[tip:perfcounters/core] perf_counter: tools: Better handle existing data files

tip-bot for Peter Zijlstra
2009-06-02T14:20:48Z

Commit-ID: 97124d5e2df5b9eaa5bb684bb1e8ebc7e29d0f5d
Gitweb: http://git.kernel.org/tip/97124d5e2df5b9eaa5bb684bb1e8ebc7e29d0f5d
Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
AuthorDate: Tue, 2 Jun 2009 15:52:24 +0200
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Tue, 2 Jun 2009 16:16:26 +0200

perf_counter: tools: Better handle existing data files

Provide an argument (-f) to overwrite existing data files.

Signed-off-by: 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 | 15 ++++++++++++---
1 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/Documentation/perf_counter/builtin-record.c b/Documentation/perf_counter/builtin-record.c
index 810fc27..bace7a8 100644
--- a/Documentation/perf_counter/builtin-record.c
+++ b/Documentation/perf_counter/builtin-record.c
@@ -7,6 +7,7 @@
#include "util/parse-events.h"
#include "util/string.h"

+#include <unistd.h>
#include <sched.h>

#define ALIGN(x, a) __ALIGN_MASK(x, (typeof(x))(a)-1)
@@ -26,7 +27,7 @@ static unsigned int realtime_prio = 0;
static int system_wide = 0;
static pid_t target_pid = -1;
static int inherit = 1;
-static int nmi = 1;
+static int force = 0;

const unsigned int default_count[] = {
1000000,
@@ -337,7 +338,6 @@ static void open_counters(int cpu, pid_t pid)
hw_event.config = event_id[counter];
hw_event.irq_period = event_count[counter];
hw_event.record_type = PERF_RECORD_IP | PERF_RECORD_TID;
- hw_event.nmi = nmi;
hw_event.mmap = track;
hw_event.comm = track;
hw_event.inherit = (cpu < 0) && inherit;
@@ -387,13 +387,20 @@ static int __cmd_record(int argc, const char **argv)
int i, counter;
pid_t pid;
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);

- output = open(output_name, O_CREAT|O_EXCL|O_TRUNC|O_RDWR, S_IRUSR|S_IWUSR);
+ if (!stat(output_name, &st) && !force) {
+ fprintf(stderr, "Error, output file: %s exists, use -f to overwrite.\n",
+ output_name);
+ exit(-1);
+ }
+
+ output = open(output_name, O_CREAT|O_TRUNC|O_RDWR, S_IRUSR|S_IWUSR);
if (output < 0) {
perror("failed to create output file");
exit(-1);
@@ -473,6 +480,8 @@ static const struct option options[] = {
"collect data with this RT SCHED_FIFO priority"),
OPT_BOOLEAN('a', "all-cpus", &system_wide,
"system-wide collection from all CPUs"),
+ OPT_BOOLEAN('f', "force", &force,
+ "overwrite existing data file"),
OPT_END()
};