On 8/23/23 02:29, peter.wang@xxxxxxxxxxxx wrote:
From: Peter Wang <peter.wang@xxxxxxxxxxxx>
When ufshcd_clk_scaling_suspend_work(Thread A) running and new command
coming, ufshcd_clk_scaling_start_busy(Thread B) may get host_lock
after Thread A first time release host_lock. Then Thread A second time
get host_lock will set clk_scaling.window_start_t = 0 which scale up
clock abnormal next polling_ms time.
Below is racing step:
1 hba->clk_scaling.suspend_work (Thread A)
ufshcd_clk_scaling_suspend_work
2 spin_lock_irqsave(hba->host->host_lock, irq_flags);
3 hba->clk_scaling.is_suspended = true;
4 spin_unlock_irqrestore(hba->host->host_lock, irq_flags);
__ufshcd_suspend_clkscaling
7 spin_lock_irqsave(hba->host->host_lock, flags);
8 hba->clk_scaling.window_start_t = 0;
9 spin_unlock_irqrestore(hba->host->host_lock, flags);
ufshcd_send_command (Thread B)
ufshcd_clk_scaling_start_busy
5 spin_lock_irqsave(hba->host->host_lock, flags);
....
6 spin_unlock_irqrestore(hba->host->host_lock, flags);
Signed-off-by: Peter Wang <peter.wang@xxxxxxxxxxxx>
---
drivers/ufs/core/ufshcd.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index e3672e55efae..017f32b3a789 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -1385,9 +1385,10 @@ static void ufshcd_clk_scaling_suspend_work(struct work_struct *work)
return;
}
hba->clk_scaling.is_suspended = true;
+ hba->clk_scaling.window_start_t = 0;
spin_unlock_irqrestore(hba->host->host_lock, irq_flags);
- __ufshcd_suspend_clkscaling(hba);
+ devfreq_suspend_device(hba->devfreq);
}
static void ufshcd_clk_scaling_resume_work(struct work_struct *work)
There is a second __ufshcd_suspend_clkscaling() call in the same source
file. Please fix that call too.
Thanks,
Bart.
