From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Emil Tantilov <emil.s.tantilov@intel.com>
Cc: intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org,
anthony.l.nguyen@intel.com, aleksandr.loktionov@intel.com,
przemyslaw.kitszel@intel.com, andrew+netdev@lunn.ch,
davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
pabeni@redhat.com, clrkwllms@kernel.org, rostedt@goodmis.org,
linux-rt-devel@lists.linux.dev, sgzhang@google.com,
boolli@google.com, stable@vger.kernel.org
Subject: Re: [PATCH iwl-net v2 2/3] idpf: improve locking around idpf_vc_xn_push_free()
Date: Fri, 20 Mar 2026 08:42:45 +0100 [thread overview]
Message-ID: <20260320074245.f8dPuv4j@linutronix.de> (raw)
In-Reply-To: <20260319211335.23236-3-emil.s.tantilov@intel.com>
On 2026-03-19 14:13:34 [-0700], Emil Tantilov wrote:
> drivers/net/ethernet/intel/idpf/idpf_virtchnl.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c b/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
> index 582e0c8e9dc0..fbd5a15b015c 100644
> --- a/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
> +++ b/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
> @@ -402,7 +402,9 @@ static void idpf_vc_xn_push_free(struct idpf_vc_xn_manager *vcxn_mngr,
> struct idpf_vc_xn *xn)
> {
> idpf_vc_xn_release_bufs(xn);
> + spin_lock_bh(&vcxn_mngr->xn_bm_lock);
> set_bit(xn->idx, vcxn_mngr->free_xn_bm);
If all of your bit manipulations happen under the same lock you could
replace atomic set_bit()/ clear_bit() with their non-atomic counter
parts __set_bit()/ __clear_bit().
The lockless alternative would be find_first_bit() +
test_and_set_bit() loop. Probably another atomic op for salt. Using the
__ is free with this change.
> + spin_unlock_bh(&vcxn_mngr->xn_bm_lock);
> }
Sebastian
next prev parent reply other threads:[~2026-03-20 7:42 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-19 21:13 [PATCH iwl-net v2 0/3] idpf: virtchnl locking and async fixes Emil Tantilov
2026-03-19 21:13 ` [PATCH iwl-net v2 1/3] idpf: fix PREEMPT_RT raw/bh spinlock nesting for async VC handling Emil Tantilov
2026-03-20 7:23 ` Loktionov, Aleksandr
2026-03-19 21:13 ` [PATCH iwl-net v2 2/3] idpf: improve locking around idpf_vc_xn_push_free() Emil Tantilov
2026-03-20 7:23 ` Loktionov, Aleksandr
2026-03-20 7:42 ` Sebastian Andrzej Siewior [this message]
2026-03-23 16:20 ` Tantilov, Emil S
2026-03-19 21:13 ` [PATCH iwl-net v2 3/3] idpf: set the payload size before calling the async handler Emil Tantilov
2026-03-20 7:35 ` [PATCH iwl-net v2 0/3] idpf: virtchnl locking and async fixes Sebastian Andrzej Siewior
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=20260320074245.f8dPuv4j@linutronix.de \
--to=bigeasy@linutronix.de \
--cc=aleksandr.loktionov@intel.com \
--cc=andrew+netdev@lunn.ch \
--cc=anthony.l.nguyen@intel.com \
--cc=boolli@google.com \
--cc=clrkwllms@kernel.org \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=emil.s.tantilov@intel.com \
--cc=intel-wired-lan@lists.osuosl.org \
--cc=kuba@kernel.org \
--cc=linux-rt-devel@lists.linux.dev \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=przemyslaw.kitszel@intel.com \
--cc=rostedt@goodmis.org \
--cc=sgzhang@google.com \
--cc=stable@vger.kernel.org \
/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