Netdev List
 help / color / mirror / Atom feed
From: Justin Lai <justinlai0215@realtek.com>
To: Alexander Lobakin <aleksander.lobakin@intel.com>
Cc: "kuba@kernel.org" <kuba@kernel.org>,
	"davem@davemloft.net" <davem@davemloft.net>,
	"edumazet@google.com" <edumazet@google.com>,
	"pabeni@redhat.com" <pabeni@redhat.com>,
	"andrew+netdev@lunn.ch" <andrew+netdev@lunn.ch>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"horms@kernel.org" <horms@kernel.org>,
	Ping-Ke Shih <pkshih@realtek.com>,
	Larry Chiu <larry.chiu@realtek.com>
Subject: RE: [PATCH] rtase: Avoid sleeping in get_stats64()
Date: Tue, 2 Jun 2026 10:50:13 +0000	[thread overview]
Message-ID: <c3ca6a679d694890828ac9e7cc2d6305@realtek.com> (raw)
In-Reply-To: <f4b96c08-c6f7-422f-aceb-aa48fa2bfef6@intel.com>

> From: Justin Lai <justinlai0215@realtek.com>
> Date: Mon, 1 Jun 2026 14:24:47 +0800
> 
> > The .ndo_get_stats64 callback must not sleep because it can be called
> > when reading /proc/net/dev.
> >
> > rtase_get_stats64() calls rtase_dump_tally_counter(), which polls the
> > tally counter dump bit with read_poll_timeout(). This may sleep while
> > waiting for the hardware counter dump to complete.
> >
> > Use read_poll_timeout_atomic() instead to avoid sleeping in the
> > get_stats64() path.
> >
> > Signed-off-by: Justin Lai <justinlai0215@realtek.com>
> 
> Looks legit.
> 
> One question: for how long can this poll for in real life scenarios? Up to ~1 ms
> is okay-ish for atomic, but if longer, then you'd better to split it into shorter
> polls and reschedule() time to time.
> 
> Thanks,
> Olek

Hi Olek,
 
Thanks for the review.
 
On our test platform, the tally dump operation typically
completes in about 25 us. The 250 us timeout is a
conservative value.
 
I'll add the Fixes tag and resend this patch targeting
the net tree.
 
Thanks,
Justin

  parent reply	other threads:[~2026-06-02 11:00 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-06-01  6:24 [PATCH] rtase: Avoid sleeping in get_stats64() Justin Lai
2026-06-01 13:14 ` Alexander Lobakin
2026-06-01 21:42   ` David Laight
2026-06-02 13:43     ` Alexander Lobakin
2026-06-02 10:50   ` Justin Lai [this message]
2026-06-02 18:09     ` Jakub Kicinski

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=c3ca6a679d694890828ac9e7cc2d6305@realtek.com \
    --to=justinlai0215@realtek.com \
    --cc=aleksander.lobakin@intel.com \
    --cc=andrew+netdev@lunn.ch \
    --cc=davem@davemloft.net \
    --cc=edumazet@google.com \
    --cc=horms@kernel.org \
    --cc=kuba@kernel.org \
    --cc=larry.chiu@realtek.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=pabeni@redhat.com \
    --cc=pkshih@realtek.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox