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 X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 49AC6C4332F for ; Wed, 8 Sep 2021 02:54:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 357FF6112F for ; Wed, 8 Sep 2021 02:54:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347409AbhIHCzG (ORCPT ); Tue, 7 Sep 2021 22:55:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:50786 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347390AbhIHCyz (ORCPT ); Tue, 7 Sep 2021 22:54:55 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 639FB61102; Wed, 8 Sep 2021 02:53:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1631069618; bh=O6StOmZ2j0R8hLNekw4chhoiXAevn21by/zcPhccZxk=; h=Date:From:To:Subject:In-Reply-To:From; b=Cu/LE+Gsavpmb3z1nBO+PxgJc4Magg4l3L8PR/doSL+iOgCpd2SVC/OZO/ippEQnS ndusleHwhZmWYFljuHggMn1EKRNO2EGTMTvj3iRbd6W9JywS1cy/8XD5k7yUTvZXmY l8BgEBzm+HVi9sSYnm7mkrOtpy/0kw1MKSmRvR8k= Date: Tue, 07 Sep 2021 19:53:38 -0700 From: Andrew Morton To: akpm@linux-foundation.org, bigeasy@linutronix.de, brouer@redhat.com, cl@linux.com, efault@gmx.de, iamjoonsoo.kim@lge.com, jannh@google.com, linux-mm@kvack.org, mgorman@techsingularity.net, mm-commits@vger.kernel.org, penberg@kernel.org, quic_qiancai@quicinc.com, rientjes@google.com, tglx@linutronix.de, torvalds@linux-foundation.org, vbabka@suse.cz Subject: [patch 013/147] mm, slub: move disabling irqs closer to get_partial() in ___slab_alloc() Message-ID: <20210908025338.cwMi2m_6C%akpm@linux-foundation.org> In-Reply-To: <20210907195226.14b1d22a07c085b22968b933@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Vlastimil Babka Subject: mm, slub: move disabling irqs closer to get_partial() in ___slab_alloc() Continue reducing the irq disabled scope. Check for per-cpu partial slabs with first with irqs enabled and then recheck with irqs disabled before grabbing the slab page. Mostly preparatory for the following patches. Link: https://lkml.kernel.org/r/20210904105003.11688-14-vbabka@suse.cz Signed-off-by: Vlastimil Babka Cc: Christoph Lameter Cc: David Rientjes Cc: Jann Horn Cc: Jesper Dangaard Brouer Cc: Joonsoo Kim Cc: Mel Gorman Cc: Mike Galbraith Cc: Pekka Enberg Cc: Qian Cai Cc: Sebastian Andrzej Siewior Cc: Thomas Gleixner Signed-off-by: Andrew Morton --- mm/slub.c | 34 +++++++++++++++++++++++++--------- 1 file changed, 25 insertions(+), 9 deletions(-) --- a/mm/slub.c~mm-slub-move-disabling-irqs-closer-to-get_partial-in-___slab_alloc +++ a/mm/slub.c @@ -2706,11 +2706,6 @@ reread_page: if (unlikely(node != NUMA_NO_NODE && !node_isset(node, slab_nodes))) node = NUMA_NO_NODE; - local_irq_save(flags); - if (unlikely(c->page)) { - local_irq_restore(flags); - goto reread_page; - } goto new_slab; } redo: @@ -2751,6 +2746,7 @@ redo: if (!freelist) { c->page = NULL; + local_irq_restore(flags); stat(s, DEACTIVATE_BYPASS); goto new_slab; } @@ -2780,12 +2776,19 @@ deactivate_slab: goto reread_page; } deactivate_slab(s, page, c->freelist, c); + local_irq_restore(flags); new_slab: - lockdep_assert_irqs_disabled(); - if (slub_percpu_partial(c)) { + local_irq_save(flags); + if (unlikely(c->page)) { + local_irq_restore(flags); + goto reread_page; + } + if (unlikely(!slub_percpu_partial(c))) + goto new_objects; /* stolen by an IRQ handler */ + page = c->page = slub_percpu_partial(c); slub_set_percpu_partial(c, page); local_irq_restore(flags); @@ -2793,6 +2796,16 @@ new_slab: goto redo; } + local_irq_save(flags); + if (unlikely(c->page)) { + local_irq_restore(flags); + goto reread_page; + } + +new_objects: + + lockdep_assert_irqs_disabled(); + freelist = get_partial(s, gfpflags, node, &page); if (freelist) { c->page = page; @@ -2825,15 +2838,18 @@ new_slab: check_new_page: if (kmem_cache_debug(s)) { - if (!alloc_debug_processing(s, page, freelist, addr)) + if (!alloc_debug_processing(s, page, freelist, addr)) { /* Slab failed checks. Next slab needed */ + c->page = NULL; + local_irq_restore(flags); goto new_slab; - else + } else { /* * For debug case, we don't load freelist so that all * allocations go through alloc_debug_processing() */ goto return_single; + } } if (unlikely(!pfmemalloc_match(page, gfpflags))) _