From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 96E493B3C01 for ; Fri, 10 Apr 2026 09:06:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775811988; cv=none; b=CrLPRZCTc9ORD9JB0tQDnRi/WPR7+H+/YIEoDtC4x/9F19TeTxU7mMI0PbHjTagLjMeRmyQERFmTj7QLQRrxgQG94MXNPgSXGXU4GfWO5Ee2VuswPjn066Ww2/+WD9yWWdd90VBWceEZjEsnmwc2byWbP16dDrCruMxy34Tbj1w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775811988; c=relaxed/simple; bh=r6/xbm9ICEZLdIhlJPxwO6tzE4dSTQazY+YvqBBoM2k=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=pRNY0X01wd2ajjFAlaOyIMcuLqJkr5PLdGKcoF/afOaMyL+n9Tt+ubNpWo9k0J2n1s5NIVMlc4xglVqJG1JKuGpWXK6LWNYBOaOoFYXS6Kh3b5M81ztXgaQyPoIqkP4w82xmTFQcr9/Y2oHp6TRgJF0sSLdaS+jP/8xx6xFki+Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eos85lOv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="eos85lOv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B66FCC19424; Fri, 10 Apr 2026 09:06:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775811988; bh=r6/xbm9ICEZLdIhlJPxwO6tzE4dSTQazY+YvqBBoM2k=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=eos85lOv5ieVGVViyeV9H30S6rhaZ66FfCRd2srlJqSdzBHLl0WBvPWL6r9yOs2r5 To3G6fQX1vq9l0WTRVqnxL+X42bA83wlV//sl5G8/n062fFsAAJj15qh0o6LIKNqNp DqtVbDWrg+DY7LZ7QB2TUPxy0mCX53IvR5t63iatip4XaImexBLFdZ3wO2TaK91Knr 5feVfe+iwBC6EydkqVk4Oi8hen+UcAJvn7tR3QYmlxB/XWGVW7o3u4tjySeuUa8T3o 37a5hRNfOrNChzlIhnRdzJoW6x7UHrHjXFuoh0cwDnPZqUSyqkF8yAKcD8/iYhrUa4 aTk5qMMxPuo0A== Message-ID: <51c35e9f-fda6-4a24-acf5-8a332dd505d8@kernel.org> Date: Fri, 10 Apr 2026 11:06:23 +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 v3 2/2] ksm: Optimize rmap_walk_ksm by passing a suitable address range To: xu.xin16@zte.com.cn Cc: shr@devkernel.io, ljs@kernel.org, hughd@google.com, akpm@linux-foundation.org, chengming.zhou@linux.dev, wang.yaxin@zte.com.cn, michel@lespinasse.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260410160600883wV0ynx9z59eSt4_lOUFfK@zte.com.cn> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit > It looks confusing indeed, but it does break_cow because when merging two pages into > one KSM, the first one succeeds but the second one fails, so it's necessary to > restore the state of the first successful rmap_item. > >> So we might want to reset the pgoff there as well, OR only store >> the pgoff in stable_tree_append() where we actually set STABLE_FLAG. >> > > Yes, I agree. Please allow me to reorganize all the key points we've discussed, and > update and optimize the patch along with the test program. Sure, let me know if I can help. > > I will try to release v4 for review as soon as possible Yes, no rush. Merge window is about to open, so we have 2/3 weeks where nothing new will get merged either way. -- Cheers, David