osfmk/kperf/x86_64/kperf_mp.c

   1 /*
   2  * Copyright (c) 2011-2016 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 #include <i386/mp.h>
  30 #include <mach/mach_types.h>
  31 #include <kern/processor.h>
  32 #include <kperf/buffer.h>
  33 #include <kperf/kperf.h>
  34 #include <kperf/kperf_arch.h>
  35 #include <kperf/kperf_timer.h>
  36 #include <stdatomic.h>
  37
  38 bool
  39 kperf_mp_broadcast_other_running(struct kperf_timer *trigger)
  40 {
  41         int current_cpu = cpu_number();
  42         int ncpus = machine_info.logical_cpu_max;
  43         bool system_only_self = true;
  44         cpumask_t cpu_mask = 0;
  45
  46         for (int i = 0; i < ncpus; i++) {
  47                 uint64_t i_bit = UINT64_C(1) << i;
  48                 processor_t processor = cpu_to_processor(i);
  49
  50                 /* do not IPI processors that are not scheduling threads */
  51                 if (processor == PROCESSOR_NULL ||
  52                                 processor->state != PROCESSOR_RUNNING ||
  53                                 processor->active_thread == THREAD_NULL)
  54                 {
  55 #if DEVELOPMENT || DEBUG
  56                         BUF_VERB(PERF_TM_SKIPPED, i,
  57                                         processor != PROCESSOR_NULL ? processor->state : 0,
  58                                         processor != PROCESSOR_NULL ? processor->active_thread : 0);
  59 #endif /* DEVELOPMENT || DEBUG */
  60                         continue;
  61                 }
  62
  63                 /* don't run the handler on the current processor */
  64                 if (i == current_cpu) {
  65                         system_only_self = false;
  66                         continue;
  67                 }
  68
  69                 /* nor processors that have not responded to the last IPI */
  70                 uint64_t already_pending = atomic_fetch_or_explicit(
  71                                 &trigger->pending_cpus, i_bit,
  72                                 memory_order_relaxed);
  73                 if (already_pending & i_bit) {
  74 #if DEVELOPMENT || DEBUG
  75                         BUF_VERB(PERF_TM_PENDING, i_bit, already_pending);
  76                         atomic_fetch_add_explicit(&kperf_pending_ipis, 1,
  77                                         memory_order_relaxed);
  78 #endif /* DEVELOPMENT || DEBUG */
  79                         continue;
  80                 }
  81
  82                 cpu_mask |= cpu_to_cpumask(i);
  83         }
  84
  85         if (cpu_mask != 0) {
  86                 mp_cpus_call(cpu_mask, NOSYNC, kperf_ipi_handler, trigger);
  87         }
  88
  89         return system_only_self;
  90 }