From nobody Mon Sep 15 00:13:19 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6C6DCC00A5A for ; Wed, 18 Jan 2023 01:03:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229889AbjARBDF (ORCPT ); Tue, 17 Jan 2023 20:03:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53920 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229635AbjARBCL (ORCPT ); Tue, 17 Jan 2023 20:02:11 -0500 Received: from mail-pl1-x62a.google.com (mail-pl1-x62a.google.com [IPv6:2607:f8b0:4864:20::62a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F0DFB53E63 for ; Tue, 17 Jan 2023 16:52:28 -0800 (PST) Received: by mail-pl1-x62a.google.com with SMTP id jl3so233535plb.8 for ; Tue, 17 Jan 2023 16:52:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=wlEuvLJ1OIwhsVr6jP4j+nVp1P/tzWBP4lAYnG/eYgY=; b=TLu9c0Cj9B2z19rRraJKbiywIrmYs/BVdE12dMxlvW8Y149yooSO39yxohc5u8cq2d iUC1z81ahFo78NQK8aD1I9A9YnnL2f69pBet4g2EhZAiqQHWUM3UP/Cm/nQMw5XYJU1D himUcbF+wJEhI9kS2XeqnPuGlUxxUFPHNZCXQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=wlEuvLJ1OIwhsVr6jP4j+nVp1P/tzWBP4lAYnG/eYgY=; b=cHVPa+DUHoTThxVUqPSes177OJAelT2UzQ5+qOqEpDpAVmTpTnonIfmqtFG27E+z5s IYXgkAALEYHMUa5t1xgQNegCgoDlijdgrXk9ssp4TCR3ZLnT2Poylazg4WqHqWeUrjEe uGBZ1dIXiS5XEhnn5TGLi9TzTgyaISPRWmf0bBSvHSvsLtoepXldYspNyltL2lfcSIhQ 7aQTFYGxZSEiiFxPfQyN5AShpECIik5E4j6BY0jB7MC6n2WeiOOPuynh8fZSfIHygLEJ cxe8D9c5xV/8JA9BCgIB9VQ4MWcWe6Z07XyQ+sdHnC0jUkziA7y2qnaWsxqDZCdBcUSF yDEw== X-Gm-Message-State: AFqh2koiKouAwK9zod40noTQ22SiOJkXDPVAINOP7t5ciAslptT4Syvl EOhcA8rJGeIpnz19l2dXUAHrXw== X-Google-Smtp-Source: AMrXdXvg3Wmcxlr+zxIzbctf0szk1Alr8VFtzl74qmArJYWCAlwZt9atsHWVsv5Y4QATS8R33CZw/w== X-Received: by 2002:a17:902:8d94:b0:192:d9dd:167d with SMTP id v20-20020a1709028d9400b00192d9dd167dmr4633379plo.43.1674003146107; Tue, 17 Jan 2023 16:52:26 -0800 (PST) Received: from tigerii.tok.corp.google.com ([2401:fa00:8f:203:10f3:73a5:7e44:adbf]) by smtp.gmail.com with ESMTPSA id u10-20020a17090341ca00b00192f4fbdeb5sm8351461ple.102.2023.01.17.16.52.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Jan 2023 16:52:25 -0800 (PST) From: Sergey Senozhatsky To: Andrew Morton , Minchan Kim Cc: Mike Kravetz , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Sergey Senozhatsky Subject: [PATCHv3 2/4] zsmalloc: skip chain size calculation for pow_of_2 classes Date: Wed, 18 Jan 2023 09:52:08 +0900 Message-Id: <20230118005210.2814763-3-senozhatsky@chromium.org> X-Mailer: git-send-email 2.39.0.314.g84b9a713c41-goog In-Reply-To: <20230118005210.2814763-1-senozhatsky@chromium.org> References: <20230118005210.2814763-1-senozhatsky@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" If a class size is power of 2 then it wastes no memory and the best configuration is 1 physical page per-zspage. Signed-off-by: Sergey Senozhatsky Acked-by: Minchan Kim --- mm/zsmalloc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index effe10fe76e9..ee8431784998 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -2287,6 +2287,9 @@ static int calculate_zspage_chain_size(int class_size) int i, min_waste =3D INT_MAX; int chain_size =3D 1; =20 + if (is_power_of_2(class_size)) + return chain_size; + for (i =3D 1; i <=3D ZS_MAX_PAGES_PER_ZSPAGE; i++) { int waste; =20 --=20 2.39.0.314.g84b9a713c41-goog