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From: Shrikanth Hegde <sshegde@linux.ibm.com>
To: mingo@kernel.org, peterz@infradead.org,
	vincent.guittot@linaro.org, linux-kernel@vger.kernel.org
Cc: sshegde@linux.ibm.com, kprateek.nayak@amd.com,
	juri.lelli@redhat.com, vschneid@redhat.com,
	dietmar.eggemann@arm.com, tj@kernel.org, rostedt@goodmis.org,
	mgorman@suse.de, bsegall@google.com, arighi@nvidia.com,
	pauld@redhat.com
Subject: [PATCH v3 4/4] sched: Unify SMT active check via sched_smt_active()
Date: Wed, 13 May 2026 19:09:34 +0530	[thread overview]
Message-ID: <20260513133934.380347-5-sshegde@linux.ibm.com> (raw)
In-Reply-To: <20260513133934.380347-1-sshegde@linux.ibm.com>

There is a use of sched_smt_active() and explicit use of sched_smt_present.
Remove the explicit usage for better code maintenance and readability.

Note that this differs slightly for update_idle_core. It used to call
static_branch_unlikely earlier and now it will call static_branch_likely.

Signed-off-by: Shrikanth Hegde <sshegde@linux.ibm.com>
---
 kernel/sched/core_sched.c | 2 +-
 kernel/sched/fair.c       | 2 +-
 kernel/sched/sched.h      | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/sched/core_sched.c b/kernel/sched/core_sched.c
index 73b6b2426911..43e0bde3038e 100644
--- a/kernel/sched/core_sched.c
+++ b/kernel/sched/core_sched.c
@@ -136,7 +136,7 @@ int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type,
 	struct pid *grp;
 	int err = 0;
 
-	if (!static_branch_likely(&sched_smt_present))
+	if (!sched_smt_active())
 		return -ENODEV;
 
 	BUILD_BUG_ON(PR_SCHED_CORE_SCOPE_THREAD != PIDTYPE_PID);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 964014a74cf9..29fbb5287cfc 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2276,7 +2276,7 @@ numa_type numa_classify(unsigned int imbalance_pct,
 static inline bool test_idle_cores(int cpu);
 static inline int numa_idle_core(int idle_core, int cpu)
 {
-	if (!static_branch_likely(&sched_smt_present) ||
+	if (!sched_smt_active() ||
 	    idle_core >= 0 || !test_idle_cores(cpu))
 		return idle_core;
 
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index e476623a0c2a..ffe77b2b6296 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1671,7 +1671,7 @@ extern void __update_idle_core(struct rq *rq);
 
 static inline void update_idle_core(struct rq *rq)
 {
-	if (static_branch_unlikely(&sched_smt_present))
+	if (sched_smt_active())
 		__update_idle_core(rq);
 }
 
-- 
2.47.3


      parent reply	other threads:[~2026-05-13 13:40 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-05-13 13:39 [PATCH v3 0/4] sched: Simplify CONFIG_SCHED_SMT ifdef usage Shrikanth Hegde
2026-05-13 13:39 ` [PATCH v3 1/4] topology: Introduce cpu_smt_mask for CONFIG_SCHED_SMT=n Shrikanth Hegde
2026-05-13 13:39 ` [PATCH v3 2/4] sched: Simplify ifdeffery around cpu_smt_mask Shrikanth Hegde
2026-05-13 13:39 ` [PATCH v3 3/4] sched/fair: Add sched_smt_active check for fastpaths Shrikanth Hegde
2026-05-13 13:39 ` Shrikanth Hegde [this message]

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