When dummy tracking go system wide, the mmap cpu mask is changed.
Therefore, needs to be placed before record__init_thread_masks().
Dummy tracking has been set in record__open(), move it before
record__init_thread_masks() and add a helper for unified processing.
The sys_perf_event_open invoked is as follows:
# perf --debug verbose=3 record -e cpu-clock -D 100 true
<SNIP>
Opening: cpu-clock
------------------------------------------------------------
perf_event_attr:
type 1 (PERF_TYPE_SOFTWARE)
size 136
config 0 (PERF_COUNT_SW_CPU_CLOCK)
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|PERIOD|IDENTIFIER
read_format ID|LOST
disabled 1
inherit 1
freq 1
sample_id_all 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid 10318 cpu 0 group_fd -1 flags 0x8 = 5
sys_perf_event_open: pid 10318 cpu 1 group_fd -1 flags 0x8 = 6
sys_perf_event_open: pid 10318 cpu 2 group_fd -1 flags 0x8 = 7
sys_perf_event_open: pid 10318 cpu 3 group_fd -1 flags 0x8 = 9
sys_perf_event_open: pid 10318 cpu 4 group_fd -1 flags 0x8 = 10
sys_perf_event_open: pid 10318 cpu 5 group_fd -1 flags 0x8 = 11
sys_perf_event_open: pid 10318 cpu 6 group_fd -1 flags 0x8 = 12
sys_perf_event_open: pid 10318 cpu 7 group_fd -1 flags 0x8 = 13
Opening: dummy:u
------------------------------------------------------------
perf_event_attr:
type 1 (PERF_TYPE_SOFTWARE)
size 136
config 0x9 (PERF_COUNT_SW_DUMMY)
{ sample_period, sample_freq } 1
sample_type IP|TID|TIME|IDENTIFIER
read_format ID|LOST
disabled 1
inherit 1
exclude_kernel 1
exclude_hv 1
mmap 1
comm 1
enable_on_exec 1
task 1
sample_id_all 1
exclude_guest 1
mmap2 1
comm_exec 1
ksymbol 1
bpf_event 1
------------------------------------------------------------
sys_perf_event_open: pid 10318 cpu 0 group_fd -1 flags 0x8 = 14
sys_perf_event_open: pid 10318 cpu 1 group_fd -1 flags 0x8 = 15
sys_perf_event_open: pid 10318 cpu 2 group_fd -1 flags 0x8 = 16
sys_perf_event_open: pid 10318 cpu 3 group_fd -1 flags 0x8 = 17
sys_perf_event_open: pid 10318 cpu 4 group_fd -1 flags 0x8 = 18
sys_perf_event_open: pid 10318 cpu 5 group_fd -1 flags 0x8 = 19
sys_perf_event_open: pid 10318 cpu 6 group_fd -1 flags 0x8 = 20
sys_perf_event_open: pid 10318 cpu 7 group_fd -1 flags 0x8 = 21
<SNIP>
Signed-off-by: Yang Jihong <[email protected]>
---
tools/perf/builtin-record.c | 59 +++++++++++++++++++++++--------------
1 file changed, 37 insertions(+), 22 deletions(-)
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index ca83599cc50c..3ff9d972225e 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -908,6 +908,37 @@ static int record__config_off_cpu(struct record *rec)
return off_cpu_prepare(rec->evlist, &rec->opts.target, &rec->opts);
}
+static int record__config_tracking_events(struct record *rec)
+{
+ struct record_opts *opts = &rec->opts;
+ struct evlist *evlist = rec->evlist;
+ struct evsel *evsel;
+
+ /*
+ * For initial_delay, system wide or a hybrid system, we need to add a
+ * dummy event so that we can track PERF_RECORD_MMAP to cover the delay
+ * of waiting or event synthesis.
+ */
+ if (opts->target.initial_delay || target__has_cpu(&opts->target) ||
+ perf_pmus__num_core_pmus() > 1) {
+ evsel = evlist__findnew_tracking_event(evlist, false);
+ if (!evsel)
+ return -ENOMEM;
+
+ /*
+ * Enable the dummy event when the process is forked for
+ * initial_delay, immediately for system wide.
+ */
+ if (opts->target.initial_delay && !evsel->immediate &&
+ !target__has_cpu(&opts->target))
+ evsel->core.attr.enable_on_exec = 1;
+ else
+ evsel->immediate = 1;
+ }
+
+ return 0;
+}
+
static bool record__kcore_readable(struct machine *machine)
{
char kcore[PATH_MAX];
@@ -1288,28 +1319,6 @@ static int record__open(struct record *rec)
struct record_opts *opts = &rec->opts;
int rc = 0;
- /*
- * For initial_delay, system wide or a hybrid system, we need to add a
- * dummy event so that we can track PERF_RECORD_MMAP to cover the delay
- * of waiting or event synthesis.
- */
- if (opts->target.initial_delay || target__has_cpu(&opts->target) ||
- perf_pmus__num_core_pmus() > 1) {
- pos = evlist__findnew_tracking_event(evlist, false);
- if (!pos)
- return -ENOMEM;
-
- /*
- * Enable the dummy event when the process is forked for
- * initial_delay, immediately for system wide.
- */
- if (opts->target.initial_delay && !pos->immediate &&
- !target__has_cpu(&opts->target))
- pos->core.attr.enable_on_exec = 1;
- else
- pos->immediate = 1;
- }
-
evlist__config(evlist, opts, &callchain_param);
evlist__for_each_entry(evlist, pos) {
@@ -4235,6 +4244,12 @@ int cmd_record(int argc, const char **argv)
goto out;
}
+ err = record__config_tracking_events(rec);
+ if (err) {
+ pr_err("record__config_tracking_events failed, error %d\n", err);
+ goto out;
+ }
+
err = record__init_thread_masks(rec);
if (err) {
pr_err("Failed to initialize parallel data streaming masks\n");
--
2.30.GIT
On 4/08/23 05:07, Yang Jihong wrote:
> When dummy tracking go system wide, the mmap cpu mask is changed.
> Therefore, needs to be placed before record__init_thread_masks().
> Dummy tracking has been set in record__open(), move it before
> record__init_thread_masks() and add a helper for unified processing.
>
> The sys_perf_event_open invoked is as follows:
>
> # perf --debug verbose=3 record -e cpu-clock -D 100 true
> <SNIP>
> Opening: cpu-clock
> ------------------------------------------------------------
> perf_event_attr:
> type 1 (PERF_TYPE_SOFTWARE)
> size 136
> config 0 (PERF_COUNT_SW_CPU_CLOCK)
> { sample_period, sample_freq } 4000
> sample_type IP|TID|TIME|PERIOD|IDENTIFIER
> read_format ID|LOST
> disabled 1
> inherit 1
> freq 1
> sample_id_all 1
> exclude_guest 1
> ------------------------------------------------------------
> sys_perf_event_open: pid 10318 cpu 0 group_fd -1 flags 0x8 = 5
> sys_perf_event_open: pid 10318 cpu 1 group_fd -1 flags 0x8 = 6
> sys_perf_event_open: pid 10318 cpu 2 group_fd -1 flags 0x8 = 7
> sys_perf_event_open: pid 10318 cpu 3 group_fd -1 flags 0x8 = 9
> sys_perf_event_open: pid 10318 cpu 4 group_fd -1 flags 0x8 = 10
> sys_perf_event_open: pid 10318 cpu 5 group_fd -1 flags 0x8 = 11
> sys_perf_event_open: pid 10318 cpu 6 group_fd -1 flags 0x8 = 12
> sys_perf_event_open: pid 10318 cpu 7 group_fd -1 flags 0x8 = 13
> Opening: dummy:u
> ------------------------------------------------------------
> perf_event_attr:
> type 1 (PERF_TYPE_SOFTWARE)
> size 136
> config 0x9 (PERF_COUNT_SW_DUMMY)
> { sample_period, sample_freq } 1
> sample_type IP|TID|TIME|IDENTIFIER
> read_format ID|LOST
> disabled 1
> inherit 1
> exclude_kernel 1
> exclude_hv 1
> mmap 1
> comm 1
> enable_on_exec 1
> task 1
> sample_id_all 1
> exclude_guest 1
> mmap2 1
> comm_exec 1
> ksymbol 1
> bpf_event 1
> ------------------------------------------------------------
> sys_perf_event_open: pid 10318 cpu 0 group_fd -1 flags 0x8 = 14
> sys_perf_event_open: pid 10318 cpu 1 group_fd -1 flags 0x8 = 15
> sys_perf_event_open: pid 10318 cpu 2 group_fd -1 flags 0x8 = 16
> sys_perf_event_open: pid 10318 cpu 3 group_fd -1 flags 0x8 = 17
> sys_perf_event_open: pid 10318 cpu 4 group_fd -1 flags 0x8 = 18
> sys_perf_event_open: pid 10318 cpu 5 group_fd -1 flags 0x8 = 19
> sys_perf_event_open: pid 10318 cpu 6 group_fd -1 flags 0x8 = 20
> sys_perf_event_open: pid 10318 cpu 7 group_fd -1 flags 0x8 = 21
> <SNIP>
>
> Signed-off-by: Yang Jihong <[email protected]>
Acked-by: Adrian Hunter <[email protected]>
> ---
> tools/perf/builtin-record.c | 59 +++++++++++++++++++++++--------------
> 1 file changed, 37 insertions(+), 22 deletions(-)
>
> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> index ca83599cc50c..3ff9d972225e 100644
> --- a/tools/perf/builtin-record.c
> +++ b/tools/perf/builtin-record.c
> @@ -908,6 +908,37 @@ static int record__config_off_cpu(struct record *rec)
> return off_cpu_prepare(rec->evlist, &rec->opts.target, &rec->opts);
> }
>
> +static int record__config_tracking_events(struct record *rec)
> +{
> + struct record_opts *opts = &rec->opts;
> + struct evlist *evlist = rec->evlist;
> + struct evsel *evsel;
> +
> + /*
> + * For initial_delay, system wide or a hybrid system, we need to add a
> + * dummy event so that we can track PERF_RECORD_MMAP to cover the delay
> + * of waiting or event synthesis.
> + */
> + if (opts->target.initial_delay || target__has_cpu(&opts->target) ||
> + perf_pmus__num_core_pmus() > 1) {
> + evsel = evlist__findnew_tracking_event(evlist, false);
> + if (!evsel)
> + return -ENOMEM;
> +
> + /*
> + * Enable the dummy event when the process is forked for
> + * initial_delay, immediately for system wide.
> + */
> + if (opts->target.initial_delay && !evsel->immediate &&
> + !target__has_cpu(&opts->target))
> + evsel->core.attr.enable_on_exec = 1;
> + else
> + evsel->immediate = 1;
> + }
> +
> + return 0;
> +}
> +
> static bool record__kcore_readable(struct machine *machine)
> {
> char kcore[PATH_MAX];
> @@ -1288,28 +1319,6 @@ static int record__open(struct record *rec)
> struct record_opts *opts = &rec->opts;
> int rc = 0;
>
> - /*
> - * For initial_delay, system wide or a hybrid system, we need to add a
> - * dummy event so that we can track PERF_RECORD_MMAP to cover the delay
> - * of waiting or event synthesis.
> - */
> - if (opts->target.initial_delay || target__has_cpu(&opts->target) ||
> - perf_pmus__num_core_pmus() > 1) {
> - pos = evlist__findnew_tracking_event(evlist, false);
> - if (!pos)
> - return -ENOMEM;
> -
> - /*
> - * Enable the dummy event when the process is forked for
> - * initial_delay, immediately for system wide.
> - */
> - if (opts->target.initial_delay && !pos->immediate &&
> - !target__has_cpu(&opts->target))
> - pos->core.attr.enable_on_exec = 1;
> - else
> - pos->immediate = 1;
> - }
> -
> evlist__config(evlist, opts, &callchain_param);
>
> evlist__for_each_entry(evlist, pos) {
> @@ -4235,6 +4244,12 @@ int cmd_record(int argc, const char **argv)
> goto out;
> }
>
> + err = record__config_tracking_events(rec);
> + if (err) {
> + pr_err("record__config_tracking_events failed, error %d\n", err);
> + goto out;
> + }
> +
> err = record__init_thread_masks(rec);
> if (err) {
> pr_err("Failed to initialize parallel data streaming masks\n");
Hello,
On 2023/8/15 4:29, Ian Rogers wrote:
> On Thu, Aug 3, 2023 at 11:58 PM Adrian Hunter <[email protected]> wrote:
>>
>> On 4/08/23 05:07, Yang Jihong wrote:
>>> When dummy tracking go system wide, the mmap cpu mask is changed.
>
> As previously commented, can we improve the quality of the function
> names and commit messages? This sentence is particularly difficult to
> understand, I don't understand it.
OK. The commit messages will be modified. Please check whether the
following description is clear:
User space tasks can migrate between CPUs, so when tracing selected
CPUs, sideband for all CPUs is needed. In this case set the cpu map of
the evsel to all online CPUs. This may modify the original cpu map of
the evlist.
Therefore, need to check whether the preceding scenario exists before
record__init_thread_masks().
Dummy tracking has been set in record__open(), move it before
record__init_thread_masks() and add a helper for unified processing.
Thanks,
Yang
Hello,
On 2023/8/15 9:57, Yang Jihong wrote:
> Hello,
>
> On 2023/8/15 4:29, Ian Rogers wrote:
>> On Thu, Aug 3, 2023 at 11:58 PM Adrian Hunter
>> <[email protected]> wrote:
>>>
>>> On 4/08/23 05:07, Yang Jihong wrote:
>>>> When dummy tracking go system wide, the mmap cpu mask is changed.
>>
>> As previously commented, can we improve the quality of the function
>> names and commit messages? This sentence is particularly difficult to
>> understand, I don't understand it.
>
> OK. The commit messages will be modified. Please check whether the
> following description is clear:
>
> User space tasks can migrate between CPUs, so when tracing selected
> CPUs, sideband for all CPUs is needed. In this case set the cpu map of
> the evsel to all online CPUs. This may modify the original cpu map of
> the evlist.
> Therefore, need to check whether the preceding scenario exists before
> record__init_thread_masks().
> Dummy tracking has been set in record__open(), move it before
> record__init_thread_masks() and add a helper for unified processing.
>
Ian, do you have any questions about the commit message above? If it's
okay, I'll send the next version as above.
Thanks,
Yang