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| author | Valentin Schneider <vschneid@redhat.com> | 2023-07-07 19:21:54 +0200 |
|---|---|---|
| committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2023-08-22 11:13:29 +0200 |
| commit | 38c6f68083895e5e732239dbb277e87fa76f5cd3 (patch) | |
| tree | aaf2b52f7b12dceb587b156ac94c50600219b628 /kernel/trace | |
| parent | tracing/filters: Optimise CPU vs cpumask filtering when the user mask is a si... (diff) | |
| download | linux-38c6f68083895e5e732239dbb277e87fa76f5cd3.tar.xz linux-38c6f68083895e5e732239dbb277e87fa76f5cd3.zip | |
tracing/filters: Further optimise scalar vs cpumask comparison
Per the previous commits, we now only enter do_filter_scalar_cpumask() with
a mask of weight greater than one. Optimise the equality checks.
Link: https://lkml.kernel.org/r/20230707172155.70873-9-vschneid@redhat.com
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Leonardo Bras <leobras@redhat.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Valentin Schneider <vschneid@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace_events_filter.c | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index fd72dacc5d1b..3a529214a21b 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -668,6 +668,25 @@ do_filter_cpumask(int op, const struct cpumask *mask, const struct cpumask *cmp) static inline int do_filter_scalar_cpumask(int op, unsigned int cpu, const struct cpumask *mask) { + /* + * Per the weight-of-one cpumask optimisations, the mask passed in this + * function has a weight >= 2, so it is never equal to a single scalar. + */ + switch (op) { + case OP_EQ: + return false; + case OP_NE: + return true; + case OP_BAND: + return cpumask_test_cpu(cpu, mask); + default: + return 0; + } +} + +static inline int +do_filter_cpumask_scalar(int op, const struct cpumask *mask, unsigned int cpu) +{ switch (op) { case OP_EQ: return cpumask_test_cpu(cpu, mask) && @@ -966,12 +985,7 @@ static int filter_pred_cpumask_cpu(struct filter_pred *pred, void *event) const struct cpumask *mask = (event + loc); unsigned int cpu = pred->val; - /* - * This inverts the usual usage of the function (field is first element, - * user parameter is second), but that's fine because the (scalar, mask) - * operations used are symmetric. - */ - return do_filter_scalar_cpumask(pred->op, cpu, mask); + return do_filter_cpumask_scalar(pred->op, mask, cpu); } /* Filter predicate for COMM. */ |