[tip:perfcounters/core] perf record: Split out counter creation into a helper function

tip-bot for Ingo Molnar
2009-06-05T12:46:25Z

Commit-ID: f250c030a87273f8838a2302bee7c2b4d03e9151
Gitweb: http://git.kernel.org/tip/f250c030a87273f8838a2302bee7c2b4d03e9151
Author: Ingo Molnar <mingo@elte.hu>
AuthorDate: Fri, 5 Jun 2009 13:18:41 +0200
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Fri, 5 Jun 2009 13:29:57 +0200

perf record: Split out counter creation into a helper function

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

---
Documentation/perf_counter/builtin-record.c | 100 ++++++++++++++-------------
1 files changed, 53 insertions(+), 47 deletions(-)

diff --git a/Documentation/perf_counter/builtin-record.c b/Documentation/perf_counter/builtin-record.c
index bf59df5..7f2d7ce 100644
--- a/Documentation/perf_counter/builtin-record.c
+++ b/Documentation/perf_counter/builtin-record.c
@@ -336,65 +336,71 @@ static void synthesize_events(void)
closedir(proc);
}

-static void open_counters(int cpu, pid_t pid)
+static int group_fd;
+
+static void create_counter(int counter, int cpu, pid_t pid)
{
struct perf_counter_attr attr;
- int counter, group_fd;
int track = 1;

- if (pid > 0) {
- pid_synthesize_comm_event(pid, 0);
- pid_synthesize_mmap_events(pid);
- }
+ memset(&attr, 0, sizeof(attr));
+ attr.config = event_id[counter];
+ attr.sample_period = event_count[counter];
+ attr.sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
+ attr.mmap = track;
+ attr.comm = track;
+ attr.inherit = (cpu < 0) && inherit;

- group_fd = -1;
- for (counter = 0; counter < nr_counters; counter++) {
+ track = 0; /* only the first counter needs these */

- memset(&attr, 0, sizeof(attr));
- attr.config = event_id[counter];
- attr.sample_period = event_count[counter];
- attr.sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
- attr.mmap = track;
- attr.comm = track;
- attr.inherit = (cpu < 0) && inherit;
+ fd[nr_cpu][counter] = sys_perf_counter_open(&attr, pid, cpu, group_fd, 0);

- track = 0; // only the first counter needs these
+ if (fd[nr_cpu][counter] < 0) {
+ int err = errno;

- fd[nr_cpu][counter] =
- sys_perf_counter_open(&attr, pid, cpu, group_fd, 0);
+ error("syscall returned with %d (%s)\n",
+ fd[nr_cpu][counter], strerror(err));
+ if (err == EPERM)
+ printf("Are you root?\n");
+ exit(-1);
+ }
+ assert(fd[nr_cpu][counter] >= 0);
+ fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK);

- if (fd[nr_cpu][counter] < 0) {
- int err = errno;
+ /*
+ * First counter acts as the group leader:
+ */
+ if (group && group_fd == -1)
+ group_fd = fd[nr_cpu][counter];
+
+ 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, 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);
+ }
+}

- error("syscall returned with %d (%s)\n",
- fd[nr_cpu][counter], strerror(err));
- if (err == EPERM)
- printf("Are you root?\n");
- exit(-1);
- }
- assert(fd[nr_cpu][counter] >= 0);
- fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK);
+static void open_counters(int cpu, pid_t pid)
+{
+ int counter;

- /*
- * First counter acts as the group leader:
- */
- if (group && group_fd == -1)
- group_fd = fd[nr_cpu][counter];
-
- 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, 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);
- }
+ if (pid > 0) {
+ pid_synthesize_comm_event(pid, 0);
+ pid_synthesize_mmap_events(pid);
}
+
+ group_fd = -1;
+ for (counter = 0; counter < nr_counters; counter++)
+ create_counter(counter, cpu, pid);
+
nr_cpu++;
}