From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 7374414F136; Fri, 28 Jun 2024 16:39:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719592795; cv=none; b=ekSyjM0Va9WwTp3WCwIBxPHz5Bl278HdKQBxMIRPsARK/bm8eeBSBogGGbwVpAl12tF7Gxwu5UO/dynq33+EDFZiNmQQuMlEVZ4Yx5c41YFE7cwjvIqGeqgtnV3MrsloYiGtrKPGiaOW9I1uFvMwijvNhYnCScnT0OTIbIMg2yU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719592795; c=relaxed/simple; bh=fn+F6SB9Tmcyy/VXFEjpwkfaczJIJalSNRk3f6//HJ0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=gLkQaXQJpXhMYqJXISqJGCtfDrsq2KOlSqVi0Hzsx8wn6f9MeqeysDdz68z3bubzxoG1BsuypChyuV5T4ose/BDhh/PydXk8JGSYfh+x1emSIXhfg0Ji54ohhfnxhT9ydZEPHYiSDhj48DA7sglcNvV6MqOUUt+N9NsPBlCjH7A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tCogznlg; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tCogznlg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A1D29C116B1; Fri, 28 Jun 2024 16:39:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1719592794; bh=fn+F6SB9Tmcyy/VXFEjpwkfaczJIJalSNRk3f6//HJ0=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=tCogznlguilz2w8zBT7Jn9wl9oLOImWzxPVJdCpLfNQCpYWZckN3/jCvNdoWS3dlC /uMMzd4MrCrq75hEO4iXUg5/1ppaRa7OgIQ/TvKCD83XJZKc9wng/nlFzHyMOMoJmj p6GtGIg1+DnzbCe4K9T4Dj5uIajFVLfur5bzs8WgogZ3okn/QB5r1sIp94z1+fDoca 6NLwGKYmP+OR6wkqHdd0+6fteSk2znob2bFTikv19Yu8pnHNfqiLzSpdaACvhQ53Cj AHbth61dJzI1AZHi4GvMNpeA6WlOIt7Z6BXI7QtHeGjt05s3m9imqUyMiJ+ZBeV7TC 43Y+T/43MSTRA== Message-ID: Date: Fri, 28 Jun 2024 18:39:49 +0200 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next 3/3] net: Move flush list retrieval to where it is used. To: Sebastian Andrzej Siewior , netdev@vger.kernel.org, bpf@vger.kernel.org Cc: =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , "David S. Miller" , Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Eduard Zingerman , Eric Dumazet , Hao Luo , Jakub Kicinski , Jiri Olsa , John Fastabend , Jonathan Lemon , KP Singh , Maciej Fijalkowski , Magnus Karlsson , Martin KaFai Lau , Paolo Abeni , Song Liu , Stanislav Fomichev , Thomas Gleixner , Yonghong Song References: <20240628103020.1766241-1-bigeasy@linutronix.de> <20240628103020.1766241-4-bigeasy@linutronix.de> Content-Language: en-US From: Jesper Dangaard Brouer In-Reply-To: <20240628103020.1766241-4-bigeasy@linutronix.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 28/06/2024 12.18, Sebastian Andrzej Siewior wrote: > The bpf_net_ctx_get_.*_flush_list() are used at the top of the function. > This means the variable is always assigned even if unused. By moving the > function to where it is used, it is possible to delay the initialisation > until it is unavoidable. > Not sure how much this gains in reality but by looking at bq_enqueue() > (in devmap.c) gcc pushes one register less to the stack. \o/. > > Move flush list retrieval to where it is used. > > Signed-off-by: Sebastian Andrzej Siewior > --- > kernel/bpf/cpumap.c | 6 ++++-- > kernel/bpf/devmap.c | 3 ++- > net/xdp/xsk.c | 6 ++++-- > 3 files changed, 10 insertions(+), 5 deletions(-) Nice small optimization :-) Acked-by: Jesper Dangaard Brouer