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 7903EC77B78 for ; Wed, 3 May 2023 07:36:01 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D3B236B0074; Wed, 3 May 2023 03:36:00 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CC5326B0078; Wed, 3 May 2023 03:36:00 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B8C8B900002; Wed, 3 May 2023 03:36:00 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by kanga.kvack.org (Postfix) with ESMTP id 961776B0074 for ; Wed, 3 May 2023 03:36:00 -0400 (EDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 481782006F; Wed, 3 May 2023 07:35:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1683099359; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=i3Hzbp6Fc0h0hj5rYtAeMr0Bup0FedFGgjm/ljEsba4=; b=A1RUCh5ESqnCmqQHykA4qtiRA0TnekVST89bVweUc4YoOPAxXPAgcnp/rVynH6+pRPkp+z 0FzTPxhVUa0WAN3v90MiKxX/mhoNEqn2v/EhT/wx95G56Ej/zpg/VQwdKLa255ScGTYoBo r9VjFKfCEoqB/4FmnoBqhK5sAhIi958= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 0FDBE1331F; Wed, 3 May 2023 07:35:59 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id M6TzAt8OUmR+UgAAMHmgww (envelope-from ); Wed, 03 May 2023 07:35:59 +0000 Date: Wed, 3 May 2023 09:35:58 +0200 From: Michal Hocko To: Suren Baghdasaryan Cc: akpm@linux-foundation.org, kent.overstreet@linux.dev, vbabka@suse.cz, hannes@cmpxchg.org, roman.gushchin@linux.dev, mgorman@suse.de, dave@stgolabs.net, willy@infradead.org, liam.howlett@oracle.com, corbet@lwn.net, void@manifault.com, peterz@infradead.org, juri.lelli@redhat.com, ldufour@linux.ibm.com, catalin.marinas@arm.com, will@kernel.org, arnd@arndb.de, tglx@linutronix.de, mingo@redhat.com, dave.hansen@linux.intel.com, x86@kernel.org, peterx@redhat.com, david@redhat.com, axboe@kernel.dk, mcgrof@kernel.org, masahiroy@kernel.org, nathan@kernel.org, dennis@kernel.org, tj@kernel.org, muchun.song@linux.dev, rppt@kernel.org, paulmck@kernel.org, pasha.tatashin@soleen.com, yosryahmed@google.com, yuzhao@google.com, dhowells@redhat.com, hughd@google.com, andreyknvl@gmail.com, keescook@chromium.org, ndesaulniers@google.com, gregkh@linuxfoundation.org, ebiggers@google.com, ytcoode@gmail.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, bristot@redhat.com, vschneid@redhat.com, cl@linux.com, penberg@kernel.org, iamjoonsoo.kim@lge.com, 42.hyeyoo@gmail.com, glider@google.com, elver@google.com, dvyukov@google.com, shakeelb@google.com, songmuchun@bytedance.com, jbaron@akamai.com, rientjes@google.com, minchan@google.com, kaleshsingh@google.com, kernel-team@android.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, linux-arch@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-modules@vger.kernel.org, kasan-dev@googlegroups.com, cgroups@vger.kernel.org Subject: Re: [PATCH 34/40] lib: code tagging context capture support Message-ID: References: <20230501165450.15352-1-surenb@google.com> <20230501165450.15352-35-surenb@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230501165450.15352-35-surenb@google.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon 01-05-23 09:54:44, Suren Baghdasaryan wrote: [...] > +static inline void add_ctx(struct codetag_ctx *ctx, > + struct codetag_with_ctx *ctc) > +{ > + kref_init(&ctx->refcount); > + spin_lock(&ctc->ctx_lock); > + ctx->flags = CTC_FLAG_CTX_PTR; > + ctx->ctc = ctc; > + list_add_tail(&ctx->node, &ctc->ctx_head); > + spin_unlock(&ctc->ctx_lock); AFAIU every single tracked allocation will get its own codetag_ctx. There is no aggregation per allocation site or anything else. This looks like a scalability and a memory overhead red flag to me. > +} > + > +static inline void rem_ctx(struct codetag_ctx *ctx, > + void (*free_ctx)(struct kref *refcount)) > +{ > + struct codetag_with_ctx *ctc = ctx->ctc; > + > + spin_lock(&ctc->ctx_lock); This could deadlock when allocator is called from the IRQ context. > + /* ctx might have been removed while we were using it */ > + if (!list_empty(&ctx->node)) > + list_del_init(&ctx->node); > + spin_unlock(&ctc->ctx_lock); > + kref_put(&ctx->refcount, free_ctx); -- Michal Hocko SUSE Labs