perf evsel: Fix use of inherit
perf stat doesn't mmap and its perfectly fine for it to use task-bound counters with inheritance. So set the attr.inherit on the caller and leave the syscall itself to validate it. When the mmap fails perf_evlist__mmap will just emit a warning if this is the failure reason. Reported-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> Link: http://lkml.kernel.org/r/20110414170121.GC3229@ghostprotocols.net Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
parent
db9a9cbc81
commit
5d2cd90922
|
@ -163,6 +163,7 @@ static void config_attr(struct perf_evsel *evsel, struct perf_evlist *evlist)
|
|||
struct perf_event_attr *attr = &evsel->attr;
|
||||
int track = !evsel->idx; /* only the first counter needs these */
|
||||
|
||||
attr->inherit = !no_inherit;
|
||||
attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
|
||||
PERF_FORMAT_TOTAL_TIME_RUNNING |
|
||||
PERF_FORMAT_ID;
|
||||
|
@ -251,6 +252,9 @@ static void open_counters(struct perf_evlist *evlist)
|
|||
{
|
||||
struct perf_evsel *pos;
|
||||
|
||||
if (evlist->cpus->map[0] < 0)
|
||||
no_inherit = true;
|
||||
|
||||
list_for_each_entry(pos, &evlist->entries, node) {
|
||||
struct perf_event_attr *attr = &pos->attr;
|
||||
/*
|
||||
|
@ -271,8 +275,7 @@ static void open_counters(struct perf_evlist *evlist)
|
|||
retry_sample_id:
|
||||
attr->sample_id_all = sample_id_all_avail ? 1 : 0;
|
||||
try_again:
|
||||
if (perf_evsel__open(pos, evlist->cpus, evlist->threads, group,
|
||||
!no_inherit) < 0) {
|
||||
if (perf_evsel__open(pos, evlist->cpus, evlist->threads, group) < 0) {
|
||||
int err = errno;
|
||||
|
||||
if (err == EPERM || err == EACCES) {
|
||||
|
|
|
@ -167,16 +167,17 @@ static int create_perf_stat_counter(struct perf_evsel *evsel)
|
|||
attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
|
||||
PERF_FORMAT_TOTAL_TIME_RUNNING;
|
||||
|
||||
if (system_wide)
|
||||
return perf_evsel__open_per_cpu(evsel, evsel_list->cpus, false, false);
|
||||
|
||||
attr->inherit = !no_inherit;
|
||||
|
||||
if (system_wide)
|
||||
return perf_evsel__open_per_cpu(evsel, evsel_list->cpus, false);
|
||||
|
||||
if (target_pid == -1 && target_tid == -1) {
|
||||
attr->disabled = 1;
|
||||
attr->enable_on_exec = 1;
|
||||
}
|
||||
|
||||
return perf_evsel__open_per_thread(evsel, evsel_list->threads, false, false);
|
||||
return perf_evsel__open_per_thread(evsel, evsel_list->threads, false);
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
|
@ -290,7 +290,7 @@ static int test__open_syscall_event(void)
|
|||
goto out_thread_map_delete;
|
||||
}
|
||||
|
||||
if (perf_evsel__open_per_thread(evsel, threads, false, false) < 0) {
|
||||
if (perf_evsel__open_per_thread(evsel, threads, false) < 0) {
|
||||
pr_debug("failed to open counter: %s, "
|
||||
"tweak /proc/sys/kernel/perf_event_paranoid?\n",
|
||||
strerror(errno));
|
||||
|
@ -303,7 +303,7 @@ static int test__open_syscall_event(void)
|
|||
}
|
||||
|
||||
if (perf_evsel__read_on_cpu(evsel, 0, 0) < 0) {
|
||||
pr_debug("perf_evsel__open_read_on_cpu\n");
|
||||
pr_debug("perf_evsel__read_on_cpu\n");
|
||||
goto out_close_fd;
|
||||
}
|
||||
|
||||
|
@ -365,7 +365,7 @@ static int test__open_syscall_event_on_all_cpus(void)
|
|||
goto out_thread_map_delete;
|
||||
}
|
||||
|
||||
if (perf_evsel__open(evsel, cpus, threads, false, false) < 0) {
|
||||
if (perf_evsel__open(evsel, cpus, threads, false) < 0) {
|
||||
pr_debug("failed to open counter: %s, "
|
||||
"tweak /proc/sys/kernel/perf_event_paranoid?\n",
|
||||
strerror(errno));
|
||||
|
@ -418,7 +418,7 @@ static int test__open_syscall_event_on_all_cpus(void)
|
|||
continue;
|
||||
|
||||
if (perf_evsel__read_on_cpu(evsel, cpu, 0) < 0) {
|
||||
pr_debug("perf_evsel__open_read_on_cpu\n");
|
||||
pr_debug("perf_evsel__read_on_cpu\n");
|
||||
err = -1;
|
||||
break;
|
||||
}
|
||||
|
@ -529,7 +529,7 @@ static int test__basic_mmap(void)
|
|||
|
||||
perf_evlist__add(evlist, evsels[i]);
|
||||
|
||||
if (perf_evsel__open(evsels[i], cpus, threads, false, false) < 0) {
|
||||
if (perf_evsel__open(evsels[i], cpus, threads, false) < 0) {
|
||||
pr_debug("failed to open counter: %s, "
|
||||
"tweak /proc/sys/kernel/perf_event_paranoid?\n",
|
||||
strerror(errno));
|
||||
|
|
|
@ -845,9 +845,10 @@ static void start_counters(struct perf_evlist *evlist)
|
|||
}
|
||||
|
||||
attr->mmap = 1;
|
||||
attr->inherit = inherit;
|
||||
try_again:
|
||||
if (perf_evsel__open(counter, top.evlist->cpus,
|
||||
top.evlist->threads, group, inherit) < 0) {
|
||||
top.evlist->threads, group) < 0) {
|
||||
int err = errno;
|
||||
|
||||
if (err == EPERM || err == EACCES) {
|
||||
|
|
|
@ -12,6 +12,7 @@
|
|||
#include "evlist.h"
|
||||
#include "evsel.h"
|
||||
#include "util.h"
|
||||
#include "debug.h"
|
||||
|
||||
#include <sys/mman.h>
|
||||
|
||||
|
@ -250,15 +251,19 @@ int perf_evlist__alloc_mmap(struct perf_evlist *evlist)
|
|||
return evlist->mmap != NULL ? 0 : -ENOMEM;
|
||||
}
|
||||
|
||||
static int __perf_evlist__mmap(struct perf_evlist *evlist, int cpu, int prot,
|
||||
int mask, int fd)
|
||||
static int __perf_evlist__mmap(struct perf_evlist *evlist, struct perf_evsel *evsel,
|
||||
int cpu, int prot, int mask, int fd)
|
||||
{
|
||||
evlist->mmap[cpu].prev = 0;
|
||||
evlist->mmap[cpu].mask = mask;
|
||||
evlist->mmap[cpu].base = mmap(NULL, evlist->mmap_len, prot,
|
||||
MAP_SHARED, fd, 0);
|
||||
if (evlist->mmap[cpu].base == MAP_FAILED)
|
||||
if (evlist->mmap[cpu].base == MAP_FAILED) {
|
||||
if (evlist->cpus->map[cpu] == -1 && evsel->attr.inherit)
|
||||
ui__warning("Inherit is not allowed on per-task "
|
||||
"events using mmap.\n");
|
||||
return -1;
|
||||
}
|
||||
|
||||
perf_evlist__add_pollfd(evlist, fd);
|
||||
return 0;
|
||||
|
@ -312,7 +317,8 @@ int perf_evlist__mmap(struct perf_evlist *evlist, int pages, bool overwrite)
|
|||
if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT,
|
||||
FD(first_evsel, cpu, 0)) != 0)
|
||||
goto out_unmap;
|
||||
} else if (__perf_evlist__mmap(evlist, cpu, prot, mask, fd) < 0)
|
||||
} else if (__perf_evlist__mmap(evlist, evsel, cpu,
|
||||
prot, mask, fd) < 0)
|
||||
goto out_unmap;
|
||||
|
||||
if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
|
||||
|
|
|
@ -175,7 +175,7 @@ int __perf_evsel__read(struct perf_evsel *evsel,
|
|||
}
|
||||
|
||||
static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
|
||||
struct thread_map *threads, bool group, bool inherit)
|
||||
struct thread_map *threads, bool group)
|
||||
{
|
||||
int cpu, thread;
|
||||
unsigned long flags = 0;
|
||||
|
@ -192,19 +192,6 @@ static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
|
|||
|
||||
for (cpu = 0; cpu < cpus->nr; cpu++) {
|
||||
int group_fd = -1;
|
||||
/*
|
||||
* Don't allow mmap() of inherited per-task counters. This
|
||||
* would create a performance issue due to all children writing
|
||||
* to the same buffer.
|
||||
*
|
||||
* FIXME:
|
||||
* Proper fix is not to pass 'inherit' to perf_evsel__open*,
|
||||
* but a 'flags' parameter, with 'group' folded there as well,
|
||||
* then introduce a PERF_O_{MMAP,GROUP,INHERIT} enum, and if
|
||||
* O_MMAP is set, emit a warning if cpu < 0 and O_INHERIT is
|
||||
* set. Lets go for the minimal fix first tho.
|
||||
*/
|
||||
evsel->attr.inherit = (cpus->map[cpu] >= 0) && inherit;
|
||||
|
||||
for (thread = 0; thread < threads->nr; thread++) {
|
||||
|
||||
|
@ -253,7 +240,7 @@ static struct {
|
|||
};
|
||||
|
||||
int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
|
||||
struct thread_map *threads, bool group, bool inherit)
|
||||
struct thread_map *threads, bool group)
|
||||
{
|
||||
if (cpus == NULL) {
|
||||
/* Work around old compiler warnings about strict aliasing */
|
||||
|
@ -263,19 +250,19 @@ int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
|
|||
if (threads == NULL)
|
||||
threads = &empty_thread_map.map;
|
||||
|
||||
return __perf_evsel__open(evsel, cpus, threads, group, inherit);
|
||||
return __perf_evsel__open(evsel, cpus, threads, group);
|
||||
}
|
||||
|
||||
int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
|
||||
struct cpu_map *cpus, bool group, bool inherit)
|
||||
struct cpu_map *cpus, bool group)
|
||||
{
|
||||
return __perf_evsel__open(evsel, cpus, &empty_thread_map.map, group, inherit);
|
||||
return __perf_evsel__open(evsel, cpus, &empty_thread_map.map, group);
|
||||
}
|
||||
|
||||
int perf_evsel__open_per_thread(struct perf_evsel *evsel,
|
||||
struct thread_map *threads, bool group, bool inherit)
|
||||
struct thread_map *threads, bool group)
|
||||
{
|
||||
return __perf_evsel__open(evsel, &empty_cpu_map.map, threads, group, inherit);
|
||||
return __perf_evsel__open(evsel, &empty_cpu_map.map, threads, group);
|
||||
}
|
||||
|
||||
static int perf_event__parse_id_sample(const union perf_event *event, u64 type,
|
||||
|
|
|
@ -81,11 +81,11 @@ void perf_evsel__free_id(struct perf_evsel *evsel);
|
|||
void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads);
|
||||
|
||||
int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
|
||||
struct cpu_map *cpus, bool group, bool inherit);
|
||||
struct cpu_map *cpus, bool group);
|
||||
int perf_evsel__open_per_thread(struct perf_evsel *evsel,
|
||||
struct thread_map *threads, bool group, bool inherit);
|
||||
struct thread_map *threads, bool group);
|
||||
int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
|
||||
struct thread_map *threads, bool group, bool inherit);
|
||||
struct thread_map *threads, bool group);
|
||||
|
||||
#define perf_evsel__match(evsel, t, c) \
|
||||
(evsel->attr.type == PERF_TYPE_##t && \
|
||||
|
|
|
@ -498,11 +498,11 @@ static PyObject *pyrf_evsel__open(struct pyrf_evsel *pevsel,
|
|||
struct cpu_map *cpus = NULL;
|
||||
struct thread_map *threads = NULL;
|
||||
PyObject *pcpus = NULL, *pthreads = NULL;
|
||||
int group = 0, overwrite = 0;
|
||||
static char *kwlist[] = {"cpus", "threads", "group", "overwrite", NULL, NULL};
|
||||
int group = 0, inherit = 0;
|
||||
static char *kwlist[] = {"cpus", "threads", "group", "inherit", NULL, NULL};
|
||||
|
||||
if (!PyArg_ParseTupleAndKeywords(args, kwargs, "|OOii", kwlist,
|
||||
&pcpus, &pthreads, &group, &overwrite))
|
||||
&pcpus, &pthreads, &group, &inherit))
|
||||
return NULL;
|
||||
|
||||
if (pthreads != NULL)
|
||||
|
@ -511,7 +511,8 @@ static PyObject *pyrf_evsel__open(struct pyrf_evsel *pevsel,
|
|||
if (pcpus != NULL)
|
||||
cpus = ((struct pyrf_cpu_map *)pcpus)->cpus;
|
||||
|
||||
if (perf_evsel__open(evsel, cpus, threads, group, overwrite) < 0) {
|
||||
evsel->attr.inherit = inherit;
|
||||
if (perf_evsel__open(evsel, cpus, threads, group) < 0) {
|
||||
PyErr_SetFromErrno(PyExc_OSError);
|
||||
return NULL;
|
||||
}
|
||||
|
|
Loading…
Reference in New Issue