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 5CEB8C02181 for ; Wed, 22 Jan 2025 16:47:24 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E268A280002; Wed, 22 Jan 2025 11:47:23 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id DDFED280001; Wed, 22 Jan 2025 11:47:23 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C7661280002; Wed, 22 Jan 2025 11:47:23 -0500 (EST) 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 A771E280001 for ; Wed, 22 Jan 2025 11:47:23 -0500 (EST) Received: from smtpin08.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 25B74120446 for ; Wed, 22 Jan 2025 16:47:23 +0000 (UTC) X-FDA: 83035668366.08.A258129 Received: from mail-wr1-f41.google.com (mail-wr1-f41.google.com [209.85.221.41]) by imf23.hostedemail.com (Postfix) with ESMTP id 327C0140002 for ; Wed, 22 Jan 2025 16:47:21 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=joelfernandes.org header.s=google header.b="ewcB5/3H"; dmarc=none; spf=pass (imf23.hostedemail.com: domain of joel@joelfernandes.org designates 209.85.221.41 as permitted sender) smtp.mailfrom=joel@joelfernandes.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1737564441; a=rsa-sha256; cv=none; b=VW7+5PiJpy+wyTNFjW96rKbMJUM16GeulYVq/WLqgHGjsr5LchdUN43w4wWpiPpgdMcSl5 ea+EGkF6lvbUefDQaaPDJa1HYvMkHhU3HowmoM05HNNoJPx+HgBvF2BOyvOlvrRSCkivf1 t3X+7CWclHb7QRnrlTCfAG95KKkvl3Y= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=pass header.d=joelfernandes.org header.s=google header.b="ewcB5/3H"; dmarc=none; spf=pass (imf23.hostedemail.com: domain of joel@joelfernandes.org designates 209.85.221.41 as permitted sender) smtp.mailfrom=joel@joelfernandes.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1737564441; 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=c7eNrYhn25OshZ5MoLVjVOHUVd5m0omckevSdNUfGuU=; b=lMSZPttrNW3b06BmCat9PwF+JIIIxF/EFzKCx8WofmRQbyMVrRNYknITROMtnuXHXHENcb Df9d++ZIb0ek2ErWxC+Z7IQATYirPqF7nZhepxAE+xzB75EkzM0jdbP6RFkJX6wRGV4ZtQ BQpY9vQ1k/AY0Bnx3duv5S2ILwfnk0w= Received: by mail-wr1-f41.google.com with SMTP id ffacd0b85a97d-385de9f789cso5398572f8f.2 for ; Wed, 22 Jan 2025 08:47:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; t=1737564440; x=1738169240; darn=kvack.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=c7eNrYhn25OshZ5MoLVjVOHUVd5m0omckevSdNUfGuU=; b=ewcB5/3HLAFfpRpq5Wl8IeYVyiMYDEMmgP/etdJMHSzFxSOuj5vN0u6lqk9QwLuGPK 7PFweY/tc8hq9ej2u4cTe45sm6CnY/7+7XrMQq9kY+94j6DBdvX4HDTXriKhQX4JOFjy rEaST+4VjIwncgZRyR9wOu7E5NL4stpysGNOA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1737564440; x=1738169240; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=c7eNrYhn25OshZ5MoLVjVOHUVd5m0omckevSdNUfGuU=; b=lCnFaf47oaLOGv2Xgq0SAHt4kaSIBsjOrgHrGZ6q/iQQP9ZDm7vbcnOZRG5tNOP8H9 H55j2cIljZaaiqO8MVexmt+ZmfMEmIsCwtB079zh0dpyUZ0c62xNDwZzR7fE31szs8vS jZQ6J8FPSFmVxr1u0rS5pB6lAkro7yAcsC3ukKebVKAV7V1juHJT0fx12PpVGu0KacVK MMyKuoWtPfQqZNk+UzImZ9KXbq1naG5jOW4isNoiBTdPDHf/Po74wcvKO/hyCH951RNR PiPj8RGbU9ShFsFMISKCiHoQCZKL1Z7HbsNJpVBcxcRSChbNCsE199wPf4/GQos3Ku93 LvMw== X-Forwarded-Encrypted: i=1; AJvYcCU144mHP+nBAt0yHt5cNz2jTuiYrj1Gccii1spKk8TdA8XXts22RqjNxyIpsnskvr3FdvARqAr0rA==@kvack.org X-Gm-Message-State: AOJu0YwoMFBlxdf7CcegDuHSCv6oIOlabd81fEEbLn3bVrJlh8w2zb/5 oRPjdyolRZv3H2qcon+dXjD2CT0s05+Jh3TneN6FQGeE6sG2gl8q1m6xxEanJdzP33bUYyKx7/9 mcBoQBQ3Anzln0VcjnN1kxgeri8bVcoSoB6roHg== X-Gm-Gg: ASbGncvsiZccWYELz4E/lIfvnbW4rhiePzIEWMzo0SZgzTcu1itsPuv6FGECmohseE7 j/FIleXCk0rFLIJ82tjz92iStRiO5WpJAzp7SpxXaFGt3IoCDSB0= X-Google-Smtp-Source: AGHT+IHJbf8ZuP6VbD9mw8MFzQIXmfmvyiLE2uMOLNmlpOLxtqeXh2VdUGTpX6n5lz5lzjHhE/ZOIe2e2J8nWACu7Ho= X-Received: by 2002:adf:f249:0:b0:38a:4b8b:295a with SMTP id ffacd0b85a97d-38bf5673c40mr15605854f8f.31.1737564439560; Wed, 22 Jan 2025 08:47:19 -0800 (PST) MIME-Version: 1.0 References: <6fb206de-0185-4026-a6f5-1d150752d8d0@suse.cz> <5bb80786-220d-45d2-bd35-51876df4203c@paulmck-laptop> <55931fdd-1d5f-4ffd-8496-fe436171dee2@suse.cz> <970317a9-0283-4eec-94ae-63056659d7de@suse.cz> <7b7b92a3-780e-4db0-a5cf-3e78d79587a2@paulmck-laptop> In-Reply-To: From: Joel Fernandes Date: Wed, 22 Jan 2025 11:47:05 -0500 X-Gm-Features: AWEUYZlETxKJWiDbnpK2ioAdVP_NeMgDGl1i_cppI7gm2Xv6v12c1mBpXnsjxt8 Message-ID: Subject: Re: [PATCH v2 0/5] Move kvfree_rcu() into SLAB (v2) To: Vlastimil Babka Cc: paulmck@kernel.org, Uladzislau Rezki , linux-mm@kvack.org, Andrew Morton , RCU , LKML , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, Oleksiy Avramchenko Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Queue-Id: 327C0140002 X-Rspamd-Server: rspam10 X-Stat-Signature: qnnfe9r4fpie5pf7f75a9515cbghqsdu X-HE-Tag: 1737564441-216607 X-HE-Meta: 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 uLsAX5+E YR/Gi+YKJ5w4JU8nwgf8kszZLI1mN0do1i1Uzkg03BBdr3JDDPiD9bkjJI8SzXwr+eKBcHtj3V5f0ocURTO7cxltVAtvvyZFmWtRjzljcUwGDjX7tjlo902but+h9AigkhlU5jWwdjA6tF1f6WgTlFxBuzZitMKLc8ffckLMViMnoeAJU5zsoK0cu/Xmlssh62tDWtFqeLIqd6/tFRph0blc56G+Mla8cj35zyVQHDE49DbeUaAe4fm/6IjM77Qj2VEkjtS7doDjSgdK/nUaPGil7tAXTgPY6vQs4mx+ZUbtRlfq5d/NPHYN48Q== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000013, 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 Wed, Jan 22, 2025 at 11:43=E2=80=AFAM Vlastimil Babka w= rote: [...] > > __is_kvfree_rcu_offset() and its usage from Tiny. Granted, there is > > the overhead of function calling, but I highly doubt that it is going > > to be a bottleneck, considering that the __is_kvfree_rcu_offset() path > > is a kfree slow-path. I feel in the long run, this will also be more > > maintainable. > > > > Or is there a reason other than the theoretical function call overhead > > why this may not work? > > My concern was about the overhead of calculating the pointer to the objec= t > starting address, but it's just some arithmetics, so it should be > negligible. So I'm prototyping this approach now. Thanks all. Ah, that's a valid point. Looking forward to reviewing the patch and hope it works out! thanks, - Joel