From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.9 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8DF29C4708F for ; Tue, 1 Jun 2021 17:20:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 72EA6613AE for ; Tue, 1 Jun 2021 17:20:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234562AbhFARV5 (ORCPT ); Tue, 1 Jun 2021 13:21:57 -0400 Received: from www62.your-server.de ([213.133.104.62]:40888 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231918AbhFARVy (ORCPT ); Tue, 1 Jun 2021 13:21:54 -0400 Received: from sslproxy02.your-server.de ([78.47.166.47]) by www62.your-server.de with esmtpsa (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92.3) (envelope-from ) id 1lo83g-000GKb-Tq; Tue, 01 Jun 2021 19:20:04 +0200 Received: from [85.7.101.30] (helo=linux.home) by sslproxy02.your-server.de with esmtpsa (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lo83g-000LRJ-Ku; Tue, 01 Jun 2021 19:20:04 +0200 Subject: Re: [PATCH 1/1] bpf: avoid unnecessary IPI in bpf_flush_icache To: Yanfei Xu , ast@kernel.org, zlim.lnx@gmail.com, catalin.marinas@arm.com, will@kernel.org, andrii@kernel.org, kafai@fb.com, songliubraving@fb.com, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20210601150625.37419-1-yanfei.xu@windriver.com> <20210601150625.37419-2-yanfei.xu@windriver.com> From: Daniel Borkmann Message-ID: <56cc1e25-25c3-a3da-64e3-8a1c539d685b@iogearbox.net> Date: Tue, 1 Jun 2021 19:20:04 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20210601150625.37419-2-yanfei.xu@windriver.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Authenticated-Sender: daniel@iogearbox.net X-Virus-Scanned: Clear (ClamAV 0.103.2/26188/Tue Jun 1 13:07:16 2021) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/1/21 5:06 PM, Yanfei Xu wrote: > It's no need to trigger IPI for keeping pipeline fresh in bpf case. This needs a more concrete explanation/analysis on "why it is safe" to do so rather than just saying that it is not needed. > Signed-off-by: Yanfei Xu > --- > arch/arm64/net/bpf_jit_comp.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c > index f7b194878a99..5311f8be4ba4 100644 > --- a/arch/arm64/net/bpf_jit_comp.c > +++ b/arch/arm64/net/bpf_jit_comp.c > @@ -974,7 +974,7 @@ static int validate_code(struct jit_ctx *ctx) > > static inline void bpf_flush_icache(void *start, void *end) > { > - flush_icache_range((unsigned long)start, (unsigned long)end); > + __flush_icache_range((unsigned long)start, (unsigned long)end); > } > > struct arm64_jit_data { >