* [PATCH v2 2/3] perf lock: Add --map-nr-entries option
2022-08-02 19:10 [PATCH v2 1/3] perf lock: Introduce struct lock_contention Namhyung Kim
@ 2022-08-02 19:10 ` Namhyung Kim
2022-08-02 19:10 ` [PATCH v2 3/3] perf lock: Print the number of lost entries for BPF Namhyung Kim
2022-08-02 21:04 ` [PATCH v2 1/3] perf lock: Introduce struct lock_contention Arnaldo Carvalho de Melo
2 siblings, 0 replies; 8+ messages in thread
From: Namhyung Kim @ 2022-08-02 19:10 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo, Jiri Olsa
Cc: Ingo Molnar, Peter Zijlstra, LKML, Ian Rogers, linux-perf-users,
Will Deacon, Waiman Long, Boqun Feng, Davidlohr Bueso, Song Liu,
Blake Jones
The --map-nr-entries option is to control number of max entries in the
perf lock contention BPF maps.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/Documentation/perf-lock.txt | 3 +++
tools/perf/builtin-lock.c | 23 ++++++++++++++++++++++-
tools/perf/util/bpf_lock_contention.c | 3 +++
tools/perf/util/lock-contention.h | 1 +
4 files changed, 29 insertions(+), 1 deletion(-)
diff --git a/tools/perf/Documentation/perf-lock.txt b/tools/perf/Documentation/perf-lock.txt
index 7949d2e6891b..193c5d8b8db9 100644
--- a/tools/perf/Documentation/perf-lock.txt
+++ b/tools/perf/Documentation/perf-lock.txt
@@ -145,6 +145,9 @@ CONTENTION OPTIONS
--tid=::
Record events on existing thread ID (comma separated list).
+--map-nr-entries::
+ Maximum number of BPF map entries (default: 10240).
+
SEE ALSO
--------
diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index eef778b7d33d..4c70cd1b9006 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -55,6 +55,7 @@ static struct rb_root thread_stats;
static bool combine_locks;
static bool show_thread_stats;
static bool use_bpf;
+static unsigned long bpf_map_entries = 10240;
static enum {
LOCK_AGGR_ADDR,
@@ -1597,6 +1598,7 @@ static int __cmd_contention(int argc, const char **argv)
struct lock_contention con = {
.target = &target,
.result = &lockhash_table[0],
+ .map_nr_entries = bpf_map_entries,
};
session = perf_session__new(use_bpf ? NULL : &data, &eops);
@@ -1786,6 +1788,24 @@ static int __cmd_record(int argc, const char **argv)
return ret;
}
+static int parse_map_entry(const struct option *opt, const char *str,
+ int unset __maybe_unused)
+{
+ unsigned long *len = (unsigned long *)opt->value;
+ unsigned long val;
+ char *endptr;
+
+ errno = 0;
+ val = strtoul(str, &endptr, 0);
+ if (*endptr != '\0' || errno != 0) {
+ pr_err("invalid BPF map length: %s\n", str);
+ return -1;
+ }
+
+ *len = val;
+ return 0;
+}
+
int cmd_lock(int argc, const char **argv)
{
const struct option lock_options[] = {
@@ -1835,9 +1855,10 @@ int cmd_lock(int argc, const char **argv)
"List of cpus to monitor"),
OPT_STRING('p', "pid", &target.pid, "pid",
"Trace on existing process id"),
- /* TODO: Add short option -t after -t/--tracer can be removed. */
OPT_STRING(0, "tid", &target.tid, "tid",
"Trace on existing thread id (exclusive to --pid)"),
+ OPT_CALLBACK(0, "map-nr-entries", &bpf_map_entries, "num",
+ "Max number of BPF map entries", parse_map_entry),
OPT_PARENT(lock_options)
};
diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c
index f5e2b4f19a72..0556cf4469ff 100644
--- a/tools/perf/util/bpf_lock_contention.c
+++ b/tools/perf/util/bpf_lock_contention.c
@@ -40,6 +40,9 @@ int lock_contention_prepare(struct lock_contention *con)
return -1;
}
+ bpf_map__set_max_entries(skel->maps.stacks, con->map_nr_entries);
+ bpf_map__set_max_entries(skel->maps.lock_stat, con->map_nr_entries);
+
if (target__has_cpu(target))
ncpus = perf_cpu_map__nr(evlist->core.user_requested_cpus);
if (target__has_task(target))
diff --git a/tools/perf/util/lock-contention.h b/tools/perf/util/lock-contention.h
index a0df5308cca4..8de8550f5ef8 100644
--- a/tools/perf/util/lock-contention.h
+++ b/tools/perf/util/lock-contention.h
@@ -112,6 +112,7 @@ struct lock_contention {
struct target *target;
struct machine *machine;
struct hlist_head *result;
+ unsigned long map_nr_entries;
};
#ifdef HAVE_BPF_SKEL
--
2.37.1.455.g008518b4e5-goog
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v2 3/3] perf lock: Print the number of lost entries for BPF
2022-08-02 19:10 [PATCH v2 1/3] perf lock: Introduce struct lock_contention Namhyung Kim
2022-08-02 19:10 ` [PATCH v2 2/3] perf lock: Add --map-nr-entries option Namhyung Kim
@ 2022-08-02 19:10 ` Namhyung Kim
2022-09-26 8:05 ` Jiri Slaby
2022-08-02 21:04 ` [PATCH v2 1/3] perf lock: Introduce struct lock_contention Arnaldo Carvalho de Melo
2 siblings, 1 reply; 8+ messages in thread
From: Namhyung Kim @ 2022-08-02 19:10 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo, Jiri Olsa
Cc: Ingo Molnar, Peter Zijlstra, LKML, Ian Rogers, linux-perf-users,
Will Deacon, Waiman Long, Boqun Feng, Davidlohr Bueso, Song Liu,
Blake Jones
Like the normal perf lock contention output, it'd print the number of
lost entries for BPF if exists or -v option is passed. Currently it
uses BROKEN_CONTENDED stat for the lost count (due to full stack maps).
$ sudo perf lock con -a -b --map-nr-entries 128 sleep 5
...
=== output for debug===
bad: 43, total: 14903
bad rate: 0.29 %
histogram of events caused bad sequence
acquire: 0
acquired: 0
contended: 43
release: 0
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/builtin-lock.c | 8 +++++++-
tools/perf/util/bpf_lock_contention.c | 6 ++++--
tools/perf/util/bpf_skel/lock_contention.bpf.c | 9 +++++++--
tools/perf/util/lock-contention.h | 1 +
4 files changed, 19 insertions(+), 5 deletions(-)
diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index 4c70cd1b9006..a8550f06cbfc 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -1471,8 +1471,11 @@ static void print_contention_result(void)
pr_info(" %10s %s\n\n", "type", "caller");
bad = total = 0;
+ if (use_bpf)
+ bad = bad_hist[BROKEN_CONTENDED];
+
while ((st = pop_from_result())) {
- total++;
+ total += use_bpf ? st->nr_contended : 1;
if (st->broken)
bad++;
@@ -1686,6 +1689,9 @@ static int __cmd_contention(int argc, const char **argv)
lock_contention_stop();
lock_contention_read(&con);
+
+ /* abuse bad hist stats for lost entries */
+ bad_hist[BROKEN_CONTENDED] = con.lost;
} else {
err = perf_session__process_events(session);
if (err)
diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c
index 0556cf4469ff..c591a66733ef 100644
--- a/tools/perf/util/bpf_lock_contention.c
+++ b/tools/perf/util/bpf_lock_contention.c
@@ -16,7 +16,7 @@ static struct lock_contention_bpf *skel;
/* should be same as bpf_skel/lock_contention.bpf.c */
struct lock_contention_key {
- u32 stack_id;
+ s32 stack_id;
};
struct lock_contention_data {
@@ -110,7 +110,7 @@ int lock_contention_stop(void)
int lock_contention_read(struct lock_contention *con)
{
int fd, stack;
- u32 prev_key, key;
+ s32 prev_key, key;
struct lock_contention_data data;
struct lock_stat *st;
struct machine *machine = con->machine;
@@ -119,6 +119,8 @@ int lock_contention_read(struct lock_contention *con)
fd = bpf_map__fd(skel->maps.lock_stat);
stack = bpf_map__fd(skel->maps.stacks);
+ con->lost = skel->bss->lost;
+
prev_key = 0;
while (!bpf_map_get_next_key(fd, &prev_key, &key)) {
struct map *kmap;
diff --git a/tools/perf/util/bpf_skel/lock_contention.bpf.c b/tools/perf/util/bpf_skel/lock_contention.bpf.c
index 67d46533e518..9e8b94eb6320 100644
--- a/tools/perf/util/bpf_skel/lock_contention.bpf.c
+++ b/tools/perf/util/bpf_skel/lock_contention.bpf.c
@@ -12,7 +12,7 @@
#define MAX_ENTRIES 10240
struct contention_key {
- __u32 stack_id;
+ __s32 stack_id;
};
struct contention_data {
@@ -27,7 +27,7 @@ struct tstamp_data {
__u64 timestamp;
__u64 lock;
__u32 flags;
- __u32 stack_id;
+ __s32 stack_id;
};
/* callstack storage */
@@ -73,6 +73,9 @@ int enabled;
int has_cpu;
int has_task;
+/* error stat */
+unsigned long lost;
+
static inline int can_record(void)
{
if (has_cpu) {
@@ -116,6 +119,8 @@ int contention_begin(u64 *ctx)
pelem->flags = (__u32)ctx[1];
pelem->stack_id = bpf_get_stackid(ctx, &stacks, BPF_F_FAST_STACK_CMP);
+ if (pelem->stack_id < 0)
+ lost++;
return 0;
}
diff --git a/tools/perf/util/lock-contention.h b/tools/perf/util/lock-contention.h
index 8de8550f5ef8..2146efc33396 100644
--- a/tools/perf/util/lock-contention.h
+++ b/tools/perf/util/lock-contention.h
@@ -113,6 +113,7 @@ struct lock_contention {
struct machine *machine;
struct hlist_head *result;
unsigned long map_nr_entries;
+ unsigned long lost;
};
#ifdef HAVE_BPF_SKEL
--
2.37.1.455.g008518b4e5-goog
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH v2 3/3] perf lock: Print the number of lost entries for BPF
2022-08-02 19:10 ` [PATCH v2 3/3] perf lock: Print the number of lost entries for BPF Namhyung Kim
@ 2022-09-26 8:05 ` Jiri Slaby
2022-09-26 21:42 ` Namhyung Kim
0 siblings, 1 reply; 8+ messages in thread
From: Jiri Slaby @ 2022-09-26 8:05 UTC (permalink / raw)
To: Namhyung Kim, Arnaldo Carvalho de Melo, Jiri Olsa
Cc: Ingo Molnar, Peter Zijlstra, LKML, Ian Rogers, linux-perf-users,
Will Deacon, Waiman Long, Boqun Feng, Davidlohr Bueso, Song Liu,
Blake Jones
Hi,
On 02. 08. 22, 21:10, Namhyung Kim wrote:
> Like the normal perf lock contention output, it'd print the number of
> lost entries for BPF if exists or -v option is passed. Currently it
> uses BROKEN_CONTENDED stat for the lost count (due to full stack maps).
...
> --- a/tools/perf/util/bpf_skel/lock_contention.bpf.c
> +++ b/tools/perf/util/bpf_skel/lock_contention.bpf.c
...
> @@ -73,6 +73,9 @@ int enabled;
> int has_cpu;
> int has_task;
>
> +/* error stat */
> +unsigned long lost;
I don't know how all this is generated into lock_contention.skel.h. But
I believe this patch breaks perf build on 32bit:
> [ 375s] In file included from util/bpf_lock_contention.c:13:
> [ 375s] util/bpf_skel/lock_contention.skel.h: In function 'lock_contention_bpf__assert':
> [ 375s] util/bpf_skel/lock_contention.skel.h:537:9: error: static assertion failed: "unexpected size of \'lost\'"
> [ 375s] 537 | _Static_assert(sizeof(s->bss->lost) == 8, "unexpected size of 'lost'");
> [ 375s] | ^~~~~~~~~~~~~~
Should the above (and below too) be __u64?
> --- a/tools/perf/util/lock-contention.h
> +++ b/tools/perf/util/lock-contention.h
> @@ -113,6 +113,7 @@ struct lock_contention {
> struct machine *machine;
> struct hlist_head *result;
> unsigned long map_nr_entries;
> + unsigned long lost;
thanks,
--
js
suse labs
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH v2 3/3] perf lock: Print the number of lost entries for BPF
2022-09-26 8:05 ` Jiri Slaby
@ 2022-09-26 21:42 ` Namhyung Kim
0 siblings, 0 replies; 8+ messages in thread
From: Namhyung Kim @ 2022-09-26 21:42 UTC (permalink / raw)
To: Jiri Slaby
Cc: Arnaldo Carvalho de Melo, Jiri Olsa, Ingo Molnar, Peter Zijlstra,
LKML, Ian Rogers, linux-perf-users, Will Deacon, Waiman Long,
Boqun Feng, Davidlohr Bueso, Song Liu, Blake Jones
Hello,
On Mon, Sep 26, 2022 at 1:05 AM Jiri Slaby <jirislaby@kernel.org> wrote:
>
> Hi,
>
> On 02. 08. 22, 21:10, Namhyung Kim wrote:
> > Like the normal perf lock contention output, it'd print the number of
> > lost entries for BPF if exists or -v option is passed. Currently it
> > uses BROKEN_CONTENDED stat for the lost count (due to full stack maps).
> ...
> > --- a/tools/perf/util/bpf_skel/lock_contention.bpf.c
> > +++ b/tools/perf/util/bpf_skel/lock_contention.bpf.c
> ...
> > @@ -73,6 +73,9 @@ int enabled;
> > int has_cpu;
> > int has_task;
> >
> > +/* error stat */
> > +unsigned long lost;
>
> I don't know how all this is generated into lock_contention.skel.h. But
> I believe this patch breaks perf build on 32bit:
> > [ 375s] In file included from util/bpf_lock_contention.c:13:
> > [ 375s] util/bpf_skel/lock_contention.skel.h: In function 'lock_contention_bpf__assert':
> > [ 375s] util/bpf_skel/lock_contention.skel.h:537:9: error: static assertion failed: "unexpected size of \'lost\'"
> > [ 375s] 537 | _Static_assert(sizeof(s->bss->lost) == 8, "unexpected size of 'lost'");
> > [ 375s] | ^~~~~~~~~~~~~~
>
> Should the above (and below too) be __u64?
Oops, it seems BPF ABI uses 8-byte long even on 32-bit systems.
Sorry for the inconvenience. Will change.
Thanks,
Namhyung
>
> > --- a/tools/perf/util/lock-contention.h
> > +++ b/tools/perf/util/lock-contention.h
> > @@ -113,6 +113,7 @@ struct lock_contention {
> > struct machine *machine;
> > struct hlist_head *result;
> > unsigned long map_nr_entries;
> > + unsigned long lost;
>
> thanks,
> --
> js
> suse labs
>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v2 1/3] perf lock: Introduce struct lock_contention
2022-08-02 19:10 [PATCH v2 1/3] perf lock: Introduce struct lock_contention Namhyung Kim
2022-08-02 19:10 ` [PATCH v2 2/3] perf lock: Add --map-nr-entries option Namhyung Kim
2022-08-02 19:10 ` [PATCH v2 3/3] perf lock: Print the number of lost entries for BPF Namhyung Kim
@ 2022-08-02 21:04 ` Arnaldo Carvalho de Melo
2022-08-02 23:47 ` Namhyung Kim
2 siblings, 1 reply; 8+ messages in thread
From: Arnaldo Carvalho de Melo @ 2022-08-02 21:04 UTC (permalink / raw)
To: Namhyung Kim
Cc: Jiri Olsa, Ingo Molnar, Peter Zijlstra, LKML, Ian Rogers,
linux-perf-users, Will Deacon, Waiman Long, Boqun Feng,
Davidlohr Bueso, Song Liu, Blake Jones
Em Tue, Aug 02, 2022 at 12:10:02PM -0700, Namhyung Kim escreveu:
> The lock_contention struct is to carry related fields together and to
> minimize the change when we add new config options.
Thanks, applied. Forgot the cover letter? :-)
- Arnaldo
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> ---
> tools/perf/builtin-lock.c | 23 ++++++++++++++---------
> tools/perf/util/bpf_lock_contention.c | 9 ++++++---
> tools/perf/util/lock-contention.h | 17 +++++++++++------
> 3 files changed, 31 insertions(+), 18 deletions(-)
>
> diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
> index 7897a33fec1b..eef778b7d33d 100644
> --- a/tools/perf/builtin-lock.c
> +++ b/tools/perf/builtin-lock.c
> @@ -1594,7 +1594,10 @@ static int __cmd_contention(int argc, const char **argv)
> .mode = PERF_DATA_MODE_READ,
> .force = force,
> };
> - struct evlist *evlist = NULL;
> + struct lock_contention con = {
> + .target = &target,
> + .result = &lockhash_table[0],
> + };
>
> session = perf_session__new(use_bpf ? NULL : &data, &eops);
> if (IS_ERR(session)) {
> @@ -1620,24 +1623,26 @@ static int __cmd_contention(int argc, const char **argv)
> signal(SIGCHLD, sighandler);
> signal(SIGTERM, sighandler);
>
> - evlist = evlist__new();
> - if (evlist == NULL) {
> + con.machine = &session->machines.host;
> +
> + con.evlist = evlist__new();
> + if (con.evlist == NULL) {
> err = -ENOMEM;
> goto out_delete;
> }
>
> - err = evlist__create_maps(evlist, &target);
> + err = evlist__create_maps(con.evlist, &target);
> if (err < 0)
> goto out_delete;
>
> if (argc) {
> - err = evlist__prepare_workload(evlist, &target,
> + err = evlist__prepare_workload(con.evlist, &target,
> argv, false, NULL);
> if (err < 0)
> goto out_delete;
> }
>
> - if (lock_contention_prepare(evlist, &target) < 0) {
> + if (lock_contention_prepare(&con) < 0) {
> pr_err("lock contention BPF setup failed\n");
> goto out_delete;
> }
> @@ -1672,13 +1677,13 @@ static int __cmd_contention(int argc, const char **argv)
> if (use_bpf) {
> lock_contention_start();
> if (argc)
> - evlist__start_workload(evlist);
> + evlist__start_workload(con.evlist);
>
> /* wait for signal */
> pause();
>
> lock_contention_stop();
> - lock_contention_read(&session->machines.host, &lockhash_table[0]);
> + lock_contention_read(&con);
> } else {
> err = perf_session__process_events(session);
> if (err)
> @@ -1691,7 +1696,7 @@ static int __cmd_contention(int argc, const char **argv)
> print_contention_result();
>
> out_delete:
> - evlist__delete(evlist);
> + evlist__delete(con.evlist);
> lock_contention_finish();
> perf_session__delete(session);
> return err;
> diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c
> index 16b7451b4b09..f5e2b4f19a72 100644
> --- a/tools/perf/util/bpf_lock_contention.c
> +++ b/tools/perf/util/bpf_lock_contention.c
> @@ -27,10 +27,12 @@ struct lock_contention_data {
> u32 flags;
> };
>
> -int lock_contention_prepare(struct evlist *evlist, struct target *target)
> +int lock_contention_prepare(struct lock_contention *con)
> {
> int i, fd;
> int ncpus = 1, ntasks = 1;
> + struct evlist *evlist = con->evlist;
> + struct target *target = con->target;
>
> skel = lock_contention_bpf__open();
> if (!skel) {
> @@ -102,12 +104,13 @@ int lock_contention_stop(void)
> return 0;
> }
>
> -int lock_contention_read(struct machine *machine, struct hlist_head *head)
> +int lock_contention_read(struct lock_contention *con)
> {
> int fd, stack;
> u32 prev_key, key;
> struct lock_contention_data data;
> struct lock_stat *st;
> + struct machine *machine = con->machine;
> u64 stack_trace[CONTENTION_STACK_DEPTH];
>
> fd = bpf_map__fd(skel->maps.lock_stat);
> @@ -163,7 +166,7 @@ int lock_contention_read(struct machine *machine, struct hlist_head *head)
> return -1;
> }
>
> - hlist_add_head(&st->hash_entry, head);
> + hlist_add_head(&st->hash_entry, con->result);
> prev_key = key;
> }
>
> diff --git a/tools/perf/util/lock-contention.h b/tools/perf/util/lock-contention.h
> index 092c84441f9f..a0df5308cca4 100644
> --- a/tools/perf/util/lock-contention.h
> +++ b/tools/perf/util/lock-contention.h
> @@ -107,18 +107,24 @@ struct evlist;
> struct machine;
> struct target;
>
> +struct lock_contention {
> + struct evlist *evlist;
> + struct target *target;
> + struct machine *machine;
> + struct hlist_head *result;
> +};
> +
> #ifdef HAVE_BPF_SKEL
>
> -int lock_contention_prepare(struct evlist *evlist, struct target *target);
> +int lock_contention_prepare(struct lock_contention *con);
> int lock_contention_start(void);
> int lock_contention_stop(void);
> -int lock_contention_read(struct machine *machine, struct hlist_head *head);
> +int lock_contention_read(struct lock_contention *con);
> int lock_contention_finish(void);
>
> #else /* !HAVE_BPF_SKEL */
>
> -static inline int lock_contention_prepare(struct evlist *evlist __maybe_unused,
> - struct target *target __maybe_unused)
> +static inline int lock_contention_prepare(struct lock_contention *con __maybe_unused)
> {
> return 0;
> }
> @@ -127,8 +133,7 @@ static inline int lock_contention_start(void) { return 0; }
> static inline int lock_contention_stop(void) { return 0; }
> static inline int lock_contention_finish(void) { return 0; }
>
> -static inline int lock_contention_read(struct machine *machine __maybe_unused,
> - struct hlist_head *head __maybe_unused)
> +static inline int lock_contention_read(struct lock_contention *con __maybe_unused)
> {
> return 0;
> }
> --
> 2.37.1.455.g008518b4e5-goog
--
- Arnaldo
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH v2 1/3] perf lock: Introduce struct lock_contention
2022-08-02 21:04 ` [PATCH v2 1/3] perf lock: Introduce struct lock_contention Arnaldo Carvalho de Melo
@ 2022-08-02 23:47 ` Namhyung Kim
2022-08-03 15:12 ` Arnaldo Carvalho de Melo
0 siblings, 1 reply; 8+ messages in thread
From: Namhyung Kim @ 2022-08-02 23:47 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo
Cc: Jiri Olsa, Ingo Molnar, Peter Zijlstra, LKML, Ian Rogers,
linux-perf-users, Will Deacon, Waiman Long, Boqun Feng,
Davidlohr Bueso, Song Liu, Blake Jones
On Tue, Aug 2, 2022 at 2:04 PM Arnaldo Carvalho de Melo <acme@kernel.org> wrote:
>
> Em Tue, Aug 02, 2022 at 12:10:02PM -0700, Namhyung Kim escreveu:
> > The lock_contention struct is to carry related fields together and to
> > minimize the change when we add new config options.
>
>
> Thanks, applied. Forgot the cover letter? :-)
Thank you!
I thought it's a small change that doesn't require a cover letter.
But if you prefer seeing it for small changes too, I'd write a
short letter next time.
Thanks,
Namhyung
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v2 1/3] perf lock: Introduce struct lock_contention
2022-08-02 23:47 ` Namhyung Kim
@ 2022-08-03 15:12 ` Arnaldo Carvalho de Melo
0 siblings, 0 replies; 8+ messages in thread
From: Arnaldo Carvalho de Melo @ 2022-08-03 15:12 UTC (permalink / raw)
To: Namhyung Kim
Cc: Jiri Olsa, Ingo Molnar, Peter Zijlstra, LKML, Ian Rogers,
linux-perf-users, Will Deacon, Waiman Long, Boqun Feng,
Davidlohr Bueso, Song Liu, Blake Jones
Em Tue, Aug 02, 2022 at 04:47:02PM -0700, Namhyung Kim escreveu:
> On Tue, Aug 2, 2022 at 2:04 PM Arnaldo Carvalho de Melo <acme@kernel.org> wrote:
> >
> > Em Tue, Aug 02, 2022 at 12:10:02PM -0700, Namhyung Kim escreveu:
> > > The lock_contention struct is to carry related fields together and to
> > > minimize the change when we add new config options.
> >
> >
> > Thanks, applied. Forgot the cover letter? :-)
>
> Thank you!
>
> I thought it's a small change that doesn't require a cover letter.
> But if you prefer seeing it for small changes too, I'd write a
> short letter next time.
Yeah, just felt unusual, but then, b4 with any of the message-ids works
just fine, so up to you, I'm adjusting.
- Arnaldo
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