Introduce thread specific data object and array of such objects
to store and manage thread local data. Implement functions to
allocate, initialize, finalize and release thread specific data.
Thread local maps and overwrite_maps arrays keep pointers to
mmap buffer objects to serve according to maps thread mask.
Thread local pollfd array keeps event fds connected to mmaps
buffers according to maps thread mask.
Thread control commands are delivered via thread local comm pipes
and ctlfd_pos fd. External control commands (--control option)
are delivered via evlist ctlfd_pos fd and handled by the main
tool thread.
Signed-off-by: Alexey Bayduraev <[email protected]>
---
tools/lib/api/fd/array.c | 17 ++++
tools/lib/api/fd/array.h | 1 +
tools/perf/builtin-record.c | 194 +++++++++++++++++++++++++++++++++++-
3 files changed, 209 insertions(+), 3 deletions(-)
diff --git a/tools/lib/api/fd/array.c b/tools/lib/api/fd/array.c
index 5e6cb9debe37..de8bcbaea3f1 100644
--- a/tools/lib/api/fd/array.c
+++ b/tools/lib/api/fd/array.c
@@ -88,6 +88,23 @@ int fdarray__add(struct fdarray *fda, int fd, short revents, enum fdarray_flags
return pos;
}
+int fdarray__clone(struct fdarray *fda, int pos, struct fdarray *base)
+{
+ struct pollfd *entry;
+ int npos;
+
+ if (pos >= base->nr)
+ return -EINVAL;
+
+ entry = &base->entries[pos];
+
+ npos = fdarray__add(fda, entry->fd, entry->events, base->priv[pos].flags);
+ if (npos >= 0)
+ fda->priv[npos] = base->priv[pos];
+
+ return npos;
+}
+
int fdarray__filter(struct fdarray *fda, short revents,
void (*entry_destructor)(struct fdarray *fda, int fd, void *arg),
void *arg)
diff --git a/tools/lib/api/fd/array.h b/tools/lib/api/fd/array.h
index 7fcf21a33c0c..4a03da7f1fc1 100644
--- a/tools/lib/api/fd/array.h
+++ b/tools/lib/api/fd/array.h
@@ -42,6 +42,7 @@ struct fdarray *fdarray__new(int nr_alloc, int nr_autogrow);
void fdarray__delete(struct fdarray *fda);
int fdarray__add(struct fdarray *fda, int fd, short revents, enum fdarray_flags flags);
+int fdarray__clone(struct fdarray *fda, int pos, struct fdarray *base);
int fdarray__poll(struct fdarray *fda, int timeout);
int fdarray__filter(struct fdarray *fda, short revents,
void (*entry_destructor)(struct fdarray *fda, int fd, void *arg),
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index e0cbf05d255c..d74fea2d1ca9 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -56,6 +56,7 @@
#include <poll.h>
#include <pthread.h>
#include <unistd.h>
+#include <sys/syscall.h>
#include <sched.h>
#include <signal.h>
#ifdef HAVE_EVENTFD_SUPPORT
@@ -90,6 +91,23 @@ struct thread_mask {
struct mmap_cpu_mask affinity;
};
+struct thread_data {
+ pid_t tid;
+ struct thread_mask *mask;
+ struct {
+ int msg[2];
+ int ack[2];
+ } pipes;
+ struct fdarray pollfd;
+ int ctlfd_pos;
+ struct mmap **maps;
+ struct mmap **overwrite_maps;
+ int nr_mmaps;
+ struct record *rec;
+ unsigned long long samples;
+ unsigned long waking;
+};
+
struct record {
struct perf_tool tool;
struct record_opts opts;
@@ -115,6 +133,7 @@ struct record {
struct mmap_cpu_mask affinity_mask;
unsigned long output_max_size; /* = 0: unlimited */
struct thread_mask *thread_masks;
+ struct thread_data *thread_data;
int nr_threads;
};
@@ -845,9 +864,172 @@ static int record__kcore_copy(struct machine *machine, struct perf_data *data)
return kcore_copy(from_dir, kcore_dir);
}
+static int record__thread_data_init_pipes(struct thread_data *thread_data)
+{
+ if (pipe(thread_data->pipes.msg) || pipe(thread_data->pipes.ack)) {
+ pr_err("Failed to create thread communication pipes, error %m\n");
+ return -ENOMEM;
+ }
+
+ pr_debug2("thread_data[%p]: msg=[%d,%d], ack=[%d,%d]\n", thread_data,
+ thread_data->pipes.msg[0], thread_data->pipes.msg[1],
+ thread_data->pipes.ack[0], thread_data->pipes.ack[1]);
+
+ return 0;
+}
+
+static int record__thread_data_init_maps(struct thread_data *thread_data, struct evlist *evlist)
+{
+ int m, tm, nr_mmaps = evlist->core.nr_mmaps;
+ struct mmap *mmap = evlist->mmap;
+ struct mmap *overwrite_mmap = evlist->overwrite_mmap;
+ struct perf_cpu_map *cpus = evlist->core.cpus;
+
+ thread_data->nr_mmaps = bitmap_weight(thread_data->mask->maps.bits, thread_data->mask->maps.nbits);
+ if (mmap) {
+ thread_data->maps = zalloc(thread_data->nr_mmaps * sizeof(struct mmap *));
+ if (!thread_data->maps) {
+ pr_err("Failed to allocate maps thread data\n");
+ return -ENOMEM;
+ }
+ }
+ if (overwrite_mmap) {
+ thread_data->overwrite_maps = zalloc(thread_data->nr_mmaps * sizeof(struct mmap *));
+ if (!thread_data->overwrite_maps) {
+ pr_err("Failed to allocate overwrite maps thread data\n");
+ return -ENOMEM;
+ }
+ }
+ pr_debug2("thread_data[%p]: nr_mmaps=%d, maps=%p, overwrite_maps=%p\n", thread_data,
+ thread_data->nr_mmaps, thread_data->maps, thread_data->overwrite_maps);
+
+ for (m = 0, tm = 0; m < nr_mmaps && tm < thread_data->nr_mmaps; m++) {
+ if (test_bit(cpus->map[m], thread_data->mask->maps.bits)) {
+ if (thread_data->maps) {
+ thread_data->maps[tm] = &mmap[m];
+ pr_debug2("thread_data[%p]: maps[%d] -> mmap[%d], cpus[%d]\n",
+ thread_data, tm, m, cpus->map[m]);
+ }
+ if (thread_data->overwrite_maps) {
+ thread_data->overwrite_maps[tm] = &overwrite_mmap[m];
+ pr_debug2("thread_data[%p]: overwrite_maps[%d] -> overwrite_mmap[%d], cpus[%d]\n",
+ thread_data, tm, m, cpus->map[m]);
+ }
+ tm++;
+ }
+ }
+
+ return 0;
+}
+
+static int record__thread_data_init_pollfd(struct thread_data *thread_data, struct evlist *evlist)
+{
+ int f, tm, pos;
+ struct mmap *map, *overwrite_map;
+
+ fdarray__init(&thread_data->pollfd, 64);
+
+ for (tm = 0; tm < thread_data->nr_mmaps; tm++) {
+ map = thread_data->maps ? thread_data->maps[tm] : NULL;
+ overwrite_map = thread_data->overwrite_maps ? thread_data->overwrite_maps[tm] : NULL;
+
+ for (f = 0; f < evlist->core.pollfd.nr; f++) {
+ void *ptr = evlist->core.pollfd.priv[f].ptr;
+
+ if ((map && ptr == map) || (overwrite_map && ptr == overwrite_map)) {
+ pos = fdarray__clone(&thread_data->pollfd, f, &evlist->core.pollfd);
+ if (pos < 0)
+ return pos;
+ pr_debug2("thread_data[%p]: pollfd[%d] <- event_fd=%d\n",
+ thread_data, pos, evlist->core.pollfd.entries[f].fd);
+ }
+ }
+ }
+
+ return 0;
+}
+
+static int record__alloc_thread_data(struct record *rec, struct evlist *evlist)
+{
+ int t, ret;
+ struct thread_data *thread_data;
+
+ rec->thread_data = zalloc(rec->nr_threads * sizeof(*(rec->thread_data)));
+ if (!rec->thread_data) {
+ pr_err("Failed to allocate thread data\n");
+ return -ENOMEM;
+ }
+ thread_data = rec->thread_data;
+
+ for (t = 0; t < rec->nr_threads; t++) {
+ thread_data[t].rec = rec;
+ thread_data[t].mask = &rec->thread_masks[t];
+ ret = record__thread_data_init_maps(&thread_data[t], evlist);
+ if (ret)
+ return ret;
+ ret = record__thread_data_init_pollfd(&thread_data[t], evlist);
+ if (ret)
+ return ret;
+ if (t) {
+ thread_data[t].tid = -1;
+ ret = record__thread_data_init_pipes(&thread_data[t]);
+ if (ret)
+ return ret;
+ thread_data[t].ctlfd_pos = fdarray__add(&thread_data[t].pollfd,
+ thread_data[t].pipes.msg[0],
+ POLLIN | POLLERR | POLLHUP,
+ fdarray_flag__nonfilterable);
+ if (thread_data[t].ctlfd_pos < 0)
+ return -ENOMEM;
+ pr_debug2("thread_data[%p]: pollfd[%d] <- ctl_fd=%d\n",
+ thread_data, thread_data[t].ctlfd_pos,
+ thread_data[t].pipes.msg[0]);
+ } else {
+ thread_data[t].tid = syscall(SYS_gettid);
+ if (evlist->ctl_fd.pos == -1)
+ continue;
+ thread_data[t].ctlfd_pos = fdarray__clone(&thread_data[t].pollfd,
+ evlist->ctl_fd.pos,
+ &evlist->core.pollfd);
+ if (thread_data[t].ctlfd_pos < 0)
+ return -ENOMEM;
+ pr_debug2("thread_data[%p]: pollfd[%d] <- ctl_fd=%d\n",
+ thread_data, thread_data[t].ctlfd_pos,
+ evlist->core.pollfd.entries[evlist->ctl_fd.pos].fd);
+ }
+ }
+
+ return 0;
+}
+
+static void record__free_thread_data(struct record *rec)
+{
+ int t;
+
+ if (rec->thread_data == NULL)
+ return;
+
+ for (t = 0; t < rec->nr_threads; t++) {
+ if (rec->thread_data[t].pipes.msg[0])
+ close(rec->thread_data[t].pipes.msg[0]);
+ if (rec->thread_data[t].pipes.msg[1])
+ close(rec->thread_data[t].pipes.msg[1]);
+ if (rec->thread_data[t].pipes.ack[0])
+ close(rec->thread_data[t].pipes.ack[0]);
+ if (rec->thread_data[t].pipes.ack[1])
+ close(rec->thread_data[t].pipes.ack[1]);
+ zfree(&rec->thread_data[t].maps);
+ zfree(&rec->thread_data[t].overwrite_maps);
+ fdarray__exit(&rec->thread_data[t].pollfd);
+ }
+
+ zfree(&rec->thread_data);
+}
+
static int record__mmap_evlist(struct record *rec,
struct evlist *evlist)
{
+ int ret;
struct record_opts *opts = &rec->opts;
bool auxtrace_overwrite = opts->auxtrace_snapshot_mode ||
opts->auxtrace_sample_mode;
@@ -878,6 +1060,14 @@ static int record__mmap_evlist(struct record *rec,
return -EINVAL;
}
}
+
+ if (evlist__initialize_ctlfd(evlist, opts->ctl_fd, opts->ctl_fd_ack))
+ return -1;
+
+ ret = record__alloc_thread_data(rec, evlist);
+ if (ret)
+ return ret;
+
return 0;
}
@@ -1844,9 +2034,6 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
evlist__start_workload(rec->evlist);
}
- if (evlist__initialize_ctlfd(rec->evlist, opts->ctl_fd, opts->ctl_fd_ack))
- goto out_child;
-
if (opts->initial_delay) {
pr_info(EVLIST_DISABLED_MSG);
if (opts->initial_delay > 0) {
@@ -1998,6 +2185,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
record__synthesize_workload(rec, true);
out_child:
+ record__free_thread_data(rec);
evlist__finalize_ctlfd(rec->evlist);
record__mmap_read_all(rec, true);
record__aio_mmap_read_sync(rec);
--
2.19.0
> + } else {
> + thread_data[t].tid = syscall(SYS_gettid);
That always fills in the tid of the setup thread instead of the target
threads?
Hi,
On 08.04.2021 17:16, Andi Kleen wrote:
>> + } else {
>> + thread_data[t].tid = syscall(SYS_gettid);
>
> That always fills in the tid of the setup thread instead of the target
> threads?
>
Here we set the tid for 0-thread (for cpu 0), other threads we setup
later in record__thread(), see [PATCH v4 05/12].
Regards,
Alexey