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#ifndef CPUS_H
#define CPUS_H

#include <unistd.h>
#include "built_in.h"
#include "die.h"

static inline unsigned int get_number_cpus(void)
{
	int ret = sysconf(_SC_NPROCESSORS_CONF);

	if (unlikely(ret <= 0))
		panic("get_number_cpus error!\n");

	return ret;
}

static inline unsigned int get_number_cpus_online(void)
{
	int ret = sysconf(_SC_NPROCESSORS_ONLN);

	if (unlikely(ret <= 0))
		panic("get_number_cpus_online error!\n");

	return ret;
}

#endif /* CPUS_H */
tion value='2'>stat only
authorJiri Olsa <jolsa@kernel.org>2016-12-28 14:31:03 +0100
committerIngo Molnar <mingo@kernel.org>2017-01-14 11:06:49 +0100
commit475113d937adfd150eb82b5e2c5507125a68e7af (patch)
tree8c5b0c58d3308738b440e5e1ec8e479ecf6ac11e /sound/soc/nuc900
parent321027c1fe77f892f4ea07846aeae08cefbbb290 (diff)
perf/x86/intel: Account interrupts for PEBS errors
It's possible to set up PEBS events to get only errors and not any data, like on SNB-X (model 45) and IVB-EP (model 62) via 2 perf commands running simultaneously: taskset -c 1 ./perf record -c 4 -e branches:pp -j any -C 10 This leads to a soft lock up, because the error path of the intel_pmu_drain_pebs_nhm() does not account event->hw.interrupt for error PEBS interrupts, so in case you're getting ONLY errors you don't have a way to stop the event when it's over the max_samples_per_tick limit: NMI watchdog: BUG: soft lockup - CPU#22 stuck for 22s! [perf_fuzzer:5816] ... RIP: 0010:[<ffffffff81159232>] [<ffffffff81159232>] smp_call_function_single+0xe2/0x140 ... Call Trace: ? trace_hardirqs_on_caller+0xf5/0x1b0 ? perf_cgroup_attach+0x70/0x70 perf_install_in_context+0x199/0x1b0 ? ctx_resched+0x90/0x90 SYSC_perf_event_open+0x641/0xf90 SyS_perf_event_open+0x9/0x10 do_syscall_64+0x6c/0x1f0 entry_SYSCALL64_slow_path+0x25/0x25 Add perf_event_account_interrupt() which does the interrupt and frequency checks and call it from intel_pmu_drain_pebs_nhm()'s error path. We keep the pending_kill and pending_wakeup logic only in the __perf_event_overflow() path, because they make sense only if there's any data to deliver. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vince@deater.net> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1482931866-6018-2-git-send-email-jolsa@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'sound/soc/nuc900')