On Mon, May 11, 2020 at 07:03:05PM -0700, Hemant Kumar wrote:
> Remove the system error worker thread and instead have the
> execution environment worker handle that transition to serialize
> processing and avoid any possible race conditions during
> shutdown.
>
> Signed-off-by: Hemant Kumar <hemantk@xxxxxxxxxxxxxx>
> Reviewed-by: Jeffrey Hugo <jhugo@xxxxxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Thanks,
Mani
> ---
> drivers/bus/mhi/core/init.c | 2 +-
> drivers/bus/mhi/core/internal.h | 3 ++-
> drivers/bus/mhi/core/main.c | 6 +++---
> drivers/bus/mhi/core/pm.c | 32 ++++++++++++++------------------
> include/linux/mhi.h | 2 --
> 5 files changed, 20 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
> index 6882206..3a853c5 100644
> --- a/drivers/bus/mhi/core/init.c
> +++ b/drivers/bus/mhi/core/init.c
> @@ -34,6 +34,7 @@
> [DEV_ST_TRANSITION_READY] = "READY",
> [DEV_ST_TRANSITION_SBL] = "SBL",
> [DEV_ST_TRANSITION_MISSION_MODE] = "MISSION_MODE",
> + [DEV_ST_TRANSITION_SYS_ERR] = "SYS_ERR",
> };
>
> const char * const mhi_state_str[MHI_STATE_MAX] = {
> @@ -834,7 +835,6 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl,
> spin_lock_init(&mhi_cntrl->transition_lock);
> spin_lock_init(&mhi_cntrl->wlock);
> INIT_WORK(&mhi_cntrl->st_worker, mhi_pm_st_worker);
> - INIT_WORK(&mhi_cntrl->syserr_worker, mhi_pm_sys_err_worker);
> init_waitqueue_head(&mhi_cntrl->state_event);
>
> mhi_cmd = mhi_cntrl->mhi_cmd;
> diff --git a/drivers/bus/mhi/core/internal.h b/drivers/bus/mhi/core/internal.h
> index 80b32c2..f01283b 100644
> --- a/drivers/bus/mhi/core/internal.h
> +++ b/drivers/bus/mhi/core/internal.h
> @@ -386,6 +386,7 @@ enum dev_st_transition {
> DEV_ST_TRANSITION_READY,
> DEV_ST_TRANSITION_SBL,
> DEV_ST_TRANSITION_MISSION_MODE,
> + DEV_ST_TRANSITION_SYS_ERR,
> DEV_ST_TRANSITION_MAX,
> };
>
> @@ -587,7 +588,7 @@ enum mhi_pm_state __must_check mhi_tryset_pm_state(
> int mhi_queue_state_transition(struct mhi_controller *mhi_cntrl,
> enum dev_st_transition state);
> void mhi_pm_st_worker(struct work_struct *work);
> -void mhi_pm_sys_err_worker(struct work_struct *work);
> +void mhi_pm_sys_err_handler(struct mhi_controller *mhi_cntrl);
> void mhi_fw_load_worker(struct work_struct *work);
> int mhi_ready_state_transition(struct mhi_controller *mhi_cntrl);
> void mhi_ctrl_ev_task(unsigned long data);
> diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c
> index 6a80666..9ec9b36 100644
> --- a/drivers/bus/mhi/core/main.c
> +++ b/drivers/bus/mhi/core/main.c
> @@ -406,7 +406,7 @@ irqreturn_t mhi_intvec_threaded_handler(int irq_number, void *dev)
> if (MHI_IN_PBL(ee))
> mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_FATAL_ERROR);
> else
> - schedule_work(&mhi_cntrl->syserr_worker);
> + mhi_pm_sys_err_handler(mhi_cntrl);
> }
>
> exit_intvec:
> @@ -734,7 +734,7 @@ int mhi_process_ctrl_ev_ring(struct mhi_controller *mhi_cntrl,
> MHI_PM_SYS_ERR_DETECT);
> write_unlock_irq(&mhi_cntrl->pm_lock);
> if (new_state == MHI_PM_SYS_ERR_DETECT)
> - schedule_work(&mhi_cntrl->syserr_worker);
> + mhi_pm_sys_err_handler(mhi_cntrl);
> break;
> }
> default:
> @@ -920,7 +920,7 @@ void mhi_ctrl_ev_task(unsigned long data)
> }
> write_unlock_irq(&mhi_cntrl->pm_lock);
> if (pm_state == MHI_PM_SYS_ERR_DETECT)
> - schedule_work(&mhi_cntrl->syserr_worker);
> + mhi_pm_sys_err_handler(mhi_cntrl);
> }
> }
>
> diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
> index 3cc238a..d9964d4 100644
> --- a/drivers/bus/mhi/core/pm.c
> +++ b/drivers/bus/mhi/core/pm.c
> @@ -449,19 +449,8 @@ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl,
> to_mhi_pm_state_str(transition_state));
>
> /* We must notify MHI control driver so it can clean up first */
> - if (transition_state == MHI_PM_SYS_ERR_PROCESS) {
> - /*
> - * If controller supports RDDM, we do not process
> - * SYS error state, instead we will jump directly
> - * to RDDM state
> - */
> - if (mhi_cntrl->rddm_image) {
> - dev_dbg(dev,
> - "Controller supports RDDM, so skip SYS_ERR\n");
> - return;
> - }
> + if (transition_state == MHI_PM_SYS_ERR_PROCESS)
> mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_SYS_ERROR);
> - }
>
> mutex_lock(&mhi_cntrl->pm_mutex);
> write_lock_irq(&mhi_cntrl->pm_lock);
> @@ -527,7 +516,6 @@ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl,
> mutex_unlock(&mhi_cntrl->pm_mutex);
> dev_dbg(dev, "Waiting for all pending threads to complete\n");
> wake_up_all(&mhi_cntrl->state_event);
> - flush_work(&mhi_cntrl->st_worker);
>
> dev_dbg(dev, "Reset all active channels and remove MHI devices\n");
> device_for_each_child(mhi_cntrl->cntrl_dev, NULL, mhi_destroy_device);
> @@ -607,13 +595,17 @@ int mhi_queue_state_transition(struct mhi_controller *mhi_cntrl,
> }
>
> /* SYS_ERR worker */
> -void mhi_pm_sys_err_worker(struct work_struct *work)
> +void mhi_pm_sys_err_handler(struct mhi_controller *mhi_cntrl)
> {
> - struct mhi_controller *mhi_cntrl = container_of(work,
> - struct mhi_controller,
> - syserr_worker);
> + struct device *dev = &mhi_cntrl->mhi_dev->dev;
> +
> + /* skip if controller supports RDDM */
> + if (mhi_cntrl->rddm_image) {
> + dev_dbg(dev, "Controller supports RDDM, skip SYS_ERROR\n");
> + return;
> + }
>
> - mhi_pm_disable_transition(mhi_cntrl, MHI_PM_SYS_ERR_PROCESS);
> + mhi_queue_state_transition(mhi_cntrl, DEV_ST_TRANSITION_SYS_ERR);
> }
>
> /* Device State Transition worker */
> @@ -661,6 +653,10 @@ void mhi_pm_st_worker(struct work_struct *work)
> case DEV_ST_TRANSITION_READY:
> mhi_ready_state_transition(mhi_cntrl);
> break;
> + case DEV_ST_TRANSITION_SYS_ERR:
> + mhi_pm_disable_transition
> + (mhi_cntrl, MHI_PM_SYS_ERR_PROCESS);
> + break;
> default:
> break;
> }
> diff --git a/include/linux/mhi.h b/include/linux/mhi.h
> index 2b20b9c..b008914 100644
> --- a/include/linux/mhi.h
> +++ b/include/linux/mhi.h
> @@ -331,7 +331,6 @@ struct mhi_controller_config {
> * @wlock: Lock for protecting device wakeup
> * @mhi_link_info: Device bandwidth info
> * @st_worker: State transition worker
> - * @syserr_worker: System error worker
> * @state_event: State change event
> * @status_cb: CB function to notify power states of the device (required)
> * @wake_get: CB function to assert device wake (optional)
> @@ -411,7 +410,6 @@ struct mhi_controller {
> spinlock_t wlock;
> struct mhi_link_info mhi_link_info;
> struct work_struct st_worker;
> - struct work_struct syserr_worker;
> wait_queue_head_t state_event;
>
> void (*status_cb)(struct mhi_controller *mhi_cntrl,
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
