If the filesystem where a file is written using mmap fills perf record
gets a SIGBUS and terminated. Handle the SIGBUS by using longjmp to
bounce out of the memcpy and fail the write.
Signed-off-by: David Ahern <dsah...@gmail.com>
Cc: Ingo Molnar <mi...@kernel.org>
Cc: Frederic Weisbecker <fweis...@gmail.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Jiri Olsa <jo...@redhat.com>
Cc: Namhyung Kim <namhy...@kernel.org>
Cc: Mike Galbraith <efa...@gmx.de>
Cc: Stephane Eranian <eran...@google.com>
---
tools/perf/builtin-record.c | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 1a4fa5df215b..48d6535d144f 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -29,9 +29,11 @@
#include <unistd.h>
#include <sched.h>
#include <sys/mman.h>
+#include <setjmp.h>
/* output file mmap'ed N chunks at a time */
#define MMAP_OUTPUT_SIZE (64*1024*1024)
+sigjmp_buf mmap_jmp;
#ifndef HAVE_ON_EXIT_SUPPORT
#ifndef ATEXIT_MAX
@@ -141,6 +143,7 @@ static int do_mmap_output(struct perf_record *rec, void
*buf, size_t size)
{
u64 remaining;
off_t offset;
+ volatile size_t total_len = 0;
if (rec->mmap.addr == NULL) {
next_segment:
@@ -157,20 +160,23 @@ next_segment:
* space write what we can then go back and create the
* next segment
*/
- if (size > remaining) {
- memcpy(rec->mmap.addr + rec->mmap.offset, buf, remaining);
+ if (setjmp(mmap_jmp) != 0) {
+ pr_err("mmap copy failed.\n");
+ return -1;
+ }
+ if (size-total_len > remaining) {
+ memcpy(rec->mmap.addr + rec->mmap.offset, buf+total_len,
remaining);
rec->bytes_written += remaining;
- size -= remaining;
- buf += remaining;
+ total_len += remaining;
munmap(rec->mmap.addr, rec->mmap.out_size);
goto next_segment;
}
/* more data to copy and it fits in the current segment */
- if (size) {
- memcpy(rec->mmap.addr + rec->mmap.offset, buf, size);
+ if (size - total_len) {
+ memcpy(rec->mmap.addr + rec->mmap.offset, buf+total_len,
size-total_len);
rec->bytes_written += size;
rec->mmap.offset += size;
}
@@ -272,6 +278,9 @@ static void sig_handler(int sig)
if (sig == SIGCHLD)
child_finished = 1;
+ if (sig == SIGBUS)
+ longjmp(mmap_jmp, 1);
+
done = 1;
signr = sig;
}
@@ -532,6 +541,7 @@ static int __cmd_record(struct perf_record *rec, int argc,
const char **argv)
signal(SIGINT, sig_handler);
signal(SIGUSR1, sig_handler);
signal(SIGTERM, sig_handler);
+ signal(SIGBUS, sig_handler);
session = perf_session__new(file, false, NULL);
if (session == NULL) {
--
1.8.3.4 (Apple Git-47)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
