From fe7de49f9d4e53f24ec9ef762a503f70b562341c Mon Sep 17 00:00:00 2001 From: KOSAKI Motohiro Date: Wed, 20 Oct 2010 16:01:12 -0700 Subject: sched: Make sched_param argument static in sched_setscheduler() callers Andrew Morton pointed out almost all sched_setscheduler() callers are using fixed parameters and can be converted to static. It reduces runtime memory use a little. Signed-off-by: KOSAKI Motohiro Reported-by: Andrew Morton Acked-by: James Morris Cc: Ingo Molnar Cc: Steven Rostedt Signed-off-by: Andrew Morton Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar --- kernel/watchdog.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/watchdog.c') diff --git a/kernel/watchdog.c b/kernel/watchdog.c index bafba687a6d..94ca779aa9c 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -307,7 +307,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) */ static int watchdog(void *unused) { - struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; + static struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; struct hrtimer *hrtimer = &__raw_get_cpu_var(watchdog_hrtimer); sched_setscheduler(current, SCHED_FIFO, ¶m); -- cgit v1.2.3-70-g09d2 From 004417a6d468e24399e383645c068b498eed84ad Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 25 Nov 2010 18:38:29 +0100 Subject: perf, arch: Cleanup perf-pmu init vs lockup-detector The perf hardware pmu got initialized at various points in the boot, some before early_initcall() some after (notably arch_initcall). The problem is that the NMI lockup detector is ran from early_initcall() and expects the hardware pmu to be present. Sanitize this by moving all architecture hardware pmu implementations to initialize at early_initcall() and move the lockup detector to an explicit initcall right after that. Cc: paulus Cc: davem Cc: Michael Cree Cc: Deng-Cheng Zhu Acked-by: Paul Mundt Acked-by: Will Deacon Signed-off-by: Peter Zijlstra LKML-Reference: <1290707759.2145.119.camel@laptop> Signed-off-by: Ingo Molnar --- arch/alpha/include/asm/perf_event.h | 6 ------ arch/alpha/kernel/irq_alpha.c | 2 -- arch/alpha/kernel/perf_event.c | 9 ++++++--- arch/arm/kernel/perf_event.c | 2 +- arch/mips/kernel/perf_event_mipsxx.c | 2 +- arch/powerpc/kernel/e500-pmu.c | 2 +- arch/powerpc/kernel/mpc7450-pmu.c | 2 +- arch/powerpc/kernel/power4-pmu.c | 2 +- arch/powerpc/kernel/power5+-pmu.c | 2 +- arch/powerpc/kernel/power5-pmu.c | 2 +- arch/powerpc/kernel/power6-pmu.c | 2 +- arch/powerpc/kernel/power7-pmu.c | 2 +- arch/powerpc/kernel/ppc970-pmu.c | 2 +- arch/sh/kernel/cpu/sh4/perf_event.c | 2 +- arch/sh/kernel/cpu/sh4a/perf_event.c | 2 +- arch/sparc/include/asm/perf_event.h | 4 ---- arch/sparc/kernel/nmi.c | 2 -- arch/sparc/kernel/perf_event.c | 7 +++++-- arch/x86/include/asm/perf_event.h | 2 -- arch/x86/kernel/cpu/common.c | 1 - arch/x86/kernel/cpu/perf_event.c | 11 +++++++---- include/linux/sched.h | 4 ++++ init/main.c | 1 + kernel/watchdog.c | 7 +++---- 24 files changed, 38 insertions(+), 42 deletions(-) (limited to 'kernel/watchdog.c') diff --git a/arch/alpha/include/asm/perf_event.h b/arch/alpha/include/asm/perf_event.h index fe792ca818f..5996e7a6757 100644 --- a/arch/alpha/include/asm/perf_event.h +++ b/arch/alpha/include/asm/perf_event.h @@ -1,10 +1,4 @@ #ifndef __ASM_ALPHA_PERF_EVENT_H #define __ASM_ALPHA_PERF_EVENT_H -#ifdef CONFIG_PERF_EVENTS -extern void init_hw_perf_events(void); -#else -static inline void init_hw_perf_events(void) { } -#endif - #endif /* __ASM_ALPHA_PERF_EVENT_H */ diff --git a/arch/alpha/kernel/irq_alpha.c b/arch/alpha/kernel/irq_alpha.c index 5f77afb88e8..4c8bb374eb0 100644 --- a/arch/alpha/kernel/irq_alpha.c +++ b/arch/alpha/kernel/irq_alpha.c @@ -112,8 +112,6 @@ init_IRQ(void) wrent(entInt, 0); alpha_mv.init_irq(); - - init_hw_perf_events(); } /* diff --git a/arch/alpha/kernel/perf_event.c b/arch/alpha/kernel/perf_event.c index 1cc49683fb6..3283059b6e8 100644 --- a/arch/alpha/kernel/perf_event.c +++ b/arch/alpha/kernel/perf_event.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include @@ -863,13 +864,13 @@ static void alpha_perf_event_irq_handler(unsigned long la_ptr, /* * Init call to initialise performance events at kernel startup. */ -void __init init_hw_perf_events(void) +int __init init_hw_perf_events(void) { pr_info("Performance events: "); if (!supported_cpu()) { pr_cont("No support for your CPU.\n"); - return; + return 0; } pr_cont("Supported CPU type!\n"); @@ -882,5 +883,7 @@ void __init init_hw_perf_events(void) alpha_pmu = &ev67_pmu; perf_pmu_register(&pmu); -} + return 0; +} +early_initcall(init_hw_perf_events); diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 07a50357492..d45f70e5f2e 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -3038,7 +3038,7 @@ init_hw_perf_events(void) return 0; } -arch_initcall(init_hw_perf_events); +early_initcall(init_hw_perf_events); /* * Callchain handling code. diff --git a/arch/mips/kernel/perf_event_mipsxx.c b/arch/mips/kernel/perf_event_mipsxx.c index 5c7c6fc0756..183e0d22666 100644 --- a/arch/mips/kernel/perf_event_mipsxx.c +++ b/arch/mips/kernel/perf_event_mipsxx.c @@ -1047,6 +1047,6 @@ init_hw_perf_events(void) return 0; } -arch_initcall(init_hw_perf_events); +early_initcall(init_hw_perf_events); #endif /* defined(CONFIG_CPU_MIPS32)... */ diff --git a/arch/powerpc/kernel/e500-pmu.c b/arch/powerpc/kernel/e500-pmu.c index 7c07de0d894..b150b510510 100644 --- a/arch/powerpc/kernel/e500-pmu.c +++ b/arch/powerpc/kernel/e500-pmu.c @@ -126,4 +126,4 @@ static int init_e500_pmu(void) return register_fsl_emb_pmu(&e500_pmu); } -arch_initcall(init_e500_pmu); +early_initcall(init_e500_pmu); diff --git a/arch/powerpc/kernel/mpc7450-pmu.c b/arch/powerpc/kernel/mpc7450-pmu.c index 09d72028f31..2cc5e0301d0 100644 --- a/arch/powerpc/kernel/mpc7450-pmu.c +++ b/arch/powerpc/kernel/mpc7450-pmu.c @@ -414,4 +414,4 @@ static int init_mpc7450_pmu(void) return register_power_pmu(&mpc7450_pmu); } -arch_initcall(init_mpc7450_pmu); +early_initcall(init_mpc7450_pmu); diff --git a/arch/powerpc/kernel/power4-pmu.c b/arch/powerpc/kernel/power4-pmu.c index 2a361cdda63..ead8b3c2649 100644 --- a/arch/powerpc/kernel/power4-pmu.c +++ b/arch/powerpc/kernel/power4-pmu.c @@ -613,4 +613,4 @@ static int init_power4_pmu(void) return register_power_pmu(&power4_pmu); } -arch_initcall(init_power4_pmu); +early_initcall(init_power4_pmu); diff --git a/arch/powerpc/kernel/power5+-pmu.c b/arch/powerpc/kernel/power5+-pmu.c index 199de527d41..eca0ac595cb 100644 --- a/arch/powerpc/kernel/power5+-pmu.c +++ b/arch/powerpc/kernel/power5+-pmu.c @@ -682,4 +682,4 @@ static int init_power5p_pmu(void) return register_power_pmu(&power5p_pmu); } -arch_initcall(init_power5p_pmu); +early_initcall(init_power5p_pmu); diff --git a/arch/powerpc/kernel/power5-pmu.c b/arch/powerpc/kernel/power5-pmu.c index 98b6a729a9d..d5ff0f64a5e 100644 --- a/arch/powerpc/kernel/power5-pmu.c +++ b/arch/powerpc/kernel/power5-pmu.c @@ -621,4 +621,4 @@ static int init_power5_pmu(void) return register_power_pmu(&power5_pmu); } -arch_initcall(init_power5_pmu); +early_initcall(init_power5_pmu); diff --git a/arch/powerpc/kernel/power6-pmu.c b/arch/powerpc/kernel/power6-pmu.c index 84a607bda8f..31603927e37 100644 --- a/arch/powerpc/kernel/power6-pmu.c +++ b/arch/powerpc/kernel/power6-pmu.c @@ -544,4 +544,4 @@ static int init_power6_pmu(void) return register_power_pmu(&power6_pmu); } -arch_initcall(init_power6_pmu); +early_initcall(init_power6_pmu); diff --git a/arch/powerpc/kernel/power7-pmu.c b/arch/powerpc/kernel/power7-pmu.c index 852f7b7f6b4..593740fcb79 100644 --- a/arch/powerpc/kernel/power7-pmu.c +++ b/arch/powerpc/kernel/power7-pmu.c @@ -369,4 +369,4 @@ static int init_power7_pmu(void) return register_power_pmu(&power7_pmu); } -arch_initcall(init_power7_pmu); +early_initcall(init_power7_pmu); diff --git a/arch/powerpc/kernel/ppc970-pmu.c b/arch/powerpc/kernel/ppc970-pmu.c index 3fee685de4d..9a6e093858f 100644 --- a/arch/powerpc/kernel/ppc970-pmu.c +++ b/arch/powerpc/kernel/ppc970-pmu.c @@ -494,4 +494,4 @@ static int init_ppc970_pmu(void) return register_power_pmu(&ppc970_pmu); } -arch_initcall(init_ppc970_pmu); +early_initcall(init_ppc970_pmu); diff --git a/arch/sh/kernel/cpu/sh4/perf_event.c b/arch/sh/kernel/cpu/sh4/perf_event.c index dbf3b4bb71f..748955df018 100644 --- a/arch/sh/kernel/cpu/sh4/perf_event.c +++ b/arch/sh/kernel/cpu/sh4/perf_event.c @@ -250,4 +250,4 @@ static int __init sh7750_pmu_init(void) return register_sh_pmu(&sh7750_pmu); } -arch_initcall(sh7750_pmu_init); +early_initcall(sh7750_pmu_init); diff --git a/arch/sh/kernel/cpu/sh4a/perf_event.c b/arch/sh/kernel/cpu/sh4a/perf_event.c index 58027652573..17e6bebfede 100644 --- a/arch/sh/kernel/cpu/sh4a/perf_event.c +++ b/arch/sh/kernel/cpu/sh4a/perf_event.c @@ -284,4 +284,4 @@ static int __init sh4a_pmu_init(void) return register_sh_pmu(&sh4a_pmu); } -arch_initcall(sh4a_pmu_init); +early_initcall(sh4a_pmu_init); diff --git a/arch/sparc/include/asm/perf_event.h b/arch/sparc/include/asm/perf_event.h index 6e8bfa1786d..4d3dbe3703e 100644 --- a/arch/sparc/include/asm/perf_event.h +++ b/arch/sparc/include/asm/perf_event.h @@ -4,8 +4,6 @@ #ifdef CONFIG_PERF_EVENTS #include -extern void init_hw_perf_events(void); - #define perf_arch_fetch_caller_regs(regs, ip) \ do { \ unsigned long _pstate, _asi, _pil, _i7, _fp; \ @@ -26,8 +24,6 @@ do { \ (regs)->u_regs[UREG_I6] = _fp; \ (regs)->u_regs[UREG_I7] = _i7; \ } while (0) -#else -static inline void init_hw_perf_events(void) { } #endif #endif diff --git a/arch/sparc/kernel/nmi.c b/arch/sparc/kernel/nmi.c index a4bd7ba74c8..300f810142f 100644 --- a/arch/sparc/kernel/nmi.c +++ b/arch/sparc/kernel/nmi.c @@ -270,8 +270,6 @@ int __init nmi_init(void) atomic_set(&nmi_active, -1); } } - if (!err) - init_hw_perf_events(); return err; } diff --git a/arch/sparc/kernel/perf_event.c b/arch/sparc/kernel/perf_event.c index 0d6deb55a2a..75c5b126397 100644 --- a/arch/sparc/kernel/perf_event.c +++ b/arch/sparc/kernel/perf_event.c @@ -1307,20 +1307,23 @@ static bool __init supported_pmu(void) return false; } -void __init init_hw_perf_events(void) +int __init init_hw_perf_events(void) { pr_info("Performance events: "); if (!supported_pmu()) { pr_cont("No support for PMU type '%s'\n", sparc_pmu_type); - return; + return 0; } pr_cont("Supported PMU type is '%s'\n", sparc_pmu_type); perf_pmu_register(&pmu); register_die_notifier(&perf_event_nmi_notifier); + + return 0; } +early_initcall(init_hw_perf_event); void perf_callchain_kernel(struct perf_callchain_entry *entry, struct pt_regs *regs) diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h index 550e26b1dbb..d9d4dae305f 100644 --- a/arch/x86/include/asm/perf_event.h +++ b/arch/x86/include/asm/perf_event.h @@ -125,7 +125,6 @@ union cpuid10_edx { #define IBS_OP_MAX_CNT_EXT 0x007FFFFFULL /* not a register bit mask */ #ifdef CONFIG_PERF_EVENTS -extern void init_hw_perf_events(void); extern void perf_events_lapic_init(void); #define PERF_EVENT_INDEX_OFFSET 0 @@ -156,7 +155,6 @@ extern unsigned long perf_misc_flags(struct pt_regs *regs); } #else -static inline void init_hw_perf_events(void) { } static inline void perf_events_lapic_init(void) { } #endif diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 4b68bda3093..1d59834396b 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -894,7 +894,6 @@ void __init identify_boot_cpu(void) #else vgetcpu_set_mode(); #endif - init_hw_perf_events(); } void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c) diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index c01dfec635d..817d2b195e8 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -1353,7 +1353,7 @@ static void __init pmu_check_apic(void) pr_info("no hardware sampling interrupt available.\n"); } -void __init init_hw_perf_events(void) +int __init init_hw_perf_events(void) { struct event_constraint *c; int err; @@ -1368,11 +1368,11 @@ void __init init_hw_perf_events(void) err = amd_pmu_init(); break; default: - return; + return 0; } if (err != 0) { pr_cont("no PMU driver, software events only.\n"); - return; + return 0; } pmu_check_apic(); @@ -1380,7 +1380,7 @@ void __init init_hw_perf_events(void) /* sanity check that the hardware exists or is emulated */ if (!check_hw_exists()) { pr_cont("Broken PMU hardware detected, software events only.\n"); - return; + return 0; } pr_cont("%s PMU driver.\n", x86_pmu.name); @@ -1431,7 +1431,10 @@ void __init init_hw_perf_events(void) perf_pmu_register(&pmu); perf_cpu_notifier(x86_pmu_notifier); + + return 0; } +early_initcall(init_hw_perf_events); static inline void x86_pmu_read(struct perf_event *event) { diff --git a/include/linux/sched.h b/include/linux/sched.h index 2c79e921a68..d2e63d1e725 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -316,6 +316,7 @@ extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, size_t *lenp, loff_t *ppos); extern unsigned int softlockup_panic; extern int softlockup_thresh; +void lockup_detector_init(void); #else static inline void touch_softlockup_watchdog(void) { @@ -326,6 +327,9 @@ static inline void touch_softlockup_watchdog_sync(void) static inline void touch_all_softlockup_watchdogs(void) { } +static inline void lockup_detector_init(void) +{ +} #endif #ifdef CONFIG_DETECT_HUNG_TASK diff --git a/init/main.c b/init/main.c index 8646401f7a0..261ad7b3fe0 100644 --- a/init/main.c +++ b/init/main.c @@ -882,6 +882,7 @@ static int __init kernel_init(void * unused) smp_prepare_cpus(setup_max_cpus); do_pre_smp_initcalls(); + lockup_detector_init(); smp_init(); sched_init_smp(); diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 6e3c41a4024..cad4e42060a 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -547,13 +547,13 @@ static struct notifier_block __cpuinitdata cpu_nfb = { .notifier_call = cpu_callback }; -static int __init spawn_watchdog_task(void) +void __init lockup_detector_init(void) { void *cpu = (void *)(long)smp_processor_id(); int err; if (no_watchdog) - return 0; + return; err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu); WARN_ON(notifier_to_errno(err)); @@ -561,6 +561,5 @@ static int __init spawn_watchdog_task(void) cpu_callback(&cpu_nfb, CPU_ONLINE, cpu); register_cpu_notifier(&cpu_nfb); - return 0; + return; } -early_initcall(spawn_watchdog_task); -- cgit v1.2.3-70-g09d2 From 5dc3055879b8f659f62abb7c3d1eaa4d02e36d65 Mon Sep 17 00:00:00 2001 From: Don Zickus Date: Mon, 29 Nov 2010 17:07:17 -0500 Subject: x86, NMI: Add back unknown_nmi_panic and nmi_watchdog sysctls Originally adapted from Huang Ying's patch which moved the unknown_nmi_panic to the traps.c file. Because the old nmi watchdog was deleted before this change happened, the unknown_nmi_panic sysctl was lost. This re-adds it. Also, the nmi_watchdog sysctl was re-implemented and its documentation updated accordingly. Patch-inspired-by: Huang Ying Signed-off-by: Don Zickus Reviewed-by: Cyrill Gorcunov Acked-by: Yinghai Lu Cc: fweisbec@gmail.com LKML-Reference: <1291068437-5331-3-git-send-email-dzickus@redhat.com> Signed-off-by: Ingo Molnar --- Documentation/kernel-parameters.txt | 10 +--------- arch/x86/kernel/apic/hw_nmi.c | 3 --- arch/x86/kernel/traps.c | 16 +++++++++++----- kernel/sysctl.c | 16 ++++++++++++++++ kernel/sysctl_binary.c | 1 - kernel/watchdog.c | 2 ++ 6 files changed, 30 insertions(+), 18 deletions(-) (limited to 'kernel/watchdog.c') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index cdd2a6e8a3b..5e55e4623ab 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1579,20 +1579,12 @@ and is between 256 and 4096 characters. It is defined in the file nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels Format: [panic,][num] - Valid num: 0,1,2 + Valid num: 0 0 - turn nmi_watchdog off - 1 - use the IO-APIC timer for the NMI watchdog - 2 - use the local APIC for the NMI watchdog using - a performance counter. Note: This will use one - performance counter and the local APIC's performance - vector. When panic is specified, panic when an NMI watchdog timeout occurs. This is useful when you use a panic=... timeout and need the box quickly up again. - Instead of 1 and 2 it is possible to use the following - symbolic names: lapic and ioapic - Example: nmi_watchdog=2 or nmi_watchdog=panic,lapic netpoll.carrier_timeout= [NET] Specifies amount of time (in seconds) that diff --git a/arch/x86/kernel/apic/hw_nmi.c b/arch/x86/kernel/apic/hw_nmi.c index 2e94eb49359..c558e1101ed 100644 --- a/arch/x86/kernel/apic/hw_nmi.c +++ b/arch/x86/kernel/apic/hw_nmi.c @@ -99,6 +99,3 @@ static int __init register_trigger_all_cpu_backtrace(void) } early_initcall(register_trigger_all_cpu_backtrace); #endif - -/* STUB calls to mimic old nmi_watchdog behaviour */ -int unknown_nmi_panic; diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index f02c179c255..bb6f0416736 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -83,6 +83,8 @@ EXPORT_SYMBOL_GPL(used_vectors); static int ignore_nmis; +int unknown_nmi_panic; + static inline void conditional_sti(struct pt_regs *regs) { if (regs->flags & X86_EFLAGS_IF) @@ -300,6 +302,13 @@ gp_in_kernel: die("general protection fault", regs, error_code); } +static int __init setup_unknown_nmi_panic(char *str) +{ + unknown_nmi_panic = 1; + return 1; +} +__setup("unknown_nmi_panic", setup_unknown_nmi_panic); + static notrace __kprobes void mem_parity_error(unsigned char reason, struct pt_regs *regs) { @@ -371,7 +380,7 @@ unknown_nmi_error(unsigned char reason, struct pt_regs *regs) reason, smp_processor_id()); printk(KERN_EMERG "Do you have a strange power saving mode enabled?\n"); - if (panic_on_unrecovered_nmi) + if (unknown_nmi_panic || panic_on_unrecovered_nmi) panic("NMI: Not continuing"); printk(KERN_EMERG "Dazed and confused, but trying to continue\n"); @@ -397,11 +406,8 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs) if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP) return; - - unknown_nmi_error(reason, regs); -#else - unknown_nmi_error(reason, regs); #endif + unknown_nmi_error(reason, regs); return; } diff --git a/kernel/sysctl.c b/kernel/sysctl.c index cbd97da7a61..46404414d8a 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -745,6 +745,22 @@ static struct ctl_table kern_table[] = { .extra1 = &zero, .extra2 = &one, }, + { + .procname = "nmi_watchdog", + .data = &watchdog_enabled, + .maxlen = sizeof (int), + .mode = 0644, + .proc_handler = proc_dowatchdog_enabled, + }, +#endif +#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) + { + .procname = "unknown_nmi_panic", + .data = &unknown_nmi_panic, + .maxlen = sizeof (int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, #endif #if defined(CONFIG_X86) { diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c index 1357c578606..4b2545a136f 100644 --- a/kernel/sysctl_binary.c +++ b/kernel/sysctl_binary.c @@ -136,7 +136,6 @@ static const struct bin_table bin_kern_table[] = { { CTL_INT, KERN_IA64_UNALIGNED, "ignore-unaligned-usertrap" }, { CTL_INT, KERN_COMPAT_LOG, "compat-log" }, { CTL_INT, KERN_MAX_LOCK_DEPTH, "max_lock_depth" }, - { CTL_INT, KERN_NMI_WATCHDOG, "nmi_watchdog" }, { CTL_INT, KERN_PANIC_ON_NMI, "panic_on_unrecovered_nmi" }, {} }; diff --git a/kernel/watchdog.c b/kernel/watchdog.c index cad4e42060a..eb17e143b5d 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -57,6 +57,8 @@ static int __init hardlockup_panic_setup(char *str) { if (!strncmp(str, "panic", 5)) hardlockup_panic = 1; + else if (!strncmp(str, "0", 1)) + no_watchdog = 1; return 1; } __setup("nmi_watchdog=", hardlockup_panic_setup); -- cgit v1.2.3-70-g09d2 From 909ea96468096b07fbb41aaf69be060d92bd9271 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Wed, 8 Dec 2010 16:22:55 +0100 Subject: core: Replace __get_cpu_var with __this_cpu_read if not used for an address. __get_cpu_var() can be replaced with this_cpu_read and will then use a single read instruction with implied address calculation to access the correct per cpu instance. However, the address of a per cpu variable passed to __this_cpu_read() cannot be determined (since it's an implied address conversion through segment prefixes). Therefore apply this only to uses of __get_cpu_var where the address of the variable is not used. Cc: Pekka Enberg Cc: Hugh Dickins Cc: Thomas Gleixner Acked-by: H. Peter Anvin Signed-off-by: Christoph Lameter Signed-off-by: Tejun Heo --- include/asm-generic/irq_regs.h | 8 ++++---- include/linux/elevator.h | 12 +++--------- include/linux/kernel_stat.h | 2 +- kernel/exit.c | 2 +- kernel/fork.c | 2 +- kernel/hrtimer.c | 2 +- kernel/printk.c | 4 ++-- kernel/rcutree.c | 4 ++-- kernel/softirq.c | 42 +++++++++++++++++++++--------------------- kernel/time/tick-common.c | 2 +- kernel/time/tick-oneshot.c | 4 ++-- kernel/watchdog.c | 36 ++++++++++++++++++------------------ mm/slab.c | 6 +++--- 13 files changed, 60 insertions(+), 66 deletions(-) (limited to 'kernel/watchdog.c') diff --git a/include/asm-generic/irq_regs.h b/include/asm-generic/irq_regs.h index 5ae1d07d4a1..6bf9355fa7e 100644 --- a/include/asm-generic/irq_regs.h +++ b/include/asm-generic/irq_regs.h @@ -22,15 +22,15 @@ DECLARE_PER_CPU(struct pt_regs *, __irq_regs); static inline struct pt_regs *get_irq_regs(void) { - return __get_cpu_var(__irq_regs); + return __this_cpu_read(__irq_regs); } static inline struct pt_regs *set_irq_regs(struct pt_regs *new_regs) { - struct pt_regs *old_regs, **pp_regs = &__get_cpu_var(__irq_regs); + struct pt_regs *old_regs; - old_regs = *pp_regs; - *pp_regs = new_regs; + old_regs = __this_cpu_read(__irq_regs); + __this_cpu_write(__irq_regs, new_regs); return old_regs; } diff --git a/include/linux/elevator.h b/include/linux/elevator.h index 4fd978e7eb8..4d857973d2c 100644 --- a/include/linux/elevator.h +++ b/include/linux/elevator.h @@ -195,15 +195,9 @@ enum { /* * io context count accounting */ -#define elv_ioc_count_mod(name, __val) \ - do { \ - preempt_disable(); \ - __get_cpu_var(name) += (__val); \ - preempt_enable(); \ - } while (0) - -#define elv_ioc_count_inc(name) elv_ioc_count_mod(name, 1) -#define elv_ioc_count_dec(name) elv_ioc_count_mod(name, -1) +#define elv_ioc_count_mod(name, __val) this_cpu_add(name, __val) +#define elv_ioc_count_inc(name) this_cpu_inc(name) +#define elv_ioc_count_dec(name) this_cpu_dec(name) #define elv_ioc_count_read(name) \ ({ \ diff --git a/include/linux/kernel_stat.h b/include/linux/kernel_stat.h index ad54c846911..44e83ba12b5 100644 --- a/include/linux/kernel_stat.h +++ b/include/linux/kernel_stat.h @@ -47,7 +47,7 @@ extern unsigned long long nr_context_switches(void); #ifndef CONFIG_GENERIC_HARDIRQS #define kstat_irqs_this_cpu(irq) \ - (kstat_this_cpu.irqs[irq]) + (this_cpu_read(kstat.irqs[irq]) struct irq_desc; diff --git a/kernel/exit.c b/kernel/exit.c index 676149a4ac5..89c74861a3d 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -69,7 +69,7 @@ static void __unhash_process(struct task_struct *p, bool group_dead) list_del_rcu(&p->tasks); list_del_init(&p->sibling); - __get_cpu_var(process_counts)--; + __this_cpu_dec(process_counts); } list_del_rcu(&p->thread_group); } diff --git a/kernel/fork.c b/kernel/fork.c index 3b159c5991b..e05e27de67d 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1282,7 +1282,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, attach_pid(p, PIDTYPE_SID, task_session(current)); list_add_tail(&p->sibling, &p->real_parent->children); list_add_tail_rcu(&p->tasks, &init_task.tasks); - __get_cpu_var(process_counts)++; + __this_cpu_inc(process_counts); } attach_pid(p, PIDTYPE_PID, pid); nr_threads++; diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 72206cf5c6c..29de5ae4ca9 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -497,7 +497,7 @@ static inline int hrtimer_is_hres_enabled(void) */ static inline int hrtimer_hres_active(void) { - return __get_cpu_var(hrtimer_bases).hres_active; + return __this_cpu_read(hrtimer_bases.hres_active); } /* diff --git a/kernel/printk.c b/kernel/printk.c index 9a2264fc42c..b032317f996 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -1074,8 +1074,8 @@ static DEFINE_PER_CPU(int, printk_pending); void printk_tick(void) { - if (__get_cpu_var(printk_pending)) { - __get_cpu_var(printk_pending) = 0; + if (__this_cpu_read(printk_pending)) { + __this_cpu_write(printk_pending, 0); wake_up_interruptible(&log_wait); } } diff --git a/kernel/rcutree.c b/kernel/rcutree.c index ccdc04c4798..aeebf772d6a 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -367,8 +367,8 @@ void rcu_irq_exit(void) WARN_ON_ONCE(rdtp->dynticks & 0x1); /* If the interrupt queued a callback, get out of dyntick mode. */ - if (__get_cpu_var(rcu_sched_data).nxtlist || - __get_cpu_var(rcu_bh_data).nxtlist) + if (__this_cpu_read(rcu_sched_data.nxtlist) || + __this_cpu_read(rcu_bh_data.nxtlist)) set_need_resched(); } diff --git a/kernel/softirq.c b/kernel/softirq.c index 18f4be0d5fe..d0a0dda52c1 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -70,7 +70,7 @@ char *softirq_to_name[NR_SOFTIRQS] = { static void wakeup_softirqd(void) { /* Interrupts are disabled: no need to stop preemption */ - struct task_struct *tsk = __get_cpu_var(ksoftirqd); + struct task_struct *tsk = __this_cpu_read(ksoftirqd); if (tsk && tsk->state != TASK_RUNNING) wake_up_process(tsk); @@ -388,8 +388,8 @@ void __tasklet_schedule(struct tasklet_struct *t) local_irq_save(flags); t->next = NULL; - *__get_cpu_var(tasklet_vec).tail = t; - __get_cpu_var(tasklet_vec).tail = &(t->next); + *__this_cpu_read(tasklet_vec.tail) = t; + __this_cpu_write(tasklet_vec.tail, &(t->next)); raise_softirq_irqoff(TASKLET_SOFTIRQ); local_irq_restore(flags); } @@ -402,8 +402,8 @@ void __tasklet_hi_schedule(struct tasklet_struct *t) local_irq_save(flags); t->next = NULL; - *__get_cpu_var(tasklet_hi_vec).tail = t; - __get_cpu_var(tasklet_hi_vec).tail = &(t->next); + *__this_cpu_read(tasklet_hi_vec.tail) = t; + __this_cpu_write(tasklet_hi_vec.tail, &(t->next)); raise_softirq_irqoff(HI_SOFTIRQ); local_irq_restore(flags); } @@ -414,8 +414,8 @@ void __tasklet_hi_schedule_first(struct tasklet_struct *t) { BUG_ON(!irqs_disabled()); - t->next = __get_cpu_var(tasklet_hi_vec).head; - __get_cpu_var(tasklet_hi_vec).head = t; + t->next = __this_cpu_read(tasklet_hi_vec.head); + __this_cpu_write(tasklet_hi_vec.head, t); __raise_softirq_irqoff(HI_SOFTIRQ); } @@ -426,9 +426,9 @@ static void tasklet_action(struct softirq_action *a) struct tasklet_struct *list; local_irq_disable(); - list = __get_cpu_var(tasklet_vec).head; - __get_cpu_var(tasklet_vec).head = NULL; - __get_cpu_var(tasklet_vec).tail = &__get_cpu_var(tasklet_vec).head; + list = __this_cpu_read(tasklet_vec.head); + __this_cpu_write(tasklet_vec.head, NULL); + __this_cpu_write(tasklet_vec.tail, &__get_cpu_var(tasklet_vec).head); local_irq_enable(); while (list) { @@ -449,8 +449,8 @@ static void tasklet_action(struct softirq_action *a) local_irq_disable(); t->next = NULL; - *__get_cpu_var(tasklet_vec).tail = t; - __get_cpu_var(tasklet_vec).tail = &(t->next); + *__this_cpu_read(tasklet_vec.tail) = t; + __this_cpu_write(tasklet_vec.tail, &(t->next)); __raise_softirq_irqoff(TASKLET_SOFTIRQ); local_irq_enable(); } @@ -461,9 +461,9 @@ static void tasklet_hi_action(struct softirq_action *a) struct tasklet_struct *list; local_irq_disable(); - list = __get_cpu_var(tasklet_hi_vec).head; - __get_cpu_var(tasklet_hi_vec).head = NULL; - __get_cpu_var(tasklet_hi_vec).tail = &__get_cpu_var(tasklet_hi_vec).head; + list = __this_cpu_read(tasklet_hi_vec.head); + __this_cpu_write(tasklet_hi_vec.head, NULL); + __this_cpu_write(tasklet_hi_vec.tail, &__get_cpu_var(tasklet_hi_vec).head); local_irq_enable(); while (list) { @@ -484,8 +484,8 @@ static void tasklet_hi_action(struct softirq_action *a) local_irq_disable(); t->next = NULL; - *__get_cpu_var(tasklet_hi_vec).tail = t; - __get_cpu_var(tasklet_hi_vec).tail = &(t->next); + *__this_cpu_read(tasklet_hi_vec.tail) = t; + __this_cpu_write(tasklet_hi_vec.tail, &(t->next)); __raise_softirq_irqoff(HI_SOFTIRQ); local_irq_enable(); } @@ -802,16 +802,16 @@ static void takeover_tasklets(unsigned int cpu) /* Find end, append list for that CPU. */ if (&per_cpu(tasklet_vec, cpu).head != per_cpu(tasklet_vec, cpu).tail) { - *(__get_cpu_var(tasklet_vec).tail) = per_cpu(tasklet_vec, cpu).head; - __get_cpu_var(tasklet_vec).tail = per_cpu(tasklet_vec, cpu).tail; + *__this_cpu_read(tasklet_vec.tail) = per_cpu(tasklet_vec, cpu).head; + this_cpu_write(tasklet_vec.tail, per_cpu(tasklet_vec, cpu).tail); per_cpu(tasklet_vec, cpu).head = NULL; per_cpu(tasklet_vec, cpu).tail = &per_cpu(tasklet_vec, cpu).head; } raise_softirq_irqoff(TASKLET_SOFTIRQ); if (&per_cpu(tasklet_hi_vec, cpu).head != per_cpu(tasklet_hi_vec, cpu).tail) { - *__get_cpu_var(tasklet_hi_vec).tail = per_cpu(tasklet_hi_vec, cpu).head; - __get_cpu_var(tasklet_hi_vec).tail = per_cpu(tasklet_hi_vec, cpu).tail; + *__this_cpu_read(tasklet_hi_vec.tail) = per_cpu(tasklet_hi_vec, cpu).head; + __this_cpu_write(tasklet_hi_vec.tail, per_cpu(tasklet_hi_vec, cpu).tail); per_cpu(tasklet_hi_vec, cpu).head = NULL; per_cpu(tasklet_hi_vec, cpu).tail = &per_cpu(tasklet_hi_vec, cpu).head; } diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index b6b898d2eee..051bc80a0c4 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -49,7 +49,7 @@ struct tick_device *tick_get_device(int cpu) */ int tick_is_oneshot_available(void) { - struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev; + struct clock_event_device *dev = __this_cpu_read(tick_cpu_device.evtdev); return dev && (dev->features & CLOCK_EVT_FEAT_ONESHOT); } diff --git a/kernel/time/tick-oneshot.c b/kernel/time/tick-oneshot.c index aada0e52680..5cbc101f908 100644 --- a/kernel/time/tick-oneshot.c +++ b/kernel/time/tick-oneshot.c @@ -95,7 +95,7 @@ int tick_dev_program_event(struct clock_event_device *dev, ktime_t expires, */ int tick_program_event(ktime_t expires, int force) { - struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev; + struct clock_event_device *dev = __this_cpu_read(tick_cpu_device.evtdev); return tick_dev_program_event(dev, expires, force); } @@ -167,7 +167,7 @@ int tick_oneshot_mode_active(void) int ret; local_irq_save(flags); - ret = __get_cpu_var(tick_cpu_device).mode == TICKDEV_MODE_ONESHOT; + ret = __this_cpu_read(tick_cpu_device.mode) == TICKDEV_MODE_ONESHOT; local_irq_restore(flags); return ret; diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 6e3c41a4024..8037a86106e 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -116,12 +116,12 @@ static void __touch_watchdog(void) { int this_cpu = smp_processor_id(); - __get_cpu_var(watchdog_touch_ts) = get_timestamp(this_cpu); + __this_cpu_write(watchdog_touch_ts, get_timestamp(this_cpu)); } void touch_softlockup_watchdog(void) { - __raw_get_cpu_var(watchdog_touch_ts) = 0; + __this_cpu_write(watchdog_touch_ts, 0); } EXPORT_SYMBOL(touch_softlockup_watchdog); @@ -165,12 +165,12 @@ void touch_softlockup_watchdog_sync(void) /* watchdog detector functions */ static int is_hardlockup(void) { - unsigned long hrint = __get_cpu_var(hrtimer_interrupts); + unsigned long hrint = __this_cpu_read(hrtimer_interrupts); - if (__get_cpu_var(hrtimer_interrupts_saved) == hrint) + if (__this_cpu_read(hrtimer_interrupts_saved) == hrint) return 1; - __get_cpu_var(hrtimer_interrupts_saved) = hrint; + __this_cpu_write(hrtimer_interrupts_saved, hrint); return 0; } #endif @@ -203,8 +203,8 @@ static void watchdog_overflow_callback(struct perf_event *event, int nmi, /* Ensure the watchdog never gets throttled */ event->hw.interrupts = 0; - if (__get_cpu_var(watchdog_nmi_touch) == true) { - __get_cpu_var(watchdog_nmi_touch) = false; + if (__this_cpu_read(watchdog_nmi_touch) == true) { + __this_cpu_write(watchdog_nmi_touch, false); return; } @@ -218,7 +218,7 @@ static void watchdog_overflow_callback(struct perf_event *event, int nmi, int this_cpu = smp_processor_id(); /* only print hardlockups once */ - if (__get_cpu_var(hard_watchdog_warn) == true) + if (__this_cpu_read(hard_watchdog_warn) == true) return; if (hardlockup_panic) @@ -226,16 +226,16 @@ static void watchdog_overflow_callback(struct perf_event *event, int nmi, else WARN(1, "Watchdog detected hard LOCKUP on cpu %d", this_cpu); - __get_cpu_var(hard_watchdog_warn) = true; + __this_cpu_write(hard_watchdog_warn, true); return; } - __get_cpu_var(hard_watchdog_warn) = false; + __this_cpu_write(hard_watchdog_warn, false); return; } static void watchdog_interrupt_count(void) { - __get_cpu_var(hrtimer_interrupts)++; + __this_cpu_inc(hrtimer_interrupts); } #else static inline void watchdog_interrupt_count(void) { return; } @@ -244,7 +244,7 @@ static inline void watchdog_interrupt_count(void) { return; } /* watchdog kicker functions */ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) { - unsigned long touch_ts = __get_cpu_var(watchdog_touch_ts); + unsigned long touch_ts = __this_cpu_read(watchdog_touch_ts); struct pt_regs *regs = get_irq_regs(); int duration; @@ -252,18 +252,18 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) watchdog_interrupt_count(); /* kick the softlockup detector */ - wake_up_process(__get_cpu_var(softlockup_watchdog)); + wake_up_process(__this_cpu_read(softlockup_watchdog)); /* .. and repeat */ hrtimer_forward_now(hrtimer, ns_to_ktime(get_sample_period())); if (touch_ts == 0) { - if (unlikely(__get_cpu_var(softlockup_touch_sync))) { + if (unlikely(__this_cpu_read(softlockup_touch_sync))) { /* * If the time stamp was touched atomically * make sure the scheduler tick is up to date. */ - __get_cpu_var(softlockup_touch_sync) = false; + __this_cpu_write(softlockup_touch_sync, false); sched_clock_tick(); } __touch_watchdog(); @@ -279,7 +279,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) duration = is_softlockup(touch_ts); if (unlikely(duration)) { /* only warn once */ - if (__get_cpu_var(soft_watchdog_warn) == true) + if (__this_cpu_read(soft_watchdog_warn) == true) return HRTIMER_RESTART; printk(KERN_ERR "BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n", @@ -294,9 +294,9 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) if (softlockup_panic) panic("softlockup: hung tasks"); - __get_cpu_var(soft_watchdog_warn) = true; + __this_cpu_write(soft_watchdog_warn, true); } else - __get_cpu_var(soft_watchdog_warn) = false; + __this_cpu_write(soft_watchdog_warn, false); return HRTIMER_RESTART; } diff --git a/mm/slab.c b/mm/slab.c index b1e40dafbab..316d75596f3 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -829,12 +829,12 @@ static void init_reap_node(int cpu) static void next_reap_node(void) { - int node = __get_cpu_var(slab_reap_node); + int node = __this_cpu_read(slab_reap_node); node = next_node(node, node_online_map); if (unlikely(node >= MAX_NUMNODES)) node = first_node(node_online_map); - __get_cpu_var(slab_reap_node) = node; + __this_cpu_write(slab_reap_node, node); } #else @@ -1012,7 +1012,7 @@ static void __drain_alien_cache(struct kmem_cache *cachep, */ static void reap_alien(struct kmem_cache *cachep, struct kmem_list3 *l3) { - int node = __get_cpu_var(slab_reap_node); + int node = __this_cpu_read(slab_reap_node); if (l3->alien) { struct array_cache *ac = l3->alien[node]; -- cgit v1.2.3-70-g09d2 From 551423748a4eba55f2eb0fc250d757986471f187 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Sun, 2 Jan 2011 23:02:42 +0000 Subject: watchdog: Improve initialisation error message and documentation The error message 'NMI watchdog failed to create perf event...' does not make it clear that this is a fatal error for the watchdog. It also currently prints the error value as a pointer, rather than extracting the error code with PTR_ERR(). Fix that. Add a note to the description of the 'nowatchdog' kernel parameter to associate it with this message. Reported-by: Cesare Leonardi Signed-off-by: Ben Hutchings Cc: 599368@bugs.debian.org Cc: 608138@bugs.debian.org Cc: Don Zickus Cc: Frederic Weisbecker Cc: # .37.x and later LKML-Reference: <1294009362.3167.126.camel@localhost> Signed-off-by: Ingo Molnar --- Documentation/kernel-parameters.txt | 2 +- kernel/watchdog.c | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-) (limited to 'kernel/watchdog.c') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 8b61c936099..01ece1b9213 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1759,7 +1759,7 @@ and is between 256 and 4096 characters. It is defined in the file nousb [USB] Disable the USB subsystem - nowatchdog [KNL] Disable the lockup detector. + nowatchdog [KNL] Disable the lockup detector (NMI watchdog). nowb [ARM] diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 6e3c41a4024..5b082156cd2 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -364,7 +364,8 @@ static int watchdog_nmi_enable(int cpu) goto out_save; } - printk(KERN_ERR "NMI watchdog failed to create perf event on cpu%i: %p\n", cpu, event); + printk(KERN_ERR "NMI watchdog disabled for cpu%i: unable to create perf event: %ld\n", + cpu, PTR_ERR(event)); return PTR_ERR(event); /* success path */ -- cgit v1.2.3-70-g09d2