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authorLinus Torvalds <torvalds@linux-foundation.org>2019-03-07 13:27:53 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-03-07 13:27:53 -0800
commitdd1c3ed76f26504621b5ce08b894666aafa38e47 (patch)
treef879aefbbd7871733bc616cb7f73dd5ffca53f44 /arch/xtensa
parentMerge tag 'powerpc-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux (diff)
parentxtensa: simplify trap_init (diff)
downloadlinux-dev-dd1c3ed76f26504621b5ce08b894666aafa38e47.tar.xz
linux-dev-dd1c3ed76f26504621b5ce08b894666aafa38e47.zip
Merge tag 'xtensa-20190307' of git://github.com/jcmvbkbc/linux-xtensa
Pull xtensa updates from Max Filippov: - use generic spinlock/rwlock implementations - clean up IPI processing - document boot parameters passing to the kernel - fix get_wchan - various cleanups in time.c, process.c, traps.c and thread_info.h * tag 'xtensa-20190307' of git://github.com/jcmvbkbc/linux-xtensa: xtensa: simplify trap_init xtensa: drop unused definitions xtensa: fix get_wchan xtensa: use generic spinlock/rwlock implementation xtensa: provide xchg for sizes 1 and 2 xtensa: clean up arch/xtensa/kernel/time.c xtensa: SMP: rework IPI processing xtensa: document boot parameter passing
Diffstat (limited to 'arch/xtensa')
-rw-r--r--arch/xtensa/Kconfig2
-rw-r--r--arch/xtensa/include/asm/Kbuild2
-rw-r--r--arch/xtensa/include/asm/cmpxchg.h36
-rw-r--r--arch/xtensa/include/asm/spinlock.h185
-rw-r--r--arch/xtensa/include/asm/spinlock_types.h15
-rw-r--r--arch/xtensa/include/asm/thread_info.h9
-rw-r--r--arch/xtensa/kernel/process.c6
-rw-r--r--arch/xtensa/kernel/smp.c38
-rw-r--r--arch/xtensa/kernel/time.c53
-rw-r--r--arch/xtensa/kernel/traps.c5
10 files changed, 94 insertions, 257 deletions
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 963986a48c62..bacf87ee7975 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -5,6 +5,8 @@ config XTENSA
select ARCH_HAS_SYNC_DMA_FOR_CPU
select ARCH_HAS_SYNC_DMA_FOR_DEVICE
select ARCH_NO_COHERENT_DMA_MMAP if !MMU
+ select ARCH_USE_QUEUED_RWLOCKS
+ select ARCH_USE_QUEUED_SPINLOCKS
select ARCH_WANT_FRAME_POINTERS
select ARCH_WANT_IPC_PARSE_VERSION
select BUILDTIME_EXTABLE_SORT
diff --git a/arch/xtensa/include/asm/Kbuild b/arch/xtensa/include/asm/Kbuild
index 809f39ce08c0..d939e13e8d84 100644
--- a/arch/xtensa/include/asm/Kbuild
+++ b/arch/xtensa/include/asm/Kbuild
@@ -23,6 +23,8 @@ generic-y += mm-arch-hooks.h
generic-y += param.h
generic-y += percpu.h
generic-y += preempt.h
+generic-y += qrwlock.h
+generic-y += qspinlock.h
generic-y += rwsem.h
generic-y += sections.h
generic-y += socket.h
diff --git a/arch/xtensa/include/asm/cmpxchg.h b/arch/xtensa/include/asm/cmpxchg.h
index 201e9009efd8..22a10c715c1f 100644
--- a/arch/xtensa/include/asm/cmpxchg.h
+++ b/arch/xtensa/include/asm/cmpxchg.h
@@ -13,6 +13,7 @@
#ifndef __ASSEMBLY__
+#include <linux/bits.h>
#include <linux/stringify.h>
/*
@@ -138,6 +139,28 @@ static inline unsigned long xchg_u32(volatile int * m, unsigned long val)
#define xchg(ptr,x) \
((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
+static inline u32 xchg_small(volatile void *ptr, u32 x, int size)
+{
+ int off = (unsigned long)ptr % sizeof(u32);
+ volatile u32 *p = ptr - off;
+#ifdef __BIG_ENDIAN
+ int bitoff = (sizeof(u32) - size - off) * BITS_PER_BYTE;
+#else
+ int bitoff = off * BITS_PER_BYTE;
+#endif
+ u32 bitmask = ((0x1 << size * BITS_PER_BYTE) - 1) << bitoff;
+ u32 oldv, newv;
+ u32 ret;
+
+ do {
+ oldv = READ_ONCE(*p);
+ ret = (oldv & bitmask) >> bitoff;
+ newv = (oldv & ~bitmask) | (x << bitoff);
+ } while (__cmpxchg_u32(p, oldv, newv) != oldv);
+
+ return ret;
+}
+
/*
* This only works if the compiler isn't horribly bad at optimizing.
* gcc-2.5.8 reportedly can't handle this, but I define that one to
@@ -150,11 +173,16 @@ static __inline__ unsigned long
__xchg(unsigned long x, volatile void * ptr, int size)
{
switch (size) {
- case 4:
- return xchg_u32(ptr, x);
+ case 1:
+ return xchg_small(ptr, x, 1);
+ case 2:
+ return xchg_small(ptr, x, 2);
+ case 4:
+ return xchg_u32(ptr, x);
+ default:
+ __xchg_called_with_bad_pointer();
+ return x;
}
- __xchg_called_with_bad_pointer();
- return x;
}
#endif /* __ASSEMBLY__ */
diff --git a/arch/xtensa/include/asm/spinlock.h b/arch/xtensa/include/asm/spinlock.h
index c6e1290dcbb7..584b0de6f2ca 100644
--- a/arch/xtensa/include/asm/spinlock.h
+++ b/arch/xtensa/include/asm/spinlock.h
@@ -12,188 +12,9 @@
#define _XTENSA_SPINLOCK_H
#include <asm/barrier.h>
-#include <asm/processor.h>
+#include <asm/qrwlock.h>
+#include <asm/qspinlock.h>
-/*
- * spinlock
- *
- * There is at most one owner of a spinlock. There are not different
- * types of spinlock owners like there are for rwlocks (see below).
- *
- * When trying to obtain a spinlock, the function "spins" forever, or busy-
- * waits, until the lock is obtained. When spinning, presumably some other
- * owner will soon give up the spinlock making it available to others. Use
- * the trylock functions to avoid spinning forever.
- *
- * possible values:
- *
- * 0 nobody owns the spinlock
- * 1 somebody owns the spinlock
- */
-
-#define arch_spin_is_locked(x) ((x)->slock != 0)
-
-static inline void arch_spin_lock(arch_spinlock_t *lock)
-{
- unsigned long tmp;
-
- __asm__ __volatile__(
- " movi %0, 0\n"
- " wsr %0, scompare1\n"
- "1: movi %0, 1\n"
- " s32c1i %0, %1, 0\n"
- " bnez %0, 1b\n"
- : "=&a" (tmp)
- : "a" (&lock->slock)
- : "memory");
-}
-
-/* Returns 1 if the lock is obtained, 0 otherwise. */
-
-static inline int arch_spin_trylock(arch_spinlock_t *lock)
-{
- unsigned long tmp;
-
- __asm__ __volatile__(
- " movi %0, 0\n"
- " wsr %0, scompare1\n"
- " movi %0, 1\n"
- " s32c1i %0, %1, 0\n"
- : "=&a" (tmp)
- : "a" (&lock->slock)
- : "memory");
-
- return tmp == 0 ? 1 : 0;
-}
-
-static inline void arch_spin_unlock(arch_spinlock_t *lock)
-{
- unsigned long tmp;
-
- __asm__ __volatile__(
- " movi %0, 0\n"
- " s32ri %0, %1, 0\n"
- : "=&a" (tmp)
- : "a" (&lock->slock)
- : "memory");
-}
-
-/*
- * rwlock
- *
- * Read-write locks are really a more flexible spinlock. They allow
- * multiple readers but only one writer. Write ownership is exclusive
- * (i.e., all other readers and writers are blocked from ownership while
- * there is a write owner). These rwlocks are unfair to writers. Writers
- * can be starved for an indefinite time by readers.
- *
- * possible values:
- *
- * 0 nobody owns the rwlock
- * >0 one or more readers own the rwlock
- * (the positive value is the actual number of readers)
- * 0x80000000 one writer owns the rwlock, no other writers, no readers
- */
-
-static inline void arch_write_lock(arch_rwlock_t *rw)
-{
- unsigned long tmp;
-
- __asm__ __volatile__(
- " movi %0, 0\n"
- " wsr %0, scompare1\n"
- "1: movi %0, 1\n"
- " slli %0, %0, 31\n"
- " s32c1i %0, %1, 0\n"
- " bnez %0, 1b\n"
- : "=&a" (tmp)
- : "a" (&rw->lock)
- : "memory");
-}
-
-/* Returns 1 if the lock is obtained, 0 otherwise. */
-
-static inline int arch_write_trylock(arch_rwlock_t *rw)
-{
- unsigned long tmp;
-
- __asm__ __volatile__(
- " movi %0, 0\n"
- " wsr %0, scompare1\n"
- " movi %0, 1\n"
- " slli %0, %0, 31\n"
- " s32c1i %0, %1, 0\n"
- : "=&a" (tmp)
- : "a" (&rw->lock)
- : "memory");
-
- return tmp == 0 ? 1 : 0;
-}
-
-static inline void arch_write_unlock(arch_rwlock_t *rw)
-{
- unsigned long tmp;
-
- __asm__ __volatile__(
- " movi %0, 0\n"
- " s32ri %0, %1, 0\n"
- : "=&a" (tmp)
- : "a" (&rw->lock)
- : "memory");
-}
-
-static inline void arch_read_lock(arch_rwlock_t *rw)
-{
- unsigned long tmp;
- unsigned long result;
-
- __asm__ __volatile__(
- "1: l32i %1, %2, 0\n"
- " bltz %1, 1b\n"
- " wsr %1, scompare1\n"
- " addi %0, %1, 1\n"
- " s32c1i %0, %2, 0\n"
- " bne %0, %1, 1b\n"
- : "=&a" (result), "=&a" (tmp)
- : "a" (&rw->lock)
- : "memory");
-}
-
-/* Returns 1 if the lock is obtained, 0 otherwise. */
-
-static inline int arch_read_trylock(arch_rwlock_t *rw)
-{
- unsigned long result;
- unsigned long tmp;
-
- __asm__ __volatile__(
- " l32i %1, %2, 0\n"
- " addi %0, %1, 1\n"
- " bltz %0, 1f\n"
- " wsr %1, scompare1\n"
- " s32c1i %0, %2, 0\n"
- " sub %0, %0, %1\n"
- "1:\n"
- : "=&a" (result), "=&a" (tmp)
- : "a" (&rw->lock)
- : "memory");
-
- return result == 0;
-}
-
-static inline void arch_read_unlock(arch_rwlock_t *rw)
-{
- unsigned long tmp1, tmp2;
-
- __asm__ __volatile__(
- "1: l32i %1, %2, 0\n"
- " addi %0, %1, -1\n"
- " wsr %1, scompare1\n"
- " s32c1i %0, %2, 0\n"
- " bne %0, %1, 1b\n"
- : "=&a" (tmp1), "=&a" (tmp2)
- : "a" (&rw->lock)
- : "memory");
-}
+#define smp_mb__after_spinlock() smp_mb()
#endif /* _XTENSA_SPINLOCK_H */
diff --git a/arch/xtensa/include/asm/spinlock_types.h b/arch/xtensa/include/asm/spinlock_types.h
index bb1fe6c1816e..64c9389254f1 100644
--- a/arch/xtensa/include/asm/spinlock_types.h
+++ b/arch/xtensa/include/asm/spinlock_types.h
@@ -2,20 +2,11 @@
#ifndef __ASM_SPINLOCK_TYPES_H
#define __ASM_SPINLOCK_TYPES_H
-#ifndef __LINUX_SPINLOCK_TYPES_H
+#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__ASM_SPINLOCK_H)
# error "please don't include this file directly"
#endif
-typedef struct {
- volatile unsigned int slock;
-} arch_spinlock_t;
-
-#define __ARCH_SPIN_LOCK_UNLOCKED { 0 }
-
-typedef struct {
- volatile unsigned int lock;
-} arch_rwlock_t;
-
-#define __ARCH_RW_LOCK_UNLOCKED { 0 }
+#include <asm-generic/qspinlock_types.h>
+#include <asm-generic/qrwlock_types.h>
#endif
diff --git a/arch/xtensa/include/asm/thread_info.h b/arch/xtensa/include/asm/thread_info.h
index f333f10a7650..f092cc3f4e66 100644
--- a/arch/xtensa/include/asm/thread_info.h
+++ b/arch/xtensa/include/asm/thread_info.h
@@ -121,15 +121,6 @@ static inline struct thread_info *current_thread_info(void)
#define _TIF_WORK_MASK (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
_TIF_SYSCALL_TRACEPOINT)
-/*
- * Thread-synchronous status.
- *
- * This is different from the flags in that nobody else
- * ever touches our thread-synchronous status, so we don't
- * have to worry about atomic accesses.
- */
-#define TS_USEDFPU 0x0001 /* FPU was used by this task this quantum (SMP) */
-
#define THREAD_SIZE KERNEL_STACK_SIZE
#define THREAD_SIZE_ORDER (KERNEL_STACK_SHIFT - PAGE_SHIFT)
diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c
index 74969a437a37..db278a9e80c7 100644
--- a/arch/xtensa/kernel/process.c
+++ b/arch/xtensa/kernel/process.c
@@ -52,8 +52,6 @@
extern void ret_from_fork(void);
extern void ret_from_kernel_thread(void);
-struct task_struct *current_set[NR_CPUS] = {&init_task, };
-
void (*pm_power_off)(void) = NULL;
EXPORT_SYMBOL(pm_power_off);
@@ -321,8 +319,8 @@ unsigned long get_wchan(struct task_struct *p)
/* Stack layout: sp-4: ra, sp-3: sp' */
- pc = MAKE_PC_FROM_RA(*(unsigned long*)sp - 4, sp);
- sp = *(unsigned long *)sp - 3;
+ pc = MAKE_PC_FROM_RA(SPILL_SLOT(sp, 0), sp);
+ sp = SPILL_SLOT(sp, 1);
} while (count++ < 16);
return 0;
}
diff --git a/arch/xtensa/kernel/smp.c b/arch/xtensa/kernel/smp.c
index be1f280c322c..3699d6d3e479 100644
--- a/arch/xtensa/kernel/smp.c
+++ b/arch/xtensa/kernel/smp.c
@@ -372,8 +372,7 @@ static void send_ipi_message(const struct cpumask *callmask,
unsigned long mask = 0;
for_each_cpu(index, callmask)
- if (index != smp_processor_id())
- mask |= 1 << index;
+ mask |= 1 << index;
set_er(mask, MIPISET(msg_id));
}
@@ -412,22 +411,31 @@ irqreturn_t ipi_interrupt(int irq, void *dev_id)
{
unsigned int cpu = smp_processor_id();
struct ipi_data *ipi = &per_cpu(ipi_data, cpu);
- unsigned int msg;
- unsigned i;
- msg = get_er(MIPICAUSE(cpu));
- for (i = 0; i < IPI_MAX; i++)
- if (msg & (1 << i)) {
- set_er(1 << i, MIPICAUSE(cpu));
- ++ipi->ipi_count[i];
+ for (;;) {
+ unsigned int msg;
+
+ msg = get_er(MIPICAUSE(cpu));
+ set_er(msg, MIPICAUSE(cpu));
+
+ if (!msg)
+ break;
+
+ if (msg & (1 << IPI_CALL_FUNC)) {
+ ++ipi->ipi_count[IPI_CALL_FUNC];
+ generic_smp_call_function_interrupt();
}
- if (msg & (1 << IPI_RESCHEDULE))
- scheduler_ipi();
- if (msg & (1 << IPI_CALL_FUNC))
- generic_smp_call_function_interrupt();
- if (msg & (1 << IPI_CPU_STOP))
- ipi_cpu_stop(cpu);
+ if (msg & (1 << IPI_RESCHEDULE)) {
+ ++ipi->ipi_count[IPI_RESCHEDULE];
+ scheduler_ipi();
+ }
+
+ if (msg & (1 << IPI_CPU_STOP)) {
+ ++ipi->ipi_count[IPI_CPU_STOP];
+ ipi_cpu_stop(cpu);
+ }
+ }
return IRQ_HANDLED;
}
diff --git a/arch/xtensa/kernel/time.c b/arch/xtensa/kernel/time.c
index 378186b5eb40..69db8c93c1f9 100644
--- a/arch/xtensa/kernel/time.c
+++ b/arch/xtensa/kernel/time.c
@@ -52,14 +52,11 @@ static struct clocksource ccount_clocksource = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
-static int ccount_timer_set_next_event(unsigned long delta,
- struct clock_event_device *dev);
struct ccount_timer {
struct clock_event_device evt;
int irq_enabled;
char name[24];
};
-static DEFINE_PER_CPU(struct ccount_timer, ccount_timer);
static int ccount_timer_set_next_event(unsigned long delta,
struct clock_event_device *dev)
@@ -107,7 +104,30 @@ static int ccount_timer_set_oneshot(struct clock_event_device *evt)
return 0;
}
-static irqreturn_t timer_interrupt(int irq, void *dev_id);
+static DEFINE_PER_CPU(struct ccount_timer, ccount_timer) = {
+ .evt = {
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 300,
+ .set_next_event = ccount_timer_set_next_event,
+ .set_state_shutdown = ccount_timer_shutdown,
+ .set_state_oneshot = ccount_timer_set_oneshot,
+ .tick_resume = ccount_timer_set_oneshot,
+ },
+};
+
+static irqreturn_t timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = &this_cpu_ptr(&ccount_timer)->evt;
+
+ set_linux_timer(get_linux_timer());
+ evt->event_handler(evt);
+
+ /* Allow platform to do something useful (Wdog). */
+ platform_heartbeat();
+
+ return IRQ_HANDLED;
+}
+
static struct irqaction timer_irqaction = {
.handler = timer_interrupt,
.flags = IRQF_TIMER,
@@ -120,14 +140,8 @@ void local_timer_setup(unsigned cpu)
struct clock_event_device *clockevent = &timer->evt;
timer->irq_enabled = 1;
- clockevent->name = timer->name;
snprintf(timer->name, sizeof(timer->name), "ccount_clockevent_%u", cpu);
- clockevent->features = CLOCK_EVT_FEAT_ONESHOT;
- clockevent->rating = 300;
- clockevent->set_next_event = ccount_timer_set_next_event;
- clockevent->set_state_shutdown = ccount_timer_shutdown;
- clockevent->set_state_oneshot = ccount_timer_set_oneshot;
- clockevent->tick_resume = ccount_timer_set_oneshot;
+ clockevent->name = timer->name;
clockevent->cpumask = cpumask_of(cpu);
clockevent->irq = irq_create_mapping(NULL, LINUX_TIMER_INT);
if (WARN(!clockevent->irq, "error: can't map timer irq"))
@@ -190,23 +204,6 @@ void __init time_init(void)
timer_probe();
}
-/*
- * The timer interrupt is called HZ times per second.
- */
-
-irqreturn_t timer_interrupt(int irq, void *dev_id)
-{
- struct clock_event_device *evt = &this_cpu_ptr(&ccount_timer)->evt;
-
- set_linux_timer(get_linux_timer());
- evt->event_handler(evt);
-
- /* Allow platform to do something useful (Wdog). */
- platform_heartbeat();
-
- return IRQ_HANDLED;
-}
-
#ifndef CONFIG_GENERIC_CALIBRATE_DELAY
void calibrate_delay(void)
{
diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c
index e6fa55aa1ccb..454d53096bc9 100644
--- a/arch/xtensa/kernel/traps.c
+++ b/arch/xtensa/kernel/traps.c
@@ -420,16 +420,15 @@ void __init trap_init(void)
/* Setup specific handlers. */
for(i = 0; dispatch_init_table[i].cause >= 0; i++) {
-
int fast = dispatch_init_table[i].fast;
int cause = dispatch_init_table[i].cause;
void *handler = dispatch_init_table[i].handler;
if (fast == 0)
set_handler(default_handler, cause, handler);
- if (fast && fast & USER)
+ if ((fast & USER) != 0)
set_handler(fast_user_handler, cause, handler);
- if (fast && fast & KRNL)
+ if ((fast & KRNL) != 0)
set_handler(fast_kernel_handler, cause, handler);
}