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| author | Steven Rostedt <srostedt@redhat.com> | 2011-01-27 23:12:05 -0500 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2011-02-07 20:56:19 -0500 |
| commit | 55719274188f13cff9e3bd11fdd4c0e7617cd03d (patch) | |
| tree | e9291f7b720e9a1723f94b69ec381360ca275ce2 /kernel | |
| parent | 61e9dea20e1ada886cc49a9ec6fe3c6ac0de7324 (diff) | |
| download | linux-stable-55719274188f13cff9e3bd11fdd4c0e7617cd03d.tar.gz linux-stable-55719274188f13cff9e3bd11fdd4c0e7617cd03d.tar.bz2 linux-stable-55719274188f13cff9e3bd11fdd4c0e7617cd03d.zip | |
tracing/filter: Optimize short ciruit check
The test if we should break out early for OR and AND operations
can be optimized by comparing the current result with
(pred->op == OP_OR)
That is if the result is true and the op is an OP_OR, or
if the result is false and the op is not an OP_OR (thus an OP_AND)
we can break out early in either case. Otherwise we continue
processing.
Cc: Tom Zanussi <tzanussi@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/trace_events_filter.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 10390491b6d0..0a3e0502b507 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -426,9 +426,15 @@ int filter_match_preds(struct event_filter *filter, void *rec) pred->parent, &move); continue; case MOVE_UP_FROM_LEFT: - /* Check for short circuits */ - if ((match && pred->op == OP_OR) || - (!match && pred->op == OP_AND)) { + /* + * Check for short circuits. + * + * Optimization: !!match == (pred->op == OP_OR) + * is the same as: + * if ((match && pred->op == OP_OR) || + * (!match && pred->op == OP_AND)) + */ + if (!!match == (pred->op == OP_OR)) { if (pred == root) break; pred = get_pred_parent(pred, preds, |