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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 93F23C55174 for ; Wed, 5 Aug 2026 09:01:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A01AB6B0092; Wed, 5 Aug 2026 05:01:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9B1E06B00A7; Wed, 5 Aug 2026 05:01:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8C79B6B00AA; Wed, 5 Aug 2026 05:01:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 67E466B0092 for ; Wed, 5 Aug 2026 05:01:31 -0400 (EDT) Received: from smtpin12.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay08.hostedemail.com (Postfix) with ESMTP id DB197140400 for ; Wed, 5 Aug 2026 09:01:30 +0000 (UTC) X-FDA: 85066622340.12.37C7D51 Received: from mail-pj1-f44.google.com (mail-pj1-f44.google.com [209.85.216.44]) by imf19.hostedemail.com (Postfix) with ESMTP id F05791A000B for ; Wed, 5 Aug 2026 09:01:28 +0000 (UTC) Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b=MnT5aHI0; spf=pass (imf19.hostedemail.com: domain of senozhatsky@chromium.org designates 209.85.216.44 as permitted sender) smtp.mailfrom=senozhatsky@chromium.org; dmarc=pass (policy=none) header.from=chromium.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1785920489; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=006EpaNdFPLDBxr2UIddQMK/UW47PHMTajDC95OOpTM=; b=ANoqeJCh9ZrMZLhrXbCkyMlj4FcV12znpUnv6MA2fKGHNk6wpjXZw7+fJTRmMShTbYUPuL yx9mx96BZYVlVljl/aP1DEcGj41VuXIDnEBH+YzEDmbQRLcitVWijpXoW+hZeZqlX2MxHw fgiOuT8mfFzPTEwOMwJL5rWkEIcae5Q= ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1785920489; b=ej8HHbP+5x9I3KdCQRbATuq42xlzIfBB27m7bSekCGNcj5ohYYmoxQzMsKVmGiQMhlyZJt AidNo+uSiJuCgv9xZWBhN6HbDRYCPK9kY2Hh+GKcRiv/16IHmeHldkhnUCizNulE9wIro3 2OOup5+mehz6UOTuObIaFs4wJzomoU4= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b=MnT5aHI0; spf=pass (imf19.hostedemail.com: domain of senozhatsky@chromium.org designates 209.85.216.44 as permitted sender) smtp.mailfrom=senozhatsky@chromium.org; dmarc=pass (policy=none) header.from=chromium.org Received: by mail-pj1-f44.google.com with SMTP id 98e67ed59e1d1-38f0f132f56so1464925a91.0 for ; Wed, 05 Aug 2026 02:01:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1785920488; x=1786525288; darn=kvack.org; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:from:to:cc:subject :date:message-id:reply-to:content-type; bh=006EpaNdFPLDBxr2UIddQMK/UW47PHMTajDC95OOpTM=; b=MnT5aHI0mRtdFa0z3HsmZ4urthbPilK+rL48s/KaI04q3gbs4yODFo8H8EE9CAf1Kf 1DhK7C7y9EjRNPubYNnSjV9cXld1SSh+2fBrFGXgySi/DAAQxJmX0pAICPnIXKfhOpsy 6N89+4WByd9J2kJcizKb5bJmMYoxUvC3DxApE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785920488; x=1786525288; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=006EpaNdFPLDBxr2UIddQMK/UW47PHMTajDC95OOpTM=; b=XUGssfUwc7OwY+DTjLN/bOXUmWb0Zl5ocSdc9LA4tdf4oy/IRPlcQ+7ekOxBUfp4pN PlyoMqlw/mQt6SJxexvd5zc68tIRj6/8mUs0dhmQMaj2+J6YLT0FoC4PkeuCWqrugbve lVwBW0YSbTrTFyGyJTLHzBelBsFwNnO4Fz94Owdis/EWTXo3hIa90IZL80vZezeUXLHv YqLBGuBx4/oXAfGe2GvmlVcecb+EJ2xWuvnEEV2vrmF6PWwgFJPF9HojZDuPvqxkuXE0 MkPNj6p4G157btfSJuZWs8APdT+wojgQjfRJBGbbdIp2B45ZJZFCWYG+RdTrLNWoVWTW kEVg== X-Forwarded-Encrypted: i=1; AHgh+RqEEu6M58IwamKcQ3WGfA/xCp9p0cAUPIxIjyxNnSdPQaVMfSMEjNoXyPqfiD6iP1h5cwxw21nBeQ==@kvack.org X-Gm-Message-State: AOJu0YxclBOHD7zSrCDdH0DOwRRde3wWK6x6wTfLNSYUVkEcwNmv4tov vn6RTQtbQxVDFcazRTD4HkH+KZ52F+FGaNXF8zHkgvxIniOZPIQZ1oPDEZeg6SpYyw== X-Gm-Gg: AR+sD13YdJf/XQXyvzMioW1b/cgNv2er3YQX5kmP3J77CizOCOtYZx7kzNIh3dc/XR2 Mc1PfXWhAMPlEQ+TeDfKT5qBiKXnVeoTo2nF1dGswQ3MlJPIyDkPp0XljBjrqXEd7rHm1nhk87F owWM3LNcd4Ds3gsRqrqqedAZSLaMkb4XFVvwDDwCq8eSQaRd4A0T0bvcHfU9X5weyy0tl4fCt5r KWj7kTNYDX4uxEvwwMaIU+JcBsl79i62xC6K52LoHStoN3QmP2a/daOIBlJ8UOs5HAYu7WvmJWc BLqVBqZY/a3KpjfFIi/BJf+GiCuTUqD7xr89HLVBPuMWVF6LmrdqlGo9hpQlTNyz1rAMhYxYRq+ 2lrry5jQN8yzmDAoKlUeVH/JKll0BpUMqEa0xb99ocT91wkfYwG0le17XbQubY/FIMcl4xFjAQE Kp/nMSht5cKv9pqCeihPAw2oa7gz3p/OLrXn2Gm5Jm2W5HxFe5/MkKH75QggUk40fv2nIYhAae9 ViRfQLFi/d0Vbb6VbYKPauhzJ30 X-Received: by 2002:a17:90a:d44f:b0:37f:9e21:91d6 with SMTP id 98e67ed59e1d1-3903c6287bbmr2193012a91.13.1785920479816; Wed, 05 Aug 2026 02:01:19 -0700 (PDT) Received: from google.com ([2a00:79e0:2031:6:8002:2a47:a704:5a58]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-38fedc650a0sm3967542a91.14.2026.08.05.02.01.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 05 Aug 2026 02:01:19 -0700 (PDT) Date: Wed, 5 Aug 2026 18:01:14 +0900 From: Sergey Senozhatsky To: Sergey Senozhatsky Cc: Barry Song , akpm@linux-foundation.org, bigeasy@linutronix.de, hdanton@sina.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, minchan@kernel.org, ryncsn@gmail.com, yosry.ahmed@linux.dev, surenb@google.com, Dongdong Zhang , Suleiman Souhlal Subject: Re: [RFC PATCH] zram: avoid preemption with CPU-based compression backends Message-ID: References: <20260805005545.66112-1-baohua@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam07 X-Rspam-User: X-Stat-Signature: a5eueus7rjko7cjbxsk1csk3xg7yekwf X-Rspamd-Queue-Id: F05791A000B X-HE-Tag: 1785920488-710239 X-HE-Meta: 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 x5jePHqc 11pgWOaoeTy51UVoaLEKYbvgilidXZd9tZjTFD/9w+4N0nX+iolOrt+ONPe65kYevW70qMt1Kk6S27SGmYbdGkkICLpNBEdr3Hc7P8PxfKHU4Cnw6Lwe81K/8WG4sp1PhEgXfbaUguxkJCzvSeae+ZMf82nvl7liqwYpY1CRfXlx78tVYkMVp/wenMTMGU5qTaKhN8iClPi9r4GCsiUTI8ptR7xwDXMaNBj1EzOfaHIFkhayTpTJwdwP5GPQyO1rcg++C0jgNKjPp9h6H/GVVy/gY1afgfbuShQr2QBXK4kvDpB8zX4Z7IMmxPJVyA+8+PstsGSNUhdxDgR6tlfH0Zt3s82XepbQLrmq2Iizc873/eTY= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On (26/08/05 17:46), Sergey Senozhatsky wrote: > On (26/08/05 15:50), Barry Song wrote: > This sounds interesting. I think all of the S/W backends that we use > have stateless decompression OK, that doesn't seem to be true, but just for initial testing on lzo/lz4 we can simply split the lock. zstd/deflate need context for decompression, this doesn't look stateless.