From faa5c5c36ec50bf43e39c7798ce9701e6b002db3 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Fri, 19 Feb 2010 23:02:07 -0200 Subject: [PATCH] perf tools: Don't use parent comm if not set at fork time MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit As the parent comm then is worthless, confusing users about the thread where the sample really happened, leading to think that the sample happened in the parent, not where it really happened, in the children of a thread for which a PERF_RECORD_COMM event was not received. Signed-off-by: Arnaldo Carvalho de Melo Cc: Frédéric Weisbecker Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Paul Mackerras LKML-Reference: <1266627727-19715-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar --- tools/perf/util/thread.c | 18 ++++++++++++------ tools/perf/util/thread.h | 1 + 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index 634b7f7140d5..9e8995eaf2b6 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -36,7 +36,10 @@ int thread__set_comm(struct thread *self, const char *comm) if (self->comm) free(self->comm); self->comm = strdup(comm); - return self->comm ? 0 : -ENOMEM; + if (self->comm == NULL) + return -ENOMEM; + self->comm_set = true; + return 0; } int thread__comm_len(struct thread *self) @@ -255,11 +258,14 @@ int thread__fork(struct thread *self, struct thread *parent) { int i; - if (self->comm) - free(self->comm); - self->comm = strdup(parent->comm); - if (!self->comm) - return -ENOMEM; + if (parent->comm_set) { + if (self->comm) + free(self->comm); + self->comm = strdup(parent->comm); + if (!self->comm) + return -ENOMEM; + self->comm_set = true; + } for (i = 0; i < MAP__NR_TYPES; ++i) if (map_groups__clone(&self->mg, &parent->mg, i) < 0) diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h index 56f317b8a06c..0a28f39de545 100644 --- a/tools/perf/util/thread.h +++ b/tools/perf/util/thread.h @@ -15,6 +15,7 @@ struct thread { struct map_groups mg; pid_t pid; char shortname[3]; + bool comm_set; char *comm; int comm_len; }; -- 2.20.1