[PATCH 09/14] bus: mhi: core: Remove the system error worker thread

mani
2020-05-21T15:26:37Z

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@codeaurora.org>
Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
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 6882206ad80e..3a853c5d2103 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -34,6 +34,7 @@ const char * const dev_state_tran_str[DEV_ST_TRANSITION_MAX] = {
[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 80b32c20149c..f01283b8a451 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_ee_type mhi_get_exec_env(struct mhi_controller *mhi_cntrl);
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 a394691d9383..e5f6500e89fd 100644
--- a/drivers/bus/mhi/core/main.c
+++ b/drivers/bus/mhi/core/main.c
@@ -405,7 +405,7 @@ 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:
@@ -733,7 +733,7 @@ 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:
@@ -919,7 +919,7 @@ 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 6d56441013af..743b3207c390 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 a60312927b4d..642ef1f40a2b 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,
--
2.26.GIT