On Thu, 20 Jul 2023 17:30:42 +0100 Valentin Schneider vschneid@redhat.com wrote:
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.
Suggested-by: Steven Rostedt rostedt@goodmis.org Signed-off-by: Valentin Schneider vschneid@redhat.com
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 2fe65ddeb34ef..54d642fabb7f1 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;
Nit, the above can be written as:
pred->op = pret->op != OP_BAND ? : OP_EQ;
-- Steve
pred->fn_num = select_comparison_fn(pred->op, field->size, false);
if (pred->op == OP_NE)
} else { switch (field->size) { case 8:pred->not = 1;