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 BE2A81AA1F4; Sat, 2 May 2026 19:23:15 +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=1777749797; cv=none; b=HXOmn2jxvkVPyK7fFwS1RVW5SMriT8/fNHe3wZdREbXn1Y3vQZWJz+4kUjyAsEvKe+saCiY0rqceDxstlAULl5wU+6ZFd1zyAdlLpxeN/t2jY+kO+EVi1ineg5/cDn8ZAu7kw28U5qM/QlgdKI00mIyjCY3jQoyGTz5HHc171jM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777749797; c=relaxed/simple; bh=vDi4xGv0q98PNW1jXr84JP3EVfHUo37AUzpjy5K55K4=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=b8uLtTxMEObEV3ROD6/ASXlabRRmx7l/zXmKzIn4Lb7efmdN08gen5ZBH/7iIu9V75SYSKpfjba9xZBDBtqgD6hRztIEsqEhZj9h2YkxG/8lHNbROA4pVSq3TNgW7TER+q4z3vt2k5X8jpW3UrH9awEjn9uSoItM4q+Sl60+8JE= 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 omf16.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 410F6160524; Sat, 2 May 2026 19:23:08 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf16.hostedemail.com (Postfix) with ESMTPA id 3A49C20018; Sat, 2 May 2026 19:23:06 +0000 (UTC) Date: Sat, 2 May 2026 15:23:04 -0400 From: Steven Rostedt To: "Masami Hiramatsu (Google)" Cc: Catalin Marinas , Will Deacon , Mathieu Desnoyers , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Ian Rogers , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v19 0/7] ring-buffer: Making persistent ring buffers robust Message-ID: <20260502152304.560a5954@robin> In-Reply-To: <177751968499.2136606.17388366710182662849.stgit@mhiramat.tok.corp.google.com> References: <177751968499.2136606.17388366710182662849.stgit@mhiramat.tok.corp.google.com> X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-redhat-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="MP_/bduRHcIgi7cE_At8/bu1uhd" X-Rspamd-Server: rspamout05 X-Rspamd-Queue-Id: 3A49C20018 X-Stat-Signature: 1p61ghnqdpke4wkizqjbgexfjuxxyhqw X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX19GhuIyQaIfEX0jv4huB7H5ggusR9h7p+8= X-HE-Tag: 1777749786-296731 X-HE-Meta: U2FsdGVkX19bUoGqhA2+ZC9WRj15X+DlVnMrZ9GL9LDsFXFqNWKrSedMwv9eDtwKQQY5jzSCeRN5ay+A/mpFH1V41iSgOsKuZmcRpJY7Q1nBf/36tTBCukt6pNL65VMzdFrjl5+rymlfb5aO289feVNy9DTZJ67ZHW7cyV5mcnZUkB8CGKYEXgb4hde5Qawtehde5AszOb8wuQLwbGCMLfEVkRz74Wn62mZ12x2rGFS0UvXqyy5Zk0iK1Ez6ahmDW53ok34uWPRJoAEBXdp453CMHj5SCFdAoBolaQjzHI34ctuqC21bOD+f53dLNIWwkhGeeY1KjGU= --MP_/bduRHcIgi7cE_At8/bu1uhd Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Disposition: inline Hi Masami, I applied your patches and enabled your ptracingtest code. I noticed that when there's dropped pages, the trace output is not in order: # trace-cmd start -B ptracingtest -e all -v -e '*lock*' # taskset -c 5 echo c > /proc/sysrq-trigger On reboot, I ran: # trace-cmd show -B ptracingtest > /tmp/trace.out Then executed the attached perl program: # ./read-ts.pl < /tmp/trace.out And it errors our: 30.212495 < 30.213534 <...>-1048 [005] d.... 30.212495: irq_enable: caller=irqentry_exit+0xf5/0x710 parent=0x0 That is, I think the zero timestamps may be messing with the order. -- Steve --MP_/bduRHcIgi7cE_At8/bu1uhd Content-Type: application/x-perl Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename=read-ts.pl IyEvdXNyL2Jpbi9wZXJsIC13CgpteSAkbGFzdCA9IDAuMDsKd2hpbGUgKDw+KSB7CiAgICAgICAg aWYgKC9eXHMqXFMrXHMrXFMrXHMrXFMrXHMrKFswLTkuXSspOi8pIHsKICAgICAgICAgICAgICAg IGlmICgkMSA8ICRsYXN0KSB7CiAgICAgICAgICAgICAgICAgICAgICAgIHByaW50ICIkMSA8ICRs YXN0XG4iOwogICAgICAgICAgICAgICAgICAgICAgICBwcmludDsKICAgICAgICAgICAgICAgICAg ICAgICAgZXhpdCAwOwogICAgICAgICAgICAgICAgfQogICAgICAgICAgICAgICAgJGxhc3QgPSAk MTsKICAgICAgICB9Cn0K --MP_/bduRHcIgi7cE_At8/bu1uhd--