2 * Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
4 * Parts came from builtin-{top,stat,record}.c, see those files for further
7 * Released under the GPL v2. (and only v2, not any later version)
11 #include "thread_map.h"
18 #include <linux/bitops.h>
19 #include <linux/hash.h>
21 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
22 #define SID(e, x, y) xyarray__entry(e->id, x, y)
24 void perf_evlist__init(struct perf_evlist
*evlist
, struct cpu_map
*cpus
,
25 struct thread_map
*threads
)
29 for (i
= 0; i
< PERF_EVLIST__HLIST_SIZE
; ++i
)
30 INIT_HLIST_HEAD(&evlist
->heads
[i
]);
31 INIT_LIST_HEAD(&evlist
->entries
);
32 perf_evlist__set_maps(evlist
, cpus
, threads
);
35 struct perf_evlist
*perf_evlist__new(struct cpu_map
*cpus
,
36 struct thread_map
*threads
)
38 struct perf_evlist
*evlist
= zalloc(sizeof(*evlist
));
41 perf_evlist__init(evlist
, cpus
, threads
);
46 static void perf_evlist__purge(struct perf_evlist
*evlist
)
48 struct perf_evsel
*pos
, *n
;
50 list_for_each_entry_safe(pos
, n
, &evlist
->entries
, node
) {
51 list_del_init(&pos
->node
);
52 perf_evsel__delete(pos
);
55 evlist
->nr_entries
= 0;
58 void perf_evlist__exit(struct perf_evlist
*evlist
)
63 evlist
->pollfd
= NULL
;
66 void perf_evlist__delete(struct perf_evlist
*evlist
)
68 perf_evlist__purge(evlist
);
69 perf_evlist__exit(evlist
);
73 void perf_evlist__add(struct perf_evlist
*evlist
, struct perf_evsel
*entry
)
75 list_add_tail(&entry
->node
, &evlist
->entries
);
79 int perf_evlist__add_default(struct perf_evlist
*evlist
)
81 struct perf_event_attr attr
= {
82 .type
= PERF_TYPE_HARDWARE
,
83 .config
= PERF_COUNT_HW_CPU_CYCLES
,
85 struct perf_evsel
*evsel
= perf_evsel__new(&attr
, 0);
90 perf_evlist__add(evlist
, evsel
);
94 int perf_evlist__alloc_pollfd(struct perf_evlist
*evlist
)
96 int nfds
= evlist
->cpus
->nr
* evlist
->threads
->nr
* evlist
->nr_entries
;
97 evlist
->pollfd
= malloc(sizeof(struct pollfd
) * nfds
);
98 return evlist
->pollfd
!= NULL
? 0 : -ENOMEM
;
101 void perf_evlist__add_pollfd(struct perf_evlist
*evlist
, int fd
)
103 fcntl(fd
, F_SETFL
, O_NONBLOCK
);
104 evlist
->pollfd
[evlist
->nr_fds
].fd
= fd
;
105 evlist
->pollfd
[evlist
->nr_fds
].events
= POLLIN
;
109 static int perf_evlist__id_hash(struct perf_evlist
*evlist
, struct perf_evsel
*evsel
,
110 int cpu
, int thread
, int fd
)
112 struct perf_sample_id
*sid
;
113 u64 read_data
[4] = { 0, };
114 int hash
, id_idx
= 1; /* The first entry is the counter value */
116 if (!(evsel
->attr
.read_format
& PERF_FORMAT_ID
) ||
117 read(fd
, &read_data
, sizeof(read_data
)) == -1)
120 if (evsel
->attr
.read_format
& PERF_FORMAT_TOTAL_TIME_ENABLED
)
122 if (evsel
->attr
.read_format
& PERF_FORMAT_TOTAL_TIME_RUNNING
)
125 sid
= SID(evsel
, cpu
, thread
);
126 sid
->id
= read_data
[id_idx
];
128 hash
= hash_64(sid
->id
, PERF_EVLIST__HLIST_BITS
);
129 hlist_add_head(&sid
->node
, &evlist
->heads
[hash
]);
133 struct perf_evsel
*perf_evlist__id2evsel(struct perf_evlist
*evlist
, u64 id
)
135 struct hlist_head
*head
;
136 struct hlist_node
*pos
;
137 struct perf_sample_id
*sid
;
140 if (evlist
->nr_entries
== 1)
141 return list_entry(evlist
->entries
.next
, struct perf_evsel
, node
);
143 hash
= hash_64(id
, PERF_EVLIST__HLIST_BITS
);
144 head
= &evlist
->heads
[hash
];
146 hlist_for_each_entry(sid
, pos
, head
, node
)
152 union perf_event
*perf_evlist__read_on_cpu(struct perf_evlist
*evlist
, int cpu
)
154 /* XXX Move this to perf.c, making it generally available */
155 unsigned int page_size
= sysconf(_SC_PAGE_SIZE
);
156 struct perf_mmap
*md
= &evlist
->mmap
[cpu
];
157 unsigned int head
= perf_mmap__read_head(md
);
158 unsigned int old
= md
->prev
;
159 unsigned char *data
= md
->base
+ page_size
;
160 union perf_event
*event
= NULL
;
162 if (evlist
->overwrite
) {
164 * If we're further behind than half the buffer, there's a chance
165 * the writer will bite our tail and mess up the samples under us.
167 * If we somehow ended up ahead of the head, we got messed up.
169 * In either case, truncate and restart at head.
171 int diff
= head
- old
;
172 if (diff
> md
->mask
/ 2 || diff
< 0) {
173 fprintf(stderr
, "WARNING: failed to keep up with mmap data.\n");
176 * head points to a known good entry, start there.
185 event
= (union perf_event
*)&data
[old
& md
->mask
];
186 size
= event
->header
.size
;
189 * Event straddles the mmap boundary -- header should always
190 * be inside due to u64 alignment of output.
192 if ((old
& md
->mask
) + size
!= ((old
+ size
) & md
->mask
)) {
193 unsigned int offset
= old
;
194 unsigned int len
= min(sizeof(*event
), size
), cpy
;
195 void *dst
= &evlist
->event_copy
;
198 cpy
= min(md
->mask
+ 1 - (offset
& md
->mask
), len
);
199 memcpy(dst
, &data
[offset
& md
->mask
], cpy
);
205 event
= &evlist
->event_copy
;
213 if (!evlist
->overwrite
)
214 perf_mmap__write_tail(md
, old
);
219 void perf_evlist__munmap(struct perf_evlist
*evlist
)
223 for (cpu
= 0; cpu
< evlist
->cpus
->nr
; cpu
++) {
224 if (evlist
->mmap
[cpu
].base
!= NULL
) {
225 munmap(evlist
->mmap
[cpu
].base
, evlist
->mmap_len
);
226 evlist
->mmap
[cpu
].base
= NULL
;
231 int perf_evlist__alloc_mmap(struct perf_evlist
*evlist
)
233 evlist
->mmap
= zalloc(evlist
->cpus
->nr
* sizeof(struct perf_mmap
));
234 return evlist
->mmap
!= NULL
? 0 : -ENOMEM
;
237 static int __perf_evlist__mmap(struct perf_evlist
*evlist
, int cpu
, int prot
,
240 evlist
->mmap
[cpu
].prev
= 0;
241 evlist
->mmap
[cpu
].mask
= mask
;
242 evlist
->mmap
[cpu
].base
= mmap(NULL
, evlist
->mmap_len
, prot
,
244 if (evlist
->mmap
[cpu
].base
== MAP_FAILED
)
247 perf_evlist__add_pollfd(evlist
, fd
);
251 /** perf_evlist__mmap - Create per cpu maps to receive events
253 * @evlist - list of events
254 * @pages - map length in pages
255 * @overwrite - overwrite older events?
257 * If overwrite is false the user needs to signal event consuption using:
259 * struct perf_mmap *m = &evlist->mmap[cpu];
260 * unsigned int head = perf_mmap__read_head(m);
262 * perf_mmap__write_tail(m, head)
264 * Using perf_evlist__read_on_cpu does this automatically.
266 int perf_evlist__mmap(struct perf_evlist
*evlist
, int pages
, bool overwrite
)
268 unsigned int page_size
= sysconf(_SC_PAGE_SIZE
);
269 int mask
= pages
* page_size
- 1, cpu
;
270 struct perf_evsel
*first_evsel
, *evsel
;
271 const struct cpu_map
*cpus
= evlist
->cpus
;
272 const struct thread_map
*threads
= evlist
->threads
;
273 int thread
, prot
= PROT_READ
| (overwrite
? 0 : PROT_WRITE
);
275 if (evlist
->mmap
== NULL
&& perf_evlist__alloc_mmap(evlist
) < 0)
278 if (evlist
->pollfd
== NULL
&& perf_evlist__alloc_pollfd(evlist
) < 0)
281 evlist
->overwrite
= overwrite
;
282 evlist
->mmap_len
= (pages
+ 1) * page_size
;
283 first_evsel
= list_entry(evlist
->entries
.next
, struct perf_evsel
, node
);
285 list_for_each_entry(evsel
, &evlist
->entries
, node
) {
286 if ((evsel
->attr
.read_format
& PERF_FORMAT_ID
) &&
288 perf_evsel__alloc_id(evsel
, cpus
->nr
, threads
->nr
) < 0)
291 for (cpu
= 0; cpu
< cpus
->nr
; cpu
++) {
292 for (thread
= 0; thread
< threads
->nr
; thread
++) {
293 int fd
= FD(evsel
, cpu
, thread
);
295 if (evsel
->idx
|| thread
) {
296 if (ioctl(fd
, PERF_EVENT_IOC_SET_OUTPUT
,
297 FD(first_evsel
, cpu
, 0)) != 0)
299 } else if (__perf_evlist__mmap(evlist
, cpu
, prot
, mask
, fd
) < 0)
302 if ((evsel
->attr
.read_format
& PERF_FORMAT_ID
) &&
303 perf_evlist__id_hash(evlist
, evsel
, cpu
, thread
, fd
) < 0)
312 for (cpu
= 0; cpu
< cpus
->nr
; cpu
++) {
313 if (evlist
->mmap
[cpu
].base
!= NULL
) {
314 munmap(evlist
->mmap
[cpu
].base
, evlist
->mmap_len
);
315 evlist
->mmap
[cpu
].base
= NULL
;
321 int perf_evlist__create_maps(struct perf_evlist
*evlist
, pid_t target_pid
,
322 pid_t target_tid
, const char *cpu_list
)
324 evlist
->threads
= thread_map__new(target_pid
, target_tid
);
326 if (evlist
->threads
== NULL
)
329 if (target_tid
!= -1)
330 evlist
->cpus
= cpu_map__dummy_new();
332 evlist
->cpus
= cpu_map__new(cpu_list
);
334 if (evlist
->cpus
== NULL
)
335 goto out_delete_threads
;
340 thread_map__delete(evlist
->threads
);
344 void perf_evlist__delete_maps(struct perf_evlist
*evlist
)
346 cpu_map__delete(evlist
->cpus
);
347 thread_map__delete(evlist
->threads
);
349 evlist
->threads
= NULL
;