Commit 3178f58b authored by Frederic Weisbecker's avatar Frederic Weisbecker Committed by Arnaldo Carvalho de Melo
Browse files

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keeping the previous and out of date comm.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: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Acked-by: default avatarNamhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1389713836-13375-2-git-send-email-fweisbec@gmail.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 99ca4233

tools/perf/util/comm.c

+10 −9
Original line number Diff line number Diff line
@@ -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)

tools/perf/util/comm.h

+1 −1
Original line number Diff line number Diff line
@@ -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 */

tools/perf/util/thread.c

+4 −1
Original line number Diff line number Diff line
@@ -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)

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