On 2020-02-10 09:28, Can Guo wrote:
On 2020-02-06 18:28, Avri Altman wrote:
Hi,
The async version of ufshcd_hold(async == true), which is only called
in queuecommand path as for now, is expected to work in atomic
context,
thus it should not sleep or schedule out. When it runs into the
condition
that clocks are ON but link is still in hibern8 state, it should bail
out
without flushing the clock ungate work.
Fixes: f2a785ac2312 (scsi: ufshcd: Fix race between clk scaling and
ungate work)
Sorry, missed this one, if another version is needed, I will add this
line.
Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
Reviewed-by: Hongwu Su <hongwus@xxxxxxxxxxxxxx>
Reviewed-by: Asutosh Das <asutoshd@xxxxxxxxxxxxxx>
Reviewed-by: Bean Huo <beanhuo@xxxxxxxxxx>
Reviewed-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
---
drivers/scsi/ufs/ufshcd.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index bbc2607..e8f7f9d 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -1518,6 +1518,11 @@ int ufshcd_hold(struct ufs_hba *hba, bool
async)
*/
if (ufshcd_can_hibern8_during_gating(hba) &&
ufshcd_is_link_hibern8(hba)) {
+ if (async) {
+ rc = -EAGAIN;
+ hba->clk_gating.active_reqs--;
+ break;
+ }
spin_unlock_irqrestore(hba->host->host_lock,
flags);
flush_work(&hba->clk_gating.ungate_work);
spin_lock_irqsave(hba->host->host_lock,
flags);
Since now the above code is shared in all cases,
Maybe find a more economical way to pack it?
Thanks,
Avri
There are only 2 of this same code pieces in ufshcd_hold() and located
in different cases, meanwhile there can be fall through, I don't see
a good way to pack it, can you suggest if you have any ideas?
Now, with this patch, there are 2 same code snippets located in CLKS_ON
and REQ_CLKS_ON. If we somehow pack them, say bring in a inline func to
pack them, we would have to tear it down later if we have to fix
something for only one specific case by adding lines into the snippet.
And actually this is the truth, we do have some fixes for CLKS_ON's case
but not yet uploaded, so let's leave it as it is for now.
Regards,
Can Guo.
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
Forum,
a Linux Foundation Collaborative Project
