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perf events: Change perf parameter --pid to process-wide collection i…
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…nstead of thread-wide

Parameter --pid (or -p) of perf currently means a thread-wide
collection. For exmaple, if a process whose id is 8888 has 10
threads, 'perf top -p 8888' just collects the main thread
statistics. That's misleading. Users are used to attach a whole
process when debugging a process by gdb. To follow normal usage
style, the patch change --pid to process-wide collection and add
--tid (-t) to mean a thread-wide collection.

Usage example is:

 # perf top -p 8888
 # perf record -p 8888 -f sleep 10
 # perf stat -p 8888 -f sleep 10

Above commands collect the statistics of all threads of process
8888.

Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sheng Yang <sheng@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jes Sorensen <Jes.Sorensen@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: zhiteng.huang@intel.com
Cc: Zachary Amsden <zamsden@redhat.com>
LKML-Reference: <1268922965-14774-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Zhang, Yanmin authored and Ingo Molnar committed Mar 18, 2010
1 parent 46be604 commit d6d901c
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Showing 5 changed files with 372 additions and 193 deletions.
260 changes: 159 additions & 101 deletions tools/perf/builtin-record.c
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Original file line number Diff line number Diff line change
Expand Up @@ -27,7 +27,7 @@
#include <unistd.h>
#include <sched.h>

static int fd[MAX_NR_CPUS][MAX_COUNTERS];
static int *fd[MAX_NR_CPUS][MAX_COUNTERS];

static long default_interval = 0;

Expand All @@ -43,6 +43,9 @@ static int raw_samples = 0;
static int system_wide = 0;
static int profile_cpu = -1;
static pid_t target_pid = -1;
static pid_t target_tid = -1;
static pid_t *all_tids = NULL;
static int thread_num = 0;
static pid_t child_pid = -1;
static int inherit = 1;
static int force = 0;
Expand All @@ -60,7 +63,7 @@ static struct timeval this_read;

static u64 bytes_written = 0;

static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
static struct pollfd *event_array;

static int nr_poll = 0;
static int nr_cpu = 0;
Expand All @@ -77,7 +80,7 @@ struct mmap_data {
unsigned int prev;
};

static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
static struct mmap_data *mmap_array[MAX_NR_CPUS][MAX_COUNTERS];

static unsigned long mmap_read_head(struct mmap_data *md)
{
Expand Down Expand Up @@ -225,12 +228,13 @@ static struct perf_header_attr *get_header_attr(struct perf_event_attr *a, int n
return h_attr;
}

static void create_counter(int counter, int cpu, pid_t pid)
static void create_counter(int counter, int cpu)
{
char *filter = filters[counter];
struct perf_event_attr *attr = attrs + counter;
struct perf_header_attr *h_attr;
int track = !counter; /* only the first counter needs these */
int thread_index;
int ret;
struct {
u64 count;
Expand Down Expand Up @@ -280,115 +284,124 @@ static void create_counter(int counter, int cpu, pid_t pid)
attr->enable_on_exec = 1;
}

for (thread_index = 0; thread_index < thread_num; thread_index++) {
try_again:
fd[nr_cpu][counter] = sys_perf_event_open(attr, pid, cpu, group_fd, 0);

if (fd[nr_cpu][counter] < 0) {
int err = errno;

if (err == EPERM || err == EACCES)
die("Permission error - are you root?\n"
"\t Consider tweaking /proc/sys/kernel/perf_event_paranoid.\n");
else if (err == ENODEV && profile_cpu != -1)
die("No such device - did you specify an out-of-range profile CPU?\n");
fd[nr_cpu][counter][thread_index] = sys_perf_event_open(attr,
all_tids[thread_index], cpu, group_fd, 0);

if (fd[nr_cpu][counter][thread_index] < 0) {
int err = errno;

if (err == EPERM || err == EACCES)
die("Permission error - are you root?\n"
"\t Consider tweaking"
" /proc/sys/kernel/perf_event_paranoid.\n");
else if (err == ENODEV && profile_cpu != -1) {
die("No such device - did you specify"
" an out-of-range profile CPU?\n");
}

/*
* If it's cycles then fall back to hrtimer
* based cpu-clock-tick sw counter, which
* is always available even if no PMU support:
*/
if (attr->type == PERF_TYPE_HARDWARE
&& attr->config == PERF_COUNT_HW_CPU_CYCLES) {

if (verbose)
warning(" ... trying to fall back to cpu-clock-ticks\n");
attr->type = PERF_TYPE_SOFTWARE;
attr->config = PERF_COUNT_SW_CPU_CLOCK;
goto try_again;
}
printf("\n");
error("perfcounter syscall returned with %d (%s)\n",
fd[nr_cpu][counter], strerror(err));
/*
* If it's cycles then fall back to hrtimer
* based cpu-clock-tick sw counter, which
* is always available even if no PMU support:
*/
if (attr->type == PERF_TYPE_HARDWARE
&& attr->config == PERF_COUNT_HW_CPU_CYCLES) {

if (verbose)
warning(" ... trying to fall back to cpu-clock-ticks\n");
attr->type = PERF_TYPE_SOFTWARE;
attr->config = PERF_COUNT_SW_CPU_CLOCK;
goto try_again;
}
printf("\n");
error("perfcounter syscall returned with %d (%s)\n",
fd[nr_cpu][counter][thread_index], strerror(err));

#if defined(__i386__) || defined(__x86_64__)
if (attr->type == PERF_TYPE_HARDWARE && err == EOPNOTSUPP)
die("No hardware sampling interrupt available. No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.\n");
if (attr->type == PERF_TYPE_HARDWARE && err == EOPNOTSUPP)
die("No hardware sampling interrupt available."
" No APIC? If so then you can boot the kernel"
" with the \"lapic\" boot parameter to"
" force-enable it.\n");
#endif

die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
exit(-1);
}
die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
exit(-1);
}

h_attr = get_header_attr(attr, counter);
if (h_attr == NULL)
die("nomem\n");
h_attr = get_header_attr(attr, counter);
if (h_attr == NULL)
die("nomem\n");

if (!file_new) {
if (memcmp(&h_attr->attr, attr, sizeof(*attr))) {
fprintf(stderr, "incompatible append\n");
exit(-1);
if (!file_new) {
if (memcmp(&h_attr->attr, attr, sizeof(*attr))) {
fprintf(stderr, "incompatible append\n");
exit(-1);
}
}
}

if (read(fd[nr_cpu][counter], &read_data, sizeof(read_data)) == -1) {
perror("Unable to read perf file descriptor\n");
exit(-1);
}
if (read(fd[nr_cpu][counter][thread_index], &read_data, sizeof(read_data)) == -1) {
perror("Unable to read perf file descriptor\n");
exit(-1);
}

if (perf_header_attr__add_id(h_attr, read_data.id) < 0) {
pr_warning("Not enough memory to add id\n");
exit(-1);
}
if (perf_header_attr__add_id(h_attr, read_data.id) < 0) {
pr_warning("Not enough memory to add id\n");
exit(-1);
}

assert(fd[nr_cpu][counter] >= 0);
fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK);
assert(fd[nr_cpu][counter][thread_index] >= 0);
fcntl(fd[nr_cpu][counter][thread_index], F_SETFL, O_NONBLOCK);

/*
* First counter acts as the group leader:
*/
if (group && group_fd == -1)
group_fd = fd[nr_cpu][counter];
if (multiplex && multiplex_fd == -1)
multiplex_fd = fd[nr_cpu][counter];
/*
* First counter acts as the group leader:
*/
if (group && group_fd == -1)
group_fd = fd[nr_cpu][counter][thread_index];
if (multiplex && multiplex_fd == -1)
multiplex_fd = fd[nr_cpu][counter][thread_index];

if (multiplex && fd[nr_cpu][counter] != multiplex_fd) {
if (multiplex && fd[nr_cpu][counter][thread_index] != multiplex_fd) {

ret = ioctl(fd[nr_cpu][counter], PERF_EVENT_IOC_SET_OUTPUT, multiplex_fd);
assert(ret != -1);
} else {
event_array[nr_poll].fd = fd[nr_cpu][counter];
event_array[nr_poll].events = POLLIN;
nr_poll++;

mmap_array[nr_cpu][counter].counter = counter;
mmap_array[nr_cpu][counter].prev = 0;
mmap_array[nr_cpu][counter].mask = mmap_pages*page_size - 1;
mmap_array[nr_cpu][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
PROT_READ|PROT_WRITE, MAP_SHARED, fd[nr_cpu][counter], 0);
if (mmap_array[nr_cpu][counter].base == MAP_FAILED) {
error("failed to mmap with %d (%s)\n", errno, strerror(errno));
exit(-1);
ret = ioctl(fd[nr_cpu][counter][thread_index], PERF_EVENT_IOC_SET_OUTPUT, multiplex_fd);
assert(ret != -1);
} else {
event_array[nr_poll].fd = fd[nr_cpu][counter][thread_index];
event_array[nr_poll].events = POLLIN;
nr_poll++;

mmap_array[nr_cpu][counter][thread_index].counter = counter;
mmap_array[nr_cpu][counter][thread_index].prev = 0;
mmap_array[nr_cpu][counter][thread_index].mask = mmap_pages*page_size - 1;
mmap_array[nr_cpu][counter][thread_index].base = mmap(NULL, (mmap_pages+1)*page_size,
PROT_READ|PROT_WRITE, MAP_SHARED, fd[nr_cpu][counter][thread_index], 0);
if (mmap_array[nr_cpu][counter][thread_index].base == MAP_FAILED) {
error("failed to mmap with %d (%s)\n", errno, strerror(errno));
exit(-1);
}
}
}

if (filter != NULL) {
ret = ioctl(fd[nr_cpu][counter],
PERF_EVENT_IOC_SET_FILTER, filter);
if (ret) {
error("failed to set filter with %d (%s)\n", errno,
strerror(errno));
exit(-1);
if (filter != NULL) {
ret = ioctl(fd[nr_cpu][counter][thread_index],
PERF_EVENT_IOC_SET_FILTER, filter);
if (ret) {
error("failed to set filter with %d (%s)\n", errno,
strerror(errno));
exit(-1);
}
}
}
}

static void open_counters(int cpu, pid_t pid)
static void open_counters(int cpu)
{
int counter;

group_fd = -1;
for (counter = 0; counter < nr_counters; counter++)
create_counter(counter, cpu, pid);
create_counter(counter, cpu);

nr_cpu++;
}
Expand Down Expand Up @@ -529,6 +542,9 @@ static int __cmd_record(int argc, const char **argv)
exit(-1);
}

if (!system_wide && target_tid == -1 && target_pid == -1)
all_tids[0] = child_pid;

close(child_ready_pipe[1]);
close(go_pipe[0]);
/*
Expand All @@ -541,17 +557,12 @@ static int __cmd_record(int argc, const char **argv)
close(child_ready_pipe[0]);
}

if (forks && target_pid == -1 && !system_wide)
pid = child_pid;
else
pid = target_pid;

if ((!system_wide && !inherit) || profile_cpu != -1) {
open_counters(profile_cpu, pid);
open_counters(profile_cpu);
} else {
nr_cpus = read_cpu_map();
for (i = 0; i < nr_cpus; i++)
open_counters(cpumap[i], pid);
open_counters(cpumap[i]);
}

if (file_new) {
Expand All @@ -576,7 +587,7 @@ static int __cmd_record(int argc, const char **argv)
}

if (!system_wide && profile_cpu == -1)
event__synthesize_thread(target_pid, process_synthesized_event,
event__synthesize_thread(target_tid, process_synthesized_event,
session);
else
event__synthesize_threads(process_synthesized_event, session);
Expand All @@ -599,11 +610,16 @@ static int __cmd_record(int argc, const char **argv)

for (;;) {
int hits = samples;
int thread;

for (i = 0; i < nr_cpu; i++) {
for (counter = 0; counter < nr_counters; counter++) {
if (mmap_array[i][counter].base)
mmap_read(&mmap_array[i][counter]);
for (thread = 0;
thread < thread_num; thread++) {
if (mmap_array[i][counter][thread].base)
mmap_read(&mmap_array[i][counter][thread]);
}

}
}

Expand All @@ -616,8 +632,15 @@ static int __cmd_record(int argc, const char **argv)

if (done) {
for (i = 0; i < nr_cpu; i++) {
for (counter = 0; counter < nr_counters; counter++)
ioctl(fd[i][counter], PERF_EVENT_IOC_DISABLE);
for (counter = 0;
counter < nr_counters;
counter++) {
for (thread = 0;
thread < thread_num;
thread++)
ioctl(fd[i][counter][thread],
PERF_EVENT_IOC_DISABLE);
}
}
}
}
Expand Down Expand Up @@ -649,7 +672,9 @@ static const struct option options[] = {
OPT_CALLBACK(0, "filter", NULL, "filter",
"event filter", parse_filter),
OPT_INTEGER('p', "pid", &target_pid,
"record events on existing pid"),
"record events on existing process id"),
OPT_INTEGER('t', "tid", &target_tid,
"record events on existing thread id"),
OPT_INTEGER('r', "realtime", &realtime_prio,
"collect data with this RT SCHED_FIFO priority"),
OPT_BOOLEAN('R', "raw-samples", &raw_samples,
Expand Down Expand Up @@ -690,10 +715,12 @@ static const struct option options[] = {
int cmd_record(int argc, const char **argv, const char *prefix __used)
{
int counter;
int i,j;

argc = parse_options(argc, argv, options, record_usage,
PARSE_OPT_STOP_AT_NON_OPTION);
if (!argc && target_pid == -1 && !system_wide && profile_cpu == -1)
if (!argc && target_pid == -1 && target_tid == -1 &&
!system_wide && profile_cpu == -1)
usage_with_options(record_usage, options);

symbol__init();
Expand All @@ -704,6 +731,37 @@ int cmd_record(int argc, const char **argv, const char *prefix __used)
attrs[0].config = PERF_COUNT_HW_CPU_CYCLES;
}

if (target_pid != -1) {
target_tid = target_pid;
thread_num = find_all_tid(target_pid, &all_tids);
if (thread_num <= 0) {
fprintf(stderr, "Can't find all threads of pid %d\n",
target_pid);
usage_with_options(record_usage, options);
}
} else {
all_tids=malloc(sizeof(pid_t));
if (!all_tids)
return -ENOMEM;

all_tids[0] = target_tid;
thread_num = 1;
}

for (i = 0; i < MAX_NR_CPUS; i++) {
for (j = 0; j < MAX_COUNTERS; j++) {
fd[i][j] = malloc(sizeof(int)*thread_num);
mmap_array[i][j] = malloc(
sizeof(struct mmap_data)*thread_num);
if (!fd[i][j] || !mmap_array[i][j])
return -ENOMEM;
}
}
event_array = malloc(
sizeof(struct pollfd)*MAX_NR_CPUS*MAX_COUNTERS*thread_num);
if (!event_array)
return -ENOMEM;

/*
* User specified count overrides default frequency.
*/
Expand Down
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