From bd2f55361f18347e890d52ff9cfd8895455ec11b Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 21 Mar 2011 12:33:18 +0100 Subject: sched/rt: Use schedule_preempt_disabled() Coccinelle based conversion. Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra Link: http://lkml.kernel.org/n/tip-24swm5zut3h9c4a6s46x8rws@git.kernel.org Signed-off-by: Ingo Molnar --- arch/arm/kernel/process.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 971d65c253a9..c2ae3cd331fe 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -239,9 +239,7 @@ void cpu_idle(void) leds_event(led_idle_end); rcu_idle_exit(); tick_nohz_idle_exit(); - preempt_enable_no_resched(); - schedule(); - preempt_disable(); + schedule_preempt_disabled(); } } -- cgit v1.3-14-g43fede From 2481c5fa6db0237e4f0168f88913178b2b495b7c Mon Sep 17 00:00:00 2001 From: Stephane Eranian Date: Thu, 9 Feb 2012 23:20:59 +0100 Subject: perf: Disable PERF_SAMPLE_BRANCH_* when not supported PERF_SAMPLE_BRANCH_* is disabled for: - SW events (sw counters, tracepoints) - HW breakpoints - ALL but Intel x86 architecture - AMD64 processors Signed-off-by: Stephane Eranian Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1328826068-11713-10-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar --- arch/alpha/kernel/perf_event.c | 4 ++++ arch/arm/kernel/perf_event.c | 4 ++++ arch/mips/kernel/perf_event_mipsxx.c | 4 ++++ arch/powerpc/kernel/perf_event.c | 4 ++++ arch/sh/kernel/perf_event.c | 4 ++++ arch/sparc/kernel/perf_event.c | 4 ++++ arch/x86/kernel/cpu/perf_event_amd.c | 3 +++ kernel/events/core.c | 24 ++++++++++++++++++++++++ kernel/events/hw_breakpoint.c | 6 ++++++ 9 files changed, 57 insertions(+) (limited to 'arch/arm/kernel') diff --git a/arch/alpha/kernel/perf_event.c b/arch/alpha/kernel/perf_event.c index 8143cd7cdbfb..0dae252f7a33 100644 --- a/arch/alpha/kernel/perf_event.c +++ b/arch/alpha/kernel/perf_event.c @@ -685,6 +685,10 @@ static int alpha_pmu_event_init(struct perf_event *event) { int err; + /* does not support taken branch sampling */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + switch (event->attr.type) { case PERF_TYPE_RAW: case PERF_TYPE_HARDWARE: diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 5bb91bf3d47f..a23c42abc694 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -539,6 +539,10 @@ static int armpmu_event_init(struct perf_event *event) int err = 0; atomic_t *active_events = &armpmu->active_events; + /* does not support taken branch sampling */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + if (armpmu->map_event(event) == -ENOENT) return -ENOENT; diff --git a/arch/mips/kernel/perf_event_mipsxx.c b/arch/mips/kernel/perf_event_mipsxx.c index e3b897acfbc0..811084f4e422 100644 --- a/arch/mips/kernel/perf_event_mipsxx.c +++ b/arch/mips/kernel/perf_event_mipsxx.c @@ -606,6 +606,10 @@ static int mipspmu_event_init(struct perf_event *event) { int err = 0; + /* does not support taken branch sampling */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + switch (event->attr.type) { case PERF_TYPE_RAW: case PERF_TYPE_HARDWARE: diff --git a/arch/powerpc/kernel/perf_event.c b/arch/powerpc/kernel/perf_event.c index f04c2301725e..c2e27ede07ec 100644 --- a/arch/powerpc/kernel/perf_event.c +++ b/arch/powerpc/kernel/perf_event.c @@ -1084,6 +1084,10 @@ static int power_pmu_event_init(struct perf_event *event) if (!ppmu) return -ENOENT; + /* does not support taken branch sampling */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + switch (event->attr.type) { case PERF_TYPE_HARDWARE: ev = event->attr.config; diff --git a/arch/sh/kernel/perf_event.c b/arch/sh/kernel/perf_event.c index 10b14e3a7eb8..068b8a2759b5 100644 --- a/arch/sh/kernel/perf_event.c +++ b/arch/sh/kernel/perf_event.c @@ -310,6 +310,10 @@ static int sh_pmu_event_init(struct perf_event *event) { int err; + /* does not support taken branch sampling */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + switch (event->attr.type) { case PERF_TYPE_RAW: case PERF_TYPE_HW_CACHE: diff --git a/arch/sparc/kernel/perf_event.c b/arch/sparc/kernel/perf_event.c index 614da624330c..8e16a4a21582 100644 --- a/arch/sparc/kernel/perf_event.c +++ b/arch/sparc/kernel/perf_event.c @@ -1105,6 +1105,10 @@ static int sparc_pmu_event_init(struct perf_event *event) if (atomic_read(&nmi_active) < 0) return -ENODEV; + /* does not support taken branch sampling */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + switch (attr->type) { case PERF_TYPE_HARDWARE: if (attr->config >= sparc_pmu->max_events) diff --git a/arch/x86/kernel/cpu/perf_event_amd.c b/arch/x86/kernel/cpu/perf_event_amd.c index 67250a52430b..dd002faff7a6 100644 --- a/arch/x86/kernel/cpu/perf_event_amd.c +++ b/arch/x86/kernel/cpu/perf_event_amd.c @@ -139,6 +139,9 @@ static int amd_pmu_hw_config(struct perf_event *event) if (ret) return ret; + if (has_branch_stack(event)) + return -EOPNOTSUPP; + if (event->attr.exclude_host && event->attr.exclude_guest) /* * When HO == GO == 1 the hardware treats that as GO == HO == 0 diff --git a/kernel/events/core.c b/kernel/events/core.c index 5820efdf47cd..242bb51c67f2 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -5044,6 +5044,12 @@ static int perf_swevent_init(struct perf_event *event) if (event->attr.type != PERF_TYPE_SOFTWARE) return -ENOENT; + /* + * no branch sampling for software events + */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + switch (event_id) { case PERF_COUNT_SW_CPU_CLOCK: case PERF_COUNT_SW_TASK_CLOCK: @@ -5154,6 +5160,12 @@ static int perf_tp_event_init(struct perf_event *event) if (event->attr.type != PERF_TYPE_TRACEPOINT) return -ENOENT; + /* + * no branch sampling for tracepoint events + */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + err = perf_trace_init(event); if (err) return err; @@ -5379,6 +5391,12 @@ static int cpu_clock_event_init(struct perf_event *event) if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) return -ENOENT; + /* + * no branch sampling for software events + */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + perf_swevent_init_hrtimer(event); return 0; @@ -5453,6 +5471,12 @@ static int task_clock_event_init(struct perf_event *event) if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) return -ENOENT; + /* + * no branch sampling for software events + */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + perf_swevent_init_hrtimer(event); return 0; diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c index 3330022a7ac1..bb38c4d3ee12 100644 --- a/kernel/events/hw_breakpoint.c +++ b/kernel/events/hw_breakpoint.c @@ -581,6 +581,12 @@ static int hw_breakpoint_event_init(struct perf_event *bp) if (bp->attr.type != PERF_TYPE_BREAKPOINT) return -ENOENT; + /* + * no branch sampling for breakpoint events + */ + if (has_branch_stack(bp)) + return -EOPNOTSUPP; + err = register_perf_hw_breakpoint(bp); if (err) return err; -- cgit v1.3-14-g43fede From 5fbd036b552f633abb394a319f7c62a5c86a9cd7 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 15 Dec 2011 17:09:22 +0100 Subject: sched: Cleanup cpu_active madness Stepan found: CPU0 CPUn _cpu_up() __cpu_up() boostrap() notify_cpu_starting() set_cpu_online() while (!cpu_active()) cpu_relax() smp_call_function(.wait=1) /* we find cpu_online() is true */ arch_send_call_function_ipi_mask() /* wait-forever-more */ local_irq_enable() cpu_notify(CPU_ONLINE) sched_cpu_active() set_cpu_active() Now the purpose of cpu_active is mostly with bringing down a cpu, where we mark it !active to avoid the load-balancer from moving tasks to it while we tear down the cpu. This is required because we only update the sched_domain tree after we brought the cpu-down. And this is needed so that some tasks can still run while we bring it down, we just don't want new tasks to appear. On cpu-up however the sched_domain tree doesn't yet include the new cpu, so its invisible to the load-balancer, regardless of the active state. So instead of setting the active state after we boot the new cpu (and consequently having to wait for it before enabling interrupts) set the cpu active before we set it online and avoid the whole mess. Reported-by: Stepan Moskovchenko Signed-off-by: Peter Zijlstra Acked-by: Thomas Gleixner Link: http://lkml.kernel.org/r/1323965362.18942.71.camel@twins Signed-off-by: Ingo Molnar --- arch/arm/kernel/smp.c | 7 ------- arch/hexagon/kernel/smp.c | 2 -- arch/s390/kernel/smp.c | 6 ------ arch/x86/kernel/smpboot.c | 13 ------------- kernel/sched/core.c | 2 +- 5 files changed, 1 insertion(+), 29 deletions(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index cdeb727527d3..d616ed51e7a7 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -295,13 +295,6 @@ asmlinkage void __cpuinit secondary_start_kernel(void) */ percpu_timer_setup(); - while (!cpu_active(cpu)) - cpu_relax(); - - /* - * cpu_active bit is set, so it's safe to enalbe interrupts - * now. - */ local_irq_enable(); local_fiq_enable(); diff --git a/arch/hexagon/kernel/smp.c b/arch/hexagon/kernel/smp.c index c871a2cffaef..0123c63e9a3a 100644 --- a/arch/hexagon/kernel/smp.c +++ b/arch/hexagon/kernel/smp.c @@ -179,8 +179,6 @@ void __cpuinit start_secondary(void) printk(KERN_INFO "%s cpu %d\n", __func__, current_thread_info()->cpu); set_cpu_online(cpu, true); - while (!cpumask_test_cpu(cpu, cpu_active_mask)) - cpu_relax(); local_irq_enable(); cpu_idle(); diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 2398ce6b15ae..b0e28c47ab83 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -550,12 +550,6 @@ int __cpuinit start_secondary(void *cpuvoid) S390_lowcore.restart_psw.addr = PSW_ADDR_AMODE | (unsigned long) psw_restart_int_handler; __ctl_set_bit(0, 28); /* Enable lowcore protection */ - /* - * Wait until the cpu which brought this one up marked it - * active before enabling interrupts. - */ - while (!cpumask_test_cpu(smp_processor_id(), cpu_active_mask)) - cpu_relax(); local_irq_enable(); /* cpu_idle will call schedule for us */ cpu_idle(); diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 66d250c00d11..58f78165d308 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -291,19 +291,6 @@ notrace static void __cpuinit start_secondary(void *unused) per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE; x86_platform.nmi_init(); - /* - * Wait until the cpu which brought this one up marked it - * online before enabling interrupts. If we don't do that then - * we can end up waking up the softirq thread before this cpu - * reached the active state, which makes the scheduler unhappy - * and schedule the softirq thread on the wrong cpu. This is - * only observable with forced threaded interrupts, but in - * theory it could also happen w/o them. It's just way harder - * to achieve. - */ - while (!cpumask_test_cpu(smp_processor_id(), cpu_active_mask)) - cpu_relax(); - /* enable local interrupts */ local_irq_enable(); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 95545126be1c..b1ccce819ce2 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5410,7 +5410,7 @@ static int __cpuinit sched_cpu_active(struct notifier_block *nfb, unsigned long action, void *hcpu) { switch (action & ~CPU_TASKS_FROZEN) { - case CPU_ONLINE: + case CPU_STARTING: case CPU_DOWN_FAILED: set_cpu_active((long)hcpu, true); return NOTIFY_OK; -- cgit v1.3-14-g43fede