[PATCH v1 1/2] perf comm str: Avoid sort during insert
From: Ian Rogers
Date: Wed Jul 03 2024 - 13:21:56 EST
The array is sorted, so just move the elements and insert in order.
Reported-by: Matt Fleming <matt@xxxxxxxxxxxxxxxx>
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/comm.c | 29 ++++++++++++++++++-----------
1 file changed, 18 insertions(+), 11 deletions(-)
diff --git a/tools/perf/util/comm.c b/tools/perf/util/comm.c
index 233f2b6edf52..49b79cf0c5cc 100644
--- a/tools/perf/util/comm.c
+++ b/tools/perf/util/comm.c
@@ -86,14 +86,6 @@ static struct comm_str *comm_str__new(const char *str)
return result;
}
-static int comm_str__cmp(const void *_lhs, const void *_rhs)
-{
- const struct comm_str *lhs = *(const struct comm_str * const *)_lhs;
- const struct comm_str *rhs = *(const struct comm_str * const *)_rhs;
-
- return strcmp(comm_str__str(lhs), comm_str__str(rhs));
-}
-
static int comm_str__search(const void *_key, const void *_member)
{
const char *key = _key;
@@ -169,9 +161,24 @@ static struct comm_str *comm_strs__findnew(const char *str)
}
result = comm_str__new(str);
if (result) {
- comm_strs->strs[comm_strs->num_strs++] = result;
- qsort(comm_strs->strs, comm_strs->num_strs, sizeof(struct comm_str *),
- comm_str__cmp);
+ int low = 0, high = comm_strs->num_strs - 1;
+ int insert = comm_strs->num_strs; /* Default to inserting at the end. */
+
+ while (low <= high) {
+ int mid = low + (high - low) / 2;
+ int cmp = strcmp(comm_str__str(comm_strs->strs[mid]), str);
+
+ if (cmp < 0) {
+ low = mid + 1;
+ } else {
+ high = mid - 1;
+ insert = mid;
+ }
+ }
+ memmove(&comm_strs->strs[insert + 1], &comm_strs->strs[insert],
+ (comm_strs->num_strs - insert) * sizeof(struct comm_str *));
+ comm_strs->num_strs++;
+ comm_strs->strs[insert] = result;
}
}
up_write(&comm_strs->lock);
--
2.45.2.803.g4e1b14247a-goog