[PATCH RESEND 0/2] clocksource: Use better cpumask API where appropriate

[PATCH RESEND 0/2] clocksource: Use better cpumask API where appropriate

[Yury Norov]

From: Yury Norov [NVIDIA] <yury.norov@gmail.com>

The dedicated API works better and improves on readability

Resend: drop 'fix opencoded...' wording (Tomas)
v2: https://lore.kernel.org/all/20250607141106.563924-1-yury.norov@gmail.com/
v1: https://lore.kernel.org/all/20250604232550.40491-1-yury.norov@gmail.com/

Yury Norov [NVIDIA] (2):
  clocksource: Use cpumask_any_but() in clocksource_verify_choose_cpus()
  clocksource: Use cpumask_next_wrap() in clocksource_watchdog()

 kernel/time/clocksource.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

-- 
2.43.0

[PATCH 1/2] clocksource: Use cpumask_any_but() in clocksource_verify_choose_cpus()

[Yury Norov]

From: "Yury Norov [NVIDIA]" <yury.norov@gmail.com>

cpumask_any_but() is more verbose than cpumask_first() followed by
cpumask_next(). Use it in clocksource_verify_choose_cpus().

Acked-by: John Stultz <jstultz@google.com>
Signed-off-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>
---
 kernel/time/clocksource.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 6a8bc7da9062..a2f2e9f4d37b 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -323,9 +323,7 @@ static void clocksource_verify_choose_cpus(void)
 		return;
 
 	/* Make sure to select at least one CPU other than the current CPU. */
-	cpu = cpumask_first(cpu_online_mask);
-	if (cpu == smp_processor_id())
-		cpu = cpumask_next(cpu, cpu_online_mask);
+	cpu = cpumask_any_but(cpu_online_mask, smp_processor_id());
 	if (WARN_ON_ONCE(cpu >= nr_cpu_ids))
 		return;
 	cpumask_set_cpu(cpu, &cpus_chosen);
-- 
2.43.0

[PATCH 2/2] clocksource: Use cpumask_next_wrap() in clocksource_watchdog()

[Yury Norov]

From: "Yury Norov [NVIDIA]" <yury.norov@gmail.com>

cpumask_next_wrap() is more verbose and efficient comparing to
cpumask_next() followed by cpumask_first().

Acked-by: John Stultz <jstultz@google.com>
Signed-off-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>
---
 kernel/time/clocksource.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index a2f2e9f4d37b..e400fe150f9d 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -587,9 +587,7 @@ static void clocksource_watchdog(struct timer_list *unused)
 	 * Cycle through CPUs to check if the CPUs stay synchronized
 	 * to each other.
 	 */
-	next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
-	if (next_cpu >= nr_cpu_ids)
-		next_cpu = cpumask_first(cpu_online_mask);
+	next_cpu = cpumask_next_wrap(raw_smp_processor_id(), cpu_online_mask);
 
 	/*
 	 * Arm timer if not already pending: could race with concurrent
-- 
2.43.0

Re: [PATCH RESEND 0/2] clocksource: Use better cpumask API where appropriate

[Thomas Gleixner]

On Sat, Jun 14 2025 at 11:50, Yury Norov wrote:
> From: Yury Norov [NVIDIA] <yury.norov@gmail.com>
>
> The dedicated API works better and improves on readability
>
> Resend: drop 'fix opencoded...' wording (Tomas)

This is not a resend as you changed the change log, so it's V3.

Resend is only for unmodified versions where you got no feedback and did
not change anything.

And in the RESEND case you have to keep the version number so stuff can
be identified as resend of a particular version.

People have scripts which depend on submitters following the
rules. Chasing stuff by hand is just waste of time.

Thanks,

        tglx

[tip: timers/core] clocksource: Use cpumask_next_wrap() in clocksource_watchdog()

[tip-bot2 for Yury Norov [NVIDIA]]

The following commit has been merged into the timers/core branch of tip:

Commit-ID:     bfa788dc2ddaea7d7930f63a5c7c8f3668a3f2c5
Gitweb:        https://git.kernel.org/tip/bfa788dc2ddaea7d7930f63a5c7c8f3668a3f2c5
Author:        Yury Norov [NVIDIA] <yury.norov@gmail.com>
AuthorDate:    Sat, 14 Jun 2025 11:50:30 -04:00
Committer:     Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Sat, 14 Jun 2025 20:09:44 +02:00

clocksource: Use cpumask_next_wrap() in clocksource_watchdog()

cpumask_next_wrap() is more verbose and efficient comparing to
cpumask_next() followed by cpumask_first().

Signed-off-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <jstultz@google.com>
Link: https://lore.kernel.org/all/20250614155031.340988-3-yury.norov@gmail.com

---
 kernel/time/clocksource.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index a2f2e9f..e400fe1 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -587,9 +587,7 @@ static void clocksource_watchdog(struct timer_list *unused)
 	 * Cycle through CPUs to check if the CPUs stay synchronized
 	 * to each other.
 	 */
-	next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
-	if (next_cpu >= nr_cpu_ids)
-		next_cpu = cpumask_first(cpu_online_mask);
+	next_cpu = cpumask_next_wrap(raw_smp_processor_id(), cpu_online_mask);
 
 	/*
 	 * Arm timer if not already pending: could race with concurrent

[tip: timers/core] clocksource: Use cpumask_any_but() in clocksource_verify_choose_cpus()

[tip-bot2 for Yury Norov [NVIDIA]]

The following commit has been merged into the timers/core branch of tip:

Commit-ID:     4fa7d61d5a02ad57a05c69365db293afddf678fc
Gitweb:        https://git.kernel.org/tip/4fa7d61d5a02ad57a05c69365db293afddf678fc
Author:        Yury Norov [NVIDIA] <yury.norov@gmail.com>
AuthorDate:    Sat, 14 Jun 2025 11:50:29 -04:00
Committer:     Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Sat, 14 Jun 2025 20:09:44 +02:00

clocksource: Use cpumask_any_but() in clocksource_verify_choose_cpus()

cpumask_any_but() is more verbose than cpumask_first() followed by
cpumask_next(). Use it in clocksource_verify_choose_cpus().

Signed-off-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <jstultz@google.com>
Link: https://lore.kernel.org/all/20250614155031.340988-2-yury.norov@gmail.com

---
 kernel/time/clocksource.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 6a8bc7d..a2f2e9f 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -323,9 +323,7 @@ static void clocksource_verify_choose_cpus(void)
 		return;
 
 	/* Make sure to select at least one CPU other than the current CPU. */
-	cpu = cpumask_first(cpu_online_mask);
-	if (cpu == smp_processor_id())
-		cpu = cpumask_next(cpu, cpu_online_mask);
+	cpu = cpumask_any_but(cpu_online_mask, smp_processor_id());
 	if (WARN_ON_ONCE(cpu >= nr_cpu_ids))
 		return;
 	cpumask_set_cpu(cpu, &cpus_chosen);