From 9b130ad5bb8255ee8534d92d67e12b2a4887eacb Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Fri, 8 Sep 2017 16:14:18 -0700 Subject: treewide: make "nr_cpu_ids" unsigned First, number of CPUs can't be negative number. Second, different signnnedness leads to suboptimal code in the following cases: 1) kmalloc(nr_cpu_ids * sizeof(X)); "int" has to be sign extended to size_t. 2) while (loff_t *pos < nr_cpu_ids) MOVSXD is 1 byte longed than the same MOV. Other cases exist as well. Basically compiler is told that nr_cpu_ids can't be negative which can't be deduced if it is "int". Code savings on allyesconfig kernel: -3KB add/remove: 0/0 grow/shrink: 25/264 up/down: 261/-3631 (-3370) function old new delta coretemp_cpu_online 450 512 +62 rcu_init_one 1234 1272 +38 pci_device_probe 374 399 +25 ... pgdat_reclaimable_pages 628 556 -72 select_fallback_rq 446 369 -77 task_numa_find_cpu 1923 1807 -116 Link: http://lkml.kernel.org/r/20170819114959.GA30580@avx2 Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/arm64/kernel/smp.c | 2 +- arch/powerpc/kernel/paca.c | 2 +- arch/powerpc/kernel/setup-common.c | 2 +- arch/powerpc/sysdev/xive/native.c | 4 ++-- arch/tile/kernel/setup.c | 2 +- arch/x86/kernel/apic/apic.c | 2 +- arch/x86/kernel/setup_percpu.c | 2 +- arch/x86/kernel/smpboot.c | 2 +- 8 files changed, 9 insertions(+), 9 deletions(-) (limited to 'arch') diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index ffe089942ac4..9f7195a5773e 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -690,7 +690,7 @@ void __init smp_init_cpus(void) acpi_parse_gic_cpu_interface, 0); if (cpu_count > nr_cpu_ids) - pr_warn("Number of cores (%d) exceeds configured maximum of %d - clipping\n", + pr_warn("Number of cores (%d) exceeds configured maximum of %u - clipping\n", cpu_count, nr_cpu_ids); if (!bootcpu_valid) { diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c index 70f073d6c3b2..2ff2b8a19f71 100644 --- a/arch/powerpc/kernel/paca.c +++ b/arch/powerpc/kernel/paca.c @@ -224,7 +224,7 @@ void __init allocate_pacas(void) paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit)); memset(paca, 0, paca_size); - printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n", + printk(KERN_DEBUG "Allocated %u bytes for %u pacas at %p\n", paca_size, nr_cpu_ids, paca); allocate_lppacas(nr_cpu_ids, limit); diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c index 7de73589d8e2..0ac741fae90e 100644 --- a/arch/powerpc/kernel/setup-common.c +++ b/arch/powerpc/kernel/setup-common.c @@ -551,7 +551,7 @@ void __init smp_setup_cpu_maps(void) if (maxcpus > nr_cpu_ids) { printk(KERN_WARNING "Partition configured for %d cpus, " - "operating system maximum is %d.\n", + "operating system maximum is %u.\n", maxcpus, nr_cpu_ids); maxcpus = nr_cpu_ids; } else diff --git a/arch/powerpc/sysdev/xive/native.c b/arch/powerpc/sysdev/xive/native.c index 44f3a25ca630..ebc244b08d67 100644 --- a/arch/powerpc/sysdev/xive/native.c +++ b/arch/powerpc/sysdev/xive/native.c @@ -511,13 +511,13 @@ static bool xive_parse_provisioning(struct device_node *np) static void xive_native_setup_pools(void) { /* Allocate a pool big enough */ - pr_debug("XIVE: Allocating VP block for pool size %d\n", nr_cpu_ids); + pr_debug("XIVE: Allocating VP block for pool size %u\n", nr_cpu_ids); xive_pool_vps = xive_native_alloc_vp_block(nr_cpu_ids); if (WARN_ON(xive_pool_vps == XIVE_INVALID_VP)) pr_err("XIVE: Failed to allocate pool VP, KVM might not function\n"); - pr_debug("XIVE: Pool VPs allocated at 0x%x for %d max CPUs\n", + pr_debug("XIVE: Pool VPs allocated at 0x%x for %u max CPUs\n", xive_pool_vps, nr_cpu_ids); } diff --git a/arch/tile/kernel/setup.c b/arch/tile/kernel/setup.c index 443a70bccc1c..6becb96c60a0 100644 --- a/arch/tile/kernel/setup.c +++ b/arch/tile/kernel/setup.c @@ -1200,7 +1200,7 @@ static void __init validate_hv(void) * We use a struct cpumask for this, so it must be big enough. */ if ((smp_height * smp_width) > nr_cpu_ids) - early_panic("Hypervisor %d x %d grid too big for Linux NR_CPUS %d\n", + early_panic("Hypervisor %d x %d grid too big for Linux NR_CPUS %u\n", smp_height, smp_width, nr_cpu_ids); #endif diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 7834f73efbf1..8315e2f517a7 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -2097,7 +2097,7 @@ static int allocate_logical_cpuid(int apicid) /* Allocate a new cpuid. */ if (nr_logical_cpuids >= nr_cpu_ids) { - WARN_ONCE(1, "APIC: NR_CPUS/possible_cpus limit of %i reached. " + WARN_ONCE(1, "APIC: NR_CPUS/possible_cpus limit of %u reached. " "Processor %d/0x%x and the rest are ignored.\n", nr_cpu_ids, nr_logical_cpuids, apicid); return -EINVAL; diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index 6e8fcb6f7e1e..28dafed6c682 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -168,7 +168,7 @@ void __init setup_per_cpu_areas(void) unsigned long delta; int rc; - pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%d nr_node_ids:%d\n", + pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%u nr_node_ids:%d\n", NR_CPUS, nr_cpumask_bits, nr_cpu_ids, nr_node_ids); /* diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 54b9e89d4d6b..cd6622c3204e 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -1461,7 +1461,7 @@ __init void prefill_possible_map(void) /* nr_cpu_ids could be reduced via nr_cpus= */ if (possible > nr_cpu_ids) { - pr_warn("%d Processors exceeds NR_CPUS limit of %d\n", + pr_warn("%d Processors exceeds NR_CPUS limit of %u\n", possible, nr_cpu_ids); possible = nr_cpu_ids; } -- cgit v1.2.3-59-g8ed1b