1 /*
2 * Copyright (c) 2018 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 <stdint.h>
30
31 #include <kern/thread.h>
32
33 #include <kperf/action.h>
34 #include <kperf/buffer.h>
35 #include <kperf/kperf.h>
36 #include <kperf/lazy.h>
37 #include <kperf/sample.h>
38
39 unsigned int kperf_lazy_wait_action = 0;
40 unsigned int kperf_lazy_cpu_action = 0;
41 uint64_t kperf_lazy_wait_time_threshold = 0;
42 uint64_t kperf_lazy_cpu_time_threshold = 0;
43
44 void
kperf_lazy_reset(void)45 kperf_lazy_reset(void)
46 {
47 kperf_lazy_wait_action = 0;
48 kperf_lazy_wait_time_threshold = 0;
49 kperf_lazy_cpu_action = 0;
50 kperf_lazy_cpu_time_threshold = 0;
51 kperf_on_cpu_update();
52 }
53
54 void
kperf_lazy_off_cpu(thread_t thread)55 kperf_lazy_off_cpu(thread_t thread)
56 {
57 /* try to lazily sample the CPU if the thread was pre-empted */
58 if ((thread->reason & AST_SCHEDULING) != 0) {
59 kperf_lazy_cpu_sample(thread, 0, 0);
60 }
61 }
62
63 void
kperf_lazy_make_runnable(thread_t thread,bool in_interrupt)64 kperf_lazy_make_runnable(thread_t thread, bool in_interrupt)
65 {
66 assert(thread->last_made_runnable_time != THREAD_NOT_RUNNABLE);
67 /* ignore threads that race to wait and in waking up */
68 if (thread->last_run_time > thread->last_made_runnable_time) {
69 return;
70 }
71
72 uint64_t wait_time = thread_get_last_wait_duration(thread);
73 if (wait_time > kperf_lazy_wait_time_threshold) {
74 BUF_DATA(PERF_LZ_MKRUNNABLE, (uintptr_t)thread_tid(thread),
75 thread->sched_pri, in_interrupt ? 1 : 0);
76 }
77 }
78
79 void
kperf_lazy_wait_sample(thread_t thread,thread_continue_t continuation,uintptr_t * starting_fp)80 kperf_lazy_wait_sample(thread_t thread, thread_continue_t continuation,
81 uintptr_t *starting_fp)
82 {
83 /* ignore idle threads */
84 if (thread->last_made_runnable_time == THREAD_NOT_RUNNABLE) {
85 return;
86 }
87 /* ignore invalid made runnable times */
88 if (thread->last_made_runnable_time < thread->last_run_time) {
89 return;
90 }
91
92 /* take a sample if thread was waiting for longer than threshold */
93 uint64_t wait_time = thread_get_last_wait_duration(thread);
94 if (wait_time > kperf_lazy_wait_time_threshold) {
95 uint64_t runnable_time = timer_grab(&thread->runnable_timer);
96 uint64_t running_time = recount_thread_time_mach(thread);
97
98 BUF_DATA(PERF_LZ_WAITSAMPLE, wait_time, runnable_time, running_time);
99
100 task_t task = get_threadtask(thread);
101 struct kperf_context ctx = {
102 .cur_thread = thread,
103 .cur_task = task,
104 .cur_pid = task_pid(task),
105 .trigger_type = TRIGGER_TYPE_LAZY_WAIT,
106 .starting_fp = starting_fp,
107 };
108
109 struct kperf_sample *sample = kperf_intr_sample_buffer();
110 if (!sample) {
111 return;
112 }
113
114 unsigned int flags = SAMPLE_FLAG_PEND_USER;
115 flags |= continuation ? SAMPLE_FLAG_CONTINUATION : 0;
116 flags |= !ml_at_interrupt_context() ? SAMPLE_FLAG_NON_INTERRUPT : 0;
117
118 kperf_sample(sample, &ctx, kperf_lazy_wait_action, flags);
119 }
120 }
121
122 void
kperf_lazy_cpu_sample(thread_t thread,unsigned int flags,bool interrupt)123 kperf_lazy_cpu_sample(thread_t thread, unsigned int flags, bool interrupt)
124 {
125 assert(ml_get_interrupts_enabled() == FALSE);
126 if (!thread) {
127 thread = current_thread();
128 }
129
130 /* take a sample if this CPU's last sample time is beyond the threshold */
131 processor_t processor = current_processor();
132 #if __arm__ || __arm64__
133 uint64_t time_now = ml_get_speculative_timebase();
134 #else // __arm__ || __arm64__
135 uint64_t time_now = mach_absolute_time();
136 #endif // !__arm__ && !__arm64__
137
138 uint64_t since_last_sample = time_now - processor->kperf_last_sample_time;
139 if (since_last_sample > kperf_lazy_cpu_time_threshold) {
140 processor->kperf_last_sample_time = time_now;
141 uint64_t runnable_time = timer_grab(&thread->runnable_timer);
142 uint64_t running_time = recount_thread_time_mach(thread);
143
144 BUF_DATA(PERF_LZ_CPUSAMPLE, running_time, runnable_time,
145 thread->sched_pri, interrupt ? 1 : 0);
146
147 task_t task = get_threadtask(thread);
148 struct kperf_context ctx = {
149 .cur_thread = thread,
150 .cur_task = task,
151 .cur_pid = task_pid(task),
152 .trigger_type = TRIGGER_TYPE_LAZY_CPU,
153 .starting_fp = 0,
154 };
155
156 struct kperf_sample *sample = kperf_intr_sample_buffer();
157 if (!sample) {
158 return;
159 }
160
161 kperf_sample(sample, &ctx, kperf_lazy_cpu_action,
162 SAMPLE_FLAG_PEND_USER | flags);
163 }
164 }
165
166 /*
167 * Accessors for configuration.
168 */
169
170 int
kperf_lazy_get_wait_action(void)171 kperf_lazy_get_wait_action(void)
172 {
173 return kperf_lazy_wait_action;
174 }
175
176 int
kperf_lazy_set_wait_action(int action_id)177 kperf_lazy_set_wait_action(int action_id)
178 {
179 if (action_id < 0 || (unsigned int)action_id > kperf_action_get_count()) {
180 return 1;
181 }
182
183 kperf_lazy_wait_action = action_id;
184 kperf_on_cpu_update();
185 return 0;
186 }
187
188 uint64_t
kperf_lazy_get_wait_time_threshold(void)189 kperf_lazy_get_wait_time_threshold(void)
190 {
191 return kperf_lazy_wait_time_threshold;
192 }
193
194 int
kperf_lazy_set_wait_time_threshold(uint64_t threshold)195 kperf_lazy_set_wait_time_threshold(uint64_t threshold)
196 {
197 kperf_lazy_wait_time_threshold = threshold;
198 return 0;
199 }
200
201 int
kperf_lazy_get_cpu_action(void)202 kperf_lazy_get_cpu_action(void)
203 {
204 return kperf_lazy_cpu_action;
205 }
206
207 int
kperf_lazy_set_cpu_action(int action_id)208 kperf_lazy_set_cpu_action(int action_id)
209 {
210 if (action_id < 0 || (unsigned int)action_id > kperf_action_get_count()) {
211 return 1;
212 }
213
214 kperf_lazy_cpu_action = action_id;
215 return 0;
216 }
217
218 uint64_t
kperf_lazy_get_cpu_time_threshold(void)219 kperf_lazy_get_cpu_time_threshold(void)
220 {
221 return kperf_lazy_cpu_time_threshold;
222 }
223
224 int
kperf_lazy_set_cpu_time_threshold(uint64_t threshold)225 kperf_lazy_set_cpu_time_threshold(uint64_t threshold)
226 {
227 kperf_lazy_cpu_time_threshold = threshold;
228 return 0;
229 }
230