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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 098B1C47DA7 for ; Tue, 16 Jan 2024 21:00:15 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=chrisdown.name header.i=@chrisdown.name header.a=rsa-sha256 header.s=google header.b=pQjJ87Ew; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4TF1cG4cXZz2ykx for ; Wed, 17 Jan 2024 08:00:14 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=chrisdown.name header.i=@chrisdown.name header.a=rsa-sha256 header.s=google header.b=pQjJ87Ew; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=chrisdown.name (client-ip=2a00:1450:4864:20::32a; helo=mail-wm1-x32a.google.com; envelope-from=chris@chrisdown.name; receiver=lists.ozlabs.org) Received: from mail-wm1-x32a.google.com (mail-wm1-x32a.google.com [IPv6:2a00:1450:4864:20::32a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4TDvxs0Rvdz2ysD for ; Wed, 17 Jan 2024 03:45:02 +1100 (AEDT) Received: by mail-wm1-x32a.google.com with SMTP id 5b1f17b1804b1-40e69b31366so37911625e9.1 for ; Tue, 16 Jan 2024 08:45:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chrisdown.name; s=google; t=1705423497; x=1706028297; darn=lists.ozlabs.org; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=zfgzSOT5YsRlYZszh8CGN3Yrxu5fn/m7q+vPcIoOkRo=; b=pQjJ87EwgMqjEpRIII8i3ZL2AeyNolAREcqD1hBUEPUDbdDVGmzCtXFsGjYYwGd/I1 g+lWAFbJclk6wPQWAdLUes6o2BsdMlpY0O78X6D7EBPvIQt8VJO+OTItFCS4zk0kreMk BaR/6/JOK5Kuus9G4apRlfzAFCXr/r0Egzf50= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705423497; x=1706028297; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=zfgzSOT5YsRlYZszh8CGN3Yrxu5fn/m7q+vPcIoOkRo=; b=vOEs1YZGcdf6tkla5NNSfBngZibKJfDm5VjEGew7C7uEsdw5Uil55cEM5magvr9z+2 /T51dIL+AsWQVD68IK0jMQcc3glgNZvtBRsG2Y9ok02rJf10Znmw6eXTbNlzWzgRO4hn KyJR+tl17+pkH3AkjWvzeXKWEkTTOmQOZ7kai1LhsfltaG/46vWs1ins8Bd35jxzmftc iMQ4wH3Dhhmm5U0P8tbJ1NWQS+Nei6Py5ITt3cU2j3oLzmRCyuVgbe1JpzmmMS2VLPwj huefbVrvb+EY+DHITC5RwQdofpCxC9NF453W7wYezwAd7BhHC3c/+jWAmDkN6H/uP4ab Jjvw== X-Gm-Message-State: AOJu0YxW2BQqnNDOdbj285Vyx9+ZXtZmvLvpLzxfOBkEe4IWEB+NwJij TQ17EMq5EMV7FCa4CuDYw3jZ6r3RYRD/Ig== X-Google-Smtp-Source: AGHT+IGLlTqH9WZOC/OME4zoyjXAaxL4iv39bxZRTYkDmE8GGBdCKiSNb+tybKwAFnn9zCLTCDPSJg== X-Received: by 2002:a05:600c:4d1f:b0:40e:5b54:1f6e with SMTP id u31-20020a05600c4d1f00b0040e5b541f6emr3393949wmp.131.1705423496977; Tue, 16 Jan 2024 08:44:56 -0800 (PST) Received: from localhost ([2a01:4b00:8432:8600:5ee4:2aff:fe50:f48d]) by smtp.gmail.com with ESMTPSA id je6-20020a05600c1f8600b0040d8d11bf63sm19929191wmb.41.2024.01.16.08.44.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Jan 2024 08:44:56 -0800 (PST) Date: Tue, 16 Jan 2024 16:44:55 +0000 From: Chris Down To: Yosry Ahmed Subject: Re: [RFC PATCH] mm: z3fold: rename CONFIG_Z3FOLD to CONFIG_Z3FOLD_DEPRECATED Message-ID: References: <20240112193103.3798287-1-yosryahmed@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20240112193103.3798287-1-yosryahmed@google.com> User-Agent: Mutt/2.2.12 (2023-09-09) X-Mailman-Approved-At: Wed, 17 Jan 2024 07:59:26 +1100 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Miaohe Lin , Nhat Pham , Huacai Chen , Nicholas Piggin , "Aneesh Kumar K.V" , linux-mm@kvack.org, loongarch@lists.linux.dev, Johannes Weiner , "Naveen N. Rao" , Andrew Morton , linuxppc-dev@lists.ozlabs.org, WANG Xuerui , Vitaly Wool Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Yosry Ahmed writes: >The z3fold compressed pages allocator is not widely used, most users use >zsmalloc. The only disadvantage of zsmalloc in comparison is the >dependency on MMU, and zbud is a more common option for !MMU as it was >the default zswap allocator for a long time. > >In hopes of having a single compressed pages allocator at some point, >and following in the footsteps of SLAB, deprecate z3fold. Rename the >user-visible option so that users with CONFIG_Z3FOLD=y get a new prompt >with explanation during make oldconfig. Remove CONFIG_Z3FOLD=y from >defconfigs. > >Existing users, if any, should voice their objections. Otherwise, we can >remove z3fold in a few releases. > >Signed-off-by: Yosry Ahmed Acked-by: Chris Down Thanks. We are definitely hurting users as well by keeping this around with its known issues when writeback is disabled, for example. >--- >I have limited understanding of Kconfigs. I modelled this after commit >eb07c4f39c3e ("mm/slab: rename CONFIG_SLAB to CONFIG_SLAB_DEPRECATED"), >but one difference is that CONFIG_Z3FOLD is a tristate. I made >CONFIG_Z3FOLD_DEPRECATED a boolean config, and CONFIG_Z3FOLD default y >so that it is on by default if CONFIG_Z3FOLD_DEPRECATED is selected. I >am not sure if that's the correct way to do this. > >--- > arch/loongarch/configs/loongson3_defconfig | 1 - > arch/powerpc/configs/ppc64_defconfig | 1 - > mm/Kconfig | 13 +++++++++++-- > 3 files changed, 11 insertions(+), 4 deletions(-) > >diff --git a/arch/loongarch/configs/loongson3_defconfig b/arch/loongarch/configs/loongson3_defconfig >index 33795e4a5bd63..89b66b6c6a1d5 100644 >--- a/arch/loongarch/configs/loongson3_defconfig >+++ b/arch/loongarch/configs/loongson3_defconfig >@@ -85,7 +85,6 @@ CONFIG_ZPOOL=y > CONFIG_ZSWAP=y > CONFIG_ZSWAP_COMPRESSOR_DEFAULT_ZSTD=y > CONFIG_ZBUD=y >-CONFIG_Z3FOLD=y > CONFIG_ZSMALLOC=m > # CONFIG_COMPAT_BRK is not set > CONFIG_MEMORY_HOTPLUG=y >diff --git a/arch/powerpc/configs/ppc64_defconfig b/arch/powerpc/configs/ppc64_defconfig >index 544a65fda77bc..d39284489aa26 100644 >--- a/arch/powerpc/configs/ppc64_defconfig >+++ b/arch/powerpc/configs/ppc64_defconfig >@@ -81,7 +81,6 @@ CONFIG_MODULE_SIG_SHA512=y > CONFIG_PARTITION_ADVANCED=y > CONFIG_BINFMT_MISC=m > CONFIG_ZSWAP=y >-CONFIG_Z3FOLD=y > CONFIG_ZSMALLOC=y > # CONFIG_SLAB_MERGE_DEFAULT is not set > CONFIG_SLAB_FREELIST_RANDOM=y >diff --git a/mm/Kconfig b/mm/Kconfig >index 1902cfe4cc4f5..bc6cc97c08349 100644 >--- a/mm/Kconfig >+++ b/mm/Kconfig >@@ -193,15 +193,24 @@ config ZBUD > deterministic reclaim properties that make it preferable to a higher > density approach when reclaim will be used. > >-config Z3FOLD >- tristate "3:1 compression allocator (z3fold)" >+config Z3FOLD_DEPRECATED >+ bool "3:1 compression allocator (z3fold) (DEPRECATED)" > depends on ZSWAP > help >+ Deprecated and scheduled for removal in a few cycles. If you have >+ a good reason for using Z3FOLD rather than ZSMALLOC or ZBUD, please >+ contact linux-mm@kvack.org and the zswap maintainers. >+ > A special purpose allocator for storing compressed pages. > It is designed to store up to three compressed pages per physical > page. It is a ZBUD derivative so the simplicity and determinism are > still there. > >+config Z3FOLD >+ tristate >+ default y >+ depends on Z3FOLD_DEPRECATED >+ > config ZSMALLOC > tristate > prompt "N:1 compression allocator (zsmalloc)" if ZSWAP >-- >2.43.0.275.g3460e3d667-goog > >