Messages in this thread | | | Date | Mon, 10 Feb 2020 09:28:38 +0800 | From | Can Guo <> | Subject | Re: [PATCH v7 5/8] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic |
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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@codeaurora.org> >> Reviewed-by: Hongwu Su <hongwus@codeaurora.org> >> Reviewed-by: Asutosh Das <asutoshd@codeaurora.org> >> Reviewed-by: Bean Huo <beanhuo@micron.com> >> Reviewed-by: Stanley Chu <stanley.chu@mediatek.com> >> --- >> 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?
Regards, Can Guo.
>> -- >> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora >> Forum, >> a Linux Foundation Collaborative Project
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