From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 1120C435EC0 for ; Wed, 8 Jul 2026 16:32:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783528348; cv=none; b=FhGPHhL7ncWsOPpH+oelfQ41/7QsSwze1A3KDyU5Nda+H7GX2iesG5tDUKZzmRiSKeb61nyNjBojESieThJGK4DHVBFMOzAvjjNb9G8KtAHkFYs0CfquCDsmYqoZQFaUnwlHClF1VtCmIjXYzLuMayPeyPTR/2VyS90cboNXUYA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783528348; c=relaxed/simple; bh=jrqpTXbCTGnkVHnIO6vYCWHi1Nyi74lPA/TH8sCTnuY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=CS7wGasjM3KW7YofETzhk/yuFFhz2aMfJi/oB4TqwnpoSlDBDPIB4MAWPBoC7CF597WNFzPufSApPAXYXhmPxitF/ns48ZiQ1huUSEc6S7e4qLdzxTdF3Ji8I/WSGtEtMQ3nW3Lc3f/twJpJnq/syMGhU5QgWLyao23qcDbNC8o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WNVYon2c; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WNVYon2c" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DC4C31F000E9; Wed, 8 Jul 2026 16:32:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783528346; bh=P6tPxX3gIMIVPqjzkXAtg0q2TsTgXMBwoII0aWUrcyo=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=WNVYon2c7VTFWQGDORJfI135bNGLrZIyVS6PYqzKr0T52GWoSlkdZW7KTnKd6u/r+ TquGsv01GkbqExIbNU96vxAvvqK15dFlp1rNJhY7y/obqQ6eOjIOHFMX+cW8CJ8Wim McUk4ej/jiRea1PcZG6s3NqkcstFCNUZ95wzKd21r7FBDS8zMv+afGINi/geYMo5xk Tp7cOYsfec2EWV2P8Gyi5SwUk9pKzLmkxRooB4pbRUgMwMDwCmp4rSi8llR9zb4opd za79X6/+7vF/W+n5s09mFuut7FFQRXn64MYP2mv8BJifTqziEGrbsliRY6yCyxfuUn sE5Y2awZoVtUA== Message-ID: Date: Wed, 8 Jul 2026 18:32:23 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] mm/slab: extract __free_to_pcs_batch() from free_to_pcs_bulk() Content-Language: en-US To: hu.shengming@zte.com.cn Cc: harry@kernel.org, akpm@linux-foundation.org, hao.li@linux.dev, cl@gentwo.org, rientjes@google.com, roman.gushchin@linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260707233433577tAGELJALunrdd2lZy83V-@zte.com.cn> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/7/26 17:34, hu.shengming@zte.com.cn wrote: > Vlastimil wrote: >> It has been noted that free_to_pcs_bulk() is difficult to follow, with a >> number of goto labels, and this has contributed to two memory leak bugs >> in there. >> >> Extract part of the code to __free_to_pcs_batch(), which focuses only on >> freeing free-hook-processed local objects to a percpu sheaf, and >> returning how many were freed. Zero means a trylock failure or no empty >> sheaf available, and thus the caller should fallback to >> __kmem_cache_free_bulk(). >> >> Make free_to_pcs_bulk() call this in a while loop, removing all goto >> labels from the function. __free_to_pcs_batch() retains two rather >> straightforward ones. > > Hi Vlastimil, > > This looks like a very nice refactoring to me. Splitting out the actual > per-CPU sheaf batching into __free_to_pcs_batch() makes the control flow > in free_to_pcs_bulk() much easier to follow, and also keeps the fallback > handling clearer. > > Please feel free to add: > Reviewed-by: Shengming Hu Thanks! Added to slab/for-next