[PATCH 02/29] perf evlist: Adopt the pollfd array

From: Arnaldo Carvalho de Melo
Date: Tue Jan 25 2011 - 12:28:07 EST


From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

Allocating just the space needed for nr_cpus * nr_threads * nr_evsels,
not the MAX_NR_CPUS and counters.

LKML-Reference: <new-submission>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Tom Zanussi <tzanussi@xxxxxxxxx>
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-record.c | 20 +++++++-------------
tools/perf/builtin-top.c | 26 +++++++++++---------------
tools/perf/util/evlist.c | 9 +++++++++
tools/perf/util/evlist.h | 6 ++++++
4 files changed, 33 insertions(+), 28 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 252ace8..1614d89 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -72,9 +72,6 @@ static struct perf_evlist *evsel_list;
static long samples = 0;
static u64 bytes_written = 0;

-static struct pollfd *event_array;
-
-static int nr_poll = 0;
static int nr_cpu = 0;

static int file_new = 1;
@@ -432,9 +429,9 @@ try_again:
exit(-1);
}

- event_array[nr_poll].fd = FD(evsel, nr_cpu, thread_index);
- event_array[nr_poll].events = POLLIN;
- nr_poll++;
+ evlist->pollfd[evlist->nr_fds].fd = FD(evsel, nr_cpu, thread_index);
+ evlist->pollfd[evlist->nr_fds].events = POLLIN;
+ evlist->nr_fds++;
}

if (filter != NULL) {
@@ -793,7 +790,7 @@ static int __cmd_record(int argc, const char **argv)
if (hits == samples) {
if (done)
break;
- err = poll(event_array, nr_poll, -1);
+ err = poll(evsel_list->pollfd, evsel_list->nr_fds, -1);
waking++;
}

@@ -948,9 +945,8 @@ int cmd_record(int argc, const char **argv, const char *prefix __used)
if (perf_header__push_event(pos->attr.config, event_name(pos)))
goto out_free_fd;
}
- event_array = malloc((sizeof(struct pollfd) * MAX_NR_CPUS *
- MAX_COUNTERS * threads->nr));
- if (!event_array)
+
+ if (perf_evlist__alloc_pollfd(evsel_list, cpus->nr, threads->nr) < 0)
goto out_free_fd;

if (user_interval != ULLONG_MAX)
@@ -968,13 +964,11 @@ int cmd_record(int argc, const char **argv, const char *prefix __used)
} else {
fprintf(stderr, "frequency and count are zero, aborting\n");
err = -EINVAL;
- goto out_free_event_array;
+ goto out_free_fd;
}

err = __cmd_record(argc, argv);

-out_free_event_array:
- free(event_array);
out_free_fd:
thread_map__delete(threads);
threads = NULL;
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 216b62e..1bc4652 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -1193,8 +1193,6 @@ static void perf_session__mmap_read_counter(struct perf_session *self,
md->prev = old;
}

-static struct pollfd *event_array;
-
static void perf_session__mmap_read(struct perf_session *self)
{
struct perf_evsel *counter;
@@ -1212,10 +1210,10 @@ static void perf_session__mmap_read(struct perf_session *self)
}
}

-int nr_poll;
int group_fd;

-static void start_counter(int i, struct perf_evsel *evsel)
+static void start_counter(int i, struct perf_evlist *evlist,
+ struct perf_evsel *evsel)
{
struct xyarray *mmap_array = evsel->priv;
struct mmap_data *mm;
@@ -1281,9 +1279,9 @@ try_again:
if (group && group_fd == -1)
group_fd = FD(evsel, i, thread_index);

- event_array[nr_poll].fd = FD(evsel, i, thread_index);
- event_array[nr_poll].events = POLLIN;
- nr_poll++;
+ evlist->pollfd[evlist->nr_fds].fd = FD(evsel, i, thread_index);
+ evlist->pollfd[evlist->nr_fds].events = POLLIN;
+ evlist->nr_fds++;

mm = xyarray__entry(mmap_array, i, thread_index);
mm->prev = 0;
@@ -1316,11 +1314,11 @@ static int __cmd_top(void)
for (i = 0; i < cpus->nr; i++) {
group_fd = -1;
list_for_each_entry(counter, &evsel_list->entries, node)
- start_counter(i, counter);
+ start_counter(i, evsel_list, counter);
}

/* Wait for a minimal set of events before starting the snapshot */
- poll(&event_array[0], nr_poll, 100);
+ poll(evsel_list->pollfd, evsel_list->nr_fds, 100);

perf_session__mmap_read(session);

@@ -1345,7 +1343,7 @@ static int __cmd_top(void)
perf_session__mmap_read(session);

if (hits == samples)
- ret = poll(event_array, nr_poll, 100);
+ ret = poll(evsel_list->pollfd, evsel_list->nr_fds, 100);
}

return 0;
@@ -1426,11 +1424,6 @@ int cmd_top(int argc, const char **argv, const char *prefix __used)
usage_with_options(top_usage, options);
}

- event_array = malloc((sizeof(struct pollfd) *
- MAX_NR_CPUS * MAX_COUNTERS * threads->nr));
- if (!event_array)
- return -ENOMEM;
-
/* CPU and PID are mutually exclusive */
if (target_tid > 0 && cpu_list) {
printf("WARNING: PID switch overriding CPU\n");
@@ -1480,6 +1473,9 @@ int cmd_top(int argc, const char **argv, const char *prefix __used)
pos->attr.sample_period = default_interval;
}

+ if (perf_evlist__alloc_pollfd(evsel_list, cpus->nr, threads->nr) < 0)
+ goto out_free_fd;
+
sym_evsel = list_entry(evsel_list->entries.next, struct perf_evsel, node);

symbol_conf.priv_size = (sizeof(struct sym_entry) +
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 7b4faec..2abf949 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -1,3 +1,4 @@
+#include <poll.h>
#include "evlist.h"
#include "evsel.h"
#include "util.h"
@@ -28,6 +29,7 @@ static void perf_evlist__purge(struct perf_evlist *evlist)
void perf_evlist__delete(struct perf_evlist *evlist)
{
perf_evlist__purge(evlist);
+ free(evlist->pollfd);
free(evlist);
}

@@ -51,3 +53,10 @@ int perf_evlist__add_default(struct perf_evlist *evlist)
perf_evlist__add(evlist, evsel);
return 0;
}
+
+int perf_evlist__alloc_pollfd(struct perf_evlist *evlist, int ncpus, int nthreads)
+{
+ int nfds = ncpus * nthreads * evlist->nr_entries;
+ evlist->pollfd = malloc(sizeof(struct pollfd) * nfds);
+ return evlist->pollfd != NULL ? 0 : -ENOMEM;
+}
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 48db91a..a7d7e12 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -3,9 +3,13 @@

#include <linux/list.h>

+struct pollfd;
+
struct perf_evlist {
struct list_head entries;
int nr_entries;
+ int nr_fds;
+ struct pollfd *pollfd;
};

struct perf_evsel;
@@ -16,4 +20,6 @@ void perf_evlist__delete(struct perf_evlist *evlist);
void perf_evlist__add(struct perf_evlist *evlist, struct perf_evsel *entry);
int perf_evlist__add_default(struct perf_evlist *evlist);

+int perf_evlist__alloc_pollfd(struct perf_evlist *evlist, int ncpus, int nthreads);
+
#endif /* __PERF_EVLIST_H */
--
1.6.2.5

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