perf evsel: Introduce mmap support
Out of the code in 'perf top'. Record is next in line.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 15d89be..7d723ad 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -1095,43 +1095,12 @@
}
}
-struct mmap_data {
- void *base;
- int mask;
- unsigned int prev;
-};
-
-static int perf_evsel__alloc_mmap_per_thread(struct perf_evsel *evsel,
- int ncpus, int nthreads)
-{
- evsel->priv = xyarray__new(ncpus, nthreads, sizeof(struct mmap_data));
- return evsel->priv != NULL ? 0 : -ENOMEM;
-}
-
-static void perf_evsel__free_mmap(struct perf_evsel *evsel)
-{
- xyarray__delete(evsel->priv);
- evsel->priv = NULL;
-}
-
-static unsigned int mmap_read_head(struct mmap_data *md)
-{
- struct perf_event_mmap_page *pc = md->base;
- int head;
-
- head = pc->data_head;
- rmb();
-
- return head;
-}
-
static void perf_session__mmap_read_counter(struct perf_session *self,
struct perf_evsel *evsel,
int cpu, int thread_idx)
{
- struct xyarray *mmap_array = evsel->priv;
- struct mmap_data *md = xyarray__entry(mmap_array, cpu, thread_idx);
- unsigned int head = mmap_read_head(md);
+ struct perf_mmap *md = xyarray__entry(evsel->mmap, cpu, thread_idx);
+ unsigned int head = perf_mmap__read_head(md);
unsigned int old = md->prev;
unsigned char *data = md->base + page_size;
struct sample_data sample;
@@ -1210,35 +1179,9 @@
}
}
-static void start_counter(int i, struct perf_evlist *evlist,
- struct perf_evsel *evsel)
-{
- struct xyarray *mmap_array = evsel->priv;
- struct mmap_data *mm;
- int thread_index;
-
- for (thread_index = 0; thread_index < threads->nr; thread_index++) {
- assert(FD(evsel, i, thread_index) >= 0);
- fcntl(FD(evsel, i, thread_index), F_SETFL, O_NONBLOCK);
-
- evlist->pollfd[evlist->nr_fds].fd = FD(evsel, i, thread_index);
- evlist->pollfd[evlist->nr_fds].events = POLLIN;
- evlist->nr_fds++;
-
- mm = xyarray__entry(mmap_array, i, thread_index);
- mm->prev = 0;
- mm->mask = mmap_pages*page_size - 1;
- mm->base = mmap(NULL, (mmap_pages+1)*page_size,
- PROT_READ, MAP_SHARED, FD(evsel, i, thread_index), 0);
- if (mm->base == MAP_FAILED)
- die("failed to mmap with %d (%s)\n", errno, strerror(errno));
- }
-}
-
static void start_counters(struct perf_evlist *evlist)
{
struct perf_evsel *counter;
- int i;
list_for_each_entry(counter, &evlist->entries, node) {
struct perf_event_attr *attr = &counter->attr;
@@ -1282,11 +1225,9 @@
die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
exit(-1);
}
- }
- for (i = 0; i < cpus->nr; i++) {
- list_for_each_entry(counter, &evlist->entries, node)
- start_counter(i, evsel_list, counter);
+ if (perf_evsel__mmap(counter, cpus, threads, mmap_pages, evlist) < 0)
+ die("failed to mmap with %d (%s)\n", errno, strerror(errno));
}
}
@@ -1453,7 +1394,7 @@
usage_with_options(top_usage, options);
list_for_each_entry(pos, &evsel_list->entries, node) {
- if (perf_evsel__alloc_mmap_per_thread(pos, cpus->nr, threads->nr) < 0 ||
+ if (perf_evsel__alloc_mmap(pos, cpus->nr, threads->nr) < 0 ||
perf_evsel__alloc_fd(pos, cpus->nr, threads->nr) < 0)
goto out_free_fd;
/*
@@ -1485,8 +1426,6 @@
status = __cmd_top();
out_free_fd:
- list_for_each_entry(pos, &evsel_list->entries, node)
- perf_evsel__free_mmap(pos);
perf_evlist__delete(evsel_list);
return status;