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| author | Changbin Du <changbin.du@gmail.com> | 2019-07-30 22:08:50 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-08-06 19:08:15 +0200 |
| commit | e4287f51fcb456f6e4f41a8d41073e63d8ea4fdb (patch) | |
| tree | 26f45dda40ce7338833204f3524c03865b2e6672 /kernel | |
| parent | 349cd3dcbf9b73fcebe9206db124078188d1b9f5 (diff) | |
| download | linux-stable-e4287f51fcb456f6e4f41a8d41073e63d8ea4fdb.tar.gz linux-stable-e4287f51fcb456f6e4f41a8d41073e63d8ea4fdb.tar.bz2 linux-stable-e4287f51fcb456f6e4f41a8d41073e63d8ea4fdb.zip | |
fgraph: Remove redundant ftrace_graph_notrace_addr() test
commit 6c77221df96177da0520847ce91e33f539fb8b2d upstream.
We already have tested it before. The second one should be removed.
With this change, the performance should have little improvement.
Link: http://lkml.kernel.org/r/20190730140850.7927-1-changbin.du@gmail.com
Cc: stable@vger.kernel.org
Fixes: 9cd2992f2d6c ("fgraph: Have set_graph_notrace only affect function_graph tracer")
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/trace_functions_graph.c | 17 |
1 files changed, 7 insertions, 10 deletions
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 69ebf3c2f1b5..78af97163147 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -137,6 +137,13 @@ int trace_graph_entry(struct ftrace_graph_ent *trace) if (trace_recursion_test(TRACE_GRAPH_NOTRACE_BIT)) return 0; + /* + * Do not trace a function if it's filtered by set_graph_notrace. + * Make the index of ret stack negative to indicate that it should + * ignore further functions. But it needs its own ret stack entry + * to recover the original index in order to continue tracing after + * returning from the function. + */ if (ftrace_graph_notrace_addr(trace->func)) { trace_recursion_set(TRACE_GRAPH_NOTRACE_BIT); /* @@ -156,16 +163,6 @@ int trace_graph_entry(struct ftrace_graph_ent *trace) return 0; /* - * Do not trace a function if it's filtered by set_graph_notrace. - * Make the index of ret stack negative to indicate that it should - * ignore further functions. But it needs its own ret stack entry - * to recover the original index in order to continue tracing after - * returning from the function. - */ - if (ftrace_graph_notrace_addr(trace->func)) - return 1; - - /* * Stop here if tracing_threshold is set. We only write function return * events to the ring buffer. */ |