From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) (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 CCF643502B5; Wed, 7 Jan 2026 16:10:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.13 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767802219; cv=none; b=Hwjau43MbN1R8dEeaqU4OaNQLxxIOlYDcWE+c7DQZ+LZm6BrbHsWIaXZfdovjsyA0+mMFSwVnwrfZfsfPYZOMi3KlYxYCDU0v+92p03wGIJJdzt8qhjTWDJGwWiEsfd/DtrozUL0Fg/nur4u8/cUUxsCs8Tt77G92EVqGFV371g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767802219; c=relaxed/simple; bh=v4xyIC/PxCWb8QaKeYiX/JdahNMf2rBuSomOIgoNSmQ=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=LWWqqQ3Fd/U0r4ice5wF47JagfBImK9U5c7LTY+vj+FTg/w55GtXogVZx95yJWuYalzyVOZA64FCOuFbG/9+kYd5Z3TzltmKiA1AblBLdU5nDomAfhPHNZ368sdegNgp6ya+7D5gnH7KC/un59zR+uUPz9HNUqoYO7pXLkoLgtc= 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=216.40.44.13 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 omf04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 65CB31AAD5F; Wed, 7 Jan 2026 16:10:05 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf04.hostedemail.com (Postfix) with ESMTPA id DA1A12002D; Wed, 7 Jan 2026 16:10:02 +0000 (UTC) Date: Wed, 7 Jan 2026 11:10:29 -0500 From: Steven Rostedt To: Breno Leitao Cc: Mark Rutland , Catalin Marinas , Will Deacon , Laura Abbott , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Masami Hiramatsu , kernel-team@meta.com, puranjay@kernel.org, stable@vger.kernel.org Subject: Re: [PATCH v2] arm64: Disable branch profiling for all arm64 code Message-ID: <20260107111029.28e0c52b@gandalf.local.home> In-Reply-To: References: <20260106-annotated-v2-1-fb7600ebd47f@debian.org> <20260106111142.1c123f12@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-Stat-Signature: khippqaiyx8cd5m1dse5kww4arzqhpxh X-Rspamd-Server: rspamout01 X-Rspamd-Queue-Id: DA1A12002D X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX186ZkSD32iPpRx5ow4Xmjt+UAgCjzMt04s= X-HE-Tag: 1767802202-773670 X-HE-Meta: U2FsdGVkX19vKCXb5K+qpusqOqSjw8DJI3OWGz/LwzFg+F+VEV1dTBh8MA6eTmVsqAqy8P1lCIp7g8VSiwdNyXJjA4k+cwHYlU7CJMArTtnVhzZ3IS59JSgTxf/pcV2CD9mQ1DrzxMjnApWld23yV0xKpCfnvlZXe0bAskSnFshPdP05mS3lJ9ddA2RDCsU5Wx7+v/t84oEnQkGzpG1lAZ+yxThfxovX52OJgA6WTBBWjWgtq698VQxEcteo9G7Az+M19vhLRRv2bZvYgTPGqs1UPWdTP4oQGu2IXrCgTeWgUgCiQv4sevX86v+/U2CLaAKbrKzqDAaYwrGGd7UCLgp4R2muFF2gJuFDYEwHtDtmgQ/2a1TTbw== On Wed, 7 Jan 2026 01:37:36 -0800 Breno Leitao wrote: > I am starting to look and remove some of these likely/unlikely hint that > are 100% wrong on some very sane configuration (arm64 baremetal hosts > running a webserver). > > So far, these are the fixes I have in flight now. > > * https://lore.kernel.org/all/20260105-dcache-v1-1-f0d904b4a7c2@debian.org/ > * https://lore.kernel.org/all/20260106-blk_unlikely-v1-1-90fb556a6776@debian.org/ > * https://lore.kernel.org/all/20260105-annotated_idle-v1-1-10ddf0771b58@debian.org/ Nice. Thanks for letting me know. I'm happy to see that someone besides me is using the annotated branch profiler to fix real issues in the kernel. I would love it if more people did the same. Anyway, please advertise this as much as possible. If it shows that it is helping to fix real bugs, maybe it would attract the interest of more developers, and more importantly, it keeps the tooling in place. I'm constantly fighting to keep it from being removed from the kernel :-p -- Steve