From 37ed2cddcbf1b52b03b9b2344c752ed867fa3539 Mon Sep 17 00:00:00 2001 From: Raul Silvera Date: Tue, 21 Jun 2022 15:27:25 +0000 Subject: perf inject: Adjust output data offset for backward compatibility When 'perf inject' creates a new file, it reuses the data offset from the input file. If there has been a change on the size of the header, as happened in v5.12 -> v5.13, the new offsets will be wrong, resulting in a corrupted output file. This change adds the function perf_session__data_offset to compute the data offset based on the current header size, and uses that instead of the offset from the original input file. Signed-off-by: Raul Silvera Acked-by: Adrian Hunter Cc: Alexander Shishkin Cc: Athira Jajeev Cc: Colin Ian King Cc: Dave Marchevsky Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20220621152725.2668041-1-rsilvera@google.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/header.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'tools/perf/util/header.c') diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c index 53332da100e8..6ad629db63b7 100644 --- a/tools/perf/util/header.c +++ b/tools/perf/util/header.c @@ -3686,6 +3686,20 @@ int perf_session__write_header(struct perf_session *session, return perf_session__do_write_header(session, evlist, fd, at_exit, NULL); } +size_t perf_session__data_offset(const struct evlist *evlist) +{ + struct evsel *evsel; + size_t data_offset; + + data_offset = sizeof(struct perf_file_header); + evlist__for_each_entry(evlist, evsel) { + data_offset += evsel->core.ids * sizeof(u64); + } + data_offset += evlist->core.nr_entries * sizeof(struct perf_file_attr); + + return data_offset; +} + int perf_session__inject_header(struct perf_session *session, struct evlist *evlist, int fd, -- cgit v1.2.3-59-g8ed1b