| Message ID | 20230517163750.997629-1-krzysztof.kozlowski@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] soundwire: qcom: fix unbalanced pm_runtime_put() | expand |
On 5/17/23 11:37, Krzysztof Kozlowski wrote: > This reverts commit 57ed510b0547 ("soundwire: qcom: use > pm_runtime_resume_and_get()") which introduced unbalanced > pm_runtime_put(), when device did not have runtime PM enabled. > > If pm_runtime_resume_and_get() failed with -EACCES, the driver continued > execution and finally called pm_runtime_put_autosuspend(). Since > pm_runtime_resume_and_get() drops the usage counter on every error, this > lead to double decrement of that counter visible in certain debugfs > actions on unattached devices (still in reset state): > > $ cat /sys/kernel/debug/soundwire/master-0-0/sdw:0:0217:f001:00:0/registers > qcom-soundwire 3210000.soundwire-controller: swrm_wait_for_wr_fifo_avail err write overflow > soundwire sdw-master-0: trf on Slave 1 failed:-5 read addr e36 count 1 > soundwire sdw:0:0217:f001:00:0: Runtime PM usage count underflow! > > Fixes: 57ed510b0547 ("soundwire: qcom: use pm_runtime_resume_and_get()") > Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Yes, this resume_and_get() added more problems indeed. One of those well-intended changes that went sideways. Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> > --- > drivers/soundwire/qcom.c | 15 +++++++++------ > 1 file changed, 9 insertions(+), 6 deletions(-) > > diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c > index aad5942e5980..f442280af9d3 100644 > --- a/drivers/soundwire/qcom.c > +++ b/drivers/soundwire/qcom.c > @@ -614,11 +614,12 @@ static irqreturn_t qcom_swrm_wake_irq_handler(int irq, void *dev_id) > struct qcom_swrm_ctrl *ctrl = dev_id; > int ret; > > - ret = pm_runtime_resume_and_get(ctrl->dev); > + ret = pm_runtime_get_sync(ctrl->dev); > if (ret < 0 && ret != -EACCES) { > dev_err_ratelimited(ctrl->dev, > - "pm_runtime_resume_and_get failed in %s, ret %d\n", > + "pm_runtime_get_sync failed in %s, ret %d\n", > __func__, ret); > + pm_runtime_put_noidle(ctrl->dev); > return ret; > } > > @@ -1197,11 +1198,12 @@ static int qcom_swrm_startup(struct snd_pcm_substream *substream, > struct snd_soc_dai *codec_dai; > int ret, i; > > - ret = pm_runtime_resume_and_get(ctrl->dev); > + ret = pm_runtime_get_sync(ctrl->dev); > if (ret < 0 && ret != -EACCES) { > dev_err_ratelimited(ctrl->dev, > - "pm_runtime_resume_and_get failed in %s, ret %d\n", > + "pm_runtime_get_sync failed in %s, ret %d\n", > __func__, ret); > + pm_runtime_put_noidle(ctrl->dev); > return ret; > } > > @@ -1402,11 +1404,12 @@ static int swrm_reg_show(struct seq_file *s_file, void *data) > struct qcom_swrm_ctrl *ctrl = s_file->private; > int reg, reg_val, ret; > > - ret = pm_runtime_resume_and_get(ctrl->dev); > + ret = pm_runtime_get_sync(ctrl->dev); > if (ret < 0 && ret != -EACCES) { > dev_err_ratelimited(ctrl->dev, > - "pm_runtime_resume_and_get failed in %s, ret %d\n", > + "pm_runtime_get_sync failed in %s, ret %d\n", > __func__, ret); > + pm_runtime_put_noidle(ctrl->dev); > return ret; > } >
On 17-05-23, 18:37, Krzysztof Kozlowski wrote: > This reverts commit 57ed510b0547 ("soundwire: qcom: use > pm_runtime_resume_and_get()") which introduced unbalanced > pm_runtime_put(), when device did not have runtime PM enabled. > > If pm_runtime_resume_and_get() failed with -EACCES, the driver continued > execution and finally called pm_runtime_put_autosuspend(). Since > pm_runtime_resume_and_get() drops the usage counter on every error, this > lead to double decrement of that counter visible in certain debugfs > actions on unattached devices (still in reset state): Applied, thanks
diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c index aad5942e5980..f442280af9d3 100644 --- a/drivers/soundwire/qcom.c +++ b/drivers/soundwire/qcom.c @@ -614,11 +614,12 @@ static irqreturn_t qcom_swrm_wake_irq_handler(int irq, void *dev_id) struct qcom_swrm_ctrl *ctrl = dev_id; int ret; - ret = pm_runtime_resume_and_get(ctrl->dev); + ret = pm_runtime_get_sync(ctrl->dev); if (ret < 0 && ret != -EACCES) { dev_err_ratelimited(ctrl->dev, - "pm_runtime_resume_and_get failed in %s, ret %d\n", + "pm_runtime_get_sync failed in %s, ret %d\n", __func__, ret); + pm_runtime_put_noidle(ctrl->dev); return ret; } @@ -1197,11 +1198,12 @@ static int qcom_swrm_startup(struct snd_pcm_substream *substream, struct snd_soc_dai *codec_dai; int ret, i; - ret = pm_runtime_resume_and_get(ctrl->dev); + ret = pm_runtime_get_sync(ctrl->dev); if (ret < 0 && ret != -EACCES) { dev_err_ratelimited(ctrl->dev, - "pm_runtime_resume_and_get failed in %s, ret %d\n", + "pm_runtime_get_sync failed in %s, ret %d\n", __func__, ret); + pm_runtime_put_noidle(ctrl->dev); return ret; } @@ -1402,11 +1404,12 @@ static int swrm_reg_show(struct seq_file *s_file, void *data) struct qcom_swrm_ctrl *ctrl = s_file->private; int reg, reg_val, ret; - ret = pm_runtime_resume_and_get(ctrl->dev); + ret = pm_runtime_get_sync(ctrl->dev); if (ret < 0 && ret != -EACCES) { dev_err_ratelimited(ctrl->dev, - "pm_runtime_resume_and_get failed in %s, ret %d\n", + "pm_runtime_get_sync failed in %s, ret %d\n", __func__, ret); + pm_runtime_put_noidle(ctrl->dev); return ret; }
This reverts commit 57ed510b0547 ("soundwire: qcom: use pm_runtime_resume_and_get()") which introduced unbalanced pm_runtime_put(), when device did not have runtime PM enabled. If pm_runtime_resume_and_get() failed with -EACCES, the driver continued execution and finally called pm_runtime_put_autosuspend(). Since pm_runtime_resume_and_get() drops the usage counter on every error, this lead to double decrement of that counter visible in certain debugfs actions on unattached devices (still in reset state): $ cat /sys/kernel/debug/soundwire/master-0-0/sdw:0:0217:f001:00:0/registers qcom-soundwire 3210000.soundwire-controller: swrm_wait_for_wr_fifo_avail err write overflow soundwire sdw-master-0: trf on Slave 1 failed:-5 read addr e36 count 1 soundwire sdw:0:0217:f001:00:0: Runtime PM usage count underflow! Fixes: 57ed510b0547 ("soundwire: qcom: use pm_runtime_resume_and_get()") Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> --- drivers/soundwire/qcom.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-)