From: Stanley Chu <stanley.chu@mediatek.com>
To: Can Guo <cang@codeaurora.org>
Cc: <asutoshd@codeaurora.org>, <nguyenb@codeaurora.org>,
<hongwus@codeaurora.org>, <linux-scsi@vger.kernel.org>,
<kernel-team@android.com>, Alim Akhtar <alim.akhtar@samsung.com>,
Avri Altman <avri.altman@wdc.com>,
"James E.J. Bottomley" <jejb@linux.ibm.com>,
"Martin K. Petersen" <martin.petersen@oracle.com>,
Bean Huo <beanhuo@micron.com>,
"Satya Tangirala" <satyat@google.com>,
Adrian Hunter <adrian.hunter@intel.com>,
open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v11 1/3] scsi: ufs: Protect some contexts from unexpected clock scaling
Date: Wed, 20 Jan 2021 21:14:32 +0800 [thread overview]
Message-ID: <1611148472.1261.6.camel@mtkswgap22> (raw)
In-Reply-To: <1611137065-14266-2-git-send-email-cang@codeaurora.org>
On Wed, 2021-01-20 at 02:04 -0800, Can Guo wrote:
> In contexts like suspend, shutdown and error handling, we need to suspend
> devfreq to make sure these contexts won't be disturbed by clock scaling.
> However, suspending devfreq is not enough since users can still trigger a
> clock scaling by manipulating the devfreq sysfs nodes like min/max_freq and
> governor even after devfreq is suspended. Moreover, mere suspending devfreq
> cannot synchroinze a clock scaling which has already been invoked through
> these sysfs nodes. Add one more flag in struct clk_scaling and wrap the
> entire func ufshcd_devfreq_scale() with the clk_scaling_lock, so that we
> can use this flag and clk_scaling_lock to control and synchronize clock
> scaling invoked through devfreq sysfs nodes.
>
> Signed-off-by: Can Guo <cang@codeaurora.org>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
next prev parent reply other threads:[~2021-01-20 13:19 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-20 10:04 [PATCH v11 0/3] Three changes related with UFS clock scaling Can Guo
2021-01-20 10:04 ` [PATCH v11 1/3] scsi: ufs: Protect some contexts from unexpected " Can Guo
2021-01-20 13:14 ` Stanley Chu [this message]
2021-01-20 10:04 ` [PATCH v11 2/3] scsi: ufs: Refactor ufshcd_init/exit_clk_scaling/gating() Can Guo
2021-01-20 10:04 ` Can Guo
2021-01-20 10:04 ` Can Guo
2021-01-20 10:04 ` [PATCH v11 3/3] scsi: ufs: Revert "Make sure clk scaling happens only when HBA is runtime ACTIVE" Can Guo
2021-01-20 10:04 ` Can Guo
2021-01-20 10:04 ` Can Guo
2021-01-21 3:28 ` [PATCH v11 0/3] Three changes related with UFS clock scaling Martin K. Petersen
2021-01-23 4:22 ` Martin K. Petersen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1611148472.1261.6.camel@mtkswgap22 \
--to=stanley.chu@mediatek.com \
--cc=adrian.hunter@intel.com \
--cc=alim.akhtar@samsung.com \
--cc=asutoshd@codeaurora.org \
--cc=avri.altman@wdc.com \
--cc=beanhuo@micron.com \
--cc=cang@codeaurora.org \
--cc=hongwus@codeaurora.org \
--cc=jejb@linux.ibm.com \
--cc=kernel-team@android.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
--cc=martin.petersen@oracle.com \
--cc=nguyenb@codeaurora.org \
--cc=satyat@google.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.