From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E034C46CD2 for ; Mon, 22 Jan 2024 22:32:08 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BEF136B0081; Mon, 22 Jan 2024 17:32:07 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B9EBC6B0085; Mon, 22 Jan 2024 17:32:07 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A66596B008A; Mon, 22 Jan 2024 17:32:07 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 945276B0081 for ; Mon, 22 Jan 2024 17:32:07 -0500 (EST) Received: from smtpin25.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 429DC1C133A for ; Mon, 22 Jan 2024 22:32:07 +0000 (UTC) X-FDA: 81708396294.25.7A35BBA Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf24.hostedemail.com (Postfix) with ESMTP id C7F1518001A for ; Mon, 22 Jan 2024 22:32:04 +0000 (UTC) Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=KaXlsHjq; spf=pass (imf24.hostedemail.com: domain of chrisl@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=chrisl@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1705962725; a=rsa-sha256; cv=none; b=XBCAwvmkV7Vh8ChNPq8T9Il7i+0+KacHf5JI3e9itCmKHamqDLyfi869mSOVmxxqW+MQhO 5YUdjOmFRpYt7iyCIr+BuVp70PfUPQwuC5Xrth+zchg07LFwpS1PAHGMAar86qqjnttsip 0Fat2rtQ9ccrqOj81OB1NtEusWS/xvY= ARC-Authentication-Results: i=1; imf24.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=KaXlsHjq; spf=pass (imf24.hostedemail.com: domain of chrisl@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=chrisl@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1705962725; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=wB8nS1L0n8KkReqkQjkPODPnsHa9CM59432Q39H7gps=; b=nd395nrbiPkN1QubrcZXHiS+CGfUB2k3NBfMOTLXio6Omb/TkHRBw4pvhTIMMx5AJtEXq/ VwpB3dr2apx90tSoLioyzd3AFoYM0DapnAkrE6K1gSfBK1DOH/mJVxxZr1bXTXFwrFVS7a 9SaxpcUY0jq5vOH3IBuFyN62zCigVC0= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 609C7CE2D69 for ; Mon, 22 Jan 2024 22:32:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E380C433B1 for ; Mon, 22 Jan 2024 22:32:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705962720; bh=ofMSKFhK198vEBaAAdyZGDEL17Gv+3HRdmRskVVZmhs=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=KaXlsHjq7YSgNa4NvoBuBMiR2XWMa9/8iYk44I1UEaODSgn9wxqjhtrtah13UT/tx 6CHcsbcuW+EwPbnCeHCSAT38qy6ENGrtBLYqM1IeCGbf1U/AIJJFk/rNcZoHQEb8CZ ee7y4Jc3wYpeZ4iCv0TxYb0jiUgRylQnpvpgP3AfmV9Q4RMPy0McUPMLiwigX5hkh4 d3+x5ML3P44HEVir/bVgeywCnJIYTPrPOt1G34cc700tHwYKOAKisO3ct3s5mECfnP dFq+4syZdzzZn8tA3aR9bb0258AUzOJInG4nKb5MEefa9Rv2LGr48AO2Z/OglMMRMf pniEKb+ET3aVw== Received: by mail-lj1-f180.google.com with SMTP id 38308e7fff4ca-2cdeb4b9aa4so42560181fa.0 for ; Mon, 22 Jan 2024 14:32:00 -0800 (PST) X-Gm-Message-State: AOJu0Yxfdn/+5LunJ21VUJyRm5MFeuPoj6zGg6cjhg1HgfOAKTAk6B7R koErxMW1RyHzq91zFB1hW3lMcuHf2Eiu2MbHjAyYcRj/UyMOgg2MMB1Z3Fc07mFwGd+KLDlh6jY soK6z7SnN+ygUZIZT6Qp/2308jA== X-Google-Smtp-Source: AGHT+IHJqbM48hx+HKEh4yWlPV8GWiN1SewFfLmZ6Pj2JL2rUrx960kMMAK7lYnUJ2Z9fXBulsE9a+1No6B3gttTksQ= X-Received: by 2002:a05:651c:19a6:b0:2ce:f8d5:7750 with SMTP id bx38-20020a05651c19a600b002cef8d57750mr1815609ljb.11.1705962718823; Mon, 22 Jan 2024 14:31:58 -0800 (PST) MIME-Version: 1.0 References: <20240120024007.2850671-1-yosryahmed@google.com> <20240120024007.2850671-3-yosryahmed@google.com> In-Reply-To: <20240120024007.2850671-3-yosryahmed@google.com> From: Chris Li Date: Mon, 22 Jan 2024 14:31:46 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 2/2] mm: zswap: remove unnecessary tree cleanups in zswap_swapoff() To: Yosry Ahmed Cc: Andrew Morton , Johannes Weiner , Nhat Pham , Chengming Zhou , Huang Ying , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: C7F1518001A X-Stat-Signature: qj8x75c4sfej6zt4x6g6eedko5qirier X-Rspam-User: X-HE-Tag: 1705962724-571548 X-HE-Meta: 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 vjw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Jan 19, 2024 at 6:40=E2=80=AFPM Yosry Ahmed = wrote: > > During swapoff, try_to_unuse() makes sure that zswap_invalidate() is > called for all swap entries before zswap_swapoff() is called. This means > that all zswap entries should already be removed from the tree. Simplify > zswap_swapoff() by removing the tree cleanup loop, and leaving an > assertion in its place. > > Signed-off-by: Yosry Ahmed > --- > Chengming, Chris, I think this should make the tree split and the xarray > conversion patches simpler (especially the former). If others agree, > both changes can be rebased on top of this. I was wondering why those need to be there if all the zswap entries should have been swapped in already. In my testing I never see this delete of an entry so think this is kind of just in case. Nice clean up and will help simplify my zswap to xarray patch. Thanks for doing this. Acked-by: Chris Li (Google) Chris > --- > mm/zswap.c | 9 ++------- > 1 file changed, 2 insertions(+), 7 deletions(-) > > diff --git a/mm/zswap.c b/mm/zswap.c > index f8bc9e0892687..9675c3c27f9d1 100644 > --- a/mm/zswap.c > +++ b/mm/zswap.c > @@ -1790,17 +1790,12 @@ void zswap_swapon(int type) > void zswap_swapoff(int type) > { > struct zswap_tree *tree =3D zswap_trees[type]; > - struct zswap_entry *entry, *n; > > if (!tree) > return; > > - /* walk the tree and free everything */ > - spin_lock(&tree->lock); > - rbtree_postorder_for_each_entry_safe(entry, n, &tree->rbroot, rbn= ode) > - zswap_free_entry(entry); > - tree->rbroot =3D RB_ROOT; > - spin_unlock(&tree->lock); > + /* try_to_unuse() invalidated all entries already */ > + WARN_ON_ONCE(!RB_EMPTY_ROOT(&tree->rbroot)); > kfree(tree); > zswap_trees[type] =3D NULL; > } > -- > 2.43.0.429.g432eaa2c6b-goog >