From ca77dd8ce4658d1006d747dd1995ebb9375199c8 Mon Sep 17 00:00:00 2001 From: Valentin Schneider Date: Fri, 7 Jul 2023 18:21:52 +0100 Subject: tracing/filters: Optimise scalar vs cpumask filtering when the user mask is a single CPU Steven noted that when the user-provided cpumask contains a single CPU, then the filtering function can use a scalar as input instead of a full-fledged cpumask. When the mask contains a single CPU, directly re-use the unsigned field predicate functions. Transform '&' into '==' beforehand. Link: https://lkml.kernel.org/r/20230707172155.70873-7-vschneid@redhat.com Cc: Masami Hiramatsu Cc: Jonathan Corbet Cc: Juri Lelli Cc: Daniel Bristot de Oliveira Cc: Marcelo Tosatti Cc: Leonardo Bras Cc: Frederic Weisbecker Suggested-by: Steven Rostedt Signed-off-by: Valentin Schneider Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_events_filter.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 2fe65ddeb34e..54d642fabb7f 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -1750,7 +1750,7 @@ static int parse_pred(const char *str, void *data, * then we can treat it as a scalar input. */ single = cpumask_weight(pred->mask) == 1; - if (single && field->filter_type == FILTER_CPUMASK) { + if (single && field->filter_type != FILTER_CPU) { pred->val = cpumask_first(pred->mask); kfree(pred->mask); } @@ -1761,6 +1761,11 @@ static int parse_pred(const char *str, void *data, FILTER_PRED_FN_CPUMASK; } else if (field->filter_type == FILTER_CPU) { pred->fn_num = FILTER_PRED_FN_CPU_CPUMASK; + } else if (single) { + pred->op = pred->op == OP_BAND ? OP_EQ : pred->op; + pred->fn_num = select_comparison_fn(pred->op, field->size, false); + if (pred->op == OP_NE) + pred->not = 1; } else { switch (field->size) { case 8: -- cgit