linux-kernel - [PATCH] perf/core: Replace memset(0) + strscpy() with strscpy

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Message-ID: <20250811091637.4492-2-thorsten.blum@linux.dev>
Date: Mon, 11 Aug 2025 11:16:38 +0200
From: Thorsten Blum <thorsten.blum@...ux.dev>
To: Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...hat.com>,
	Arnaldo Carvalho de Melo <acme@...nel.org>,
	Namhyung Kim <namhyung@...nel.org>,
	Mark Rutland <mark.rutland@....com>,
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
	Jiri Olsa <jolsa@...nel.org>,
	Ian Rogers <irogers@...gle.com>,
	Adrian Hunter <adrian.hunter@...el.com>,
	"Liang, Kan" <kan.liang@...ux.intel.com>
Cc: Thorsten Blum <thorsten.blum@...ux.dev>,
	linux-perf-users@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] perf/core: Replace memset(0) + strscpy() with strscpy_pad()

Replace memset(0) followed by strscpy() with strscpy_pad() to improve
perf_event_comm_event(). This avoids zeroing the memory before copying
the string and ensures the destination buffer is only written to once,
simplifying the code and improving efficiency.

Use the return value of strscpy_pad() instead of calling strlen() again.

Signed-off-by: Thorsten Blum <thorsten.blum@...ux.dev>
---
 kernel/events/core.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 22fdf0c187cd..69b4a32befec 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8961,9 +8961,8 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
 	char comm[TASK_COMM_LEN];
 	unsigned int size;
 
-	memset(comm, 0, sizeof(comm));
-	strscpy(comm, comm_event->task->comm);
-	size = ALIGN(strlen(comm)+1, sizeof(u64));
+	size = strscpy_pad(comm, comm_event->task->comm);
+	size = ALIGN(size + 1, sizeof(u64));
 
 	comm_event->comm = comm;
 	comm_event->comm_size = size;
-- 
2.50.1