base/process/process_mac.cc

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/process/process.h"
   6
   7 #include "base/mac/mac_util.h"
   8 #include "base/mac/mach_logging.h"
   9
  10 #include <mach/mach.h>
  11
  12 // The following was added to <mach/task_policy.h> after 10.8.
  13 // TODO(shrike): Remove the TASK_OVERRIDE_QOS_POLICY ifndef once builders
  14 // reach 10.9 or higher.
  15 #ifndef TASK_OVERRIDE_QOS_POLICY
  16
  17 #define TASK_OVERRIDE_QOS_POLICY 9
  18
  19 typedef struct task_category_policy task_category_policy_data_t;
  20 typedef struct task_category_policy* task_category_policy_t;
  21
  22 enum task_latency_qos {
  23   LATENCY_QOS_TIER_UNSPECIFIED = 0x0,
  24   LATENCY_QOS_TIER_0 = ((0xFF << 16) | 1),
  25   LATENCY_QOS_TIER_1 = ((0xFF << 16) | 2),
  26   LATENCY_QOS_TIER_2 = ((0xFF << 16) | 3),
  27   LATENCY_QOS_TIER_3 = ((0xFF << 16) | 4),
  28   LATENCY_QOS_TIER_4 = ((0xFF << 16) | 5),
  29   LATENCY_QOS_TIER_5 = ((0xFF << 16) | 6)
  30 };
  31 typedef integer_t task_latency_qos_t;
  32 enum task_throughput_qos {
  33   THROUGHPUT_QOS_TIER_UNSPECIFIED = 0x0,
  34   THROUGHPUT_QOS_TIER_0 = ((0xFE << 16) | 1),
  35   THROUGHPUT_QOS_TIER_1 = ((0xFE << 16) | 2),
  36   THROUGHPUT_QOS_TIER_2 = ((0xFE << 16) | 3),
  37   THROUGHPUT_QOS_TIER_3 = ((0xFE << 16) | 4),
  38   THROUGHPUT_QOS_TIER_4 = ((0xFE << 16) | 5),
  39   THROUGHPUT_QOS_TIER_5 = ((0xFE << 16) | 6),
  40 };
  41
  42 #define LATENCY_QOS_LAUNCH_DEFAULT_TIER LATENCY_QOS_TIER_3
  43 #define THROUGHPUT_QOS_LAUNCH_DEFAULT_TIER THROUGHPUT_QOS_TIER_3
  44
  45 typedef integer_t task_throughput_qos_t;
  46
  47 struct task_qos_policy {
  48   task_latency_qos_t task_latency_qos_tier;
  49   task_throughput_qos_t task_throughput_qos_tier;
  50 };
  51
  52 typedef struct task_qos_policy* task_qos_policy_t;
  53 #define TASK_QOS_POLICY_COUNT \
  54   ((mach_msg_type_number_t)(sizeof(struct task_qos_policy) / sizeof(integer_t)))
  55
  56 #endif  // TASK_OVERRIDE_QOS_POLICY
  57
  58 namespace base {
  59
  60 bool Process::CanBackgroundProcesses() {
  61   return true;
  62 }
  63
  64 bool Process::IsProcessBackgrounded(mach_port_t task_port) const {
  65   // See SetProcessBackgrounded().
  66   DCHECK(IsValid());
  67   DCHECK_NE(task_port, TASK_NULL);
  68
  69   task_category_policy_data_t category_policy;
  70   mach_msg_type_number_t task_info_count = TASK_CATEGORY_POLICY_COUNT;
  71   boolean_t get_default = FALSE;
  72
  73   kern_return_t result =
  74       task_policy_get(task_port, TASK_CATEGORY_POLICY,
  75                       reinterpret_cast<task_policy_t>(&category_policy),
  76                       &task_info_count, &get_default);
  77   MACH_LOG_IF(ERROR, result != KERN_SUCCESS, result) <<
  78       "task_policy_get TASK_CATEGORY_POLICY";
  79
  80   if (result == KERN_SUCCESS && get_default == FALSE) {
  81     return category_policy.role == TASK_BACKGROUND_APPLICATION;
  82   }
  83   return false;
  84 }
  85
  86 bool Process::SetProcessBackgrounded(mach_port_t task_port, bool background) {
  87   DCHECK(IsValid());
  88   DCHECK_NE(task_port, TASK_NULL);
  89
  90   if (!CanBackgroundProcesses()) {
  91     return false;
  92   } else if (IsProcessBackgrounded(task_port) == background) {
  93     return true;
  94   }
  95
  96   task_category_policy category_policy;
  97   category_policy.role =
  98       background ? TASK_BACKGROUND_APPLICATION : TASK_FOREGROUND_APPLICATION;
  99   kern_return_t result =
 100       task_policy_set(task_port, TASK_CATEGORY_POLICY,
 101                       reinterpret_cast<task_policy_t>(&category_policy),
 102                       TASK_CATEGORY_POLICY_COUNT);
 103
 104   if (result != KERN_SUCCESS) {
 105     MACH_LOG(ERROR, result) << "task_policy_set TASK_CATEGORY_POLICY";
 106     return false;
 107   } else if (!mac::IsOSMavericksOrLater()) {
 108     return true;
 109   }
 110
 111   // Latency QoS regulates timer throttling/accuracy. Select default tier
 112   // on foreground because precise timer firing isn't needed.
 113   struct task_qos_policy qos_policy = {
 114       background ? LATENCY_QOS_TIER_5 : LATENCY_QOS_TIER_UNSPECIFIED,
 115       background ? THROUGHPUT_QOS_TIER_5 : THROUGHPUT_QOS_TIER_UNSPECIFIED
 116   };
 117   result = task_policy_set(task_port, TASK_OVERRIDE_QOS_POLICY,
 118                            reinterpret_cast<task_policy_t>(&qos_policy),
 119                            TASK_QOS_POLICY_COUNT);
 120   if (result != KERN_SUCCESS) {
 121     MACH_LOG(ERROR, result) << "task_policy_set TASK_OVERRIDE_QOS_POLICY";
 122     return false;
 123   }
 124
 125   return true;
 126 }
 127
 128 }  // namespace base