From 3178f58b989430fd0721df97bf21cf1c0e8cc419 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Tue, 14 Jan 2014 16:37:14 +0100 Subject: [PATCH] perf tools: Do proper comm override error handling The comm overriding API ignores memory allocation failures by silently keeping the previous and out of date comm. As a result, the user may get buggy events without ever being notified about the problem and its source. Lets start to fix this by propagating the error from the API. Not all callers may be doing proper error handling on comm set yet but this is the first step toward it. Signed-off-by: Frederic Weisbecker Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: David Ahern Cc: Ingo Molnar Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1389713836-13375-2-git-send-email-fweisbec@gmail.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/comm.c | 19 ++++++++++--------- tools/perf/util/comm.h | 2 +- tools/perf/util/thread.c | 5 ++++- 3 files changed, 15 insertions(+), 11 deletions(-) diff --git a/tools/perf/util/comm.c b/tools/perf/util/comm.c index 67d1e40..f9e7776 100644 --- a/tools/perf/util/comm.c +++ b/tools/perf/util/comm.c @@ -94,19 +94,20 @@ struct comm *comm__new(const char *str, u64 timestamp) return comm; } -void comm__override(struct comm *comm, const char *str, u64 timestamp) +int comm__override(struct comm *comm, const char *str, u64 timestamp) { - struct comm_str *old = comm->comm_str; + struct comm_str *new, *old = comm->comm_str; - comm->comm_str = comm_str__findnew(str, &comm_str_root); - if (!comm->comm_str) { - comm->comm_str = old; - return; - } + new = comm_str__findnew(str, &comm_str_root); + if (!new) + return -ENOMEM; - comm->start = timestamp; - comm_str__get(comm->comm_str); + comm_str__get(new); comm_str__put(old); + comm->comm_str = new; + comm->start = timestamp; + + return 0; } void comm__free(struct comm *comm) diff --git a/tools/perf/util/comm.h b/tools/perf/util/comm.h index 7a86e56..fac5bd5 100644 --- a/tools/perf/util/comm.h +++ b/tools/perf/util/comm.h @@ -16,6 +16,6 @@ struct comm { void comm__free(struct comm *comm); struct comm *comm__new(const char *str, u64 timestamp); const char *comm__str(const struct comm *comm); -void comm__override(struct comm *comm, const char *str, u64 timestamp); +int comm__override(struct comm *comm, const char *str, u64 timestamp); #endif /* __PERF_COMM_H */ diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index e394861..0358882 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -66,10 +66,13 @@ struct comm *thread__comm(const struct thread *thread) int thread__set_comm(struct thread *thread, const char *str, u64 timestamp) { struct comm *new, *curr = thread__comm(thread); + int err; /* Override latest entry if it had no specific time coverage */ if (!curr->start) { - comm__override(curr, str, timestamp); + err = comm__override(curr, str, timestamp); + if (err) + return err; } else { new = comm__new(str, timestamp); if (!new) -- 2.7.4