From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.toke.dk (mail.toke.dk [45.145.95.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2108E32B9AE; Mon, 17 Nov 2025 11:47:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.145.95.4 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763380036; cv=none; b=rf5bzaKX71raR0x7fYUM64t9uaw3DKYKeN5+/NjDd6eAGhugBM/tc0L9gpgvt336FsBf3dNnbEf8dDqsNKsSApXexbyzIJPK3bWHmpSk9Znfgt36c0DHNTnkFRqfsHY8RJ6DtZ/sItN0o09Y/njoczSME3OIwlW1dy8ToTz9J94= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763380036; c=relaxed/simple; bh=18AThoJ1F5XQlVvAYjRYKKUnjnNDdRj8jhe5/a7p0Ss=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=fihHClnSu06lbwCCo62Xbt7+OoD3hFTTQQ4IH+bL2cCx4bpESFf/+pz7KtIOHyDNKGPnXwpXHHQM/+U2N9TvX+L8pi48mBLRnwGi+m/W0w3bR7AJnVZgOJ0CM9W/sKP5OfbZUONM9VCprJH3eJUuh1OarZKtHTcWBMG7XOcrWwk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=toke.dk; spf=pass smtp.mailfrom=toke.dk; dkim=pass (2048-bit key) header.d=toke.dk header.i=@toke.dk header.b=OER8VvtA; arc=none smtp.client-ip=45.145.95.4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=toke.dk Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=toke.dk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=toke.dk header.i=@toke.dk header.b="OER8VvtA" From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=toke.dk; s=20161023; t=1763380031; bh=18AThoJ1F5XQlVvAYjRYKKUnjnNDdRj8jhe5/a7p0Ss=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=OER8VvtAWTP0L0fklHIXgvMbFN6jQ42q7ikGcR7PT1lfcpE+sk1vaFPlgwmYfxh2u Pq0y/kJUlVETtENUzSDWBD29nZ2oAwTrefvL8GaBT/YWNG1U5Mjq4+u8N2zaMvWGEW D0+efZ3KilUrlzGa4RTfgyZqCWS8ZZBaKN5UMhTzrzKUnNddCaSBPAq9WMvcT+Ds69 3092p0XYV87EDLK8QwERXg2JcshEZMZcTB0vts1w1Xkp4t6mwezRfsELFuLCBJODqY ihba2OAwwWb9Fs/T1FQnHaijPFLuUVe/E+WYicL9bzWdCRfMuTnCXAFDCbIwAZWgF0 sOcUAGdTe3FmA== To: pengdonglin , tj@kernel.org, tony.luck@intel.com, jani.nikula@linux.intel.com, ap420073@gmail.com, jv@jvosburgh.net, freude@linux.ibm.com, bcrl@kvack.org, trondmy@kernel.org, longman@redhat.com, kees@kernel.org Cc: bigeasy@linutronix.de, hdanton@sina.com, paulmck@kernel.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, linux-nfs@vger.kernel.org, linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, netdev@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-wireless@vger.kernel.org, linux-acpi@vger.kernel.org, linux-s390@vger.kernel.org, cgroups@vger.kernel.org, pengdonglin , Jakub Kicinski , pengdonglin Subject: Re: [PATCH v3 14/14] wifi: ath9k: Remove redundant rcu_read_lock/unlock() in spin_lock In-Reply-To: <20250916044735.2316171-15-dolinux.peng@gmail.com> References: <20250916044735.2316171-1-dolinux.peng@gmail.com> <20250916044735.2316171-15-dolinux.peng@gmail.com> Date: Mon, 17 Nov 2025 12:47:07 +0100 X-Clacks-Overhead: GNU Terry Pratchett Message-ID: <87fracop8k.fsf@toke.dk> Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable pengdonglin writes: > From: pengdonglin > > Since commit a8bb74acd8efe ("rcu: Consolidate RCU-sched update-side funct= ion definitions") > there is no difference between rcu_read_lock(), rcu_read_lock_bh() and > rcu_read_lock_sched() in terms of RCU read section and the relevant grace > period. That means that spin_lock(), which implies rcu_read_lock_sched(), > also implies rcu_read_lock(). > > There is no need no explicitly start a RCU read section if one has already > been started implicitly by spin_lock(). > > Simplify the code and remove the inner rcu_read_lock() invocation. > > Cc: "Toke" > Cc: Jakub Kicinski > Signed-off-by: pengdonglin > Signed-off-by: pengdonglin Acked-by: Toke H=C3=B8iland-J=C3=B8rgensen