[PATCH 5.7 144/393] drm/panfrost: Fix inbalance of devfreq record_busy/idle()

From: Greg Kroah-Hartman
Date: Mon Aug 17 2020 - 15:02:08 EST


From: Steven Price <steven.price@xxxxxxx>

[ Upstream commit b99773ef258e628bd53cab22d450a755b73b4d55 ]

The calls to panfrost_devfreq_record_busy() and
panfrost_devfreq_record_idle() must be balanced to ensure that the
devfreq utilisation is correctly reported. But there are two cases where
this doesn't work correctly.

In panfrost_job_hw_submit() if pm_runtime_get_sync() fails or the
WARN_ON() fires then no call to panfrost_devfreq_record_busy() is made,
but when the job times out the corresponding _record_idle() call is
still made in panfrost_job_timedout(). Move the call up to ensure that
it always happens.

Secondly panfrost_job_timedout() only makes a single call to
panfrost_devfreq_record_idle() even if it is cleaning up multiple jobs.
Move the call inside the loop to ensure that the number of
_record_idle() calls matches the number of _record_busy() calls.

Fixes: 9e62b885f715 ("drm/panfrost: Simplify devfreq utilisation tracking")
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@xxxxxxxxxxxxx>
Signed-off-by: Steven Price <steven.price@xxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20200522153653.40754-1-steven.price@xxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/panfrost/panfrost_job.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
index 7914b15708412..f9519afca29d9 100644
--- a/drivers/gpu/drm/panfrost/panfrost_job.c
+++ b/drivers/gpu/drm/panfrost/panfrost_job.c
@@ -145,6 +145,8 @@ static void panfrost_job_hw_submit(struct panfrost_job *job, int js)
u64 jc_head = job->jc;
int ret;

+ panfrost_devfreq_record_busy(pfdev);
+
ret = pm_runtime_get_sync(pfdev->dev);
if (ret < 0)
return;
@@ -155,7 +157,6 @@ static void panfrost_job_hw_submit(struct panfrost_job *job, int js)
}

cfg = panfrost_mmu_as_get(pfdev, &job->file_priv->mmu);
- panfrost_devfreq_record_busy(pfdev);

job_write(pfdev, JS_HEAD_NEXT_LO(js), jc_head & 0xFFFFFFFF);
job_write(pfdev, JS_HEAD_NEXT_HI(js), jc_head >> 32);
@@ -410,12 +411,12 @@ static void panfrost_job_timedout(struct drm_sched_job *sched_job)
for (i = 0; i < NUM_JOB_SLOTS; i++) {
if (pfdev->jobs[i]) {
pm_runtime_put_noidle(pfdev->dev);
+ panfrost_devfreq_record_idle(pfdev);
pfdev->jobs[i] = NULL;
}
}
spin_unlock_irqrestore(&pfdev->js->job_lock, flags);

- panfrost_devfreq_record_idle(pfdev);
panfrost_device_reset(pfdev);

for (i = 0; i < NUM_JOB_SLOTS; i++)
--
2.25.1