[PATCH 6.8 626/715] hwtracing: hisi_ptt: Move type check to the beginning of hisi_ptt_pmu_event_init()

From: Sasha Levin
Date: Sun Mar 24 2024 - 20:55:11 EST


From: Yang Jihong <yangjihong1@xxxxxxxxxx>

[ Upstream commit 06226d120a28f146abd3637799958a4dc4dbb7a1 ]

When perf_init_event() calls perf_try_init_event() to init pmu driver,
searches for the next pmu driver only when the return value is -ENOENT.
Therefore, hisi_ptt_pmu_event_init() needs to check the type at the
beginning of the function.
Otherwise, in the case of perf-task mode, perf_try_init_event() returns
-EOPNOTSUPP and skips subsequent pmu drivers, causes perf_init_event() to
fail.

Fixes: ff0de066b463 ("hwtracing: hisi_ptt: Add trace function support for HiSilicon PCIe Tune and Trace device")
Signed-off-by: Yang Jihong <yangjihong1@xxxxxxxxxx>
Reviewed-by: Yicong Yang <yangyicong@xxxxxxxxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Link: https://lore.kernel.org/r/20240108121906.3514820-1-yangjihong1@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/hwtracing/ptt/hisi_ptt.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
index c1b5fd2b89741..4bf04a9778407 100644
--- a/drivers/hwtracing/ptt/hisi_ptt.c
+++ b/drivers/hwtracing/ptt/hisi_ptt.c
@@ -998,6 +998,9 @@ static int hisi_ptt_pmu_event_init(struct perf_event *event)
int ret;
u32 val;

+ if (event->attr.type != hisi_ptt->hisi_ptt_pmu.type)
+ return -ENOENT;
+
if (event->cpu < 0) {
dev_dbg(event->pmu->dev, "Per-task mode not supported\n");
return -EOPNOTSUPP;
@@ -1006,9 +1009,6 @@ static int hisi_ptt_pmu_event_init(struct perf_event *event)
if (event->attach_state & PERF_ATTACH_TASK)
return -EOPNOTSUPP;

- if (event->attr.type != hisi_ptt->hisi_ptt_pmu.type)
- return -ENOENT;
-
ret = hisi_ptt_trace_valid_filter(hisi_ptt, event->attr.config);
if (ret < 0)
return ret;
--
2.43.0