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 B8F47C28B30 for ; Fri, 21 Mar 2025 03:32:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BF6AF280002; Thu, 20 Mar 2025 23:32:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id BA755280001; Thu, 20 Mar 2025 23:32:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A6FED280002; Thu, 20 Mar 2025 23:32:37 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 8A186280001 for ; Thu, 20 Mar 2025 23:32:37 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id CAE041CDB8E for ; Fri, 21 Mar 2025 03:32:38 +0000 (UTC) X-FDA: 83244135996.27.101988B Received: from mail-wm1-f42.google.com (mail-wm1-f42.google.com [209.85.128.42]) by imf30.hostedemail.com (Postfix) with ESMTP id 150A78000B for ; Fri, 21 Mar 2025 03:32:36 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=DjRrTr5W; spf=pass (imf30.hostedemail.com: domain of alexei.starovoitov@gmail.com designates 209.85.128.42 as permitted sender) smtp.mailfrom=alexei.starovoitov@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1742527957; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding:in-reply-to: references:dkim-signature; bh=g9oozaQPCiW7aHMMJLEoWbHIJA+eqbljpGWao3hp29Y=; b=qq6fF7tqTHDDQIASyyExb2F3c8OW3D5+d56E5EZ4zhy2uglGnG6BkjLmIS6fhbYipwOdKQ PptZBtAlSgw7tYqtK9oDfdPgjeTYFdYs7zPFaRA0ciiYru0dcIc6Ykeaurwn/eobSO9hpo nMEpgMnYp0ny9gd7TxzuO+kgO5JPzYE= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1742527957; a=rsa-sha256; cv=none; b=4dsP9VDL/Nr1cjCyZxb0loUjyYto/Wx5sT69ABUwpC1VdY7+osiYBujLxcV26sYs8A1Z8g LHGYYJiTJ1FN5EefILJyrgh5j37LtxSlwcRmHOY2HVg1KIGgTlF6gzr/0dG3l6c5/hOYwu ed+n3xbmjKj3Aa27ApI60Vv6EaviLJg= ARC-Authentication-Results: i=1; imf30.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=DjRrTr5W; spf=pass (imf30.hostedemail.com: domain of alexei.starovoitov@gmail.com designates 209.85.128.42 as permitted sender) smtp.mailfrom=alexei.starovoitov@gmail.com; dmarc=pass (policy=none) header.from=gmail.com Received: by mail-wm1-f42.google.com with SMTP id 5b1f17b1804b1-43cfba466b2so13674675e9.3 for ; Thu, 20 Mar 2025 20:32:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1742527955; x=1743132755; darn=kvack.org; h=to:subject:message-id:date:from:mime-version:from:to:cc:subject :date:message-id:reply-to; bh=g9oozaQPCiW7aHMMJLEoWbHIJA+eqbljpGWao3hp29Y=; b=DjRrTr5WrK3zJofQpApyBr7rqVf6SoKODsW1hdwSa6nFP6neSr5dug+cUzCmolRD6Z YE4CEIr4Skf/GZaY4CIkYgUX6UxAeEgMJICbOiH9Ds7+4BSyDDs9Pmv1CvxJ/zmYruaC hDMM02S0QqIClbLXmtDWwW138FBj9cn9rlCARqXAwJPIdqUlgHGIMDWclSUiRtnBx/nr XjNOMmm36q5vpw5TM6QzbinzqqQKjvVd1T59bTK/e+UBh/TzbuM2CRua1df32s/+xPsE J43oNCjyoRBBAlzQMaoQlCoO5yis51/nB+PANDfuDFa+d9ZOUOGNl8TJiCcCDx4K7T13 CvMg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1742527955; x=1743132755; h=to:subject:message-id:date:from:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=g9oozaQPCiW7aHMMJLEoWbHIJA+eqbljpGWao3hp29Y=; b=iZt3RlLmJhMvKGO2qAXxyCNNBjVCidKymsQnnFWglNmgmJavc1R62dWhGLEUXxtxLH GK8wh0wo3Wj+uTFT/Q/8LFpneNluuIpJ1XPpNZfXF4cDNFcaPRkBIp118xvmSOtgee+Q e9xEfIW+YcDQWdRIQB2qy+tUedOMVK2ucm4hCQmrZU1Kdbt9ZhMeciOnj1xcYc5HcqhR NUx/M4dEv55zbXGMjmuUGDZ9Z9kXosnP/bnpcOKJhH3kl+dn44cHf/YT+4wfk0GaoFMq VF1HRU/T3tyC07rxH8U+zRGxQ5JIo0zA4KDjXOLWXdFLipj47ZoqhPPxfq+o8/UoFvXq ETDA== X-Forwarded-Encrypted: i=1; AJvYcCVBd/fTLKlWcypsf37YpXiGc0OS2q5TGcXf05oiV6hi+bKCRtOHHR8BfhsEroZsiRc7SUpa2xoi3Q==@kvack.org X-Gm-Message-State: AOJu0YxIeMek4RaNWhoeAZCk8183FcSeCiVzq9nWvePNJjmA48z+4jge d82eQ36cMOSNYouBe1AwktMf6KTF8OhmbkuHdJkro75jy0+WgxNyryv4H8y7rG3aKkm8/4pyTzj gkuC+5RHq2kOKjadWrFbmRxv6Go0= X-Gm-Gg: ASbGncvuSdIQfe+K45NbAt079dAcCtmHquVyNk+uqoV7yP49Dmf3d1ocNS9G9dWO1Sx U/vcGRMBH2PHtbebTBHVvVs3/oAUfbYEimMNI8XXlCxfBNBxtd4SMSK3uzFjNmUOXfEylnSlwg3 yiAePtk4Cw5COJHE08apkOatbr3fSEZr3TVQmxeknJgg== X-Google-Smtp-Source: AGHT+IGIKbPhkp/L3eskCCw8rn0DFYqCAzJh424BZ/d9vhS5L2/3pLgKQiiukxPyovMMfppzBlEF2bzphuyaw80maog= X-Received: by 2002:a05:600c:4f85:b0:43c:e481:3353 with SMTP id 5b1f17b1804b1-43d50a13947mr11235585e9.17.1742527955115; Thu, 20 Mar 2025 20:32:35 -0700 (PDT) MIME-Version: 1.0 From: Alexei Starovoitov Date: Thu, 20 Mar 2025 20:32:24 -0700 X-Gm-Features: AQ5f1JrYzK936gHVp14lqoGkzrbLD1DOiw4Ntzzohvehiz5wXVkOTU6kc56U5Tg Message-ID: Subject: [LSF/MM/BPF TOPIC] Reentrant kmalloc usable from any context To: lsf-pc , linux-mm , bpf , Vlastimil Babka , Sebastian Sewior , Michal Hocko , Andrew Morton , Dan Williams , Hou Tao , Steven Rostedt , Masami Hiramatsu Content-Type: text/plain; charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 150A78000B X-Stat-Signature: fg6rwkaxrdc3b4e3cmogifb89tdwcyt5 X-HE-Tag: 1742527956-40670 X-HE-Meta: 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 AD+XRMQi ZbPv6lQo2OK56n4hWJRBjY0J85h8PFLfxCi8w6pE9kfCQPtcwPl1rK9MtURMn6fLxneeJeyaweif6E5qF4Kbj9xIhHNUmSHiVyxvh2+DE98zLHxqqS3C1mliQiV60ClnETgyLpp9AJxQNcmkKXdEr8uk02hYXs6XlGdt+H0XJvxDq2Ipp7Zk6U1zqLaruFDRm8AmM0EI1b0azLkeFfiDhL41oxu5Ly9SQoh743x4SYxczZJbRJu8ET6UQi784+dXu35507UXJGpxR3C3sEtNB2w9iKoK6grmtd3/DegQAaZqStrcMyHJkrldFg4ZQIyOArChV6anBbO0xK7ZxFVjBeUUcU9f2uCa/mnKwlGBBKtZb+cEdKcZ8gVtvI0JBWXEcvzX2If4TD7ktgGbzjEpMLSdMQONY8bnbY63j X-Bogosity: Ham, tests=bogofilter, spamicity=0.061424, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: A year ago Vlastimil kicked off a discussion: "What's next for the SLUB allocator" https://lwn.net/Articles/974138/ One of the proposed goals was to adopt slub allocator to use cases where bespoke allocators are currently used either due to performance requirements or context restrictions. bpf_mem_alloc, kretprobe's objpool, mempool were mentioned as initial targets. netpoll should probably be on that list too. Performance might be addressed by sheaves while context restrictions are more difficult to solve. bpf, kretprobe, netpool don't know the context where they might be called. Currently bpf, kretprobe handler preallocate. Preallocated pools pin memory to one subsystem make it unavailable to the rest of the kernel. This has to be fixed. mm subsystem needs to own, share, distribute the memory. Agenda for the discussion: - discuss and agree on problem statement what is being solved, why, requirements of the solution - discuss pros and cons of the existing design that we made a bunch of progress on - brainstorm next steps