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From: Michal Pluta <michalpl2003@gmail.com>
To: acme@kernel.org, namhyung@kernel.org
Cc: "Thomas Gleixner" <tglx@kernel.org>,
	"Ingo Molnar" <mingo@redhat.com>,
	"Peter Zijlstra" <peterz@infradead.org>,
	"Darren Hart" <dvhart@infradead.org>,
	"Davidlohr Bueso" <dave@stgolabs.net>,
	"André Almeida" <andrealmeid@igalia.com>,
	"Mark Rutland" <mark.rutland@arm.com>,
	"Alexander Shishkin" <alexander.shishkin@linux.intel.com>,
	"Jiri Olsa" <jolsa@kernel.org>, "Ian Rogers" <irogers@google.com>,
	"Adrian Hunter" <adrian.hunter@intel.com>,
	"James Clark" <james.clark@linaro.org>,
	"Sebastian Andrzej Siewior" <bigeasy@linutronix.de>,
	linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org
Subject: [PATCH 6/8] perf bench futex: Use a 64-bit operation counter in hash and lock-pi
Date: Sat, 26 Sep 2026 20:04:05 +0100	[thread overview]
Message-ID: <20260926190407.1106421-7-michalpl2003@gmail.com> (raw)
In-Reply-To: <20260926190407.1106421-1-michalpl2003@gmail.com>

The per-thread operation counters in 'futex hash' and 'futex lock-pi'
are unsigned longs, which could overflow on 32-bit systems. Use u64
instead.

Assisted-by: LLM
Signed-off-by: Michal Pluta <michalpl2003@gmail.com>
---
 tools/perf/bench/futex-hash.c    | 6 +++---
 tools/perf/bench/futex-lock-pi.c | 6 +++---
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/tools/perf/bench/futex-hash.c b/tools/perf/bench/futex-hash.c
index 710c253cfe17..e18d98664d27 100644
--- a/tools/perf/bench/futex-hash.c
+++ b/tools/perf/bench/futex-hash.c
@@ -46,7 +46,7 @@ struct worker {
 	int tid;
 	u_int32_t *futex;
 	pthread_t thread;
-	unsigned long ops;
+	u64 ops;
 };
 
 static struct bench_futex_parameters params = {
@@ -76,7 +76,7 @@ static void *workerfn(void *arg)
 	int ret;
 	struct worker *w = (struct worker *) arg;
 	unsigned int i;
-	unsigned long ops = w->ops; /* avoid cacheline bouncing */
+	u64 ops = w->ops; /* avoid cacheline bouncing */
 
 	mutex_lock(&thread_lock);
 	threads_starting--;
@@ -238,7 +238,7 @@ int bench_futex_hash(int argc, const char **argv)
 
 	for (i = 0; i < params.nthreads; i++) {
 		unsigned long t = runtime_us ?
-			(u64)worker[i].ops * USEC_PER_SEC / runtime_us : 0;
+			worker[i].ops * USEC_PER_SEC / runtime_us : 0;
 		update_stats(&throughput_stats, t);
 		if (!params.silent) {
 			if (params.nfutexes == 1)
diff --git a/tools/perf/bench/futex-lock-pi.c b/tools/perf/bench/futex-lock-pi.c
index 7190f5102e09..8016a31b198d 100644
--- a/tools/perf/bench/futex-lock-pi.c
+++ b/tools/perf/bench/futex-lock-pi.c
@@ -29,7 +29,7 @@ struct worker {
 	int tid;
 	u_int32_t *futex;
 	pthread_t thread;
-	unsigned long ops;
+	u64 ops;
 };
 
 static u_int32_t global_futex = 0;
@@ -86,7 +86,7 @@ static void toggle_done(int sig __maybe_unused,
 static void *workerfn(void *arg)
 {
 	struct worker *w = (struct worker *) arg;
-	unsigned long ops = w->ops;
+	u64 ops = w->ops;
 
 	mutex_lock(&thread_lock);
 	threads_starting--;
@@ -239,7 +239,7 @@ int bench_futex_lock_pi(int argc, const char **argv)
 
 	for (i = 0; i < params.nthreads; i++) {
 		unsigned long t = runtime_us ?
-			(u64)worker[i].ops * USEC_PER_SEC / runtime_us : 0;
+			worker[i].ops * USEC_PER_SEC / runtime_us : 0;
 
 		update_stats(&throughput_stats, t);
 		if (!params.silent)
-- 
2.43.0


  parent reply	other threads:[~2026-09-26 19:04 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-09-26 19:03 [PATCH 0/8] perf bench futex: Fix several bugs and bad inputs Michal Pluta
2026-09-26 19:04 ` [PATCH 1/8] perf bench futex: Retry futex_wait() when interrupted by a signal Michal Pluta
2026-09-26 19:04 ` [PATCH 2/8] perf bench futex: Set the number of hash buckets in futex wake Michal Pluta
2026-09-26 19:04 ` [PATCH 3/8] perf bench futex: Use the whole timeval for elapsed times Michal Pluta
2026-09-26 19:04 ` [PATCH 4/8] perf bench futex: Reject invalid -q, -f and -b values Michal Pluta
2026-09-26 19:04 ` [PATCH 5/8] perf bench futex: Stop when futex_wake() fails in futex wake Michal Pluta
2026-09-26 19:04 ` Michal Pluta [this message]
2026-09-26 19:04 ` [PATCH 7/8] perf bench futex: Clean up two nits in futex hash Michal Pluta
2026-09-26 19:04 ` [PATCH 8/8] perf bench futex: Fix wording in futex bench messages Michal Pluta

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