Commit bce8fc4c authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'perf-fixes-for-linus' of... 

Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf tools: Remove -Wcast-align
  perf tools: Fix compatibility with libelf 0.8 and autodetect
  perf events: Don't generate events for the idle task when exclude_idle is set
  perf events: Fix swevent hrtimer sampling by keeping track of remaining time when enabling/disabling swevent hrtimers
parents a5e3013d ec29b8d2

include/linux/perf_event.h

+2 −2
Original line number Diff line number Diff line
@@ -471,8 +471,8 @@ struct hw_perf_event { 
			unsigned long	event_base;

			int		idx;

		};

		union { /* software */

			atomic64_t	count;

		struct { /* software */

			s64		remaining;

			struct hrtimer	hrtimer;

		};

	};

kernel/perf_event.c

+44 −22
Original line number Diff line number Diff line
@@ -3959,6 +3959,7 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) 
		regs = task_pt_regs(current);



	if (regs) {

		if (!(event->attr.exclude_idle && current->pid == 0))

			if (perf_event_overflow(event, 0, &data, regs))

				ret = HRTIMER_NORESTART;

	}
@@ -3969,6 +3970,42 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) 
	return ret;

}



static void perf_swevent_start_hrtimer(struct perf_event *event)

{

	struct hw_perf_event *hwc = &event->hw;



	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);

	hwc->hrtimer.function = perf_swevent_hrtimer;

	if (hwc->sample_period) {

		u64 period;



		if (hwc->remaining) {

			if (hwc->remaining < 0)

				period = 10000;

			else

				period = hwc->remaining;

			hwc->remaining = 0;

		} else {

			period = max_t(u64, 10000, hwc->sample_period);

		}

		__hrtimer_start_range_ns(&hwc->hrtimer,

				ns_to_ktime(period), 0,

				HRTIMER_MODE_REL, 0);

	}

}



static void perf_swevent_cancel_hrtimer(struct perf_event *event)

{

	struct hw_perf_event *hwc = &event->hw;



	if (hwc->sample_period) {

		ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer);

		hwc->remaining = ktime_to_ns(remaining);



		hrtimer_cancel(&hwc->hrtimer);

	}

}



/*

 * Software event: cpu wall time clock

 */
@@ -3991,22 +4028,14 @@ static int cpu_clock_perf_event_enable(struct perf_event *event) 
	int cpu = raw_smp_processor_id();



	atomic64_set(&hwc->prev_count, cpu_clock(cpu));

	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);

	hwc->hrtimer.function = perf_swevent_hrtimer;

	if (hwc->sample_period) {

		u64 period = max_t(u64, 10000, hwc->sample_period);

		__hrtimer_start_range_ns(&hwc->hrtimer,

				ns_to_ktime(period), 0,

				HRTIMER_MODE_REL, 0);

	}

	perf_swevent_start_hrtimer(event);



	return 0;

}



static void cpu_clock_perf_event_disable(struct perf_event *event)

{

	if (event->hw.sample_period)

		hrtimer_cancel(&event->hw.hrtimer);

	perf_swevent_cancel_hrtimer(event);

	cpu_clock_perf_event_update(event);

}
@@ -4043,22 +4072,15 @@ static int task_clock_perf_event_enable(struct perf_event *event) 
	now = event->ctx->time;



	atomic64_set(&hwc->prev_count, now);

	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);

	hwc->hrtimer.function = perf_swevent_hrtimer;

	if (hwc->sample_period) {

		u64 period = max_t(u64, 10000, hwc->sample_period);

		__hrtimer_start_range_ns(&hwc->hrtimer,

				ns_to_ktime(period), 0,

				HRTIMER_MODE_REL, 0);

	}



	perf_swevent_start_hrtimer(event);



	return 0;

}



static void task_clock_perf_event_disable(struct perf_event *event)

{

	if (event->hw.sample_period)

		hrtimer_cancel(&event->hw.hrtimer);

	perf_swevent_cancel_hrtimer(event);

	task_clock_perf_event_update(event, event->ctx->time);



}

tools/perf/Makefile

+6 −3
Original line number Diff line number Diff line
@@ -177,8 +177,7 @@ endif 
# Include saner warnings here, which can catch bugs:

#



EXTRA_WARNINGS := -Wcast-align

EXTRA_WARNINGS := $(EXTRA_WARNINGS) -Wformat

EXTRA_WARNINGS := -Wformat

EXTRA_WARNINGS := $(EXTRA_WARNINGS) -Wformat-security

EXTRA_WARNINGS := $(EXTRA_WARNINGS) -Wformat-y2k

EXTRA_WARNINGS := $(EXTRA_WARNINGS) -Wshadow
@@ -422,7 +421,11 @@ ifeq ($(uname_S),Darwin) 
	PTHREAD_LIBS =

endif



ifeq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf * elf = elf_begin(0, ELF_C_READ, 0); return (long)elf; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -o /dev/null $(ALL_LDFLAGS) > /dev/null 2>&1 && echo y"), y)

	ifneq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf * elf = elf_begin(0, ELF_C_READ_MMAP, 0); return (long)elf; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -o /dev/null $(ALL_LDFLAGS) > /dev/null 2>&1 && echo y"), y)

		BASIC_CFLAGS += -DLIBELF_NO_MMAP

	endif

else

	msg := $(error No libelf.h/libelf found, please install libelf-dev/elfutils-libelf-devel and glibc-dev[el]);

endif

tools/perf/util/symbol.c

+3 −3
Original line number Diff line number Diff line
@@ -413,7 +413,7 @@ static int dso__synthesize_plt_symbols(struct dso *self, int v) 
	if (fd < 0)

		goto out;



	elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);

	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);

	if (elf == NULL)

		goto out_close;
@@ -533,7 +533,7 @@ static int dso__load_sym(struct dso *self, int fd, const char *name, 
	Elf *elf;

	int nr = 0, kernel = !strcmp("[kernel]", self->name);



	elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);

	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);

	if (elf == NULL) {

		if (v)

			fprintf(stderr, "%s: cannot read %s ELF file.\n",
@@ -675,7 +675,7 @@ static char *dso__read_build_id(struct dso *self, int v) 
	if (fd < 0)

		goto out;



	elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);

	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);

	if (elf == NULL) {

		if (v)

			fprintf(stderr, "%s: cannot read %s ELF file.\n",

tools/perf/util/symbol.h

+10 −0
Original line number Diff line number Diff line
@@ -27,6 +27,16 @@ static inline char *bfd_demangle(void __used *v, const char __used *c, 
#endif

#endif



/*

 * libelf 0.8.x and earlier do not support ELF_C_READ_MMAP;

 * for newer versions we can use mmap to reduce memory usage:

 */

#ifdef LIBELF_NO_MMAP

# define PERF_ELF_C_READ_MMAP ELF_C_READ

#else

# define PERF_ELF_C_READ_MMAP ELF_C_READ_MMAP

#endif



#ifndef DMGL_PARAMS

#define DMGL_PARAMS      (1 << 0)       /* Include function args */

#define DMGL_ANSI        (1 << 1)       /* Include const, volatile, etc */

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