| Message ID | 1543358591-25189-1-git-send-email-thara.gopinath@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [V2] thermal: Fix locking in cooling device sysfs update cur_state | expand |
On 11/27/2018 05:43 PM, Thara Gopinath wrote: > Sysfs interface to update cooling device cur_state does not > currently holding cooling device lock sometimes leading to > stale values in cur_state if getting updated simultanelously > from user space and thermal framework. Adding the proper locking > code fixes this issue. > > Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org> > --- > > V1->V2: Rearranged the code as per Daniel's review comment Hi Eduardo, Daniel Any comments on this ? Regards Thara > > drivers/thermal/thermal_sysfs.c | 11 +++++++---- > 1 file changed, 7 insertions(+), 4 deletions(-) > > diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c > index 2241cea..aa99edb 100644 > --- a/drivers/thermal/thermal_sysfs.c > +++ b/drivers/thermal/thermal_sysfs.c > @@ -712,11 +712,14 @@ cur_state_store(struct device *dev, struct device_attribute *attr, > if ((long)state < 0) > return -EINVAL; > > + mutex_lock(&cdev->lock); > + > result = cdev->ops->set_cur_state(cdev, state); > - if (result) > - return result; > - thermal_cooling_device_stats_update(cdev, state); > - return count; > + if (!result) > + thermal_cooling_device_stats_update(cdev, state); > + > + mutex_unlock(&cdev->lock); > + return result ? result : count; > } > > static struct device_attribute >
On 三, 2019-01-02 at 21:29 -0500, Thara Gopinath wrote: > On 11/27/2018 05:43 PM, Thara Gopinath wrote: > > > > Sysfs interface to update cooling device cur_state does not > > currently holding cooling device lock sometimes leading to > > stale values in cur_state if getting updated simultanelously > > from user space and thermal framework. Adding the proper locking > > code fixes this issue. > > > > Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org> > > --- > > > > V1->V2: Rearranged the code as per Daniel's review comment > Hi Eduardo, Daniel > > Any comments on this ? > it's already in my tree, and will be included in my pull request which will be sent out soon. thanks, rui > Regards > Thara > > > > > > > drivers/thermal/thermal_sysfs.c | 11 +++++++---- > > 1 file changed, 7 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/thermal/thermal_sysfs.c > > b/drivers/thermal/thermal_sysfs.c > > index 2241cea..aa99edb 100644 > > --- a/drivers/thermal/thermal_sysfs.c > > +++ b/drivers/thermal/thermal_sysfs.c > > @@ -712,11 +712,14 @@ cur_state_store(struct device *dev, struct > > device_attribute *attr, > > if ((long)state < 0) > > return -EINVAL; > > > > + mutex_lock(&cdev->lock); > > + > > result = cdev->ops->set_cur_state(cdev, state); > > - if (result) > > - return result; > > - thermal_cooling_device_stats_update(cdev, state); > > - return count; > > + if (!result) > > + thermal_cooling_device_stats_update(cdev, state); > > + > > + mutex_unlock(&cdev->lock); > > + return result ? result : count; > > } > > > > static struct device_attribute > > > >
diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c index 2241cea..aa99edb 100644 --- a/drivers/thermal/thermal_sysfs.c +++ b/drivers/thermal/thermal_sysfs.c @@ -712,11 +712,14 @@ cur_state_store(struct device *dev, struct device_attribute *attr, if ((long)state < 0) return -EINVAL; + mutex_lock(&cdev->lock); + result = cdev->ops->set_cur_state(cdev, state); - if (result) - return result; - thermal_cooling_device_stats_update(cdev, state); - return count; + if (!result) + thermal_cooling_device_stats_update(cdev, state); + + mutex_unlock(&cdev->lock); + return result ? result : count; } static struct device_attribute
Sysfs interface to update cooling device cur_state does not currently holding cooling device lock sometimes leading to stale values in cur_state if getting updated simultanelously from user space and thermal framework. Adding the proper locking code fixes this issue. Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org> --- V1->V2: Rearranged the code as per Daniel's review comment drivers/thermal/thermal_sysfs.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) -- 2.1.4