Commit 17d7a112 authored by Hitoshi Mitake's avatar Hitoshi Mitake Committed by Arnaldo Carvalho de Melo
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perf bench: Fix confused variable namings and descriptions in mem subsystem 



As Namhyung Kim pointed, there are confused namings and descriptions of words
"cycle" and "clock" in mem-memset.c and mem-memcpy.c.

With the option "-c" (or "--clock", now renamed as "--cycle"), mem subsystem
measures cost of memset() and memcpy() with cpu-cycles event.

But current mem subsystem source code contains lots of confused variable
namings and descriptions with "clock" (e.g. the variable use_clock). This is a
very bad style because there is another software event named "cpu-clock". This
patch replaces wrong usage of "clock" to "cycle".

v2: modified Documentation/perf-bench.txt for the descriptions of
--cycle option

Signed-off-by: default avatarHitoshi Mitake <h.mitake@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1341236777-18457-1-git-send-email-h.mitake@gmail.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 339ce005

tools/perf/Documentation/perf-bench.txt

+2 −2
Original line number Diff line number Diff line
@@ -144,7 +144,7 @@ On x86-64, x86-64-unrolled, x86-64-movsq and x86-64-movsb are supported. 
Repeat memcpy invocation this number of times.



-c::

--clock::

--cycle::

Use perf's cpu-cycles event instead of gettimeofday syscall.



-o::
@@ -176,7 +176,7 @@ On x86-64, x86-64-unrolled, x86-64-stosq and x86-64-stosb are supported. 
Repeat memset invocation this number of times.



-c::

--clock::

--cycle::

Use perf's cpu-cycles event instead of gettimeofday syscall.



-o::

tools/perf/bench/mem-memcpy.c

+40 −40
Original line number Diff line number Diff line
@@ -24,8 +24,8 @@ 
static const char	*length_str	= "1MB";

static const char	*routine	= "default";

static int		iterations	= 1;

static bool		use_clock;

static int		clock_fd;

static bool		use_cycle;

static int		cycle_fd;

static bool		only_prefault;

static bool		no_prefault;
@@ -37,7 +37,7 @@ static const struct option options[] = { 
		    "Specify routine to copy"),

	OPT_INTEGER('i', "iterations", &iterations,

		    "repeat memcpy() invocation this number of times"),

	OPT_BOOLEAN('c', "clock", &use_clock,

	OPT_BOOLEAN('c', "cycle", &use_cycle,

		    "Use cycles event instead of gettimeofday() for measuring"),

	OPT_BOOLEAN('o', "only-prefault", &only_prefault,

		    "Show only the result with page faults before memcpy()"),
@@ -76,27 +76,27 @@ static const char * const bench_mem_memcpy_usage[] = { 
	NULL

};



static struct perf_event_attr clock_attr = {

static struct perf_event_attr cycle_attr = {

	.type		= PERF_TYPE_HARDWARE,

	.config		= PERF_COUNT_HW_CPU_CYCLES

};



static void init_clock(void)

static void init_cycle(void)

{

	clock_fd = sys_perf_event_open(&clock_attr, getpid(), -1, -1, 0);

	cycle_fd = sys_perf_event_open(&cycle_attr, getpid(), -1, -1, 0);



	if (clock_fd < 0 && errno == ENOSYS)

	if (cycle_fd < 0 && errno == ENOSYS)

		die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");

	else

		BUG_ON(clock_fd < 0);

		BUG_ON(cycle_fd < 0);

}



static u64 get_clock(void)

static u64 get_cycle(void)

{

	int ret;

	u64 clk;



	ret = read(clock_fd, &clk, sizeof(u64));

	ret = read(cycle_fd, &clk, sizeof(u64));

	BUG_ON(ret != sizeof(u64));



	return clk;
@@ -119,9 +119,9 @@ static void alloc_mem(void **dst, void **src, size_t length) 
		die("memory allocation failed - maybe length is too large?\n");

}



static u64 do_memcpy_clock(memcpy_t fn, size_t len, bool prefault)

static u64 do_memcpy_cycle(memcpy_t fn, size_t len, bool prefault)

{

	u64 clock_start = 0ULL, clock_end = 0ULL;

	u64 cycle_start = 0ULL, cycle_end = 0ULL;

	void *src = NULL, *dst = NULL;

	int i;
@@ -130,14 +130,14 @@ static u64 do_memcpy_clock(memcpy_t fn, size_t len, bool prefault) 
	if (prefault)

		fn(dst, src, len);



	clock_start = get_clock();

	cycle_start = get_cycle();

	for (i = 0; i < iterations; ++i)

		fn(dst, src, len);

	clock_end = get_clock();

	cycle_end = get_cycle();



	free(src);

	free(dst);

	return clock_end - clock_start;

	return cycle_end - cycle_start;

}



static double do_memcpy_gettimeofday(memcpy_t fn, size_t len, bool prefault)
@@ -182,17 +182,17 @@ int bench_mem_memcpy(int argc, const char **argv, 
	int i;

	size_t len;

	double result_bps[2];

	u64 result_clock[2];

	u64 result_cycle[2];



	argc = parse_options(argc, argv, options,

			     bench_mem_memcpy_usage, 0);



	if (use_clock)

		init_clock();

	if (use_cycle)

		init_cycle();



	len = (size_t)perf_atoll((char *)length_str);



	result_clock[0] = result_clock[1] = 0ULL;

	result_cycle[0] = result_cycle[1] = 0ULL;

	result_bps[0] = result_bps[1] = 0.0;



	if ((s64)len <= 0) {
@@ -223,11 +223,11 @@ int bench_mem_memcpy(int argc, const char **argv, 


	if (!only_prefault && !no_prefault) {

		/* show both of results */

		if (use_clock) {

			result_clock[0] =

				do_memcpy_clock(routines[i].fn, len, false);

			result_clock[1] =

				do_memcpy_clock(routines[i].fn, len, true);

		if (use_cycle) {

			result_cycle[0] =

				do_memcpy_cycle(routines[i].fn, len, false);

			result_cycle[1] =

				do_memcpy_cycle(routines[i].fn, len, true);

		} else {

			result_bps[0] =

				do_memcpy_gettimeofday(routines[i].fn,
@@ -237,9 +237,9 @@ int bench_mem_memcpy(int argc, const char **argv, 
						len, true);

		}

	} else {

		if (use_clock) {

			result_clock[pf] =

				do_memcpy_clock(routines[i].fn,

		if (use_cycle) {

			result_cycle[pf] =

				do_memcpy_cycle(routines[i].fn,

						len, only_prefault);

		} else {

			result_bps[pf] =
@@ -251,12 +251,12 @@ int bench_mem_memcpy(int argc, const char **argv, 
	switch (bench_format) {

	case BENCH_FORMAT_DEFAULT:

		if (!only_prefault && !no_prefault) {

			if (use_clock) {

				printf(" %14lf Clock/Byte\n",

					(double)result_clock[0]

			if (use_cycle) {

				printf(" %14lf Cycle/Byte\n",

					(double)result_cycle[0]

					/ (double)len);

				printf(" %14lf Clock/Byte (with prefault)\n",

					(double)result_clock[1]

				printf(" %14lf Cycle/Byte (with prefault)\n",

					(double)result_cycle[1]

					/ (double)len);

			} else {

				print_bps(result_bps[0]);
@@ -265,9 +265,9 @@ int bench_mem_memcpy(int argc, const char **argv, 
				printf(" (with prefault)\n");

			}

		} else {

			if (use_clock) {

				printf(" %14lf Clock/Byte",

					(double)result_clock[pf]

			if (use_cycle) {

				printf(" %14lf Cycle/Byte",

					(double)result_cycle[pf]

					/ (double)len);

			} else

				print_bps(result_bps[pf]);
@@ -277,17 +277,17 @@ int bench_mem_memcpy(int argc, const char **argv, 
		break;

	case BENCH_FORMAT_SIMPLE:

		if (!only_prefault && !no_prefault) {

			if (use_clock) {

			if (use_cycle) {

				printf("%lf %lf\n",

					(double)result_clock[0] / (double)len,

					(double)result_clock[1] / (double)len);

					(double)result_cycle[0] / (double)len,

					(double)result_cycle[1] / (double)len);

			} else {

				printf("%lf %lf\n",

					result_bps[0], result_bps[1]);

			}

		} else {

			if (use_clock) {

				printf("%lf\n", (double)result_clock[pf]

			if (use_cycle) {

				printf("%lf\n", (double)result_cycle[pf]

					/ (double)len);

			} else

				printf("%lf\n", result_bps[pf]);

tools/perf/bench/mem-memset.c

+40 −40
Original line number Diff line number Diff line
@@ -24,8 +24,8 @@ 
static const char	*length_str	= "1MB";

static const char	*routine	= "default";

static int		iterations	= 1;

static bool		use_clock;

static int		clock_fd;

static bool		use_cycle;

static int		cycle_fd;

static bool		only_prefault;

static bool		no_prefault;
@@ -37,7 +37,7 @@ static const struct option options[] = { 
		    "Specify routine to set"),

	OPT_INTEGER('i', "iterations", &iterations,

		    "repeat memset() invocation this number of times"),

	OPT_BOOLEAN('c', "clock", &use_clock,

	OPT_BOOLEAN('c', "cycle", &use_cycle,

		    "Use cycles event instead of gettimeofday() for measuring"),

	OPT_BOOLEAN('o', "only-prefault", &only_prefault,

		    "Show only the result with page faults before memset()"),
@@ -76,27 +76,27 @@ static const char * const bench_mem_memset_usage[] = { 
	NULL

};



static struct perf_event_attr clock_attr = {

static struct perf_event_attr cycle_attr = {

	.type		= PERF_TYPE_HARDWARE,

	.config		= PERF_COUNT_HW_CPU_CYCLES

};



static void init_clock(void)

static void init_cycle(void)

{

	clock_fd = sys_perf_event_open(&clock_attr, getpid(), -1, -1, 0);

	cycle_fd = sys_perf_event_open(&cycle_attr, getpid(), -1, -1, 0);



	if (clock_fd < 0 && errno == ENOSYS)

	if (cycle_fd < 0 && errno == ENOSYS)

		die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");

	else

		BUG_ON(clock_fd < 0);

		BUG_ON(cycle_fd < 0);

}



static u64 get_clock(void)

static u64 get_cycle(void)

{

	int ret;

	u64 clk;



	ret = read(clock_fd, &clk, sizeof(u64));

	ret = read(cycle_fd, &clk, sizeof(u64));

	BUG_ON(ret != sizeof(u64));



	return clk;
@@ -115,9 +115,9 @@ static void alloc_mem(void **dst, size_t length) 
		die("memory allocation failed - maybe length is too large?\n");

}



static u64 do_memset_clock(memset_t fn, size_t len, bool prefault)

static u64 do_memset_cycle(memset_t fn, size_t len, bool prefault)

{

	u64 clock_start = 0ULL, clock_end = 0ULL;

	u64 cycle_start = 0ULL, cycle_end = 0ULL;

	void *dst = NULL;

	int i;
@@ -126,13 +126,13 @@ static u64 do_memset_clock(memset_t fn, size_t len, bool prefault) 
	if (prefault)

		fn(dst, -1, len);



	clock_start = get_clock();

	cycle_start = get_cycle();

	for (i = 0; i < iterations; ++i)

		fn(dst, i, len);

	clock_end = get_clock();

	cycle_end = get_cycle();



	free(dst);

	return clock_end - clock_start;

	return cycle_end - cycle_start;

}



static double do_memset_gettimeofday(memset_t fn, size_t len, bool prefault)
@@ -176,17 +176,17 @@ int bench_mem_memset(int argc, const char **argv, 
	int i;

	size_t len;

	double result_bps[2];

	u64 result_clock[2];

	u64 result_cycle[2];



	argc = parse_options(argc, argv, options,

			     bench_mem_memset_usage, 0);



	if (use_clock)

		init_clock();

	if (use_cycle)

		init_cycle();



	len = (size_t)perf_atoll((char *)length_str);



	result_clock[0] = result_clock[1] = 0ULL;

	result_cycle[0] = result_cycle[1] = 0ULL;

	result_bps[0] = result_bps[1] = 0.0;



	if ((s64)len <= 0) {
@@ -217,11 +217,11 @@ int bench_mem_memset(int argc, const char **argv, 


	if (!only_prefault && !no_prefault) {

		/* show both of results */

		if (use_clock) {

			result_clock[0] =

				do_memset_clock(routines[i].fn, len, false);

			result_clock[1] =

				do_memset_clock(routines[i].fn, len, true);

		if (use_cycle) {

			result_cycle[0] =

				do_memset_cycle(routines[i].fn, len, false);

			result_cycle[1] =

				do_memset_cycle(routines[i].fn, len, true);

		} else {

			result_bps[0] =

				do_memset_gettimeofday(routines[i].fn,
@@ -231,9 +231,9 @@ int bench_mem_memset(int argc, const char **argv, 
						len, true);

		}

	} else {

		if (use_clock) {

			result_clock[pf] =

				do_memset_clock(routines[i].fn,

		if (use_cycle) {

			result_cycle[pf] =

				do_memset_cycle(routines[i].fn,

						len, only_prefault);

		} else {

			result_bps[pf] =
@@ -245,12 +245,12 @@ int bench_mem_memset(int argc, const char **argv, 
	switch (bench_format) {

	case BENCH_FORMAT_DEFAULT:

		if (!only_prefault && !no_prefault) {

			if (use_clock) {

				printf(" %14lf Clock/Byte\n",

					(double)result_clock[0]

			if (use_cycle) {

				printf(" %14lf Cycle/Byte\n",

					(double)result_cycle[0]

					/ (double)len);

				printf(" %14lf Clock/Byte (with prefault)\n ",

					(double)result_clock[1]

				printf(" %14lf Cycle/Byte (with prefault)\n ",

					(double)result_cycle[1]

					/ (double)len);

			} else {

				print_bps(result_bps[0]);
@@ -259,9 +259,9 @@ int bench_mem_memset(int argc, const char **argv, 
				printf(" (with prefault)\n");

			}

		} else {

			if (use_clock) {

				printf(" %14lf Clock/Byte",

					(double)result_clock[pf]

			if (use_cycle) {

				printf(" %14lf Cycle/Byte",

					(double)result_cycle[pf]

					/ (double)len);

			} else

				print_bps(result_bps[pf]);
@@ -271,17 +271,17 @@ int bench_mem_memset(int argc, const char **argv, 
		break;

	case BENCH_FORMAT_SIMPLE:

		if (!only_prefault && !no_prefault) {

			if (use_clock) {

			if (use_cycle) {

				printf("%lf %lf\n",

					(double)result_clock[0] / (double)len,

					(double)result_clock[1] / (double)len);

					(double)result_cycle[0] / (double)len,

					(double)result_cycle[1] / (double)len);

			} else {

				printf("%lf %lf\n",

					result_bps[0], result_bps[1]);

			}

		} else {

			if (use_clock) {

				printf("%lf\n", (double)result_clock[pf]

			if (use_cycle) {

				printf("%lf\n", (double)result_cycle[pf]

					/ (double)len);

			} else

				printf("%lf\n", result_bps[pf]);

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