From: Namhyung Kim <namhyung@xxxxxxxxxx>
[ Upstream commit 1746212daeba95e9ae1639227dc0c3591d41deeb ]
In copy_bytes(), it reads the data from the (input) fd and writes it to
the output file. But it does with the read(2) unconditionally which
caused a problem of mixing buffered vs unbuffered I/O together.
You can see the problem when using pipes.
$ perf record -e intel_pt// -o- true | perf inject -b > /dev/null
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
0x45c0 [0x30]: failed to process type: 71
It should use perf_data__read() to honor the 'use_stdio' setting.
Fixes: 601366678c93618f ("perf data: Allow to use stdio functions for pipe mode")
Reviewed-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Reviewed-by: James Clark <james.clark@xxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Leo Yan <leo.yan@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230131023350.1903992-2-namhyung@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/perf/builtin-inject.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c
index e254f18986f7c..e2ce5f294cbd4 100644
--- a/tools/perf/builtin-inject.c
+++ b/tools/perf/builtin-inject.c
@@ -215,14 +215,14 @@ static int perf_event__repipe_event_update(struct perf_tool *tool,
#ifdef HAVE_AUXTRACE_SUPPORT
-static int copy_bytes(struct perf_inject *inject, int fd, off_t size)
+static int copy_bytes(struct perf_inject *inject, struct perf_data *data, off_t size)
{
char buf[4096];
ssize_t ssz;
int ret;
while (size > 0) {
- ssz = read(fd, buf, min(size, (off_t)sizeof(buf)));
+ ssz = perf_data__read(data, buf, min(size, (off_t)sizeof(buf)));
if (ssz < 0)
return -errno;
ret = output_bytes(inject, buf, ssz);
@@ -260,7 +260,7 @@ static s64 perf_event__repipe_auxtrace(struct perf_session *session,
ret = output_bytes(inject, event, event->header.size);
if (ret < 0)
return ret;
- ret = copy_bytes(inject, perf_data__fd(session->data),
+ ret = copy_bytes(inject, session->data,
event->auxtrace.size);
} else {
ret = output_bytes(inject, event,
--
2.39.2
