From: Peter Zijlstra <peterz@infradead.org>
To: mingo@kernel.org, oleg@redhat.com, gkohli@codeaurora.org
Cc: tglx@linutronix.de, mpe@ellerman.id.au, bigeasy@linutronix.de,
linux-kernel@vger.kernel.org, will.deacon@arm.com,
"Peter Zijlstra (Intel)" <peterz@infradead.org>
Subject: [PATCH 3/4] smpboot: Remove cpumask from the API
Date: Thu, 07 Jun 2018 14:33:13 +0200 [thread overview]
Message-ID: <20180607124006.211011673@infradead.org> (raw)
In-Reply-To: 20180607123310.866085998@infradead.org
[-- Attachment #1: peterz-kthread-2.patch --]
[-- Type: text/plain, Size: 5064 bytes --]
Now that the sole use of the whole smpboot_*cpumask() API is gone,
remove it.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
include/linux/smpboot.h | 15 -------------
kernel/smpboot.c | 54 ++++--------------------------------------------
2 files changed, 6 insertions(+), 63 deletions(-)
--- a/include/linux/smpboot.h
+++ b/include/linux/smpboot.h
@@ -25,8 +25,6 @@ struct smpboot_thread_data;
* parked (cpu offline)
* @unpark: Optional unpark function, called when the thread is
* unparked (cpu online)
- * @cpumask: Internal state. To update which threads are unparked,
- * call smpboot_update_cpumask_percpu_thread().
* @selfparking: Thread is not parked by the park function.
* @thread_comm: The base name of the thread
*/
@@ -40,23 +38,12 @@ struct smp_hotplug_thread {
void (*cleanup)(unsigned int cpu, bool online);
void (*park)(unsigned int cpu);
void (*unpark)(unsigned int cpu);
- cpumask_var_t cpumask;
bool selfparking;
const char *thread_comm;
};
-int smpboot_register_percpu_thread_cpumask(struct smp_hotplug_thread *plug_thread,
- const struct cpumask *cpumask);
-
-static inline int
-smpboot_register_percpu_thread(struct smp_hotplug_thread *plug_thread)
-{
- return smpboot_register_percpu_thread_cpumask(plug_thread,
- cpu_possible_mask);
-}
+int smpboot_register_percpu_thread(struct smp_hotplug_thread *plug_thread);
void smpboot_unregister_percpu_thread(struct smp_hotplug_thread *plug_thread);
-void smpboot_update_cpumask_percpu_thread(struct smp_hotplug_thread *plug_thread,
- const struct cpumask *);
#endif
--- a/kernel/smpboot.c
+++ b/kernel/smpboot.c
@@ -238,8 +238,7 @@ int smpboot_unpark_threads(unsigned int
mutex_lock(&smpboot_threads_lock);
list_for_each_entry(cur, &hotplug_threads, list)
- if (cpumask_test_cpu(cpu, cur->cpumask))
- smpboot_unpark_thread(cur, cpu);
+ smpboot_unpark_thread(cur, cpu);
mutex_unlock(&smpboot_threads_lock);
return 0;
}
@@ -280,34 +279,26 @@ static void smpboot_destroy_threads(stru
}
/**
- * smpboot_register_percpu_thread_cpumask - Register a per_cpu thread related
+ * smpboot_register_percpu_thread - Register a per_cpu thread related
* to hotplug
* @plug_thread: Hotplug thread descriptor
- * @cpumask: The cpumask where threads run
*
* Creates and starts the threads on all online cpus.
*/
-int smpboot_register_percpu_thread_cpumask(struct smp_hotplug_thread *plug_thread,
- const struct cpumask *cpumask)
+int smpboot_register_percpu_thread(struct smp_hotplug_thread *plug_thread)
{
unsigned int cpu;
int ret = 0;
- if (!alloc_cpumask_var(&plug_thread->cpumask, GFP_KERNEL))
- return -ENOMEM;
- cpumask_copy(plug_thread->cpumask, cpumask);
-
get_online_cpus();
mutex_lock(&smpboot_threads_lock);
for_each_online_cpu(cpu) {
ret = __smpboot_create_thread(plug_thread, cpu);
if (ret) {
smpboot_destroy_threads(plug_thread);
- free_cpumask_var(plug_thread->cpumask);
goto out;
}
- if (cpumask_test_cpu(cpu, cpumask))
- smpboot_unpark_thread(plug_thread, cpu);
+ smpboot_unpark_thread(plug_thread, cpu);
}
list_add(&plug_thread->list, &hotplug_threads);
out:
@@ -315,7 +306,7 @@ int smpboot_register_percpu_thread_cpuma
put_online_cpus();
return ret;
}
-EXPORT_SYMBOL_GPL(smpboot_register_percpu_thread_cpumask);
+EXPORT_SYMBOL_GPL(smpboot_register_percpu_thread);
/**
* smpboot_unregister_percpu_thread - Unregister a per_cpu thread related to hotplug
@@ -331,44 +322,9 @@ void smpboot_unregister_percpu_thread(st
smpboot_destroy_threads(plug_thread);
mutex_unlock(&smpboot_threads_lock);
put_online_cpus();
- free_cpumask_var(plug_thread->cpumask);
}
EXPORT_SYMBOL_GPL(smpboot_unregister_percpu_thread);
-/**
- * smpboot_update_cpumask_percpu_thread - Adjust which per_cpu hotplug threads stay parked
- * @plug_thread: Hotplug thread descriptor
- * @new: Revised mask to use
- *
- * The cpumask field in the smp_hotplug_thread must not be updated directly
- * by the client, but only by calling this function.
- * This function can only be called on a registered smp_hotplug_thread.
- */
-void smpboot_update_cpumask_percpu_thread(struct smp_hotplug_thread *plug_thread,
- const struct cpumask *new)
-{
- struct cpumask *old = plug_thread->cpumask;
- static struct cpumask tmp;
- unsigned int cpu;
-
- lockdep_assert_cpus_held();
- mutex_lock(&smpboot_threads_lock);
-
- /* Park threads that were exclusively enabled on the old mask. */
- cpumask_andnot(&tmp, old, new);
- for_each_cpu_and(cpu, &tmp, cpu_online_mask)
- smpboot_park_thread(plug_thread, cpu);
-
- /* Unpark threads that are exclusively enabled on the new mask. */
- cpumask_andnot(&tmp, new, old);
- for_each_cpu_and(cpu, &tmp, cpu_online_mask)
- smpboot_unpark_thread(plug_thread, cpu);
-
- cpumask_copy(old, new);
-
- mutex_unlock(&smpboot_threads_lock);
-}
-
static DEFINE_PER_CPU(atomic_t, cpu_hotplug_state) = ATOMIC_INIT(CPU_POST_DEAD);
/*
next prev parent reply other threads:[~2018-06-07 12:42 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-07 12:33 [PATCH 0/4] kthread/smpboot: More fixes Peter Zijlstra
2018-06-07 12:33 ` [PATCH 1/4] kthread, sched: Fix kthread_parkme() (again...) Peter Zijlstra
2018-06-07 12:33 ` [PATCH 2/4] watchdog/softlockup: Replace "watchdog/%u" threads with cpu_stop_work Peter Zijlstra
2018-06-07 14:24 ` Peter Zijlstra
2018-06-07 14:42 ` Peter Zijlstra
2018-06-08 13:57 ` Oleg Nesterov
2018-06-12 12:17 ` Peter Zijlstra
2018-06-07 12:33 ` Peter Zijlstra [this message]
2018-06-07 12:33 ` [PATCH 4/4] kthread: Simplify kthread_park() completion Peter Zijlstra
2018-06-08 9:52 ` Oleg Nesterov
2018-06-12 12:42 ` Peter Zijlstra
2018-06-25 7:12 ` Peter Zijlstra
2018-06-25 16:53 ` Oleg Nesterov
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