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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 727A3CE7A88 for ; Sun, 24 Sep 2023 14:21:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229837AbjIXOWA (ORCPT ); Sun, 24 Sep 2023 10:22:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48714 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229782AbjIXOV5 (ORCPT ); Sun, 24 Sep 2023 10:21:57 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B04CDFB for ; Sun, 24 Sep 2023 07:21:51 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A8121C433C8; Sun, 24 Sep 2023 14:21:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1695565311; bh=h+by+Bpd3urcZtbmENRkjjPEMFhQuHlQ8ScQxWIt5nI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=WF3iltcHUuE60EUwiSfre9imVRIRFagHHoPZed4IDgYUxXm2D7Qpcvn7MRQO8gt+r WERMdkArOlxZ57kreyvIRWi0YuL81ddvlzu2GkI9EbRhpIxuzUyLclf2c1W2OPyPGp s0A7jrx1jwYyky3uKID+vhocl4zQ/SaBuZBP/iQef/j2xfTlHSTB5HQwwgrBQ5NTOc p2CR3IZGSzj+KLwrP0/QwdTmP7E0EQDxQtSFsyQYmM++0ZKZBtbuszk/aNr0d55BRX C064niKvXbM3YykUXgfcOe9NbDs4g3MmH0tw14BmrVk++X8KIHVJNixNI6EH3ztRq3 fvoNP7odJtuQA== Date: Sun, 24 Sep 2023 23:21:45 +0900 From: Masami Hiramatsu (Google) To: "wuqiang.matt" Cc: linux-trace-kernel@vger.kernel.org, davem@davemloft.net, anil.s.keshavamurthy@intel.com, naveen.n.rao@linux.ibm.com, rostedt@goodmis.org, peterz@infradead.org, akpm@linux-foundation.org, sander@svanheule.net, ebiggers@google.com, dan.j.williams@intel.com, jpoimboe@kernel.org, linux-kernel@vger.kernel.org, lkp@intel.com, mattwu@163.com Subject: Re: [PATCH v9 1/5] lib: objpool added: ring-array based lockless MPMC Message-Id: <20230924232145.05efde741742e24f3f4fd032@kernel.org> In-Reply-To: <20230905015255.81545-2-wuqiang.matt@bytedance.com> References: <20230905015255.81545-1-wuqiang.matt@bytedance.com> <20230905015255.81545-2-wuqiang.matt@bytedance.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Tue, 5 Sep 2023 09:52:51 +0800 "wuqiang.matt" wrote: > +/* cleanup all percpu slots of the object pool */ > +static void objpool_fini_percpu_slots(struct objpool_head *head) > +{ > + int i; > + > + if (!head->cpu_slots) > + return; > + > + for (i = 0; i < head->nr_cpus; i++) { > + if (!head->cpu_slots[i]) > + continue; > + if (head->flags & OBJPOOL_FROM_VMALLOC) > + vfree(head->cpu_slots[i]); > + else > + kfree(head->cpu_slots[i]); You can use kvfree() for both kmalloc object and vmalloc object. > + } > + kfree(head->cpu_slots); > + head->cpu_slots = NULL; > + head->slot_sizes = NULL; > +} ... > +/* drop the allocated object, rather reclaim it to objpool */ > +int objpool_drop(void *obj, struct objpool_head *head) > +{ > + if (!obj || !head) > + return -EINVAL; > + > + if (refcount_dec_and_test(&head->ref)) { > + objpool_free(head); > + return 0; > + } > + > + return -EAGAIN; > +} > +EXPORT_SYMBOL_GPL(objpool_drop); To make this work correctly, you need to disable the objpool (no more pop the object from it) and ensure the objpool is disabled. Also, when disabling the objpool, its refcount must be set to the "active" number of objects. Thank you, -- Masami Hiramatsu (Google)