From c3a057dc3aa9979ce6dc350e05eb2e4c021432cd Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Mon, 19 Jul 2021 15:31:52 -0700 Subject: perf inject: Fix output from a file to a pipe When the input is a regular file but the output is a pipe, it should write a pipe header. But just repiping would write a portion of the existing header which is different in 'size' value. So we need to prevent it and write a new pipe header along with other information like event attributes and features. This can handle something like this: # perf record -a -B sleep 1 # perf inject -b -i perf.data | perf report -i - Factor out perf_event__synthesize_for_pipe() to be shared between perf record and inject. Signed-off-by: Namhyung Kim Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Andi Kleen Cc: Ian Rogers Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20210719223153.1618812-5-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/synthetic-events.c | 53 +++++++++++++++++++++++++++++++++++++- 1 file changed, 52 insertions(+), 1 deletion(-) (limited to 'tools/perf/util/synthetic-events.c') diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c index 35aa0c0f7cd9..a7e981b2d7de 100644 --- a/tools/perf/util/synthetic-events.c +++ b/tools/perf/util/synthetic-events.c @@ -1,5 +1,7 @@ // SPDX-License-Identifier: GPL-2.0-only +#include "util/cgroup.h" +#include "util/data.h" #include "util/debug.h" #include "util/dso.h" #include "util/event.h" @@ -16,7 +18,6 @@ #include "util/synthetic-events.h" #include "util/target.h" #include "util/time-utils.h" -#include "util/cgroup.h" #include #include #include @@ -2179,3 +2180,53 @@ int perf_event__synthesize_features(struct perf_tool *tool, struct perf_session free(ff.buf); return ret; } + +int perf_event__synthesize_for_pipe(struct perf_tool *tool, + struct perf_session *session, + struct perf_data *data, + perf_event__handler_t process) +{ + int err; + int ret = 0; + struct evlist *evlist = session->evlist; + + /* + * We need to synthesize events first, because some + * features works on top of them (on report side). + */ + err = perf_event__synthesize_attrs(tool, evlist, process); + if (err < 0) { + pr_err("Couldn't synthesize attrs.\n"); + return err; + } + ret += err; + + err = perf_event__synthesize_features(tool, session, evlist, process); + if (err < 0) { + pr_err("Couldn't synthesize features.\n"); + return err; + } + ret += err; + + if (have_tracepoints(&evlist->core.entries)) { + int fd = perf_data__fd(data); + + /* + * FIXME err <= 0 here actually means that + * there were no tracepoints so its not really + * an error, just that we don't need to + * synthesize anything. We really have to + * return this more properly and also + * propagate errors that now are calling die() + */ + err = perf_event__synthesize_tracing_data(tool, fd, evlist, + process); + if (err <= 0) { + pr_err("Couldn't record tracing data.\n"); + return err; + } + ret += err; + } + + return ret; +} -- cgit v1.2.3