[PATCH 29/54] perf mmap: Simplify perf_mmap__read_init()

From: Arnaldo Carvalho de Melo
Date: Thu Mar 08 2018 - 15:01:35 EST

From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

It isn't necessary to pass the 'start', 'end' and 'overwrite' arguments
to perf_mmap__read_init(). The data is stored in the struct perf_mmap.

Discard the parameters.

Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Suggested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1520350567-80082-8-git-send-email-kan.liang@xxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/arch/x86/tests/perf-time-to-tsc.c | 3 +--
tools/perf/builtin-kvm.c | 3 +--
tools/perf/builtin-top.c | 3 +--
tools/perf/builtin-trace.c | 3 +--
tools/perf/tests/backward-ring-buffer.c | 3 +--
tools/perf/tests/bpf.c | 3 +--
tools/perf/tests/code-reading.c | 3 +--
tools/perf/tests/keep-tracking.c | 3 +--
tools/perf/tests/mmap-basic.c | 3 +--
tools/perf/tests/openat-syscall-tp-fields.c | 3 +--
tools/perf/tests/perf-record.c | 3 +--
tools/perf/tests/sw-clock.c | 3 +--
tools/perf/tests/switch-tracking.c | 3 +--
tools/perf/tests/task-exit.c | 3 +--
tools/perf/util/mmap.c | 10 ++--------
tools/perf/util/mmap.h | 3 +--
tools/perf/util/python.c | 3 +--
17 files changed, 18 insertions(+), 40 deletions(-)

diff --git a/tools/perf/arch/x86/tests/perf-time-to-tsc.c b/tools/perf/arch/x86/tests/perf-time-to-tsc.c
index 17cf7fc3c7d5..7a7721604b86 100644
--- a/tools/perf/arch/x86/tests/perf-time-to-tsc.c
+++ b/tools/perf/arch/x86/tests/perf-time-to-tsc.c
@@ -61,7 +61,6 @@ int test__perf_time_to_tsc(struct test *test __maybe_unused, int subtest __maybe
u64 test_tsc, comm1_tsc, comm2_tsc;
u64 test_time, comm1_time = 0, comm2_time = 0;
struct perf_mmap *md;
- u64 end, start;

threads = thread_map__new(-1, getpid(), UINT_MAX);
CHECK_NOT_NULL__(threads);
@@ -112,7 +111,7 @@ int test__perf_time_to_tsc(struct test *test __maybe_unused, int subtest __maybe

for (i = 0; i < evlist->nr_mmaps; i++) {
md = &evlist->mmap[i];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
continue;

while ((event = perf_mmap__read_event(md)) != NULL) {
diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c
index e9f69b8f8e25..72e2ca096bf5 100644
--- a/tools/perf/builtin-kvm.c
+++ b/tools/perf/builtin-kvm.c
@@ -746,14 +746,13 @@ static s64 perf_kvm__mmap_read_idx(struct perf_kvm_stat *kvm, int idx,
struct perf_evlist *evlist = kvm->evlist;
union perf_event *event;
struct perf_mmap *md;
- u64 end, start;
u64 timestamp;
s64 n = 0;
int err;

*mmap_time = ULLONG_MAX;
md = &evlist->mmap[idx];
- err = perf_mmap__read_init(md, false, &start, &end);
+ err = perf_mmap__read_init(md);
if (err < 0)
return (err == -EAGAIN) ? 0 : -1;

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index eb19cf92a388..0a26b56afcc5 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -817,11 +817,10 @@ static void perf_top__mmap_read_idx(struct perf_top *top, int idx)
struct perf_session *session = top->session;
union perf_event *event;
struct machine *machine;
- u64 end, start;
int ret;

md = opts->overwrite ? &evlist->overwrite_mmap[idx] : &evlist->mmap[idx];
- if (perf_mmap__read_init(md, opts->overwrite, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
return;

while ((event = perf_mmap__read_event(md)) != NULL) {
diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 29fda506ac75..87b95c9410b4 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -2503,10 +2503,9 @@ static int trace__run(struct trace *trace, int argc, const char **argv)
for (i = 0; i < evlist->nr_mmaps; i++) {
union perf_event *event;
struct perf_mmap *md;
- u64 end, start;

md = &evlist->mmap[i];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
continue;

while ((event = perf_mmap__read_event(md)) != NULL) {
diff --git a/tools/perf/tests/backward-ring-buffer.c b/tools/perf/tests/backward-ring-buffer.c
index e0eae1053ddc..6d598cc071ae 100644
--- a/tools/perf/tests/backward-ring-buffer.c
+++ b/tools/perf/tests/backward-ring-buffer.c
@@ -33,9 +33,8 @@ static int count_samples(struct perf_evlist *evlist, int *sample_count,
for (i = 0; i < evlist->nr_mmaps; i++) {
struct perf_mmap *map = &evlist->overwrite_mmap[i];
union perf_event *event;
- u64 start, end;

- perf_mmap__read_init(map, true, &start, &end);
+ perf_mmap__read_init(map);
while ((event = perf_mmap__read_event(map)) != NULL) {
const u32 type = event->header.type;

diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
index 384c20f4c902..79b54f8ddebf 100644
--- a/tools/perf/tests/bpf.c
+++ b/tools/perf/tests/bpf.c
@@ -177,10 +177,9 @@ static int do_test(struct bpf_object *obj, int (*func)(void),
for (i = 0; i < evlist->nr_mmaps; i++) {
union perf_event *event;
struct perf_mmap *md;
- u64 end, start;

md = &evlist->mmap[i];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
continue;

while ((event = perf_mmap__read_event(md)) != NULL) {
diff --git a/tools/perf/tests/code-reading.c b/tools/perf/tests/code-reading.c
index f7919666bc2c..99936352df4f 100644
--- a/tools/perf/tests/code-reading.c
+++ b/tools/perf/tests/code-reading.c
@@ -410,12 +410,11 @@ static int process_events(struct machine *machine, struct perf_evlist *evlist,
{
union perf_event *event;
struct perf_mmap *md;
- u64 end, start;
int i, ret;

for (i = 0; i < evlist->nr_mmaps; i++) {
md = &evlist->mmap[i];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
continue;

while ((event = perf_mmap__read_event(md)) != NULL) {
diff --git a/tools/perf/tests/keep-tracking.c b/tools/perf/tests/keep-tracking.c
index ad477b7cf238..17c46f3e6f1e 100644
--- a/tools/perf/tests/keep-tracking.c
+++ b/tools/perf/tests/keep-tracking.c
@@ -28,13 +28,12 @@ static int find_comm(struct perf_evlist *evlist, const char *comm)
{
union perf_event *event;
struct perf_mmap *md;
- u64 end, start;
int i, found;

found = 0;
for (i = 0; i < evlist->nr_mmaps; i++) {
md = &evlist->mmap[i];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
continue;
while ((event = perf_mmap__read_event(md)) != NULL) {
if (event->header.type == PERF_RECORD_COMM &&
diff --git a/tools/perf/tests/mmap-basic.c b/tools/perf/tests/mmap-basic.c
index 7790eb3303e6..bb8e6bcb0d96 100644
--- a/tools/perf/tests/mmap-basic.c
+++ b/tools/perf/tests/mmap-basic.c
@@ -39,7 +39,6 @@ int test__basic_mmap(struct test *test __maybe_unused, int subtest __maybe_unuse
struct perf_evsel *evsels[nsyscalls], *evsel;
char sbuf[STRERR_BUFSIZE];
struct perf_mmap *md;
- u64 end, start;

threads = thread_map__new(-1, getpid(), UINT_MAX);
if (threads == NULL) {
@@ -109,7 +108,7 @@ int test__basic_mmap(struct test *test __maybe_unused, int subtest __maybe_unuse
}

md = &evlist->mmap[0];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
goto out_init;

while ((event = perf_mmap__read_event(md)) != NULL) {
diff --git a/tools/perf/tests/openat-syscall-tp-fields.c b/tools/perf/tests/openat-syscall-tp-fields.c
index b0be2da65da7..344dc3ac2469 100644
--- a/tools/perf/tests/openat-syscall-tp-fields.c
+++ b/tools/perf/tests/openat-syscall-tp-fields.c
@@ -87,10 +87,9 @@ int test__syscall_openat_tp_fields(struct test *test __maybe_unused, int subtest
for (i = 0; i < evlist->nr_mmaps; i++) {
union perf_event *event;
struct perf_mmap *md;
- u64 end, start;

md = &evlist->mmap[i];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
continue;

while ((event = perf_mmap__read_event(md)) != NULL) {
diff --git a/tools/perf/tests/perf-record.c b/tools/perf/tests/perf-record.c
index 59be0942b787..34394cc05077 100644
--- a/tools/perf/tests/perf-record.c
+++ b/tools/perf/tests/perf-record.c
@@ -165,10 +165,9 @@ int test__PERF_RECORD(struct test *test __maybe_unused, int subtest __maybe_unus
for (i = 0; i < evlist->nr_mmaps; i++) {
union perf_event *event;
struct perf_mmap *md;
- u64 end, start;

md = &evlist->mmap[i];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
continue;

while ((event = perf_mmap__read_event(md)) != NULL) {
diff --git a/tools/perf/tests/sw-clock.c b/tools/perf/tests/sw-clock.c
index 403f2d9cee96..f9490b237893 100644
--- a/tools/perf/tests/sw-clock.c
+++ b/tools/perf/tests/sw-clock.c
@@ -40,7 +40,6 @@ static int __test__sw_clock_freq(enum perf_sw_ids clock_id)
struct cpu_map *cpus;
struct thread_map *threads;
struct perf_mmap *md;
- u64 end, start;

attr.sample_freq = 500;

@@ -96,7 +95,7 @@ static int __test__sw_clock_freq(enum perf_sw_ids clock_id)
perf_evlist__disable(evlist);

md = &evlist->mmap[0];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
goto out_init;

while ((event = perf_mmap__read_event(md)) != NULL) {
diff --git a/tools/perf/tests/switch-tracking.c b/tools/perf/tests/switch-tracking.c
index 99839de3caee..9b5be51e5e7b 100644
--- a/tools/perf/tests/switch-tracking.c
+++ b/tools/perf/tests/switch-tracking.c
@@ -259,12 +259,11 @@ static int process_events(struct perf_evlist *evlist,
LIST_HEAD(events);
struct event_node *events_array, *node;
struct perf_mmap *md;
- u64 end, start;
int i, ret;

for (i = 0; i < evlist->nr_mmaps; i++) {
md = &evlist->mmap[i];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
continue;

while ((event = perf_mmap__read_event(md)) != NULL) {
diff --git a/tools/perf/tests/task-exit.c b/tools/perf/tests/task-exit.c
index 2df0c0573e2c..e92fa6029ac7 100644
--- a/tools/perf/tests/task-exit.c
+++ b/tools/perf/tests/task-exit.c
@@ -48,7 +48,6 @@ int test__task_exit(struct test *test __maybe_unused, int subtest __maybe_unused
struct cpu_map *cpus;
struct thread_map *threads;
struct perf_mmap *md;
- u64 end, start;

signal(SIGCHLD, sig_handler);

@@ -113,7 +112,7 @@ int test__task_exit(struct test *test __maybe_unused, int subtest __maybe_unused

retry:
md = &evlist->mmap[0];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
goto out_init;

while ((event = perf_mmap__read_event(md)) != NULL) {
diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c
index 2fbe4c8a02d2..074c4fd3b67e 100644
--- a/tools/perf/util/mmap.c
+++ b/tools/perf/util/mmap.c
@@ -235,16 +235,13 @@ static int overwrite_rb_find_range(void *buf, int mask, u64 head, u64 *start, u6
/*
* Report the start and end of the available data in ringbuffer
*/
-int perf_mmap__read_init(struct perf_mmap *md, bool overwrite,
- u64 *startp, u64 *endp)
+int perf_mmap__read_init(struct perf_mmap *md)
{
u64 head = perf_mmap__read_head(md);
u64 old = md->prev;
unsigned char *data = md->base + page_size;
unsigned long size;

- *startp = overwrite ? head : old;
- *endp = overwrite ? old : head;
md->start = md->overwrite ? head : old;
md->end = md->overwrite ? old : head;

@@ -267,8 +264,6 @@ int perf_mmap__read_init(struct perf_mmap *md, bool overwrite,
*/
if (overwrite_rb_find_range(data, md->mask, head, &md->start, &md->end))
return -EINVAL;
- *startp = md->start;
- *endp = md->end;
}

return 0;
@@ -278,13 +273,12 @@ int perf_mmap__push(struct perf_mmap *md, void *to,
int push(void *to, void *buf, size_t size))
{
u64 head = perf_mmap__read_head(md);
- u64 end, start;
unsigned char *data = md->base + page_size;
unsigned long size;
void *buf;
int rc = 0;

- rc = perf_mmap__read_init(md, md->overwrite, &start, &end);
+ rc = perf_mmap__read_init(md);
if (rc < 0)
return (rc == -EAGAIN) ? 0 : -1;

diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h
index ae9499b80110..d82294db1295 100644
--- a/tools/perf/util/mmap.h
+++ b/tools/perf/util/mmap.h
@@ -96,7 +96,6 @@ int perf_mmap__push(struct perf_mmap *md, void *to,

size_t perf_mmap__mmap_len(struct perf_mmap *map);

-int perf_mmap__read_init(struct perf_mmap *md, bool overwrite,
- u64 *startp, u64 *endp);
+int perf_mmap__read_init(struct perf_mmap *md);
void perf_mmap__read_done(struct perf_mmap *map);
#endif /*__PERF_MMAP_H */
diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
index 4798db93e7ee..b956868fd445 100644
--- a/tools/perf/util/python.c
+++ b/tools/perf/util/python.c
@@ -984,7 +984,6 @@ static PyObject *pyrf_evlist__read_on_cpu(struct pyrf_evlist *pevlist,
int sample_id_all = 1, cpu;
static char *kwlist[] = { "cpu", "sample_id_all", NULL };
struct perf_mmap *md;
- u64 end, start;
int err;

if (!PyArg_ParseTupleAndKeywords(args, kwargs, "i|i", kwlist,
@@ -992,7 +991,7 @@ static PyObject *pyrf_evlist__read_on_cpu(struct pyrf_evlist *pevlist,
return NULL;

md = &evlist->mmap[cpu];
- if (perf_mmap__read_init(md, false, &start, &end) < 0)
+ if (perf_mmap__read_init(md) < 0)
goto end;

event = perf_mmap__read_event(md);
--
2.14.3