Received: by 2002:a25:ab43:0:0:0:0:0 with SMTP id u61csp1599757ybi; Sat, 8 Jun 2019 13:41:53 -0700 (PDT) X-Google-Smtp-Source: APXvYqwgx4DIwU7Ek2phX2jCa0zH2zxbK4pIqJXfmy424U04xb0VnNunel3HR/QBiYD2l9OGe7cT X-Received: by 2002:a17:90a:f498:: with SMTP id bx24mr13046953pjb.91.1560026513270; Sat, 08 Jun 2019 13:41:53 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1560026513; cv=none; d=google.com; s=arc-20160816; b=rvf3HRzoY1v0ut/93I23uEWhXhZ0IK92uHrVBQAgE1szJnMa1tYo4Ygr5xZhSPNC1U qUjixbgr3MZ4ieC4d7IYcuIDqrmG3+952J3gc9Wg1ujnFq1yKcc7utvV+zcqvHwPvURb CUh+oDh8k+6Mqfii/N7pRPUBNpEZEXFfPJN4PIWQiWg7sHaYp6JXhv5CZZRzWeq3pR+r 8Ku0YwsKy9M6hMcOkBKhPdTX/3imWZCKmYgFwDvZ6MOSHoxlAtk0kiYAAYezdgRT88hS KVtkHJKWevm+pbz7eVOSJTwv0sgoFCv9AfzsDaXIXMH588Sewarxwe2zki0ZQiWzgucX 3zfA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :references:in-reply-to:message-id:subject:cc:to:from:date; bh=QAnI1RGnCKz4SMmhpUnnuTeIsJ0jGJdPOY1geqN/oOA=; b=dKl5U7yZBZuodoqW/vSXFBhwpXyD5EfJPFZ/HAIU2B1iV7GfrT1TWzekP4FhWIgoiZ kJlLI2V33/5C89F8hEOkWWEt59MTTY1IxHFhphVZJ44Jcyncx+ucfs5F8uyVlpVKt8il V5L2bsejQabxb45mnnvyYqp4jaP2In8QtWrysIPehBGoiUKOhpuzxT2CP6XDFePNVQqE 03cLesfcSsCzpIPNzylYbNPm8LzjKZJADmq7vRhgh3EnT+TZhkbCeKnMbH3Oj1bezilG gpcHb10FrQGgl0afREM9HK6zNAf3Tqn7CxCb0a+jJSjslxhRjtCWldFCi9aWETNj6Bw4 lfOw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id y34si5709918plb.186.2019.06.08.13.41.36; Sat, 08 Jun 2019 13:41:53 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727612AbfFHUjg (ORCPT + 99 others); Sat, 8 Jun 2019 16:39:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:33058 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727324AbfFHUjg (ORCPT ); Sat, 8 Jun 2019 16:39:36 -0400 Received: from oasis.local.home (unknown [12.156.218.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E2992208E3; Sat, 8 Jun 2019 20:39:34 +0000 (UTC) Date: Sat, 8 Jun 2019 16:39:33 -0400 From: Steven Rostedt To: Song Liu Cc: Matt Mullins , "linux-kernel@vger.kernel.org" , "daniel@iogearbox.net" , "bpf@vger.kernel.org" , "ast@kernel.org" , Andrew Hall , "mingo@redhat.com" , "netdev@vger.kernel.org" , Martin Lau , Yonghong Song Subject: Re: [PATCH bpf] bpf: preallocate a perf_sample_data per event fd Message-ID: <20190608163933.50033e9f@oasis.local.home> In-Reply-To: References: <20190530225549.23014-1-mmullins@fb.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 31 May 2019 05:26:30 +0000 Song Liu wrote: > We can also do something like > > ee = kzalloc(sizeof(struct bpf_event_entry) + sizeof(struct perf_sample_data)); > ee->sd = (void *)ee + sizeof(struct bpf_event_entry); Or perhaps: ee->sd = (struct perf_sample_data *)(ee + 1); -- Steve