diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-22 20:36:56 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-22 20:36:56 -0400 |
commit | c54894cd4672d513e43e0d17d7b0387bf6b2c2c4 (patch) | |
tree | 85a540716d82570f98a92b85c66ea5875f983f46 /kernel/trace | |
parent | fb09bafda67041b74a668dc9d77735e36bd33d3b (diff) | |
parent | 4d82a1debbffec129cc387aafa8f40b7bbab3297 (diff) |
Merge branch 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue changes from Tejun Heo:
"Nothing exciting. Most are updates to debug stuff and related fixes.
Two not-too-critical bugs are fixed - WARN_ON() triggering spurious
during cpu offlining and unlikely lockdep related oops."
* 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
lockdep: fix oops in processing workqueue
workqueue: skip nr_running sanity check in worker_enter_idle() if trustee is active
workqueue: Catch more locking problems with flush_work()
workqueue: change BUG_ON() to WARN_ON()
trace: Remove unused workqueue tracer
Diffstat (limited to 'kernel/trace')
-rw-r--r-- | kernel/trace/Makefile | 1 | ||||
-rw-r--r-- | kernel/trace/trace_workqueue.c | 300 |
2 files changed, 0 insertions, 301 deletions
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index 5f39a07fe5ea..b3afe0e76f79 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile | |||
@@ -41,7 +41,6 @@ obj-$(CONFIG_STACK_TRACER) += trace_stack.o | |||
41 | obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o | 41 | obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o |
42 | obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o | 42 | obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o |
43 | obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o | 43 | obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o |
44 | obj-$(CONFIG_WORKQUEUE_TRACER) += trace_workqueue.o | ||
45 | obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o | 44 | obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o |
46 | ifeq ($(CONFIG_BLOCK),y) | 45 | ifeq ($(CONFIG_BLOCK),y) |
47 | obj-$(CONFIG_EVENT_TRACING) += blktrace.o | 46 | obj-$(CONFIG_EVENT_TRACING) += blktrace.o |
diff --git a/kernel/trace/trace_workqueue.c b/kernel/trace/trace_workqueue.c deleted file mode 100644 index 209b379a4721..000000000000 --- a/kernel/trace/trace_workqueue.c +++ /dev/null | |||
@@ -1,300 +0,0 @@ | |||
1 | /* | ||
2 | * Workqueue statistical tracer. | ||
3 | * | ||
4 | * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com> | ||
5 | * | ||
6 | */ | ||
7 | |||
8 | |||
9 | #include <trace/events/workqueue.h> | ||
10 | #include <linux/list.h> | ||
11 | #include <linux/percpu.h> | ||
12 | #include <linux/slab.h> | ||
13 | #include <linux/kref.h> | ||
14 | #include "trace_stat.h" | ||
15 | #include "trace.h" | ||
16 | |||
17 | |||
18 | /* A cpu workqueue thread */ | ||
19 | struct cpu_workqueue_stats { | ||
20 | struct list_head list; | ||
21 | struct kref kref; | ||
22 | int cpu; | ||
23 | pid_t pid; | ||
24 | /* Can be inserted from interrupt or user context, need to be atomic */ | ||
25 | atomic_t inserted; | ||
26 | /* | ||
27 | * Don't need to be atomic, works are serialized in a single workqueue thread | ||
28 | * on a single CPU. | ||
29 | */ | ||
30 | unsigned int executed; | ||
31 | }; | ||
32 | |||
33 | /* List of workqueue threads on one cpu */ | ||
34 | struct workqueue_global_stats { | ||
35 | struct list_head list; | ||
36 | spinlock_t lock; | ||
37 | }; | ||
38 | |||
39 | /* Don't need a global lock because allocated before the workqueues, and | ||
40 | * never freed. | ||
41 | */ | ||
42 | static DEFINE_PER_CPU(struct workqueue_global_stats, all_workqueue_stat); | ||
43 | #define workqueue_cpu_stat(cpu) (&per_cpu(all_workqueue_stat, cpu)) | ||
44 | |||
45 | static void cpu_workqueue_stat_free(struct kref *kref) | ||
46 | { | ||
47 | kfree(container_of(kref, struct cpu_workqueue_stats, kref)); | ||
48 | } | ||
49 | |||
50 | /* Insertion of a work */ | ||
51 | static void | ||
52 | probe_workqueue_insertion(void *ignore, | ||
53 | struct task_struct *wq_thread, | ||
54 | struct work_struct *work) | ||
55 | { | ||
56 | int cpu = cpumask_first(&wq_thread->cpus_allowed); | ||
57 | struct cpu_workqueue_stats *node; | ||
58 | unsigned long flags; | ||
59 | |||
60 | spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); | ||
61 | list_for_each_entry(node, &workqueue_cpu_stat(cpu)->list, list) { | ||
62 | if (node->pid == wq_thread->pid) { | ||
63 | atomic_inc(&node->inserted); | ||
64 | goto found; | ||
65 | } | ||
66 | } | ||
67 | pr_debug("trace_workqueue: entry not found\n"); | ||
68 | found: | ||
69 | spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); | ||
70 | } | ||
71 | |||
72 | /* Execution of a work */ | ||
73 | static void | ||
74 | probe_workqueue_execution(void *ignore, | ||
75 | struct task_struct *wq_thread, | ||
76 | struct work_struct *work) | ||
77 | { | ||
78 | int cpu = cpumask_first(&wq_thread->cpus_allowed); | ||
79 | struct cpu_workqueue_stats *node; | ||
80 | unsigned long flags; | ||
81 | |||
82 | spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); | ||
83 | list_for_each_entry(node, &workqueue_cpu_stat(cpu)->list, list) { | ||
84 | if (node->pid == wq_thread->pid) { | ||
85 | node->executed++; | ||
86 | goto found; | ||
87 | } | ||
88 | } | ||
89 | pr_debug("trace_workqueue: entry not found\n"); | ||
90 | found: | ||
91 | spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); | ||
92 | } | ||
93 | |||
94 | /* Creation of a cpu workqueue thread */ | ||
95 | static void probe_workqueue_creation(void *ignore, | ||
96 | struct task_struct *wq_thread, int cpu) | ||
97 | { | ||
98 | struct cpu_workqueue_stats *cws; | ||
99 | unsigned long flags; | ||
100 | |||
101 | WARN_ON(cpu < 0); | ||
102 | |||
103 | /* Workqueues are sometimes created in atomic context */ | ||
104 | cws = kzalloc(sizeof(struct cpu_workqueue_stats), GFP_ATOMIC); | ||
105 | if (!cws) { | ||
106 | pr_warning("trace_workqueue: not enough memory\n"); | ||
107 | return; | ||
108 | } | ||
109 | INIT_LIST_HEAD(&cws->list); | ||
110 | kref_init(&cws->kref); | ||
111 | cws->cpu = cpu; | ||
112 | cws->pid = wq_thread->pid; | ||
113 | |||
114 | spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); | ||
115 | list_add_tail(&cws->list, &workqueue_cpu_stat(cpu)->list); | ||
116 | spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); | ||
117 | } | ||
118 | |||
119 | /* Destruction of a cpu workqueue thread */ | ||
120 | static void | ||
121 | probe_workqueue_destruction(void *ignore, struct task_struct *wq_thread) | ||
122 | { | ||
123 | /* Workqueue only execute on one cpu */ | ||
124 | int cpu = cpumask_first(&wq_thread->cpus_allowed); | ||
125 | struct cpu_workqueue_stats *node, *next; | ||
126 | unsigned long flags; | ||
127 | |||
128 | spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); | ||
129 | list_for_each_entry_safe(node, next, &workqueue_cpu_stat(cpu)->list, | ||
130 | list) { | ||
131 | if (node->pid == wq_thread->pid) { | ||
132 | list_del(&node->list); | ||
133 | kref_put(&node->kref, cpu_workqueue_stat_free); | ||
134 | goto found; | ||
135 | } | ||
136 | } | ||
137 | |||
138 | pr_debug("trace_workqueue: don't find workqueue to destroy\n"); | ||
139 | found: | ||
140 | spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); | ||
141 | |||
142 | } | ||
143 | |||
144 | static struct cpu_workqueue_stats *workqueue_stat_start_cpu(int cpu) | ||
145 | { | ||
146 | unsigned long flags; | ||
147 | struct cpu_workqueue_stats *ret = NULL; | ||
148 | |||
149 | |||
150 | spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); | ||
151 | |||
152 | if (!list_empty(&workqueue_cpu_stat(cpu)->list)) { | ||
153 | ret = list_entry(workqueue_cpu_stat(cpu)->list.next, | ||
154 | struct cpu_workqueue_stats, list); | ||
155 | kref_get(&ret->kref); | ||
156 | } | ||
157 | |||
158 | spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); | ||
159 | |||
160 | return ret; | ||
161 | } | ||
162 | |||
163 | static void *workqueue_stat_start(struct tracer_stat *trace) | ||
164 | { | ||
165 | int cpu; | ||
166 | void *ret = NULL; | ||
167 | |||
168 | for_each_possible_cpu(cpu) { | ||
169 | ret = workqueue_stat_start_cpu(cpu); | ||
170 | if (ret) | ||
171 | return ret; | ||
172 | } | ||
173 | return NULL; | ||
174 | } | ||
175 | |||
176 | static void *workqueue_stat_next(void *prev, int idx) | ||
177 | { | ||
178 | struct cpu_workqueue_stats *prev_cws = prev; | ||
179 | struct cpu_workqueue_stats *ret; | ||
180 | int cpu = prev_cws->cpu; | ||
181 | unsigned long flags; | ||
182 | |||
183 | spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); | ||
184 | if (list_is_last(&prev_cws->list, &workqueue_cpu_stat(cpu)->list)) { | ||
185 | spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); | ||
186 | do { | ||
187 | cpu = cpumask_next(cpu, cpu_possible_mask); | ||
188 | if (cpu >= nr_cpu_ids) | ||
189 | return NULL; | ||
190 | } while (!(ret = workqueue_stat_start_cpu(cpu))); | ||
191 | return ret; | ||
192 | } else { | ||
193 | ret = list_entry(prev_cws->list.next, | ||
194 | struct cpu_workqueue_stats, list); | ||
195 | kref_get(&ret->kref); | ||
196 | } | ||
197 | spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); | ||
198 | |||
199 | return ret; | ||
200 | } | ||
201 | |||
202 | static int workqueue_stat_show(struct seq_file *s, void *p) | ||
203 | { | ||
204 | struct cpu_workqueue_stats *cws = p; | ||
205 | struct pid *pid; | ||
206 | struct task_struct *tsk; | ||
207 | |||
208 | pid = find_get_pid(cws->pid); | ||
209 | if (pid) { | ||
210 | tsk = get_pid_task(pid, PIDTYPE_PID); | ||
211 | if (tsk) { | ||
212 | seq_printf(s, "%3d %6d %6u %s\n", cws->cpu, | ||
213 | atomic_read(&cws->inserted), cws->executed, | ||
214 | tsk->comm); | ||
215 | put_task_struct(tsk); | ||
216 | } | ||
217 | put_pid(pid); | ||
218 | } | ||
219 | |||
220 | return 0; | ||
221 | } | ||
222 | |||
223 | static void workqueue_stat_release(void *stat) | ||
224 | { | ||
225 | struct cpu_workqueue_stats *node = stat; | ||
226 | |||
227 | kref_put(&node->kref, cpu_workqueue_stat_free); | ||
228 | } | ||
229 | |||
230 | static int workqueue_stat_headers(struct seq_file *s) | ||
231 | { | ||
232 | seq_printf(s, "# CPU INSERTED EXECUTED NAME\n"); | ||
233 | seq_printf(s, "# | | | |\n"); | ||
234 | return 0; | ||
235 | } | ||
236 | |||
237 | struct tracer_stat workqueue_stats __read_mostly = { | ||
238 | .name = "workqueues", | ||
239 | .stat_start = workqueue_stat_start, | ||
240 | .stat_next = workqueue_stat_next, | ||
241 | .stat_show = workqueue_stat_show, | ||
242 | .stat_release = workqueue_stat_release, | ||
243 | .stat_headers = workqueue_stat_headers | ||
244 | }; | ||
245 | |||
246 | |||
247 | int __init stat_workqueue_init(void) | ||
248 | { | ||
249 | if (register_stat_tracer(&workqueue_stats)) { | ||
250 | pr_warning("Unable to register workqueue stat tracer\n"); | ||
251 | return 1; | ||
252 | } | ||
253 | |||
254 | return 0; | ||
255 | } | ||
256 | fs_initcall(stat_workqueue_init); | ||
257 | |||
258 | /* | ||
259 | * Workqueues are created very early, just after pre-smp initcalls. | ||
260 | * So we must register our tracepoints at this stage. | ||
261 | */ | ||
262 | int __init trace_workqueue_early_init(void) | ||
263 | { | ||
264 | int ret, cpu; | ||
265 | |||
266 | for_each_possible_cpu(cpu) { | ||
267 | spin_lock_init(&workqueue_cpu_stat(cpu)->lock); | ||
268 | INIT_LIST_HEAD(&workqueue_cpu_stat(cpu)->list); | ||
269 | } | ||
270 | |||
271 | ret = register_trace_workqueue_insertion(probe_workqueue_insertion, NULL); | ||
272 | if (ret) | ||
273 | goto out; | ||
274 | |||
275 | ret = register_trace_workqueue_execution(probe_workqueue_execution, NULL); | ||
276 | if (ret) | ||
277 | goto no_insertion; | ||
278 | |||
279 | ret = register_trace_workqueue_creation(probe_workqueue_creation, NULL); | ||
280 | if (ret) | ||
281 | goto no_execution; | ||
282 | |||
283 | ret = register_trace_workqueue_destruction(probe_workqueue_destruction, NULL); | ||
284 | if (ret) | ||
285 | goto no_creation; | ||
286 | |||
287 | return 0; | ||
288 | |||
289 | no_creation: | ||
290 | unregister_trace_workqueue_creation(probe_workqueue_creation, NULL); | ||
291 | no_execution: | ||
292 | unregister_trace_workqueue_execution(probe_workqueue_execution, NULL); | ||
293 | no_insertion: | ||
294 | unregister_trace_workqueue_insertion(probe_workqueue_insertion, NULL); | ||
295 | out: | ||
296 | pr_warning("trace_workqueue: unable to trace workqueues\n"); | ||
297 | |||
298 | return 1; | ||
299 | } | ||
300 | early_initcall(trace_workqueue_early_init); | ||