Hi > > > > There is no mutex protecting of these state checking, which can't > > garantee there is no another instance is trying to do same operation. > > > > The reference counter rproc->power is used to manage state changing > > and there is mutex protection in each operation function for multi > > instance case. > > > > So remove this state checking in rproc_cdev_write() and state_store(), > > just let reference counter rproc->power to manage the behaviors. > > > > Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx> > > --- > > drivers/remoteproc/remoteproc_cdev.c | 11 ----------- > > drivers/remoteproc/remoteproc_sysfs.c | 11 ----------- > > 2 files changed, 22 deletions(-) > > > > diff --git a/drivers/remoteproc/remoteproc_cdev.c > > b/drivers/remoteproc/remoteproc_cdev.c > > index 906ff3c4dfdd..687f205fd70a 100644 > > --- a/drivers/remoteproc/remoteproc_cdev.c > > +++ b/drivers/remoteproc/remoteproc_cdev.c > > @@ -32,21 +32,10 @@ static ssize_t rproc_cdev_write(struct file *filp, > const char __user *buf, size_ > > return -EFAULT; > > > > if (!strncmp(cmd, "start", len)) { > > - if (rproc->state == RPROC_RUNNING || > > - rproc->state == RPROC_ATTACHED) > > - return -EBUSY; > > - > > ret = rproc_boot(rproc); > > } else if (!strncmp(cmd, "stop", len)) { > > - if (rproc->state != RPROC_RUNNING && > > - rproc->state != RPROC_ATTACHED) > > - return -EINVAL; > > - > > ret = rproc_shutdown(rproc); > > } else if (!strncmp(cmd, "detach", len)) { > > - if (rproc->state != RPROC_ATTACHED) > > - return -EINVAL; > > - > > ret = rproc_detach(rproc); > > } else { > > dev_err(&rproc->dev, "Unrecognized option\n"); diff > > --git a/drivers/remoteproc/remoteproc_sysfs.c > > b/drivers/remoteproc/remoteproc_sysfs.c > > index 51a04bc6ba7a..8c7ea8922638 100644 > > --- a/drivers/remoteproc/remoteproc_sysfs.c > > +++ b/drivers/remoteproc/remoteproc_sysfs.c > > @@ -194,23 +194,12 @@ static ssize_t state_store(struct device *dev, > > int ret = 0; > > > > if (sysfs_streq(buf, "start")) { > > - if (rproc->state == RPROC_RUNNING || > > - rproc->state == RPROC_ATTACHED) > > - return -EBUSY; > > - > > As per my previous comment the above conditions need to be moved into > rproc_boot(). > > > ret = rproc_boot(rproc); > > if (ret) > > dev_err(&rproc->dev, "Boot failed: %d\n", ret); > > } else if (sysfs_streq(buf, "stop")) { > > - if (rproc->state != RPROC_RUNNING && > > - rproc->state != RPROC_ATTACHED) > > - return -EINVAL; > > - > > ret = rproc_shutdown(rproc); > > } else if (sysfs_streq(buf, "detach")) { > > - if (rproc->state != RPROC_ATTACHED) > > - return -EINVAL; > > - > > This patch should have been part of a patch series with your other work sent > on March 18th[1]. > > Thanks, > Mathieu > > [1]. [PATCH] remoteproc: core: check rproc->power value before decreasing > it > Thanks for the comments. I still have one question, if there are two instances independently to 'start' 'stop' remoteproc, for example: Instance1: echo start > /sys/class/remoteproc/remoteproc0/state Instance2: echo start > /sys/class/remoteproc/remoteproc0/state ... Instance2: echo stop > /sys/class/remoteproc/remoteproc0/state ... Instance1: echo stop > /sys/class/remoteproc/remoteproc0/state When instance2 'stop' the remoteproc, then instance1 will be impacted for It still needs the service from remoteproc. That's why I just removed of the checking state, didn't move them to rproc_boot()/rproc_shutdown()/rproc_detach(). And in order to utilize the reference counter (rproc->power) to handle the multi-instance case. Best regards Wang Shengjiu