struct task_io_accounting Simplify the code of include/linux/task_io_accounting.h. It is also more reasonable to have all the task i/o-related statistics in a single struct (task_io_accounting). Signed-off-by: Andrea Righi Signed-off-by: Oleg Nesterov Signed-off-by: Linus Torvalds --- fs/proc/base.c | 10 +++---- include/linux/sched.h | 12 ++++----- include/linux/task_io_accounting.h | 17 ++---------- include/linux/task_io_accounting_ops.h | 48 +++++++++++++++++----------------- kernel/tsacct.c | 14 +++++----- 5 files changed, 44 insertions(+), 57 deletions(-) (limited to 'kernel') diff --git a/fs/proc/base.c b/fs/proc/base.c index 3d94906c7aa8..01ed610f9b87 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2403,7 +2403,7 @@ static int proc_base_fill_cache(struct file *filp, void *dirent, #ifdef CONFIG_TASK_IO_ACCOUNTING static int do_io_accounting(struct task_struct *task, char *buffer, int whole) { - struct proc_io_accounting acct = task->ioac; + struct task_io_accounting acct = task->ioac; unsigned long flags; if (whole && lock_task_sighand(task, &flags)) { @@ -2423,10 +2423,10 @@ static int do_io_accounting(struct task_struct *task, char *buffer, int whole) "read_bytes: %llu\n" "write_bytes: %llu\n" "cancelled_write_bytes: %llu\n", - acct.chr.rchar, acct.chr.wchar, - acct.chr.syscr, acct.chr.syscw, - acct.blk.read_bytes, acct.blk.write_bytes, - acct.blk.cancelled_write_bytes); + acct.rchar, acct.wchar, + acct.syscr, acct.syscw, + acct.read_bytes, acct.write_bytes, + acct.cancelled_write_bytes); } static int proc_tid_io_accounting(struct task_struct *task, char *buffer) diff --git a/include/linux/sched.h b/include/linux/sched.h index 034c1ca6b332..5270d449ff9d 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -505,7 +505,7 @@ struct signal_struct { unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; unsigned long inblock, oublock, cinblock, coublock; - struct proc_io_accounting ioac; + struct task_io_accounting ioac; /* * Cumulative ns of scheduled CPU time for dead threads in the @@ -1253,7 +1253,7 @@ struct task_struct { unsigned long ptrace_message; siginfo_t *last_siginfo; /* For ptrace use. */ - struct proc_io_accounting ioac; + struct task_io_accounting ioac; #if defined(CONFIG_TASK_XACCT) u64 acct_rss_mem1; /* accumulated rss usage */ u64 acct_vm_mem1; /* accumulated virtual memory usage */ @@ -2183,22 +2183,22 @@ extern long sched_group_rt_period(struct task_group *tg); #ifdef CONFIG_TASK_XACCT static inline void add_rchar(struct task_struct *tsk, ssize_t amt) { - tsk->ioac.chr.rchar += amt; + tsk->ioac.rchar += amt; } static inline void add_wchar(struct task_struct *tsk, ssize_t amt) { - tsk->ioac.chr.wchar += amt; + tsk->ioac.wchar += amt; } static inline void inc_syscr(struct task_struct *tsk) { - tsk->ioac.chr.syscr++; + tsk->ioac.syscr++; } static inline void inc_syscw(struct task_struct *tsk) { - tsk->ioac.chr.syscw++; + tsk->ioac.syscw++; } #else static inline void add_rchar(struct task_struct *tsk, ssize_t amt) diff --git a/include/linux/task_io_accounting.h b/include/linux/task_io_accounting.h index 165390f8b936..5e88afc9a2fb 100644 --- a/include/linux/task_io_accounting.h +++ b/include/linux/task_io_accounting.h @@ -1,5 +1,5 @@ /* - * proc_io_accounting: a structure which is used for recording a single task's + * task_io_accounting: a structure which is used for recording a single task's * IO statistics. * * Don't include this header file directly - it is designed to be dragged in via @@ -8,8 +8,8 @@ * Blame akpm@osdl.org for all this. */ +struct task_io_accounting { #ifdef CONFIG_TASK_XACCT -struct task_chr_io_accounting { /* bytes read */ u64 rchar; /* bytes written */ @@ -18,14 +18,9 @@ struct task_chr_io_accounting { u64 syscr; /* # of write syscalls */ u64 syscw; -}; -#else /* CONFIG_TASK_XACCT */ -struct task_chr_io_accounting { -}; #endif /* CONFIG_TASK_XACCT */ #ifdef CONFIG_TASK_IO_ACCOUNTING -struct task_io_accounting { /* * The number of bytes which this task has caused to be read from * storage. @@ -46,13 +41,5 @@ struct task_io_accounting { * information loss in doing that. */ u64 cancelled_write_bytes; -}; -#else /* CONFIG_TASK_IO_ACCOUNTING */ -struct task_io_accounting { -}; #endif /* CONFIG_TASK_IO_ACCOUNTING */ - -struct proc_io_accounting { - struct task_chr_io_accounting chr; - struct task_io_accounting blk; }; diff --git a/include/linux/task_io_accounting_ops.h b/include/linux/task_io_accounting_ops.h index e6f958ebe97f..4d090f9ee608 100644 --- a/include/linux/task_io_accounting_ops.h +++ b/include/linux/task_io_accounting_ops.h @@ -9,7 +9,7 @@ #ifdef CONFIG_TASK_IO_ACCOUNTING static inline void task_io_account_read(size_t bytes) { - current->ioac.blk.read_bytes += bytes; + current->ioac.read_bytes += bytes; } /* @@ -18,12 +18,12 @@ static inline void task_io_account_read(size_t bytes) */ static inline unsigned long task_io_get_inblock(const struct task_struct *p) { - return p->ioac.blk.read_bytes >> 9; + return p->ioac.read_bytes >> 9; } static inline void task_io_account_write(size_t bytes) { - current->ioac.blk.write_bytes += bytes; + current->ioac.write_bytes += bytes; } /* @@ -32,25 +32,25 @@ static inline void task_io_account_write(size_t bytes) */ static inline unsigned long task_io_get_oublock(const struct task_struct *p) { - return p->ioac.blk.write_bytes >> 9; + return p->ioac.write_bytes >> 9; } static inline void task_io_account_cancelled_write(size_t bytes) { - current->ioac.blk.cancelled_write_bytes += bytes; + current->ioac.cancelled_write_bytes += bytes; } -static inline void task_io_accounting_init(struct proc_io_accounting *ioac) +static inline void task_io_accounting_init(struct task_io_accounting *ioac) { memset(ioac, 0, sizeof(*ioac)); } -static inline void task_blk_io_accounting_add(struct proc_io_accounting *dst, - struct proc_io_accounting *src) +static inline void task_blk_io_accounting_add(struct task_io_accounting *dst, + struct task_io_accounting *src) { - dst->blk.read_bytes += src->blk.read_bytes; - dst->blk.write_bytes += src->blk.write_bytes; - dst->blk.cancelled_write_bytes += src->blk.cancelled_write_bytes; + dst->read_bytes += src->read_bytes; + dst->write_bytes += src->write_bytes; + dst->cancelled_write_bytes += src->cancelled_write_bytes; } #else @@ -77,35 +77,35 @@ static inline void task_io_account_cancelled_write(size_t bytes) { } -static inline void task_io_accounting_init(struct proc_io_accounting *ioac) +static inline void task_io_accounting_init(struct task_io_accounting *ioac) { } -static inline void task_blk_io_accounting_add(struct proc_io_accounting *dst, - struct proc_io_accounting *src) +static inline void task_blk_io_accounting_add(struct task_io_accounting *dst, + struct task_io_accounting *src) { } #endif /* CONFIG_TASK_IO_ACCOUNTING */ #ifdef CONFIG_TASK_XACCT -static inline void task_chr_io_accounting_add(struct proc_io_accounting *dst, - struct proc_io_accounting *src) +static inline void task_chr_io_accounting_add(struct task_io_accounting *dst, + struct task_io_accounting *src) { - dst->chr.rchar += src->chr.rchar; - dst->chr.wchar += src->chr.wchar; - dst->chr.syscr += src->chr.syscr; - dst->chr.syscw += src->chr.syscw; + dst->rchar += src->rchar; + dst->wchar += src->wchar; + dst->syscr += src->syscr; + dst->syscw += src->syscw; } #else -static inline void task_chr_io_accounting_add(struct proc_io_accounting *dst, - struct proc_io_accounting *src) +static inline void task_chr_io_accounting_add(struct task_io_accounting *dst, + struct task_io_accounting *src) { } #endif /* CONFIG_TASK_XACCT */ -static inline void task_io_accounting_add(struct proc_io_accounting *dst, - struct proc_io_accounting *src) +static inline void task_io_accounting_add(struct task_io_accounting *dst, + struct task_io_accounting *src) { task_chr_io_accounting_add(dst, src); task_blk_io_accounting_add(dst, src); diff --git a/kernel/tsacct.c b/kernel/tsacct.c index f9cd2561689c..8ebcd8532dfb 100644 --- a/kernel/tsacct.c +++ b/kernel/tsacct.c @@ -94,14 +94,14 @@ void xacct_add_tsk(struct taskstats *stats, struct task_struct *p) stats->hiwater_vm = mm->hiwater_vm * PAGE_SIZE / KB; mmput(mm); } - stats->read_char = p->ioac.chr.rchar; - stats->write_char = p->ioac.chr.wchar; - stats->read_syscalls = p->ioac.chr.syscr; - stats->write_syscalls = p->ioac.chr.syscw; + stats->read_char = p->ioac.rchar; + stats->write_char = p->ioac.wchar; + stats->read_syscalls = p->ioac.syscr; + stats->write_syscalls = p->ioac.syscw; #ifdef CONFIG_TASK_IO_ACCOUNTING - stats->read_bytes = p->ioac.blk.read_bytes; - stats->write_bytes = p->ioac.blk.write_bytes; - stats->cancelled_write_bytes = p->ioac.blk.cancelled_write_bytes; + stats->read_bytes = p->ioac.read_bytes; + stats->write_bytes = p->ioac.write_bytes; + stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes; #else stats->read_bytes = 0; stats->write_bytes = 0; -- cgit v1.3-18-gd494 From 15bba37d62351749c3915add81f673b256952ee1 Mon Sep 17 00:00:00 2001 From: WANG Cong Date: Thu, 24 Jul 2008 15:41:48 +0100 Subject: module: fix build warning with !CONFIG_KALLSYMS MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch fixed the warning: CC kernel/module.o /home/wangcong/Projects/linux-2.6/kernel/module.c:332: warning: ‘lookup_symbol’ defined but not used Signed-off-by: WANG Cong Signed-off-by: Rusty Russell --- kernel/module.c | 25 +++++++++++++------------ 1 file changed, 13 insertions(+), 12 deletions(-) (limited to 'kernel') diff --git a/kernel/module.c b/kernel/module.c index d8b5605132a0..d861bd5b8c10 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -325,18 +325,6 @@ static unsigned long find_symbol(const char *name, return -ENOENT; } -/* lookup symbol in given range of kernel_symbols */ -static const struct kernel_symbol *lookup_symbol(const char *name, - const struct kernel_symbol *start, - const struct kernel_symbol *stop) -{ - const struct kernel_symbol *ks = start; - for (; ks < stop; ks++) - if (strcmp(ks->name, name) == 0) - return ks; - return NULL; -} - /* Search for module by name: must hold module_mutex. */ static struct module *find_module(const char *name) { @@ -1703,6 +1691,19 @@ static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs, } #ifdef CONFIG_KALLSYMS + +/* lookup symbol in given range of kernel_symbols */ +static const struct kernel_symbol *lookup_symbol(const char *name, + const struct kernel_symbol *start, + const struct kernel_symbol *stop) +{ + const struct kernel_symbol *ks = start; + for (; ks < stop; ks++) + if (strcmp(ks->name, name) == 0) + return ks; + return NULL; +} + static int is_exported(const char *name, const struct module *mod) { if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab)) -- cgit v1.3-18-gd494 From 5c2aed622571ac7c3c6ec182d6d3c318e4b45c8b Mon Sep 17 00:00:00 2001 From: Jason Baron Date: Thu, 28 Feb 2008 11:33:03 -0500 Subject: stop_machine: add ALL_CPUS option -allow stop_mahcine_run() to call a function on all cpus. Calling stop_machine_run() with a 'ALL_CPUS' invokes this new behavior. stop_machine_run() proceeds as normal until the calling cpu has invoked 'fn'. Then, we tell all the other cpus to call 'fn'. Signed-off-by: Jason Baron Signed-off-by: Mathieu Desnoyers Signed-off-by: Rusty Russell CC: Adrian Bunk CC: Andi Kleen CC: Alexey Dobriyan CC: Christoph Hellwig CC: mingo@elte.hu CC: akpm@osdl.org --- include/linux/stop_machine.h | 8 +++++++- kernel/stop_machine.c | 32 +++++++++++++++++++++++++------- 2 files changed, 32 insertions(+), 8 deletions(-) (limited to 'kernel') diff --git a/include/linux/stop_machine.h b/include/linux/stop_machine.h index 5bfc553bdb21..18af011c13af 100644 --- a/include/linux/stop_machine.h +++ b/include/linux/stop_machine.h @@ -8,11 +8,17 @@ #include #if defined(CONFIG_STOP_MACHINE) && defined(CONFIG_SMP) + +#define ALL_CPUS ~0U + /** * stop_machine_run: freeze the machine on all CPUs and run this function * @fn: the function to run * @data: the data ptr for the @fn() - * @cpu: the cpu to run @fn() on (or any, if @cpu == NR_CPUS. + * @cpu: if @cpu == n, run @fn() on cpu n + * if @cpu == NR_CPUS, run @fn() on any cpu + * if @cpu == ALL_CPUS, run @fn() first on the calling cpu, and then + * concurrently on all the other cpus * * Description: This causes a thread to be scheduled on every other cpu, * each of which disables interrupts, and finally interrupts are disabled diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 738b411ff2d3..a473bd0cb71b 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -22,9 +22,17 @@ enum stopmachine_state { STOPMACHINE_WAIT, STOPMACHINE_PREPARE, STOPMACHINE_DISABLE_IRQ, + STOPMACHINE_RUN, STOPMACHINE_EXIT, }; +struct stop_machine_data { + int (*fn)(void *); + void *data; + struct completion done; + int run_all; +} smdata; + static enum stopmachine_state stopmachine_state; static unsigned int stopmachine_num_threads; static atomic_t stopmachine_thread_ack; @@ -33,6 +41,7 @@ static int stopmachine(void *cpu) { int irqs_disabled = 0; int prepared = 0; + int ran = 0; cpumask_of_cpu_ptr(cpumask, (int)(long)cpu); set_cpus_allowed_ptr(current, cpumask); @@ -58,6 +67,11 @@ static int stopmachine(void *cpu) prepared = 1; smp_mb(); /* Must read state first. */ atomic_inc(&stopmachine_thread_ack); + } else if (stopmachine_state == STOPMACHINE_RUN && !ran) { + smdata.fn(smdata.data); + ran = 1; + smp_mb(); /* Must read state first. */ + atomic_inc(&stopmachine_thread_ack); } /* Yield in first stage: migration threads need to * help our sisters onto their CPUs. */ @@ -136,11 +150,10 @@ static void restart_machine(void) preempt_enable_no_resched(); } -struct stop_machine_data { - int (*fn)(void *); - void *data; - struct completion done; -}; +static void run_other_cpus(void) +{ + stopmachine_set_state(STOPMACHINE_RUN); +} static int do_stop(void *_smdata) { @@ -150,6 +163,8 @@ static int do_stop(void *_smdata) ret = stop_machine(); if (ret == 0) { ret = smdata->fn(smdata->data); + if (smdata->run_all) + run_other_cpus(); restart_machine(); } @@ -173,14 +188,17 @@ struct task_struct *__stop_machine_run(int (*fn)(void *), void *data, struct stop_machine_data smdata; struct task_struct *p; + mutex_lock(&stopmachine_mutex); + smdata.fn = fn; smdata.data = data; + smdata.run_all = (cpu == ALL_CPUS) ? 1 : 0; init_completion(&smdata.done); - mutex_lock(&stopmachine_mutex); + smp_wmb(); /* make sure other cpus see smdata updates */ /* If they don't care which CPU fn runs on, bind to any online one. */ - if (cpu == NR_CPUS) + if (cpu == NR_CPUS || cpu == ALL_CPUS) cpu = raw_smp_processor_id(); p = kthread_create(do_stop, &smdata, "kstopmachine"); -- cgit v1.3-18-gd494 From ffdb5976c47609c862917d4c186ecbb5706d2dda Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Mon, 28 Jul 2008 12:16:28 -0500 Subject: Simplify stop_machine stop_machine creates a kthread which creates kernel threads. We can create those threads directly and simplify things a little. Some care must be taken with CPU hotunplug, which has special needs, but that code seems more robust than it was in the past. Signed-off-by: Rusty Russell Acked-by: Christian Borntraeger --- include/linux/stop_machine.h | 20 ++- kernel/cpu.c | 13 +- kernel/stop_machine.c | 293 ++++++++++++++++++------------------------- 3 files changed, 136 insertions(+), 190 deletions(-) (limited to 'kernel') diff --git a/include/linux/stop_machine.h b/include/linux/stop_machine.h index 18af011c13af..36c2c7284eb3 100644 --- a/include/linux/stop_machine.h +++ b/include/linux/stop_machine.h @@ -17,13 +17,12 @@ * @data: the data ptr for the @fn() * @cpu: if @cpu == n, run @fn() on cpu n * if @cpu == NR_CPUS, run @fn() on any cpu - * if @cpu == ALL_CPUS, run @fn() first on the calling cpu, and then - * concurrently on all the other cpus + * if @cpu == ALL_CPUS, run @fn() on every online CPU. * - * Description: This causes a thread to be scheduled on every other cpu, - * each of which disables interrupts, and finally interrupts are disabled - * on the current CPU. The result is that noone is holding a spinlock - * or inside any other preempt-disabled region when @fn() runs. + * Description: This causes a thread to be scheduled on every cpu, + * each of which disables interrupts. The result is that noone is + * holding a spinlock or inside any other preempt-disabled region when + * @fn() runs. * * This can be thought of as a very heavy write lock, equivalent to * grabbing every spinlock in the kernel. */ @@ -35,13 +34,10 @@ int stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu); * @data: the data ptr for the @fn * @cpu: the cpu to run @fn on (or any, if @cpu == NR_CPUS. * - * Description: This is a special version of the above, which returns the - * thread which has run @fn(): kthread_stop will return the return value - * of @fn(). Used by hotplug cpu. + * Description: This is a special version of the above, which assumes cpus + * won't come or go while it's being called. Used by hotplug cpu. */ -struct task_struct *__stop_machine_run(int (*fn)(void *), void *data, - unsigned int cpu); - +int __stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu); #else static inline int stop_machine_run(int (*fn)(void *), void *data, diff --git a/kernel/cpu.c b/kernel/cpu.c index 10ba5f1004a5..cf79bb911371 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -216,7 +216,6 @@ static int __ref take_cpu_down(void *_param) static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) { int err, nr_calls = 0; - struct task_struct *p; cpumask_t old_allowed, tmp; void *hcpu = (void *)(long)cpu; unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; @@ -250,19 +249,15 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) cpu_clear(cpu, tmp); set_cpus_allowed_ptr(current, &tmp); - p = __stop_machine_run(take_cpu_down, &tcd_param, cpu); + err = __stop_machine_run(take_cpu_down, &tcd_param, cpu); - if (IS_ERR(p) || cpu_online(cpu)) { + if (err || cpu_online(cpu)) { /* CPU didn't die: tell everyone. Can't complain. */ if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod, hcpu) == NOTIFY_BAD) BUG(); - if (IS_ERR(p)) { - err = PTR_ERR(p); - goto out_allowed; - } - goto out_thread; + goto out_allowed; } /* Wait for it to sleep (leaving idle task). */ @@ -279,8 +274,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) check_for_tasks(cpu); -out_thread: - err = kthread_stop(p); out_allowed: set_cpus_allowed_ptr(current, &old_allowed); out_release: diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index a473bd0cb71b..35882dccc943 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -1,4 +1,4 @@ -/* Copyright 2005 Rusty Russell rusty@rustcorp.com.au IBM Corporation. +/* Copyright 2008, 2005 Rusty Russell rusty@rustcorp.com.au IBM Corporation. * GPL v2 and any later version. */ #include @@ -13,220 +13,177 @@ #include #include -/* Since we effect priority and affinity (both of which are visible - * to, and settable by outside processes) we do indirection via a - * kthread. */ - -/* Thread to stop each CPU in user context. */ +/* This controls the threads on each CPU. */ enum stopmachine_state { - STOPMACHINE_WAIT, + /* Dummy starting state for thread. */ + STOPMACHINE_NONE, + /* Awaiting everyone to be scheduled. */ STOPMACHINE_PREPARE, + /* Disable interrupts. */ STOPMACHINE_DISABLE_IRQ, + /* Run the function */ STOPMACHINE_RUN, + /* Exit */ STOPMACHINE_EXIT, }; +static enum stopmachine_state state; struct stop_machine_data { int (*fn)(void *); void *data; - struct completion done; - int run_all; -} smdata; + int fnret; +}; -static enum stopmachine_state stopmachine_state; -static unsigned int stopmachine_num_threads; -static atomic_t stopmachine_thread_ack; +/* Like num_online_cpus(), but hotplug cpu uses us, so we need this. */ +static unsigned int num_threads; +static atomic_t thread_ack; +static struct completion finished; +static DEFINE_MUTEX(lock); -static int stopmachine(void *cpu) +static void set_state(enum stopmachine_state newstate) { - int irqs_disabled = 0; - int prepared = 0; - int ran = 0; - cpumask_of_cpu_ptr(cpumask, (int)(long)cpu); - - set_cpus_allowed_ptr(current, cpumask); - - /* Ack: we are alive */ - smp_mb(); /* Theoretically the ack = 0 might not be on this CPU yet. */ - atomic_inc(&stopmachine_thread_ack); - - /* Simple state machine */ - while (stopmachine_state != STOPMACHINE_EXIT) { - if (stopmachine_state == STOPMACHINE_DISABLE_IRQ - && !irqs_disabled) { - local_irq_disable(); - hard_irq_disable(); - irqs_disabled = 1; - /* Ack: irqs disabled. */ - smp_mb(); /* Must read state first. */ - atomic_inc(&stopmachine_thread_ack); - } else if (stopmachine_state == STOPMACHINE_PREPARE - && !prepared) { - /* Everyone is in place, hold CPU. */ - preempt_disable(); - prepared = 1; - smp_mb(); /* Must read state first. */ - atomic_inc(&stopmachine_thread_ack); - } else if (stopmachine_state == STOPMACHINE_RUN && !ran) { - smdata.fn(smdata.data); - ran = 1; - smp_mb(); /* Must read state first. */ - atomic_inc(&stopmachine_thread_ack); - } - /* Yield in first stage: migration threads need to - * help our sisters onto their CPUs. */ - if (!prepared && !irqs_disabled) - yield(); - cpu_relax(); - } - - /* Ack: we are exiting. */ - smp_mb(); /* Must read state first. */ - atomic_inc(&stopmachine_thread_ack); - - if (irqs_disabled) - local_irq_enable(); - if (prepared) - preempt_enable(); - - return 0; + /* Reset ack counter. */ + atomic_set(&thread_ack, num_threads); + smp_wmb(); + state = newstate; } -/* Change the thread state */ -static void stopmachine_set_state(enum stopmachine_state state) +/* Last one to ack a state moves to the next state. */ +static void ack_state(void) { - atomic_set(&stopmachine_thread_ack, 0); - smp_wmb(); - stopmachine_state = state; - while (atomic_read(&stopmachine_thread_ack) != stopmachine_num_threads) - cpu_relax(); + if (atomic_dec_and_test(&thread_ack)) { + /* If we're the last one to ack the EXIT, we're finished. */ + if (state == STOPMACHINE_EXIT) + complete(&finished); + else + set_state(state + 1); + } } -static int stop_machine(void) +/* This is the actual thread which stops the CPU. It exits by itself rather + * than waiting for kthread_stop(), because it's easier for hotplug CPU. */ +static int stop_cpu(struct stop_machine_data *smdata) { - int i, ret = 0; - - atomic_set(&stopmachine_thread_ack, 0); - stopmachine_num_threads = 0; - stopmachine_state = STOPMACHINE_WAIT; + enum stopmachine_state curstate = STOPMACHINE_NONE; + int uninitialized_var(ret); - for_each_online_cpu(i) { - if (i == raw_smp_processor_id()) - continue; - ret = kernel_thread(stopmachine, (void *)(long)i,CLONE_KERNEL); - if (ret < 0) - break; - stopmachine_num_threads++; - } - - /* Wait for them all to come to life. */ - while (atomic_read(&stopmachine_thread_ack) != stopmachine_num_threads) { - yield(); + /* Simple state machine */ + do { + /* Chill out and ensure we re-read stopmachine_state. */ cpu_relax(); - } - - /* If some failed, kill them all. */ - if (ret < 0) { - stopmachine_set_state(STOPMACHINE_EXIT); - return ret; - } - - /* Now they are all started, make them hold the CPUs, ready. */ - preempt_disable(); - stopmachine_set_state(STOPMACHINE_PREPARE); - - /* Make them disable irqs. */ - local_irq_disable(); - hard_irq_disable(); - stopmachine_set_state(STOPMACHINE_DISABLE_IRQ); - - return 0; -} + if (state != curstate) { + curstate = state; + switch (curstate) { + case STOPMACHINE_DISABLE_IRQ: + local_irq_disable(); + hard_irq_disable(); + break; + case STOPMACHINE_RUN: + /* |= allows error detection if functions on + * multiple CPUs. */ + smdata->fnret |= smdata->fn(smdata->data); + break; + default: + break; + } + ack_state(); + } + } while (curstate != STOPMACHINE_EXIT); -static void restart_machine(void) -{ - stopmachine_set_state(STOPMACHINE_EXIT); local_irq_enable(); - preempt_enable_no_resched(); + do_exit(0); } -static void run_other_cpus(void) +/* Callback for CPUs which aren't supposed to do anything. */ +static int chill(void *unused) { - stopmachine_set_state(STOPMACHINE_RUN); + return 0; } -static int do_stop(void *_smdata) +int __stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu) { - struct stop_machine_data *smdata = _smdata; - int ret; + int i, err; + struct stop_machine_data active, idle; + struct task_struct **threads; + + active.fn = fn; + active.data = data; + active.fnret = 0; + idle.fn = chill; + idle.data = NULL; + + /* If they don't care which cpu fn runs on, just pick one. */ + if (cpu == NR_CPUS) + cpu = any_online_cpu(cpu_online_map); + + /* This could be too big for stack on large machines. */ + threads = kcalloc(NR_CPUS, sizeof(threads[0]), GFP_KERNEL); + if (!threads) + return -ENOMEM; + + /* Set up initial state. */ + mutex_lock(&lock); + init_completion(&finished); + num_threads = num_online_cpus(); + set_state(STOPMACHINE_PREPARE); - ret = stop_machine(); - if (ret == 0) { - ret = smdata->fn(smdata->data); - if (smdata->run_all) - run_other_cpus(); - restart_machine(); - } + for_each_online_cpu(i) { + struct stop_machine_data *smdata; + struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; - /* We're done: you can kthread_stop us now */ - complete(&smdata->done); + if (cpu == ALL_CPUS || i == cpu) + smdata = &active; + else + smdata = &idle; + + threads[i] = kthread_create((void *)stop_cpu, smdata, "kstop%u", + i); + if (IS_ERR(threads[i])) { + err = PTR_ERR(threads[i]); + threads[i] = NULL; + goto kill_threads; + } - /* Wait for kthread_stop */ - set_current_state(TASK_INTERRUPTIBLE); - while (!kthread_should_stop()) { - schedule(); - set_current_state(TASK_INTERRUPTIBLE); - } - __set_current_state(TASK_RUNNING); - return ret; -} + /* Place it onto correct cpu. */ + kthread_bind(threads[i], i); -struct task_struct *__stop_machine_run(int (*fn)(void *), void *data, - unsigned int cpu) -{ - static DEFINE_MUTEX(stopmachine_mutex); - struct stop_machine_data smdata; - struct task_struct *p; + /* Make it highest prio. */ + if (sched_setscheduler_nocheck(threads[i], SCHED_FIFO, ¶m)) + BUG(); + } - mutex_lock(&stopmachine_mutex); + /* We've created all the threads. Wake them all: hold this CPU so one + * doesn't hit this CPU until we're ready. */ + cpu = get_cpu(); + for_each_online_cpu(i) + wake_up_process(threads[i]); - smdata.fn = fn; - smdata.data = data; - smdata.run_all = (cpu == ALL_CPUS) ? 1 : 0; - init_completion(&smdata.done); + /* This will release the thread on our CPU. */ + put_cpu(); + wait_for_completion(&finished); + mutex_unlock(&lock); - smp_wmb(); /* make sure other cpus see smdata updates */ + kfree(threads); - /* If they don't care which CPU fn runs on, bind to any online one. */ - if (cpu == NR_CPUS || cpu == ALL_CPUS) - cpu = raw_smp_processor_id(); + return active.fnret; - p = kthread_create(do_stop, &smdata, "kstopmachine"); - if (!IS_ERR(p)) { - struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; +kill_threads: + for_each_online_cpu(i) + if (threads[i]) + kthread_stop(threads[i]); + mutex_unlock(&lock); - /* One high-prio thread per cpu. We'll do this one. */ - sched_setscheduler_nocheck(p, SCHED_FIFO, ¶m); - kthread_bind(p, cpu); - wake_up_process(p); - wait_for_completion(&smdata.done); - } - mutex_unlock(&stopmachine_mutex); - return p; + kfree(threads); + return err; } int stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu) { - struct task_struct *p; int ret; /* No CPUs can come up or down during this. */ get_online_cpus(); - p = __stop_machine_run(fn, data, cpu); - if (!IS_ERR(p)) - ret = kthread_stop(p); - else - ret = PTR_ERR(p); + ret = __stop_machine_run(fn, data, cpu); put_online_cpus(); return ret; -- cgit v1.3-18-gd494 From 04321587584272f4e8b9818f319f40caf8eeee13 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Mon, 28 Jul 2008 12:16:29 -0500 Subject: Hotplug CPU: don't check cpu_online after take_cpu_down Akinobu points out that if take_cpu_down() succeeds, the cpu must be offline. Remove the cpu_online() check, and put a BUG_ON(). Quoting Akinobu Mita: Actually the cpu_online() check was necessary before appling this stop_machine: simplify patch. With old __stop_machine_run(), __stop_machine_run() could succeed (return !IS_ERR(p) value) even if take_cpu_down() returned non-zero value. The return value of take_cpu_down() was obtained through kthread_stop().. Signed-off-by: Rusty Russell Cc: "Akinobu Mita" --- kernel/cpu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/cpu.c b/kernel/cpu.c index cf79bb911371..53cf508f975a 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -250,8 +250,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) set_cpus_allowed_ptr(current, &tmp); err = __stop_machine_run(take_cpu_down, &tcd_param, cpu); - - if (err || cpu_online(cpu)) { + if (err) { /* CPU didn't die: tell everyone. Can't complain. */ if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod, hcpu) == NOTIFY_BAD) @@ -259,6 +258,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) goto out_allowed; } + BUG_ON(cpu_online(cpu)); /* Wait for it to sleep (leaving idle task). */ while (!idle_cpu(cpu)) -- cgit v1.3-18-gd494 From eeec4fad963490821348a331cca6102ae1c4a7a3 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Mon, 28 Jul 2008 12:16:30 -0500 Subject: stop_machine(): stop_machine_run() changed to use cpu mask Instead of a "cpu" arg with magic values NR_CPUS (any cpu) and ~0 (all cpus), pass a cpumask_t. Allow NULL for the common case (where we don't care which CPU the function is run on): temporary cpumask_t's are usually considered bad for stack space. This deprecates stop_machine_run, to be removed soon when all the callers are dead. Signed-off-by: Rusty Russell --- include/linux/stop_machine.h | 34 ++++++++++++++++++++++++---------- kernel/cpu.c | 3 ++- kernel/stop_machine.c | 27 +++++++++++++-------------- 3 files changed, 39 insertions(+), 25 deletions(-) (limited to 'kernel') diff --git a/include/linux/stop_machine.h b/include/linux/stop_machine.h index 36c2c7284eb3..f1cb0ba6d715 100644 --- a/include/linux/stop_machine.h +++ b/include/linux/stop_machine.h @@ -5,19 +5,19 @@ (and more). So the "read" side to such a lock is anything which diables preeempt. */ #include +#include #include #if defined(CONFIG_STOP_MACHINE) && defined(CONFIG_SMP) +/* Deprecated, but useful for transition. */ #define ALL_CPUS ~0U /** - * stop_machine_run: freeze the machine on all CPUs and run this function + * stop_machine: freeze the machine on all CPUs and run this function * @fn: the function to run * @data: the data ptr for the @fn() - * @cpu: if @cpu == n, run @fn() on cpu n - * if @cpu == NR_CPUS, run @fn() on any cpu - * if @cpu == ALL_CPUS, run @fn() on every online CPU. + * @cpus: the cpus to run the @fn() on (NULL = any online cpu) * * Description: This causes a thread to be scheduled on every cpu, * each of which disables interrupts. The result is that noone is @@ -26,22 +26,22 @@ * * This can be thought of as a very heavy write lock, equivalent to * grabbing every spinlock in the kernel. */ -int stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu); +int stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus); /** - * __stop_machine_run: freeze the machine on all CPUs and run this function + * __stop_machine: freeze the machine on all CPUs and run this function * @fn: the function to run * @data: the data ptr for the @fn - * @cpu: the cpu to run @fn on (or any, if @cpu == NR_CPUS. + * @cpus: the cpus to run the @fn() on (NULL = any online cpu) * * Description: This is a special version of the above, which assumes cpus * won't come or go while it's being called. Used by hotplug cpu. */ -int __stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu); +int __stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus); #else -static inline int stop_machine_run(int (*fn)(void *), void *data, - unsigned int cpu) +static inline int stop_machine(int (*fn)(void *), void *data, + const cpumask_t *cpus) { int ret; local_irq_disable(); @@ -50,4 +50,18 @@ static inline int stop_machine_run(int (*fn)(void *), void *data, return ret; } #endif /* CONFIG_SMP */ + +static inline int __deprecated stop_machine_run(int (*fn)(void *), void *data, + unsigned int cpu) +{ + /* If they don't care which cpu fn runs on, just pick one. */ + if (cpu == NR_CPUS) + return stop_machine(fn, data, NULL); + else if (cpu == ~0U) + return stop_machine(fn, data, &cpu_possible_map); + else { + cpumask_t cpus = cpumask_of_cpu(cpu); + return stop_machine(fn, data, &cpus); + } +} #endif /* _LINUX_STOP_MACHINE */ diff --git a/kernel/cpu.c b/kernel/cpu.c index 53cf508f975a..29510d68338a 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -248,8 +248,9 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) cpus_setall(tmp); cpu_clear(cpu, tmp); set_cpus_allowed_ptr(current, &tmp); + tmp = cpumask_of_cpu(cpu); - err = __stop_machine_run(take_cpu_down, &tcd_param, cpu); + err = __stop_machine(take_cpu_down, &tcd_param, &tmp); if (err) { /* CPU didn't die: tell everyone. Can't complain. */ if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod, diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 35882dccc943..e446c7c7d6a9 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -100,7 +100,7 @@ static int chill(void *unused) return 0; } -int __stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu) +int __stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus) { int i, err; struct stop_machine_data active, idle; @@ -112,10 +112,6 @@ int __stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu) idle.fn = chill; idle.data = NULL; - /* If they don't care which cpu fn runs on, just pick one. */ - if (cpu == NR_CPUS) - cpu = any_online_cpu(cpu_online_map); - /* This could be too big for stack on large machines. */ threads = kcalloc(NR_CPUS, sizeof(threads[0]), GFP_KERNEL); if (!threads) @@ -128,13 +124,16 @@ int __stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu) set_state(STOPMACHINE_PREPARE); for_each_online_cpu(i) { - struct stop_machine_data *smdata; + struct stop_machine_data *smdata = &idle; struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; - if (cpu == ALL_CPUS || i == cpu) - smdata = &active; - else - smdata = &idle; + if (!cpus) { + if (i == first_cpu(cpu_online_map)) + smdata = &active; + } else { + if (cpu_isset(i, *cpus)) + smdata = &active; + } threads[i] = kthread_create((void *)stop_cpu, smdata, "kstop%u", i); @@ -154,7 +153,7 @@ int __stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu) /* We've created all the threads. Wake them all: hold this CPU so one * doesn't hit this CPU until we're ready. */ - cpu = get_cpu(); + get_cpu(); for_each_online_cpu(i) wake_up_process(threads[i]); @@ -177,15 +176,15 @@ kill_threads: return err; } -int stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu) +int stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus) { int ret; /* No CPUs can come up or down during this. */ get_online_cpus(); - ret = __stop_machine_run(fn, data, cpu); + ret = __stop_machine(fn, data, cpus); put_online_cpus(); return ret; } -EXPORT_SYMBOL_GPL(stop_machine_run); +EXPORT_SYMBOL_GPL(stop_machine); -- cgit v1.3-18-gd494 From 9b1a4d38373a5581a4e01032a3ccdd94cd93477b Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Mon, 28 Jul 2008 12:16:30 -0500 Subject: stop_machine: Wean existing callers off stop_machine_run() Signed-off-by: Rusty Russell --- arch/s390/kernel/kprobes.c | 6 +++--- drivers/char/hw_random/intel-rng.c | 6 +++--- kernel/module.c | 8 ++++---- kernel/rcuclassic.c | 4 ++-- mm/page_alloc.c | 4 ++-- 5 files changed, 14 insertions(+), 14 deletions(-) (limited to 'kernel') diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c index 4f82e5b5f879..569079ec4ff0 100644 --- a/arch/s390/kernel/kprobes.c +++ b/arch/s390/kernel/kprobes.c @@ -197,7 +197,7 @@ void __kprobes arch_arm_kprobe(struct kprobe *p) args.new = BREAKPOINT_INSTRUCTION; kcb->kprobe_status = KPROBE_SWAP_INST; - stop_machine_run(swap_instruction, &args, NR_CPUS); + stop_machine(swap_instruction, &args, NULL); kcb->kprobe_status = status; } @@ -212,7 +212,7 @@ void __kprobes arch_disarm_kprobe(struct kprobe *p) args.new = p->opcode; kcb->kprobe_status = KPROBE_SWAP_INST; - stop_machine_run(swap_instruction, &args, NR_CPUS); + stop_machine(swap_instruction, &args, NULL); kcb->kprobe_status = status; } @@ -331,7 +331,7 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) * No kprobe at this address. The fault has not been * caused by a kprobe breakpoint. The race of breakpoint * vs. kprobe remove does not exist because on s390 we - * use stop_machine_run to arm/disarm the breakpoints. + * use stop_machine to arm/disarm the breakpoints. */ goto no_kprobe; diff --git a/drivers/char/hw_random/intel-rng.c b/drivers/char/hw_random/intel-rng.c index 27fdc0866496..8a2fce0756ec 100644 --- a/drivers/char/hw_random/intel-rng.c +++ b/drivers/char/hw_random/intel-rng.c @@ -241,7 +241,7 @@ static int __init intel_rng_hw_init(void *_intel_rng_hw) struct intel_rng_hw *intel_rng_hw = _intel_rng_hw; u8 mfc, dvc; - /* interrupts disabled in stop_machine_run call */ + /* interrupts disabled in stop_machine call */ if (!(intel_rng_hw->fwh_dec_en1_val & FWH_F8_EN_MASK)) pci_write_config_byte(intel_rng_hw->dev, @@ -365,10 +365,10 @@ static int __init mod_init(void) * location with the Read ID command, all activity on the system * must be stopped until the state is back to normal. * - * Use stop_machine_run because IPIs can be blocked by disabling + * Use stop_machine because IPIs can be blocked by disabling * interrupts. */ - err = stop_machine_run(intel_rng_hw_init, intel_rng_hw, NR_CPUS); + err = stop_machine(intel_rng_hw_init, intel_rng_hw, NULL); pci_dev_put(dev); iounmap(intel_rng_hw->mem); kfree(intel_rng_hw); diff --git a/kernel/module.c b/kernel/module.c index d861bd5b8c10..61d212120df4 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -678,7 +678,7 @@ static int try_stop_module(struct module *mod, int flags, int *forced) if (flags & O_NONBLOCK) { struct stopref sref = { mod, flags, forced }; - return stop_machine_run(__try_stop_module, &sref, NR_CPUS); + return stop_machine(__try_stop_module, &sref, NULL); } else { /* We don't need to stop the machine for this. */ mod->state = MODULE_STATE_GOING; @@ -1416,7 +1416,7 @@ static int __unlink_module(void *_mod) static void free_module(struct module *mod) { /* Delete from various lists */ - stop_machine_run(__unlink_module, mod, NR_CPUS); + stop_machine(__unlink_module, mod, NULL); remove_notes_attrs(mod); remove_sect_attrs(mod); mod_kobject_remove(mod); @@ -2197,7 +2197,7 @@ static struct module *load_module(void __user *umod, /* Now sew it into the lists so we can get lockdep and oops * info during argument parsing. Noone should access us, since * strong_try_module_get() will fail. */ - stop_machine_run(__link_module, mod, NR_CPUS); + stop_machine(__link_module, mod, NULL); /* Size of section 0 is 0, so this works well if no params */ err = parse_args(mod->name, mod->args, @@ -2231,7 +2231,7 @@ static struct module *load_module(void __user *umod, return mod; unlink: - stop_machine_run(__unlink_module, mod, NR_CPUS); + stop_machine(__unlink_module, mod, NULL); module_arch_cleanup(mod); cleanup: kobject_del(&mod->mkobj.kobj); diff --git a/kernel/rcuclassic.c b/kernel/rcuclassic.c index 6f8696c502f4..aad93cdc9f68 100644 --- a/kernel/rcuclassic.c +++ b/kernel/rcuclassic.c @@ -91,8 +91,8 @@ static void force_quiescent_state(struct rcu_data *rdp, * rdp->cpu is the current cpu. * * cpu_online_map is updated by the _cpu_down() - * using stop_machine_run(). Since we're in irqs disabled - * section, stop_machine_run() is not exectuting, hence + * using __stop_machine(). Since we're in irqs disabled + * section, __stop_machine() is not exectuting, hence * the cpu_online_map is stable. * * However, a cpu might have been offlined _just_ before diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 6da667274df5..3cf3d05b6bd4 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2372,7 +2372,7 @@ static void build_zonelist_cache(pg_data_t *pgdat) #endif /* CONFIG_NUMA */ -/* return values int ....just for stop_machine_run() */ +/* return values int ....just for stop_machine() */ static int __build_all_zonelists(void *dummy) { int nid; @@ -2397,7 +2397,7 @@ void build_all_zonelists(void) } else { /* we have to stop all cpus to guarantee there is no user of zonelist */ - stop_machine_run(__build_all_zonelists, NULL, NR_CPUS); + stop_machine(__build_all_zonelists, NULL, NULL); /* cpuset refresh routine should be here */ } vm_total_pages = nr_free_pagecache_pages(); -- cgit v1.3-18-gd494 From 784e2d76007f90d69341b95967160c4fb7829299 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Mon, 28 Jul 2008 12:16:31 -0500 Subject: stop_machine: fix up ftrace.c Simple conversion. Signed-off-by: Rusty Russell Cc: Abhishek Sagar Cc: Ingo Molnar Cc: Steven Rostedt --- kernel/trace/ftrace.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 4231a3dc224a..f6e3af31b403 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -587,7 +587,7 @@ static int __ftrace_modify_code(void *data) static void ftrace_run_update_code(int command) { - stop_machine_run(__ftrace_modify_code, &command, NR_CPUS); + stop_machine(__ftrace_modify_code, &command, NULL); } void ftrace_disable_daemon(void) @@ -787,7 +787,7 @@ static int ftrace_update_code(void) !ftrace_enabled || !ftraced_trigger) return 0; - stop_machine_run(__ftrace_update_code, NULL, NR_CPUS); + stop_machine(__ftrace_update_code, NULL, NULL); return 1; } @@ -1564,7 +1564,7 @@ static int __init ftrace_dynamic_init(void) addr = (unsigned long)ftrace_record_ip; - stop_machine_run(ftrace_dyn_arch_init, &addr, NR_CPUS); + stop_machine(ftrace_dyn_arch_init, &addr, NULL); /* ftrace_dyn_arch_init places the return code in addr */ if (addr) { -- cgit v1.3-18-gd494 From e56b3bc7942982ac2589c942fb345e38bc7a341a Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 28 Jul 2008 11:32:33 -0700 Subject: cpu masks: optimize and clean up cpumask_of_cpu() Clean up and optimize cpumask_of_cpu(), by sharing all the zero words. Instead of stupidly generating all possible i=0...NR_CPUS 2^i patterns creating a huge array of constant bitmasks, realize that the zero words can be shared. In other words, on a 64-bit architecture, we only ever need 64 of these arrays - with a different bit set in one single world (with enough zero words around it so that we can create any bitmask by just offsetting in that big array). And then we just put enough zeroes around it that we can point every single cpumask to be one of those things. So when we have 4k CPU's, instead of having 4k arrays (of 4k bits each, with one bit set in each array - 2MB memory total), we have exactly 64 arrays instead, each 8k bits in size (64kB total). And then we just point cpumask(n) to the right position (which we can calculate dynamically). Once we have the right arrays, getting "cpumask(n)" ends up being: static inline const cpumask_t *get_cpu_mask(unsigned int cpu) { const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG]; p -= cpu / BITS_PER_LONG; return (const cpumask_t *)p; } This brings other advantages and simplifications as well: - we are not wasting memory that is just filled with a single bit in various different places - we don't need all those games to re-create the arrays in some dense format, because they're already going to be dense enough. if we compile a kernel for up to 4k CPU's, "wasting" that 64kB of memory is a non-issue (especially since by doing this "overlapping" trick we probably get better cache behaviour anyway). [ mingo@elte.hu: Converted Linus's mails into a commit. See: http://lkml.org/lkml/2008/7/27/156 http://lkml.org/lkml/2008/7/28/320 Also applied a family filter - which also has the side-effect of leaving out the bits where Linus calls me an idio... Oh, never mind ;-) ] Signed-off-by: Ingo Molnar Cc: Rusty Russell Cc: Andrew Morton Cc: Al Viro Cc: Mike Travis Signed-off-by: Ingo Molnar --- arch/x86/kernel/setup_percpu.c | 23 -------- include/linux/cpumask.h | 26 ++++++++- kernel/cpu.c | 128 +++++++---------------------------------- 3 files changed, 43 insertions(+), 134 deletions(-) (limited to 'kernel') diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index 1cd53dfcd309..76e305e064f9 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -80,26 +80,6 @@ static void __init setup_per_cpu_maps(void) #endif } -#ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP -/* - * Replace static cpumask_of_cpu_map in the initdata section, - * with one that's allocated sized by the possible number of cpus. - * - * (requires nr_cpu_ids to be initialized) - */ -static void __init setup_cpumask_of_cpu(void) -{ - int i; - - /* alloc_bootmem zeroes memory */ - cpumask_of_cpu_map = alloc_bootmem_low(sizeof(cpumask_t) * nr_cpu_ids); - for (i = 0; i < nr_cpu_ids; i++) - cpu_set(i, cpumask_of_cpu_map[i]); -} -#else -static inline void setup_cpumask_of_cpu(void) { } -#endif - #ifdef CONFIG_X86_32 /* * Great future not-so-futuristic plan: make i386 and x86_64 do it @@ -199,9 +179,6 @@ void __init setup_per_cpu_areas(void) /* Setup node to cpumask map */ setup_node_to_cpumask_map(); - - /* Setup cpumask_of_cpu map */ - setup_cpumask_of_cpu(); } #endif diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index 8fa3b6d4a320..96d0509fb8d8 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -265,10 +265,30 @@ static inline void __cpus_shift_left(cpumask_t *dstp, bitmap_shift_left(dstp->bits, srcp->bits, n, nbits); } +/* + * Special-case data structure for "single bit set only" constant CPU masks. + * + * We pre-generate all the 64 (or 32) possible bit positions, with enough + * padding to the left and the right, and return the constant pointer + * appropriately offset. + */ +extern const unsigned long + cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)]; + +static inline const cpumask_t *get_cpu_mask(unsigned int cpu) +{ + const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG]; + p -= cpu / BITS_PER_LONG; + return (const cpumask_t *)p; +} + +/* + * In cases where we take the address of the cpumask immediately, + * gcc optimizes it out (it's a constant) and there's no huge stack + * variable created: + */ +#define cpumask_of_cpu(cpu) ({ *get_cpu_mask(cpu); }) -/* cpumask_of_cpu_map[] is in kernel/cpu.c */ -extern const cpumask_t *cpumask_of_cpu_map; -#define cpumask_of_cpu(cpu) (cpumask_of_cpu_map[cpu]) #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS) diff --git a/kernel/cpu.c b/kernel/cpu.c index a35d8995dc8c..06a8358bb418 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -462,115 +462,27 @@ out: #endif /* CONFIG_SMP */ -/* 64 bits of zeros, for initializers. */ -#if BITS_PER_LONG == 32 -#define Z64 0, 0 -#else -#define Z64 0 -#endif +/* + * cpu_bit_bitmap[] is a special, "compressed" data structure that + * represents all NR_CPUS bits binary values of 1< 4 - CMI0(4), CMI0(5), CMI0(6), CMI0(7), -#endif -#if NR_CPUS > 8 - CMI0(8), CMI0(9), CMI0(10), CMI0(11), - CMI0(12), CMI0(13), CMI0(14), CMI0(15), -#endif -#if NR_CPUS > 16 - CMI0(16), CMI0(17), CMI0(18), CMI0(19), - CMI0(20), CMI0(21), CMI0(22), CMI0(23), - CMI0(24), CMI0(25), CMI0(26), CMI0(27), - CMI0(28), CMI0(29), CMI0(30), CMI0(31), -#endif -#if NR_CPUS > 32 -#if BITS_PER_LONG == 32 - CMI(32, 0), CMI(33, 0), CMI(34, 0), CMI(35, 0), - CMI(36, 0), CMI(37, 0), CMI(38, 0), CMI(39, 0), - CMI(40, 0), CMI(41, 0), CMI(42, 0), CMI(43, 0), - CMI(44, 0), CMI(45, 0), CMI(46, 0), CMI(47, 0), - CMI(48, 0), CMI(49, 0), CMI(50, 0), CMI(51, 0), - CMI(52, 0), CMI(53, 0), CMI(54, 0), CMI(55, 0), - CMI(56, 0), CMI(57, 0), CMI(58, 0), CMI(59, 0), - CMI(60, 0), CMI(61, 0), CMI(62, 0), CMI(63, 0), -#else - CMI0(32), CMI0(33), CMI0(34), CMI0(35), - CMI0(36), CMI0(37), CMI0(38), CMI0(39), - CMI0(40), CMI0(41), CMI0(42), CMI0(43), - CMI0(44), CMI0(45), CMI0(46), CMI0(47), - CMI0(48), CMI0(49), CMI0(50), CMI0(51), - CMI0(52), CMI0(53), CMI0(54), CMI0(55), - CMI0(56), CMI0(57), CMI0(58), CMI0(59), - CMI0(60), CMI0(61), CMI0(62), CMI0(63), -#endif /* BITS_PER_LONG == 64 */ -#endif -#if NR_CPUS > 64 - CMI64(64, Z64), -#endif -#if NR_CPUS > 128 - CMI64(128, Z64, Z64), CMI64(192, Z64, Z64, Z64), -#endif -#if NR_CPUS > 256 - CMI256(256, Z256), -#endif -#if NR_CPUS > 512 - CMI256(512, Z256, Z256), CMI256(768, Z256, Z256, Z256), -#endif -#if NR_CPUS > 1024 - CMI1024(1024, Z1024), -#endif -#if NR_CPUS > 2048 - CMI1024(2048, Z1024, Z1024), CMI1024(3072, Z1024, Z1024, Z1024), -#endif -#if NR_CPUS > 4096 -#error NR_CPUS too big. Fix initializers or set CONFIG_HAVE_CPUMASK_OF_CPU_MAP +const unsigned long cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)] = { + + MASK_DECLARE_8(0), MASK_DECLARE_8(8), + MASK_DECLARE_8(16), MASK_DECLARE_8(24), +#if BITS_PER_LONG > 32 + MASK_DECLARE_8(32), MASK_DECLARE_8(40), + MASK_DECLARE_8(48), MASK_DECLARE_8(56), #endif }; - -const cpumask_t *cpumask_of_cpu_map = cpumask_map; - -EXPORT_SYMBOL_GPL(cpumask_of_cpu_map); +EXPORT_SYMBOL_GPL(cpu_bit_bitmap); -- cgit v1.3-18-gd494 From cddb8a5c14aa89810b40495d94d3d2a0faee6619 Mon Sep 17 00:00:00 2001 From: Andrea Arcangeli Date: Mon, 28 Jul 2008 15:46:29 -0700 Subject: mmu-notifiers: core With KVM/GFP/XPMEM there isn't just the primary CPU MMU pointing to pages. There are secondary MMUs (with secondary sptes and secondary tlbs) too. sptes in the kvm case are shadow pagetables, but when I say spte in mmu-notifier context, I mean "secondary pte". In GRU case there's no actual secondary pte and there's only a secondary tlb because the GRU secondary MMU has no knowledge about sptes and every secondary tlb miss event in the MMU always generates a page fault that has to be resolved by the CPU (this is not the case of KVM where the a secondary tlb miss will walk sptes in hardware and it will refill the secondary tlb transparently to software if the corresponding spte is present). The same way zap_page_range has to invalidate the pte before freeing the page, the spte (and secondary tlb) must also be invalidated before any page is freed and reused. Currently we take a page_count pin on every page mapped by sptes, but that means the pages can't be swapped whenever they're mapped by any spte because they're part of the guest working set. Furthermore a spte unmap event can immediately lead to a page to be freed when the pin is released (so requiring the same complex and relatively slow tlb_gather smp safe logic we have in zap_page_range and that can be avoided completely if the spte unmap event doesn't require an unpin of the page previously mapped in the secondary MMU). The mmu notifiers allow kvm/GRU/XPMEM to attach to the tsk->mm and know when the VM is swapping or freeing or doing anything on the primary MMU so that the secondary MMU code can drop sptes before the pages are freed, avoiding all page pinning and allowing 100% reliable swapping of guest physical address space. Furthermore it avoids the code that teardown the mappings of the secondary MMU, to implement a logic like tlb_gather in zap_page_range that would require many IPI to flush other cpu tlbs, for each fixed number of spte unmapped. To make an example: if what happens on the primary MMU is a protection downgrade (from writeable to wrprotect) the secondary MMU mappings will be invalidated, and the next secondary-mmu-page-fault will call get_user_pages and trigger a do_wp_page through get_user_pages if it called get_user_pages with write=1, and it'll re-establishing an updated spte or secondary-tlb-mapping on the copied page. Or it will setup a readonly spte or readonly tlb mapping if it's a guest-read, if it calls get_user_pages with write=0. This is just an example. This allows to map any page pointed by any pte (and in turn visible in the primary CPU MMU), into a secondary MMU (be it a pure tlb like GRU, or an full MMU with both sptes and secondary-tlb like the shadow-pagetable layer with kvm), or a remote DMA in software like XPMEM (hence needing of schedule in XPMEM code to send the invalidate to the remote node, while no need to schedule in kvm/gru as it's an immediate event like invalidating primary-mmu pte). At least for KVM without this patch it's impossible to swap guests reliably. And having this feature and removing the page pin allows several other optimizations that simplify life considerably. Dependencies: 1) mm_take_all_locks() to register the mmu notifier when the whole VM isn't doing anything with "mm". This allows mmu notifier users to keep track if the VM is in the middle of the invalidate_range_begin/end critical section with an atomic counter incraese in range_begin and decreased in range_end. No secondary MMU page fault is allowed to map any spte or secondary tlb reference, while the VM is in the middle of range_begin/end as any page returned by get_user_pages in that critical section could later immediately be freed without any further ->invalidate_page notification (invalidate_range_begin/end works on ranges and ->invalidate_page isn't called immediately before freeing the page). To stop all page freeing and pagetable overwrites the mmap_sem must be taken in write mode and all other anon_vma/i_mmap locks must be taken too. 2) It'd be a waste to add branches in the VM if nobody could possibly run KVM/GRU/XPMEM on the kernel, so mmu notifiers will only enabled if CONFIG_KVM=m/y. In the current kernel kvm won't yet take advantage of mmu notifiers, but this already allows to compile a KVM external module against a kernel with mmu notifiers enabled and from the next pull from kvm.git we'll start using them. And GRU/XPMEM will also be able to continue the development by enabling KVM=m in their config, until they submit all GRU/XPMEM GPLv2 code to the mainline kernel. Then they can also enable MMU_NOTIFIERS in the same way KVM does it (even if KVM=n). This guarantees nobody selects MMU_NOTIFIER=y if KVM and GRU and XPMEM are all =n. The mmu_notifier_register call can fail because mm_take_all_locks may be interrupted by a signal and return -EINTR. Because mmu_notifier_reigster is used when a driver startup, a failure can be gracefully handled. Here an example of the change applied to kvm to register the mmu notifiers. Usually when a driver startups other allocations are required anyway and -ENOMEM failure paths exists already. struct kvm *kvm_arch_create_vm(void) { struct kvm *kvm = kzalloc(sizeof(struct kvm), GFP_KERNEL); + int err; if (!kvm) return ERR_PTR(-ENOMEM); INIT_LIST_HEAD(&kvm->arch.active_mmu_pages); + kvm->arch.mmu_notifier.ops = &kvm_mmu_notifier_ops; + err = mmu_notifier_register(&kvm->arch.mmu_notifier, current->mm); + if (err) { + kfree(kvm); + return ERR_PTR(err); + } + return kvm; } mmu_notifier_unregister returns void and it's reliable. The patch also adds a few needed but missing includes that would prevent kernel to compile after these changes on non-x86 archs (x86 didn't need them by luck). [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix mm/filemap_xip.c build] [akpm@linux-foundation.org: fix mm/mmu_notifier.c build] Signed-off-by: Andrea Arcangeli Signed-off-by: Nick Piggin Signed-off-by: Christoph Lameter Cc: Jack Steiner Cc: Robin Holt Cc: Nick Piggin Cc: Peter Zijlstra Cc: Kanoj Sarcar Cc: Roland Dreier Cc: Steve Wise Cc: Avi Kivity Cc: Hugh Dickins Cc: Rusty Russell Cc: Anthony Liguori Cc: Chris Wright Cc: Marcelo Tosatti Cc: Eric Dumazet Cc: "Paul E. McKenney" Cc: Izik Eidus Cc: Anthony Liguori Cc: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/kvm/Kconfig | 1 + include/linux/mm_types.h | 4 + include/linux/mmu_notifier.h | 279 +++++++++++++++++++++++++++++++++++++++++++ kernel/fork.c | 3 + mm/Kconfig | 3 + mm/Makefile | 1 + mm/filemap_xip.c | 3 +- mm/fremap.c | 3 + mm/hugetlb.c | 3 + mm/memory.c | 35 +++++- mm/mmap.c | 2 + mm/mmu_notifier.c | 277 ++++++++++++++++++++++++++++++++++++++++++ mm/mprotect.c | 3 + mm/mremap.c | 6 + mm/rmap.c | 13 +- 15 files changed, 623 insertions(+), 13 deletions(-) create mode 100644 include/linux/mmu_notifier.h create mode 100644 mm/mmu_notifier.c (limited to 'kernel') diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index 8d45fabc5f3b..ce3251ce5504 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -21,6 +21,7 @@ config KVM tristate "Kernel-based Virtual Machine (KVM) support" depends on HAVE_KVM select PREEMPT_NOTIFIERS + select MMU_NOTIFIER select ANON_INODES ---help--- Support hosting fully virtualized guest machines using hardware diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 746f975b58ef..386edbe2cb4e 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -10,6 +10,7 @@ #include #include #include +#include #include #include @@ -253,6 +254,9 @@ struct mm_struct { struct file *exe_file; unsigned long num_exe_file_vmas; #endif +#ifdef CONFIG_MMU_NOTIFIER + struct mmu_notifier_mm *mmu_notifier_mm; +#endif }; #endif /* _LINUX_MM_TYPES_H */ diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h new file mode 100644 index 000000000000..b77486d152cd --- /dev/null +++ b/include/linux/mmu_notifier.h @@ -0,0 +1,279 @@ +#ifndef _LINUX_MMU_NOTIFIER_H +#define _LINUX_MMU_NOTIFIER_H + +#include +#include +#include + +struct mmu_notifier; +struct mmu_notifier_ops; + +#ifdef CONFIG_MMU_NOTIFIER + +/* + * The mmu notifier_mm structure is allocated and installed in + * mm->mmu_notifier_mm inside the mm_take_all_locks() protected + * critical section and it's released only when mm_count reaches zero + * in mmdrop(). + */ +struct mmu_notifier_mm { + /* all mmu notifiers registerd in this mm are queued in this list */ + struct hlist_head list; + /* to serialize the list modifications and hlist_unhashed */ + spinlock_t lock; +}; + +struct mmu_notifier_ops { + /* + * Called either by mmu_notifier_unregister or when the mm is + * being destroyed by exit_mmap, always before all pages are + * freed. This can run concurrently with other mmu notifier + * methods (the ones invoked outside the mm context) and it + * should tear down all secondary mmu mappings and freeze the + * secondary mmu. If this method isn't implemented you've to + * be sure that nothing could possibly write to the pages + * through the secondary mmu by the time the last thread with + * tsk->mm == mm exits. + * + * As side note: the pages freed after ->release returns could + * be immediately reallocated by the gart at an alias physical + * address with a different cache model, so if ->release isn't + * implemented because all _software_ driven memory accesses + * through the secondary mmu are terminated by the time the + * last thread of this mm quits, you've also to be sure that + * speculative _hardware_ operations can't allocate dirty + * cachelines in the cpu that could not be snooped and made + * coherent with the other read and write operations happening + * through the gart alias address, so leading to memory + * corruption. + */ + void (*release)(struct mmu_notifier *mn, + struct mm_struct *mm); + + /* + * clear_flush_young is called after the VM is + * test-and-clearing the young/accessed bitflag in the + * pte. This way the VM will provide proper aging to the + * accesses to the page through the secondary MMUs and not + * only to the ones through the Linux pte. + */ + int (*clear_flush_young)(struct mmu_notifier *mn, + struct mm_struct *mm, + unsigned long address); + + /* + * Before this is invoked any secondary MMU is still ok to + * read/write to the page previously pointed to by the Linux + * pte because the page hasn't been freed yet and it won't be + * freed until this returns. If required set_page_dirty has to + * be called internally to this method. + */ + void (*invalidate_page)(struct mmu_notifier *mn, + struct mm_struct *mm, + unsigned long address); + + /* + * invalidate_range_start() and invalidate_range_end() must be + * paired and are called only when the mmap_sem and/or the + * locks protecting the reverse maps are held. The subsystem + * must guarantee that no additional references are taken to + * the pages in the range established between the call to + * invalidate_range_start() and the matching call to + * invalidate_range_end(). + * + * Invalidation of multiple concurrent ranges may be + * optionally permitted by the driver. Either way the + * establishment of sptes is forbidden in the range passed to + * invalidate_range_begin/end for the whole duration of the + * invalidate_range_begin/end critical section. + * + * invalidate_range_start() is called when all pages in the + * range are still mapped and have at least a refcount of one. + * + * invalidate_range_end() is called when all pages in the + * range have been unmapped and the pages have been freed by + * the VM. + * + * The VM will remove the page table entries and potentially + * the page between invalidate_range_start() and + * invalidate_range_end(). If the page must not be freed + * because of pending I/O or other circumstances then the + * invalidate_range_start() callback (or the initial mapping + * by the driver) must make sure that the refcount is kept + * elevated. + * + * If the driver increases the refcount when the pages are + * initially mapped into an address space then either + * invalidate_range_start() or invalidate_range_end() may + * decrease the refcount. If the refcount is decreased on + * invalidate_range_start() then the VM can free pages as page + * table entries are removed. If the refcount is only + * droppped on invalidate_range_end() then the driver itself + * will drop the last refcount but it must take care to flush + * any secondary tlb before doing the final free on the + * page. Pages will no longer be referenced by the linux + * address space but may still be referenced by sptes until + * the last refcount is dropped. + */ + void (*invalidate_range_start)(struct mmu_notifier *mn, + struct mm_struct *mm, + unsigned long start, unsigned long end); + void (*invalidate_range_end)(struct mmu_notifier *mn, + struct mm_struct *mm, + unsigned long start, unsigned long end); +}; + +/* + * The notifier chains are protected by mmap_sem and/or the reverse map + * semaphores. Notifier chains are only changed when all reverse maps and + * the mmap_sem locks are taken. + * + * Therefore notifier chains can only be traversed when either + * + * 1. mmap_sem is held. + * 2. One of the reverse map locks is held (i_mmap_lock or anon_vma->lock). + * 3. No other concurrent thread can access the list (release) + */ +struct mmu_notifier { + struct hlist_node hlist; + const struct mmu_notifier_ops *ops; +}; + +static inline int mm_has_notifiers(struct mm_struct *mm) +{ + return unlikely(mm->mmu_notifier_mm); +} + +extern int mmu_notifier_register(struct mmu_notifier *mn, + struct mm_struct *mm); +extern int __mmu_notifier_register(struct mmu_notifier *mn, + struct mm_struct *mm); +extern void mmu_notifier_unregister(struct mmu_notifier *mn, + struct mm_struct *mm); +extern void __mmu_notifier_mm_destroy(struct mm_struct *mm); +extern void __mmu_notifier_release(struct mm_struct *mm); +extern int __mmu_notifier_clear_flush_young(struct mm_struct *mm, + unsigned long address); +extern void __mmu_notifier_invalidate_page(struct mm_struct *mm, + unsigned long address); +extern void __mmu_notifier_invalidate_range_start(struct mm_struct *mm, + unsigned long start, unsigned long end); +extern void __mmu_notifier_invalidate_range_end(struct mm_struct *mm, + unsigned long start, unsigned long end); + +static inline void mmu_notifier_release(struct mm_struct *mm) +{ + if (mm_has_notifiers(mm)) + __mmu_notifier_release(mm); +} + +static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm, + unsigned long address) +{ + if (mm_has_notifiers(mm)) + return __mmu_notifier_clear_flush_young(mm, address); + return 0; +} + +static inline void mmu_notifier_invalidate_page(struct mm_struct *mm, + unsigned long address) +{ + if (mm_has_notifiers(mm)) + __mmu_notifier_invalidate_page(mm, address); +} + +static inline void mmu_notifier_invalidate_range_start(struct mm_struct *mm, + unsigned long start, unsigned long end) +{ + if (mm_has_notifiers(mm)) + __mmu_notifier_invalidate_range_start(mm, start, end); +} + +static inline void mmu_notifier_invalidate_range_end(struct mm_struct *mm, + unsigned long start, unsigned long end) +{ + if (mm_has_notifiers(mm)) + __mmu_notifier_invalidate_range_end(mm, start, end); +} + +static inline void mmu_notifier_mm_init(struct mm_struct *mm) +{ + mm->mmu_notifier_mm = NULL; +} + +static inline void mmu_notifier_mm_destroy(struct mm_struct *mm) +{ + if (mm_has_notifiers(mm)) + __mmu_notifier_mm_destroy(mm); +} + +/* + * These two macros will sometime replace ptep_clear_flush. + * ptep_clear_flush is impleemnted as macro itself, so this also is + * implemented as a macro until ptep_clear_flush will converted to an + * inline function, to diminish the risk of compilation failure. The + * invalidate_page method over time can be moved outside the PT lock + * and these two macros can be later removed. + */ +#define ptep_clear_flush_notify(__vma, __address, __ptep) \ +({ \ + pte_t __pte; \ + struct vm_area_struct *___vma = __vma; \ + unsigned long ___address = __address; \ + __pte = ptep_clear_flush(___vma, ___address, __ptep); \ + mmu_notifier_invalidate_page(___vma->vm_mm, ___address); \ + __pte; \ +}) + +#define ptep_clear_flush_young_notify(__vma, __address, __ptep) \ +({ \ + int __young; \ + struct vm_area_struct *___vma = __vma; \ + unsigned long ___address = __address; \ + __young = ptep_clear_flush_young(___vma, ___address, __ptep); \ + __young |= mmu_notifier_clear_flush_young(___vma->vm_mm, \ + ___address); \ + __young; \ +}) + +#else /* CONFIG_MMU_NOTIFIER */ + +static inline void mmu_notifier_release(struct mm_struct *mm) +{ +} + +static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm, + unsigned long address) +{ + return 0; +} + +static inline void mmu_notifier_invalidate_page(struct mm_struct *mm, + unsigned long address) +{ +} + +static inline void mmu_notifier_invalidate_range_start(struct mm_struct *mm, + unsigned long start, unsigned long end) +{ +} + +static inline void mmu_notifier_invalidate_range_end(struct mm_struct *mm, + unsigned long start, unsigned long end) +{ +} + +static inline void mmu_notifier_mm_init(struct mm_struct *mm) +{ +} + +static inline void mmu_notifier_mm_destroy(struct mm_struct *mm) +{ +} + +#define ptep_clear_flush_young_notify ptep_clear_flush_young +#define ptep_clear_flush_notify ptep_clear_flush + +#endif /* CONFIG_MMU_NOTIFIER */ + +#endif /* _LINUX_MMU_NOTIFIER_H */ diff --git a/kernel/fork.c b/kernel/fork.c index 8214ba7c8bb1..7ce2ebe84796 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include @@ -414,6 +415,7 @@ static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p) if (likely(!mm_alloc_pgd(mm))) { mm->def_flags = 0; + mmu_notifier_mm_init(mm); return mm; } @@ -446,6 +448,7 @@ void __mmdrop(struct mm_struct *mm) BUG_ON(mm == &init_mm); mm_free_pgd(mm); destroy_context(mm); + mmu_notifier_mm_destroy(mm); free_mm(mm); } EXPORT_SYMBOL_GPL(__mmdrop); diff --git a/mm/Kconfig b/mm/Kconfig index efee5d379df4..446c6588c753 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -208,3 +208,6 @@ config NR_QUICK config VIRT_TO_BUS def_bool y depends on !ARCH_NO_VIRT_TO_BUS + +config MMU_NOTIFIER + bool diff --git a/mm/Makefile b/mm/Makefile index 06ca2381fef1..da4ccf015aea 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -25,6 +25,7 @@ obj-$(CONFIG_SHMEM) += shmem.o obj-$(CONFIG_TMPFS_POSIX_ACL) += shmem_acl.o obj-$(CONFIG_TINY_SHMEM) += tiny-shmem.o obj-$(CONFIG_SLOB) += slob.o +obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o obj-$(CONFIG_SLAB) += slab.o obj-$(CONFIG_SLUB) += slub.o obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c index 98a3f31ccd6a..380ab402d711 100644 --- a/mm/filemap_xip.c +++ b/mm/filemap_xip.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -188,7 +189,7 @@ __xip_unmap (struct address_space * mapping, if (pte) { /* Nuke the page table entry. */ flush_cache_page(vma, address, pte_pfn(*pte)); - pteval = ptep_clear_flush(vma, address, pte); + pteval = ptep_clear_flush_notify(vma, address, pte); page_remove_rmap(page, vma); dec_mm_counter(mm, file_rss); BUG_ON(pte_dirty(pteval)); diff --git a/mm/fremap.c b/mm/fremap.c index 07a9c82ce1a3..7881638e4a12 100644 --- a/mm/fremap.c +++ b/mm/fremap.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include @@ -214,7 +215,9 @@ asmlinkage long sys_remap_file_pages(unsigned long start, unsigned long size, spin_unlock(&mapping->i_mmap_lock); } + mmu_notifier_invalidate_range_start(mm, start, start + size); err = populate_range(mm, vma, start, size, pgoff); + mmu_notifier_invalidate_range_end(mm, start, start + size); if (!err && !(flags & MAP_NONBLOCK)) { if (unlikely(has_write_lock)) { downgrade_write(&mm->mmap_sem); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 3be79dc18c5c..80eb0d31d0d3 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include #include @@ -1672,6 +1673,7 @@ void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, BUG_ON(start & ~huge_page_mask(h)); BUG_ON(end & ~huge_page_mask(h)); + mmu_notifier_invalidate_range_start(mm, start, end); spin_lock(&mm->page_table_lock); for (address = start; address < end; address += sz) { ptep = huge_pte_offset(mm, address); @@ -1713,6 +1715,7 @@ void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, } spin_unlock(&mm->page_table_lock); flush_tlb_range(vma, start, end); + mmu_notifier_invalidate_range_end(mm, start, end); list_for_each_entry_safe(page, tmp, &page_list, lru) { list_del(&page->lru); put_page(page); diff --git a/mm/memory.c b/mm/memory.c index a8ca04faaea6..67f0ab9077d9 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -51,6 +51,7 @@ #include #include #include +#include #include #include @@ -652,6 +653,7 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, unsigned long next; unsigned long addr = vma->vm_start; unsigned long end = vma->vm_end; + int ret; /* * Don't copy ptes where a page fault will fill them correctly. @@ -667,17 +669,33 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, if (is_vm_hugetlb_page(vma)) return copy_hugetlb_page_range(dst_mm, src_mm, vma); + /* + * We need to invalidate the secondary MMU mappings only when + * there could be a permission downgrade on the ptes of the + * parent mm. And a permission downgrade will only happen if + * is_cow_mapping() returns true. + */ + if (is_cow_mapping(vma->vm_flags)) + mmu_notifier_invalidate_range_start(src_mm, addr, end); + + ret = 0; dst_pgd = pgd_offset(dst_mm, addr); src_pgd = pgd_offset(src_mm, addr); do { next = pgd_addr_end(addr, end); if (pgd_none_or_clear_bad(src_pgd)) continue; - if (copy_pud_range(dst_mm, src_mm, dst_pgd, src_pgd, - vma, addr, next)) - return -ENOMEM; + if (unlikely(copy_pud_range(dst_mm, src_mm, dst_pgd, src_pgd, + vma, addr, next))) { + ret = -ENOMEM; + break; + } } while (dst_pgd++, src_pgd++, addr = next, addr != end); - return 0; + + if (is_cow_mapping(vma->vm_flags)) + mmu_notifier_invalidate_range_end(src_mm, + vma->vm_start, end); + return ret; } static unsigned long zap_pte_range(struct mmu_gather *tlb, @@ -881,7 +899,9 @@ unsigned long unmap_vmas(struct mmu_gather **tlbp, unsigned long start = start_addr; spinlock_t *i_mmap_lock = details? details->i_mmap_lock: NULL; int fullmm = (*tlbp)->fullmm; + struct mm_struct *mm = vma->vm_mm; + mmu_notifier_invalidate_range_start(mm, start_addr, end_addr); for ( ; vma && vma->vm_start < end_addr; vma = vma->vm_next) { unsigned long end; @@ -946,6 +966,7 @@ unsigned long unmap_vmas(struct mmu_gather **tlbp, } } out: + mmu_notifier_invalidate_range_end(mm, start_addr, end_addr); return start; /* which is now the end (or restart) address */ } @@ -1616,10 +1637,11 @@ int apply_to_page_range(struct mm_struct *mm, unsigned long addr, { pgd_t *pgd; unsigned long next; - unsigned long end = addr + size; + unsigned long start = addr, end = addr + size; int err; BUG_ON(addr >= end); + mmu_notifier_invalidate_range_start(mm, start, end); pgd = pgd_offset(mm, addr); do { next = pgd_addr_end(addr, end); @@ -1627,6 +1649,7 @@ int apply_to_page_range(struct mm_struct *mm, unsigned long addr, if (err) break; } while (pgd++, addr = next, addr != end); + mmu_notifier_invalidate_range_end(mm, start, end); return err; } EXPORT_SYMBOL_GPL(apply_to_page_range); @@ -1839,7 +1862,7 @@ gotten: * seen in the presence of one thread doing SMC and another * thread doing COW. */ - ptep_clear_flush(vma, address, page_table); + ptep_clear_flush_notify(vma, address, page_table); set_pte_at(mm, address, page_table, entry); update_mmu_cache(vma, address, entry); lru_cache_add_active(new_page); diff --git a/mm/mmap.c b/mm/mmap.c index e5f9cb83d6d4..245c3d69067b 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -2061,6 +2062,7 @@ void exit_mmap(struct mm_struct *mm) /* mm's last user has gone, and its about to be pulled down */ arch_exit_mmap(mm); + mmu_notifier_release(mm); lru_add_drain(); flush_cache_mm(mm); diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c new file mode 100644 index 000000000000..5f4ef0250bee --- /dev/null +++ b/mm/mmu_notifier.c @@ -0,0 +1,277 @@ +/* + * linux/mm/mmu_notifier.c + * + * Copyright (C) 2008 Qumranet, Inc. + * Copyright (C) 2008 SGI + * Christoph Lameter + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + */ + +#include +#include +#include +#include +#include +#include +#include + +/* + * This function can't run concurrently against mmu_notifier_register + * because mm->mm_users > 0 during mmu_notifier_register and exit_mmap + * runs with mm_users == 0. Other tasks may still invoke mmu notifiers + * in parallel despite there being no task using this mm any more, + * through the vmas outside of the exit_mmap context, such as with + * vmtruncate. This serializes against mmu_notifier_unregister with + * the mmu_notifier_mm->lock in addition to RCU and it serializes + * against the other mmu notifiers with RCU. struct mmu_notifier_mm + * can't go away from under us as exit_mmap holds an mm_count pin + * itself. + */ +void __mmu_notifier_release(struct mm_struct *mm) +{ + struct mmu_notifier *mn; + + spin_lock(&mm->mmu_notifier_mm->lock); + while (unlikely(!hlist_empty(&mm->mmu_notifier_mm->list))) { + mn = hlist_entry(mm->mmu_notifier_mm->list.first, + struct mmu_notifier, + hlist); + /* + * We arrived before mmu_notifier_unregister so + * mmu_notifier_unregister will do nothing other than + * to wait ->release to finish and + * mmu_notifier_unregister to return. + */ + hlist_del_init_rcu(&mn->hlist); + /* + * RCU here will block mmu_notifier_unregister until + * ->release returns. + */ + rcu_read_lock(); + spin_unlock(&mm->mmu_notifier_mm->lock); + /* + * if ->release runs before mmu_notifier_unregister it + * must be handled as it's the only way for the driver + * to flush all existing sptes and stop the driver + * from establishing any more sptes before all the + * pages in the mm are freed. + */ + if (mn->ops->release) + mn->ops->release(mn, mm); + rcu_read_unlock(); + spin_lock(&mm->mmu_notifier_mm->lock); + } + spin_unlock(&mm->mmu_notifier_mm->lock); + + /* + * synchronize_rcu here prevents mmu_notifier_release to + * return to exit_mmap (which would proceed freeing all pages + * in the mm) until the ->release method returns, if it was + * invoked by mmu_notifier_unregister. + * + * The mmu_notifier_mm can't go away from under us because one + * mm_count is hold by exit_mmap. + */ + synchronize_rcu(); +} + +/* + * If no young bitflag is supported by the hardware, ->clear_flush_young can + * unmap the address and return 1 or 0 depending if the mapping previously + * existed or not. + */ +int __mmu_notifier_clear_flush_young(struct mm_struct *mm, + unsigned long address) +{ + struct mmu_notifier *mn; + struct hlist_node *n; + int young = 0; + + rcu_read_lock(); + hlist_for_each_entry_rcu(mn, n, &mm->mmu_notifier_mm->list, hlist) { + if (mn->ops->clear_flush_young) + young |= mn->ops->clear_flush_young(mn, mm, address); + } + rcu_read_unlock(); + + return young; +} + +void __mmu_notifier_invalidate_page(struct mm_struct *mm, + unsigned long address) +{ + struct mmu_notifier *mn; + struct hlist_node *n; + + rcu_read_lock(); + hlist_for_each_entry_rcu(mn, n, &mm->mmu_notifier_mm->list, hlist) { + if (mn->ops->invalidate_page) + mn->ops->invalidate_page(mn, mm, address); + } + rcu_read_unlock(); +} + +void __mmu_notifier_invalidate_range_start(struct mm_struct *mm, + unsigned long start, unsigned long end) +{ + struct mmu_notifier *mn; + struct hlist_node *n; + + rcu_read_lock(); + hlist_for_each_entry_rcu(mn, n, &mm->mmu_notifier_mm->list, hlist) { + if (mn->ops->invalidate_range_start) + mn->ops->invalidate_range_start(mn, mm, start, end); + } + rcu_read_unlock(); +} + +void __mmu_notifier_invalidate_range_end(struct mm_struct *mm, + unsigned long start, unsigned long end) +{ + struct mmu_notifier *mn; + struct hlist_node *n; + + rcu_read_lock(); + hlist_for_each_entry_rcu(mn, n, &mm->mmu_notifier_mm->list, hlist) { + if (mn->ops->invalidate_range_end) + mn->ops->invalidate_range_end(mn, mm, start, end); + } + rcu_read_unlock(); +} + +static int do_mmu_notifier_register(struct mmu_notifier *mn, + struct mm_struct *mm, + int take_mmap_sem) +{ + struct mmu_notifier_mm *mmu_notifier_mm; + int ret; + + BUG_ON(atomic_read(&mm->mm_users) <= 0); + + ret = -ENOMEM; + mmu_notifier_mm = kmalloc(sizeof(struct mmu_notifier_mm), GFP_KERNEL); + if (unlikely(!mmu_notifier_mm)) + goto out; + + if (take_mmap_sem) + down_write(&mm->mmap_sem); + ret = mm_take_all_locks(mm); + if (unlikely(ret)) + goto out_cleanup; + + if (!mm_has_notifiers(mm)) { + INIT_HLIST_HEAD(&mmu_notifier_mm->list); + spin_lock_init(&mmu_notifier_mm->lock); + mm->mmu_notifier_mm = mmu_notifier_mm; + mmu_notifier_mm = NULL; + } + atomic_inc(&mm->mm_count); + + /* + * Serialize the update against mmu_notifier_unregister. A + * side note: mmu_notifier_release can't run concurrently with + * us because we hold the mm_users pin (either implicitly as + * current->mm or explicitly with get_task_mm() or similar). + * We can't race against any other mmu notifier method either + * thanks to mm_take_all_locks(). + */ + spin_lock(&mm->mmu_notifier_mm->lock); + hlist_add_head(&mn->hlist, &mm->mmu_notifier_mm->list); + spin_unlock(&mm->mmu_notifier_mm->lock); + + mm_drop_all_locks(mm); +out_cleanup: + if (take_mmap_sem) + up_write(&mm->mmap_sem); + /* kfree() does nothing if mmu_notifier_mm is NULL */ + kfree(mmu_notifier_mm); +out: + BUG_ON(atomic_read(&mm->mm_users) <= 0); + return ret; +} + +/* + * Must not hold mmap_sem nor any other VM related lock when calling + * this registration function. Must also ensure mm_users can't go down + * to zero while this runs to avoid races with mmu_notifier_release, + * so mm has to be current->mm or the mm should be pinned safely such + * as with get_task_mm(). If the mm is not current->mm, the mm_users + * pin should be released by calling mmput after mmu_notifier_register + * returns. mmu_notifier_unregister must be always called to + * unregister the notifier. mm_count is automatically pinned to allow + * mmu_notifier_unregister to safely run at any time later, before or + * after exit_mmap. ->release will always be called before exit_mmap + * frees the pages. + */ +int mmu_notifier_register(struct mmu_notifier *mn, struct mm_struct *mm) +{ + return do_mmu_notifier_register(mn, mm, 1); +} +EXPORT_SYMBOL_GPL(mmu_notifier_register); + +/* + * Same as mmu_notifier_register but here the caller must hold the + * mmap_sem in write mode. + */ +int __mmu_notifier_register(struct mmu_notifier *mn, struct mm_struct *mm) +{ + return do_mmu_notifier_register(mn, mm, 0); +} +EXPORT_SYMBOL_GPL(__mmu_notifier_register); + +/* this is called after the last mmu_notifier_unregister() returned */ +void __mmu_notifier_mm_destroy(struct mm_struct *mm) +{ + BUG_ON(!hlist_empty(&mm->mmu_notifier_mm->list)); + kfree(mm->mmu_notifier_mm); + mm->mmu_notifier_mm = LIST_POISON1; /* debug */ +} + +/* + * This releases the mm_count pin automatically and frees the mm + * structure if it was the last user of it. It serializes against + * running mmu notifiers with RCU and against mmu_notifier_unregister + * with the unregister lock + RCU. All sptes must be dropped before + * calling mmu_notifier_unregister. ->release or any other notifier + * method may be invoked concurrently with mmu_notifier_unregister, + * and only after mmu_notifier_unregister returned we're guaranteed + * that ->release or any other method can't run anymore. + */ +void mmu_notifier_unregister(struct mmu_notifier *mn, struct mm_struct *mm) +{ + BUG_ON(atomic_read(&mm->mm_count) <= 0); + + spin_lock(&mm->mmu_notifier_mm->lock); + if (!hlist_unhashed(&mn->hlist)) { + hlist_del_rcu(&mn->hlist); + + /* + * RCU here will force exit_mmap to wait ->release to finish + * before freeing the pages. + */ + rcu_read_lock(); + spin_unlock(&mm->mmu_notifier_mm->lock); + /* + * exit_mmap will block in mmu_notifier_release to + * guarantee ->release is called before freeing the + * pages. + */ + if (mn->ops->release) + mn->ops->release(mn, mm); + rcu_read_unlock(); + } else + spin_unlock(&mm->mmu_notifier_mm->lock); + + /* + * Wait any running method to finish, of course including + * ->release if it was run by mmu_notifier_relase instead of us. + */ + synchronize_rcu(); + + BUG_ON(atomic_read(&mm->mm_count) <= 0); + + mmdrop(mm); +} +EXPORT_SYMBOL_GPL(mmu_notifier_unregister); diff --git a/mm/mprotect.c b/mm/mprotect.c index abd645a3b0a0..fded06f923f4 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -203,10 +204,12 @@ success: dirty_accountable = 1; } + mmu_notifier_invalidate_range_start(mm, start, end); if (is_vm_hugetlb_page(vma)) hugetlb_change_protection(vma, start, end, vma->vm_page_prot); else change_protection(vma, start, end, vma->vm_page_prot, dirty_accountable); + mmu_notifier_invalidate_range_end(mm, start, end); vm_stat_account(mm, oldflags, vma->vm_file, -nrpages); vm_stat_account(mm, newflags, vma->vm_file, nrpages); return 0; diff --git a/mm/mremap.c b/mm/mremap.c index 08e3c7f2bd15..1a7743923c8c 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include @@ -74,7 +75,11 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd, struct mm_struct *mm = vma->vm_mm; pte_t *old_pte, *new_pte, pte; spinlock_t *old_ptl, *new_ptl; + unsigned long old_start; + old_start = old_addr; + mmu_notifier_invalidate_range_start(vma->vm_mm, + old_start, old_end); if (vma->vm_file) { /* * Subtle point from Rajesh Venkatasubramanian: before @@ -116,6 +121,7 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd, pte_unmap_unlock(old_pte - 1, old_ptl); if (mapping) spin_unlock(&mapping->i_mmap_lock); + mmu_notifier_invalidate_range_end(vma->vm_mm, old_start, old_end); } #define LATENCY_LIMIT (64 * PAGE_SIZE) diff --git a/mm/rmap.c b/mm/rmap.c index 39ae5a9bf382..99bc3f9cd796 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -49,6 +49,7 @@ #include #include #include +#include #include @@ -287,7 +288,7 @@ static int page_referenced_one(struct page *page, if (vma->vm_flags & VM_LOCKED) { referenced++; *mapcount = 1; /* break early from loop */ - } else if (ptep_clear_flush_young(vma, address, pte)) + } else if (ptep_clear_flush_young_notify(vma, address, pte)) referenced++; /* Pretend the page is referenced if the task has the @@ -457,7 +458,7 @@ static int page_mkclean_one(struct page *page, struct vm_area_struct *vma) pte_t entry; flush_cache_page(vma, address, pte_pfn(*pte)); - entry = ptep_clear_flush(vma, address, pte); + entry = ptep_clear_flush_notify(vma, address, pte); entry = pte_wrprotect(entry); entry = pte_mkclean(entry); set_pte_at(mm, address, pte, entry); @@ -705,14 +706,14 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, * skipped over this mm) then we should reactivate it. */ if (!migration && ((vma->vm_flags & VM_LOCKED) || - (ptep_clear_flush_young(vma, address, pte)))) { + (ptep_clear_flush_young_notify(vma, address, pte)))) { ret = SWAP_FAIL; goto out_unmap; } /* Nuke the page table entry. */ flush_cache_page(vma, address, page_to_pfn(page)); - pteval = ptep_clear_flush(vma, address, pte); + pteval = ptep_clear_flush_notify(vma, address, pte); /* Move the dirty bit to the physical page now the pte is gone. */ if (pte_dirty(pteval)) @@ -837,12 +838,12 @@ static void try_to_unmap_cluster(unsigned long cursor, page = vm_normal_page(vma, address, *pte); BUG_ON(!page || PageAnon(page)); - if (ptep_clear_flush_young(vma, address, pte)) + if (ptep_clear_flush_young_notify(vma, address, pte)) continue; /* Nuke the page table entry. */ flush_cache_page(vma, address, pte_pfn(*pte)); - pteval = ptep_clear_flush(vma, address, pte); + pteval = ptep_clear_flush_notify(vma, address, pte); /* If nonlinear, store the file page offset in the pte. */ if (page->index != linear_page_index(vma, address)) -- cgit v1.3-18-gd494