Commit-ID: 04b247c2ebdd6ba1c46c7c22546229a89760b43a Gitweb: http://git.kernel.org/tip/04b247c2ebdd6ba1c46c7c22546229a89760b43a Author: Sebastian Andrzej Siewior <[email protected]> AuthorDate: Wed, 24 May 2017 10:15:24 +0200 Committer: Thomas Gleixner <[email protected]> CommitDate: Fri, 26 May 2017 10:10:40 +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. Convert *_online_cpus() to the new interfaces while at it. Signed-off-by: Sebastian Andrzej Siewior <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Ingo Molnar <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Steven Rostedt <[email protected]> Link: http://lkml.kernel.org/r/[email protected] --- arch/x86/events/intel/cqm.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/x86/events/intel/cqm.c b/arch/x86/events/intel/cqm.c index 8c00dc0..2521f77 100644 --- a/arch/x86/events/intel/cqm.c +++ b/arch/x86/events/intel/cqm.c @@ -1682,7 +1682,7 @@ static int __init intel_cqm_init(void) * * Also, check that the scales match on all cpus. */ - get_online_cpus(); + cpus_read_lock(); for_each_online_cpu(cpu) { struct cpuinfo_x86 *c = &cpu_data(cpu); @@ -1746,14 +1746,14 @@ 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(); + cpus_read_unlock(); if (ret) { kfree(str);
