| Date | Thu, 20 Apr 2017 04:23:27 -0700 | From | tip-bot for Sebastian Andrzej Siewior <> | Subject | [tip:smp/hotplug] perf/x86/intel/cqm: Use cpuhp_setup_state_cpuslocked() |
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Commit-ID: 88840592a3483951be52f3ed35f4c4348dc9eed9 Gitweb: http://git.kernel.org/tip/88840592a3483951be52f3ed35f4c4348dc9eed9 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> AuthorDate: Tue, 18 Apr 2017 19:04:52 +0200 Committer: Thomas Gleixner <tglx@linutronix.de> CommitDate: Thu, 20 Apr 2017 13:08:53 +0200
perf/x86/intel/cqm: Use cpuhp_setup_state_cpuslocked()
intel_cqm_init() holds get_online_cpus() while registerring the hotplug callbacks.
cpuhp_setup_state() invokes get_online_cpus() as well. This is correct, but prevents the conversion of the hotplug locking to a percpu rwsem.
Use cpuhp_setup_state_cpuslocked() to avoid the nested call.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20170418170553.191578891@linutronix.de --- arch/x86/events/intel/cqm.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/arch/x86/events/intel/cqm.c b/arch/x86/events/intel/cqm.c index 8c00dc0..2d4a842 100644 --- a/arch/x86/events/intel/cqm.c +++ b/arch/x86/events/intel/cqm.c @@ -1746,12 +1746,12 @@ static int __init intel_cqm_init(void) * Setup the hot cpu notifier once we are sure cqm * is enabled to avoid notifier leak. */ - cpuhp_setup_state(CPUHP_AP_PERF_X86_CQM_STARTING, - "perf/x86/cqm:starting", - intel_cqm_cpu_starting, NULL); - cpuhp_setup_state(CPUHP_AP_PERF_X86_CQM_ONLINE, "perf/x86/cqm:online", - NULL, intel_cqm_cpu_exit); - + cpuhp_setup_state_cpuslocked(CPUHP_AP_PERF_X86_CQM_STARTING, + "perf/x86/cqm:starting", + intel_cqm_cpu_starting, NULL); + cpuhp_setup_state_cpuslocked(CPUHP_AP_PERF_X86_CQM_ONLINE, + "perf/x86/cqm:online", + NULL, intel_cqm_cpu_exit); out: put_online_cpus();
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