From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) (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 099A136681D; Fri, 6 Feb 2026 14:52:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.17 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770389560; cv=none; b=UWldzVMOSt72tz9H5HeCXGO+J0ts9hD9CEygzh7v6lXzcqITCT/+goozDdnoRwUrGYDvwl2r09UNHmkGVtMtLkniTy94UMYHggoPBv74HiBzuM8qogj8/QrmCI+8hd6Y42OPrENJuREJDmsxXzUPI9uq3YM9kZAC4ETTMGh7y7g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770389560; c=relaxed/simple; bh=Imx+USg/DGgQS6B0wl/CEttehRxN6qu/JL/qMO3CiP0=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=RiA+y3+vDs8yH8HwhCGZ2C6uWdbjp63t8s9LDZcANnQhR5Asl9eJ2Gh7/X5ztXtir/kyP3Wmtxdwr4S27kqkAfw9gwP8x+dggOchuifDg/4JuXtndKij56206EqkDbC7Kd1XdMYiWLtpIYYaW1g4f/Lk+Q9Uj4zcLy2P1uA9mqw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id AE56C1A01CC; Fri, 6 Feb 2026 14:52:32 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf06.hostedemail.com (Postfix) with ESMTPA id 07EC22000F; Fri, 6 Feb 2026 14:52:30 +0000 (UTC) Date: Fri, 6 Feb 2026 09:53:09 -0500 From: Steven Rostedt To: "Colin Lord" Cc: , , "Masami Hiramatsu" , "Mathieu Desnoyers" Subject: Re: [PATCH v2] trace/hwlat: prevent false sharing in get_sample() Message-ID: <20260206095309.2fe4f4d3@gandalf.local.home> In-Reply-To: References: <20260202025838.32057-1-clord@mykolab.com> <20260205094722.6d21d8b0@gandalf.local.home> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 07EC22000F X-Stat-Signature: oy1ym6ndcjjh6inphmeeg64833uq87r8 X-Rspamd-Server: rspamout08 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1+AAK1AC7tDWiCTxOHd3LkOZmdyLtZzb9Y= X-HE-Tag: 1770389550-914339 X-HE-Meta: U2FsdGVkX19N0SX2ceA8vSzjICv8JbKXrxNUPdSrX5efV2ZLEdfiIs2HGEmaRtHV3LaMGAdNOFHmcOfidvY+dxQa787YPq1ESa/I/n0a+IXXci2J8sUnCEcmPg28DF37kJi2oKnTClN3ljA8s+g5ME6nHlM4xMw5y6APtUKB8ofeO+y5QkI2pgRIw4zgYBin3MtAAhy7zl+KDZED+cihIYpFx7XWtYSeRtBJB4u/wSr08Nd00GHz/UgfzYoeUPlNgFBOkZcWS0XYwsB9RPF5rEZEPiYoreXAWzYMRMliEvDk2xBjJHZQOgphVbqA22bYQvleh8c0B9ygT1dlF3N9L8vXznW+xb9HjyuOvuaLLj8kjWWOubvXopYYx99lY9NZ On Fri, 06 Feb 2026 00:09:49 -0800 "Colin Lord" wrote: > > tracing: Fix get_sample() in hwlat from ... > > Got it, I can make that adjustment and resend. Would you also like me to > modify the commit message with any of the above clarifications? Yes please. Mention the cache sharing issues and that you saw missed/duplicate seqnums too. Not everyone knows what "false sharing" is (I forgot what it was ;). You can use the term, but also explain it in terms of cache like you did in this email. Thanks, -- Steve