[PATCH stable 6.6 and 6.7 1/2] perf top: Use evsel's cpus to replace user_requested_cpus

[PATCH stable 6.6 and 6.7 1/2] perf top: Use evsel's cpus to replace user_requested_cpus

[kan.liang]

From: Kan Liang <kan.liang@linux.intel.com>

[The patch set is to fix the perf top failure on all Intel hybrid
machines. Without the patch, the default perf top command is broken.

I have verified that the patches on both stable 6.6 and 6.7. They can
be applied to stable 6.6 and 6.7 tree without any modification as well.

Please consider to apply them to stable 6.6 and 6.7. Thanks]

------------------

From: Kan Liang <kan.liang@linux.intel.com>

[ Upstream commit 5fa695e7da4975e8d21ce49f3718d6cf00ecb75e ]

perf top errors out on a hybrid machine
 $perf top

 Error:
 The cycles:P event is not supported.

The perf top expects that the "cycles" is collected on all CPUs in the
system. But for hybrid there is no single "cycles" event which can cover
all CPUs. Perf has to split it into two cycles events, e.g.,
cpu_core/cycles/ and cpu_atom/cycles/. Each event has its own CPU mask.
If a event is opened on the unsupported CPU. The open fails. That's the
reason of the above error out.

Perf should only open the cycles event on the corresponding CPU. The
commit ef91871c960e ("perf evlist: Propagate user CPU maps intersecting
core PMU maps") intersect the requested CPU map with the CPU map of the
PMU. Use the evsel's cpus to replace user_requested_cpus.

The evlist's threads are also propagated to the evsel's threads in
__perf_evlist__propagate_maps(). For a system-wide event, perf appends
a dummy event and assign it to the evsel's threads. For a per-thread
event, the evlist's thread_map is assigned to the evsel's threads. The
same as the other tools, e.g., perf record, using the evsel's threads
when opening an event.

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Hector Martin <marcan@marcan.st>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Closes: https://lore.kernel.org/linux-perf-users/ZXNnDrGKXbEELMXV@kernel.org/
Link: https://lore.kernel.org/r/20231214144612.1092028-1-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-top.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index ea8c7eca5eee..cce9350177e2 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -1027,8 +1027,8 @@ static int perf_top__start_counters(struct perf_top *top)
 
 	evlist__for_each_entry(evlist, counter) {
 try_again:
-		if (evsel__open(counter, top->evlist->core.user_requested_cpus,
-				     top->evlist->core.threads) < 0) {
+		if (evsel__open(counter, counter->core.cpus,
+				counter->core.threads) < 0) {
 
 			/*
 			 * Specially handle overwrite fall back.
-- 
2.34.1

[PATCH stable 6.6 and 6.7 2/2] perf top: Uniform the event name for the hybrid machine

[kan.liang]

From: Kan Liang <kan.liang@linux.intel.com>

[The patch set is to fix the perf top failure on all Intel hybrid
machines. Without the patch, the default perf top command is broken.

I have verified that the patches on both stable 6.6 and 6.7. They can
be applied to stable 6.6 and 6.7 tree without any modification as well.

Please consider to apply them to stable 6.6 and 6.7. Thanks]

------------------

From: Kan Liang <kan.liang@linux.intel.com>

[ Upstream commit a61f89bf76ef6f87ec48dd90dbc73a6cf9952edc ]

It's hard to distinguish the default cycles events among hybrid PMUs.
For example,

  $ perf top
  Available samples
  385 cycles:P
  903 cycles:P

The other tool, e.g., perf record, uniforms the event name and adds the
hybrid PMU name before opening the event. So the events can be easily
distinguished. Apply the same methodology for the perf top as well.

The evlist__uniquify_name() will be invoked by both record and top.
Move it to util/evlist.c

With the patch:

  $ perf top
  Available samples
  148 cpu_atom/cycles:P/
  1K cpu_core/cycles:P/

Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Hector Martin <marcan@marcan.st>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20231214144612.1092028-2-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-record.c | 28 +---------------------------
 tools/perf/builtin-top.c    |  1 +
 tools/perf/util/evlist.c    | 25 +++++++++++++++++++++++++
 tools/perf/util/evlist.h    |  1 +
 4 files changed, 28 insertions(+), 27 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 34bb31f08bb5..ad0e4dbe4e86 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -2184,32 +2184,6 @@ static void hit_auxtrace_snapshot_trigger(struct record *rec)
 	}
 }
 
-static void record__uniquify_name(struct record *rec)
-{
-	struct evsel *pos;
-	struct evlist *evlist = rec->evlist;
-	char *new_name;
-	int ret;
-
-	if (perf_pmus__num_core_pmus() == 1)
-		return;
-
-	evlist__for_each_entry(evlist, pos) {
-		if (!evsel__is_hybrid(pos))
-			continue;
-
-		if (strchr(pos->name, '/'))
-			continue;
-
-		ret = asprintf(&new_name, "%s/%s/",
-			       pos->pmu_name, pos->name);
-		if (ret) {
-			free(pos->name);
-			pos->name = new_name;
-		}
-	}
-}
-
 static int record__terminate_thread(struct record_thread *thread_data)
 {
 	int err;
@@ -2443,7 +2417,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
 	if (data->is_pipe && rec->evlist->core.nr_entries == 1)
 		rec->opts.sample_id = true;
 
-	record__uniquify_name(rec);
+	evlist__uniquify_name(rec->evlist);
 
 	/* Debug message used by test scripts */
 	pr_debug3("perf record opening and mmapping events\n");
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index cce9350177e2..cd64ae44ccbd 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -1299,6 +1299,7 @@ static int __cmd_top(struct perf_top *top)
 		}
 	}
 
+	evlist__uniquify_name(top->evlist);
 	ret = perf_top__start_counters(top);
 	if (ret)
 		return ret;
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 8a8fe1fa0d38..8bf537a29809 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -2507,3 +2507,28 @@ void evlist__warn_user_requested_cpus(struct evlist *evlist, const char *cpu_lis
 	}
 	perf_cpu_map__put(user_requested_cpus);
 }
+
+void evlist__uniquify_name(struct evlist *evlist)
+{
+	struct evsel *pos;
+	char *new_name;
+	int ret;
+
+	if (perf_pmus__num_core_pmus() == 1)
+		return;
+
+	evlist__for_each_entry(evlist, pos) {
+		if (!evsel__is_hybrid(pos))
+			continue;
+
+		if (strchr(pos->name, '/'))
+			continue;
+
+		ret = asprintf(&new_name, "%s/%s/",
+			       pos->pmu_name, pos->name);
+		if (ret) {
+			free(pos->name);
+			pos->name = new_name;
+		}
+	}
+}
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 664c6bf7b3e0..d63486261fd2 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -441,5 +441,6 @@ struct evsel *evlist__find_evsel(struct evlist *evlist, int idx);
 int evlist__scnprintf_evsels(struct evlist *evlist, size_t size, char *bf);
 void evlist__check_mem_load_aux(struct evlist *evlist);
 void evlist__warn_user_requested_cpus(struct evlist *evlist, const char *cpu_list);
+void evlist__uniquify_name(struct evlist *evlist);
 
 #endif /* __PERF_EVLIST_H */
-- 
2.34.1

Re: [PATCH stable 6.6 and 6.7 2/2] perf top: Uniform the event name for the hybrid machine

[Greg KH]

On Fri, Mar 08, 2024 at 07:12:39AM -0800, kan.liang@linux.intel.com wrote:
> From: Kan Liang <kan.liang@linux.intel.com>
> 
> [The patch set is to fix the perf top failure on all Intel hybrid
> machines. Without the patch, the default perf top command is broken.
> 
> I have verified that the patches on both stable 6.6 and 6.7. They can
> be applied to stable 6.6 and 6.7 tree without any modification as well.
> 
> Please consider to apply them to stable 6.6 and 6.7. Thanks]

Already in the 6.6.23 and 6.7.11 releases.

thanks,

greg k-h

Re: [PATCH stable 6.6 and 6.7 2/2] perf top: Uniform the event name for the hybrid machine

[Liang, Kan]

Hi Greg,

On 2024-03-29 9:09 a.m., Greg KH wrote:
> On Fri, Mar 08, 2024 at 07:12:39AM -0800, kan.liang@linux.intel.com wrote:
>> From: Kan Liang <kan.liang@linux.intel.com>
>>
>> [The patch set is to fix the perf top failure on all Intel hybrid
>> machines. Without the patch, the default perf top command is broken.
>>
>> I have verified that the patches on both stable 6.6 and 6.7. They can
>> be applied to stable 6.6 and 6.7 tree without any modification as well.
>>
>> Please consider to apply them to stable 6.6 and 6.7. Thanks]
> 
> Already in the 6.6.23 and 6.7.11 releases.
> 

Thanks. I see this one (2/2) is merged.
Could you please also apply the first patch (1/2) as well? Without the
first one, the perf top still fails.

Thanks,
Kan

> thanks,
> 
> greg k-h

Re: [PATCH stable 6.6 and 6.7 2/2] perf top: Uniform the event name for the hybrid machine

[Greg KH]

On Fri, Mar 29, 2024 at 09:16:09AM -0400, Liang, Kan wrote:
> Hi Greg,
> 
> On 2024-03-29 9:09 a.m., Greg KH wrote:
> > On Fri, Mar 08, 2024 at 07:12:39AM -0800, kan.liang@linux.intel.com wrote:
> >> From: Kan Liang <kan.liang@linux.intel.com>
> >>
> >> [The patch set is to fix the perf top failure on all Intel hybrid
> >> machines. Without the patch, the default perf top command is broken.
> >>
> >> I have verified that the patches on both stable 6.6 and 6.7. They can
> >> be applied to stable 6.6 and 6.7 tree without any modification as well.
> >>
> >> Please consider to apply them to stable 6.6 and 6.7. Thanks]
> > 
> > Already in the 6.6.23 and 6.7.11 releases.
> > 
> 
> Thanks. I see this one (2/2) is merged.
> Could you please also apply the first patch (1/2) as well? Without the
> first one, the perf top still fails.

Already done, thanks.