Building the Linux kernel with Clang and LLVM
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From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@kernel.org>,
	linux-kernel@vger.kernel.org, llvm@lists.linux.dev
Cc: Ingo Molnar <mingo@redhat.com>,
	Juri Lelli <juri.lelli@redhat.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Dietmar Eggemann <dietmar.eggemann@arm.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
	Valentin Schneider <vschneid@redhat.com>,
	Nathan Chancellor <nathan@kernel.org>,
	Nick Desaulniers <nick.desaulniers+lkml@gmail.com>,
	Bill Wendling <morbo@google.com>,
	Justin Stitt <justinstitt@google.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Subject: [PATCH v1 1/1] sched: Remove never used code in mm_cid_get()
Date: Wed, 15 Oct 2025 11:19:34 +0200	[thread overview]
Message-ID: <20251015091935.2977229-1-andriy.shevchenko@linux.intel.com> (raw)

Clang is not happy with set but unused variable (this is visible
with `make W=1` build:

kernel/sched/sched.h:3744:18: error: variable 'cpumask' set but not used [-Werror,-Wunused-but-set-variable]

It seems like the variable was never be used along with the assignment that
does not have side effects as far as I can see. Remove those altogether.

Fixes: 223baf9d17f2 ("sched: Fix performance regression introduced by mm_cid")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 kernel/sched/sched.h | 2 --
 1 file changed, 2 deletions(-)

diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 1f5d07067f60..361f9101cef9 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -3740,11 +3740,9 @@ static inline int mm_cid_get(struct rq *rq, struct task_struct *t,
 			     struct mm_struct *mm)
 {
 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
-	struct cpumask *cpumask;
 	int cid;
 
 	lockdep_assert_rq_held(rq);
-	cpumask = mm_cidmask(mm);
 	cid = __this_cpu_read(pcpu_cid->cid);
 	if (mm_cid_is_valid(cid)) {
 		mm_cid_snapshot_time(rq, mm);
-- 
2.50.1


             reply	other threads:[~2025-10-15  9:20 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-10-15  9:19 Andy Shevchenko [this message]
2025-10-20 10:10 ` [PATCH v1 1/1] sched: Remove never used code in mm_cid_get() Andy Shevchenko
2025-10-20 10:49   ` Peter Zijlstra
2025-10-22 16:46     ` Andy Shevchenko
2025-10-24 21:19     ` Eric Biggers
2025-10-24 23:56       ` Linus Torvalds

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