[tip:perfcounters/core] perf record: Add --append option

tip-bot for Ingo Molnar
2009-06-02T22:08:01Z

Commit-ID: abaff32a03e26e5d6674cb2a26ad882efe7493a3
Gitweb: http://git.kernel.org/tip/abaff32a03e26e5d6674cb2a26ad882efe7493a3
Author: Ingo Molnar <mingo@elte.hu>
AuthorDate: Tue, 2 Jun 2009 22:59:57 +0200
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Tue, 2 Jun 2009 23:01:02 +0200

perf record: Add --append option

Allow incremental profiling via 'perf record -A' - this will append
to an existing perf.data.

Also reorder perf record options by utility / likelyhood of usage.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

---
Documentation/perf_counter/builtin-record.c | 40 +++++++++++++++++---------
1 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/Documentation/perf_counter/builtin-record.c b/Documentation/perf_counter/builtin-record.c
index c2fd042..19cba6b 100644
--- a/Documentation/perf_counter/builtin-record.c
+++ b/Documentation/perf_counter/builtin-record.c
@@ -1,5 +1,7 @@
-
-
+/*
+ * perf record: Record the profile of a workload (or a CPU, or a PID) into
+ * the perf.data output file - for later analysis via perf report.
+ */
#include "perf.h"
#include "builtin.h"
#include "util/util.h"
@@ -28,6 +30,7 @@ static int system_wide = 0;
static pid_t target_pid = -1;
static int inherit = 1;
static int force = 0;
+static int append_file = 0;

const unsigned int default_count[] = {
1000000,
@@ -385,22 +388,29 @@ static void open_counters(int cpu, pid_t pid)
static int __cmd_record(int argc, const char **argv)
{
int i, counter;
+ struct stat st;
pid_t pid;
+ int flags;
int ret;
- struct stat st;

page_size = sysconf(_SC_PAGE_SIZE);
nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
assert(nr_cpus <= MAX_NR_CPUS);
assert(nr_cpus >= 0);

- if (!stat(output_name, &st) && !force) {
- fprintf(stderr, "Error, output file: %s exists, use -f to overwrite.\n",
+ if (!stat(output_name, &st) && !force && !append_file) {
+ fprintf(stderr, "Error, output file %s exists, use -A to append or -f to overwrite.\n",
output_name);
exit(-1);
}

- output = open(output_name, O_CREAT|O_TRUNC|O_RDWR, S_IRUSR|S_IWUSR);
+ flags = O_CREAT|O_RDWR;
+ if (append_file)
+ flags |= O_APPEND;
+ else
+ flags |= O_TRUNC;
+
+ output = open(output_name, flags, S_IRUSR|S_IWUSR);
if (output < 0) {
perror("failed to create output file");
exit(-1);
@@ -466,22 +476,24 @@ static char events_help_msg[EVENTS_HELP_MAX];
static const struct option options[] = {
OPT_CALLBACK('e', "event", NULL, "event",
events_help_msg, parse_events),
- OPT_INTEGER('c', "count", &default_interval,
- "event period to sample"),
- OPT_INTEGER('m', "mmap-pages", &mmap_pages,
- "number of mmap data pages"),
- OPT_STRING('o', "output", &output_name, "file",
- "output file name"),
- OPT_BOOLEAN('i', "inherit", &inherit,
- "child tasks inherit counters"),
OPT_INTEGER('p', "pid", &target_pid,
"record events on existing pid"),
OPT_INTEGER('r', "realtime", &realtime_prio,
"collect data with this RT SCHED_FIFO priority"),
OPT_BOOLEAN('a', "all-cpus", &system_wide,
"system-wide collection from all CPUs"),
+ OPT_BOOLEAN('A', "append", &append_file,
+ "append to the output file to do incremental profiling"),
OPT_BOOLEAN('f', "force", &force,
"overwrite existing data file"),
+ OPT_INTEGER('c', "count", &default_interval,
+ "event period to sample"),
+ OPT_STRING('o', "output", &output_name, "file",
+ "output file name"),
+ OPT_BOOLEAN('i', "inherit", &inherit,
+ "child tasks inherit counters"),
+ OPT_INTEGER('m', "mmap-pages", &mmap_pages,
+ "number of mmap data pages"),
OPT_END()
};