diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2016-02-22 22:19:20 (GMT) |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2016-02-29 08:35:21 (GMT) |
commit | 827db839cd051cfde5a618fb4427e86dc91bc9aa (patch) | |
tree | bdd2a35e576e14bba45bc9138cb9feaf1715f159 /arch/x86/events/intel | |
parent | 3712bba1a260ad851f3aa8ddea9cb7326f6aa0b3 (diff) | |
download | linux-827db839cd051cfde5a618fb4427e86dc91bc9aa.tar.xz |
perf/x86/intel/cqm: Get rid of the silly for_each_cpu() lookups
CQM is a strict per package facility. Use the proper cpumasks to lookup the
readers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Harish Chegondi <harish.chegondi@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20160222221012.054916179@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/events/intel')
-rw-r--r-- | arch/x86/events/intel/cqm.c | 32 |
1 files changed, 11 insertions, 21 deletions
diff --git a/arch/x86/events/intel/cqm.c b/arch/x86/events/intel/cqm.c index 1b064c4..93cb412 100644 --- a/arch/x86/events/intel/cqm.c +++ b/arch/x86/events/intel/cqm.c @@ -1244,15 +1244,12 @@ static struct pmu intel_cqm_pmu = { static inline void cqm_pick_event_reader(int cpu) { - int phys_id = topology_physical_package_id(cpu); - int i; + int reader; - for_each_cpu(i, &cqm_cpumask) { - if (phys_id == topology_physical_package_id(i)) - return; /* already got reader for this socket */ - } - - cpumask_set_cpu(cpu, &cqm_cpumask); + /* First online cpu in package becomes the reader */ + reader = cpumask_any_and(&cqm_cpumask, topology_core_cpumask(cpu)); + if (reader >= nr_cpu_ids) + cpumask_set_cpu(cpu, &cqm_cpumask); } static void intel_cqm_cpu_starting(unsigned int cpu) @@ -1270,24 +1267,17 @@ static void intel_cqm_cpu_starting(unsigned int cpu) static void intel_cqm_cpu_exit(unsigned int cpu) { - int phys_id = topology_physical_package_id(cpu); - int i; + int target; - /* - * Is @cpu a designated cqm reader? - */ + /* Is @cpu the current cqm reader for this package ? */ if (!cpumask_test_and_clear_cpu(cpu, &cqm_cpumask)) return; - for_each_online_cpu(i) { - if (i == cpu) - continue; + /* Find another online reader in this package */ + target = cpumask_any_but(topology_core_cpumask(cpu), cpu); - if (phys_id == topology_physical_package_id(i)) { - cpumask_set_cpu(i, &cqm_cpumask); - break; - } - } + if (target < nr_cpu_ids) + cpumask_set_cpu(target, &cqm_cpumask); } static int intel_cqm_cpu_notifier(struct notifier_block *nb, |