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| author | Thomas Gleixner <tglx@linutronix.de> | 2017-10-03 16:37:53 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2017-10-04 10:53:54 +0200 |
| commit | e31d6883f21c1cdfe5bc64e28411f8a92b783fde (patch) | |
| tree | b027de413e024bea4f8e88d364b7413bc20ac9b3 /kernel/smpboot.c | |
| parent | 6b9dc4806b28214a4a260517e59439e0ac12a15e (diff) | |
| download | linux-e31d6883f21c1cdfe5bc64e28411f8a92b783fde.tar.gz linux-e31d6883f21c1cdfe5bc64e28411f8a92b783fde.tar.bz2 linux-e31d6883f21c1cdfe5bc64e28411f8a92b783fde.zip | |
watchdog/core, powerpc: Lock cpus across reconfiguration
Instead of dropping the cpu hotplug lock after stopping NMI watchdog and
threads and reaquiring for restart, the code and the protection rules
become more obvious when holding cpu hotplug lock across the full
reconfiguration.
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1710022105570.2114@nanos
Diffstat (limited to 'kernel/smpboot.c')
| -rw-r--r-- | kernel/smpboot.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/kernel/smpboot.c b/kernel/smpboot.c index ed7507b69b48..5043e7433f4b 100644 --- a/kernel/smpboot.c +++ b/kernel/smpboot.c @@ -351,7 +351,7 @@ void smpboot_update_cpumask_percpu_thread(struct smp_hotplug_thread *plug_thread static struct cpumask tmp; unsigned int cpu; - get_online_cpus(); + lockdep_assert_cpus_held(); mutex_lock(&smpboot_threads_lock); /* Park threads that were exclusively enabled on the old mask. */ @@ -367,7 +367,6 @@ void smpboot_update_cpumask_percpu_thread(struct smp_hotplug_thread *plug_thread cpumask_copy(old, new); mutex_unlock(&smpboot_threads_lock); - put_online_cpus(); } static DEFINE_PER_CPU(atomic_t, cpu_hotplug_state) = ATOMIC_INIT(CPU_POST_DEAD); |