From: Namhyung Kim namhyung@kernel.org
[ 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@intel.com Reviewed-by: James Clark james.clark@arm.com Signed-off-by: Namhyung Kim namhyung@kernel.org Cc: Ian Rogers irogers@google.com Cc: Ingo Molnar mingo@kernel.org Cc: Jiri Olsa jolsa@kernel.org Cc: Leo Yan leo.yan@linaro.org Cc: Namhyung Kim namhyung@kernel.org Cc: Peter Zijlstra peterz@infradead.org Cc: Stephane Eranian eranian@google.com Link: https://lore.kernel.org/r/20230131023350.1903992-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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,