From patchwork Thu Jul 27 08:04:45 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qi Zheng X-Patchwork-Id: 13329622 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 9150EC04FDF for ; Thu, 27 Jul 2023 08:24:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233390AbjG0IYg (ORCPT ); Thu, 27 Jul 2023 04:24:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55254 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232746AbjG0IWH (ORCPT ); Thu, 27 Jul 2023 04:22:07 -0400 Received: from mail-pf1-x42c.google.com (mail-pf1-x42c.google.com [IPv6:2607:f8b0:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BEF353AAD for ; Thu, 27 Jul 2023 01:13:22 -0700 (PDT) Received: by mail-pf1-x42c.google.com with SMTP id d2e1a72fcca58-682eef7d752so204676b3a.0 for ; Thu, 27 Jul 2023 01:13:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1690445538; x=1691050338; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=nhs5C6wYTK112tB0Y3rKeCsMBEmGx3fQoCnqZ3HCCLA=; b=P3BNYmrnn+aNeQX6tJNAWjBR47qoFVwe6V1hXSSWwFyS61HuOjfx1CldC/bVPLDS4b tBSPVcIpokpC1gG54dPeypV2gv1H1PsrEki/AFkEglXm+WyAmzSAHFAjlypTbwzHUkTv XwwWUlwnKhA8sSKQw+cOvBa/dT3CBu+sYvYNSpbwNT6pp20knmU+insJC0lJR8d7KNA/ XFw3RfaoZY9/IU0U207vkdiCmyduxENHuADRmTAqpUtqVvF1N7pwLKXyEsFC4IstCLHw nMtpKLIm0n/1aYuhmB1FsTVe4JczwGUa2wEUGkSK8KQu0Fafs8lJ3mpNN+7ETdaWOSMf 16qA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1690445538; x=1691050338; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=nhs5C6wYTK112tB0Y3rKeCsMBEmGx3fQoCnqZ3HCCLA=; b=kN1aODYNCVZpoaiNOt9HsShrFzSP9veKMmZNStW7CsoxSyOqtoqQqH7PmKgjHeQ9TQ q0v1t01pRRH7hYO9XbArY/KR6vSyACVOGJO1kfAVEfTfM7ImTz7yWUzOSseYQWGKpsWm WQseZf6lQZh37RbVrUbpC/rDJje4+4ULXRpxBRuh/fl3zkClwi0hdWsHTRVqi35gcQMU MaiwiDS2/yz2edkUdF/dR8gmsztZgRxGBJVyRM2qnXkvEjR0sYlg5yamV2UGnyeqive4 ifUXTlYPKFikqoLKyTmvsCszC4vphuUpw9O0olADy6yBxTOGNaa9w5FR6BFD1aHIR6Bm 48ew== X-Gm-Message-State: ABy/qLZq6txnnJWQB4jkp8dQb/TVeRHXXo/OYTBum4LtX3Y5TtbR3DxU 98YX7pGY9MipzITleGbm4SgYsg== X-Google-Smtp-Source: APBJJlELYJ+VP3jkb44itFX28rq7UhufR3zr/NDN3xCao+bv4nVfpqzapahZiZsalg40ZmAEO1GP5Q== X-Received: by 2002:a05:6a00:13a3:b0:676:2a5c:7bc5 with SMTP id t35-20020a056a0013a300b006762a5c7bc5mr5236670pfg.1.1690445537850; Thu, 27 Jul 2023 01:12:17 -0700 (PDT) Received: from C02DW0BEMD6R.bytedance.net ([203.208.167.147]) by smtp.gmail.com with ESMTPSA id j8-20020aa78d08000000b006828e49c04csm885872pfe.75.2023.07.27.01.12.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 27 Jul 2023 01:12:17 -0700 (PDT) From: Qi Zheng To: akpm@linux-foundation.org, david@fromorbit.com, tkhai@ya.ru, vbabka@suse.cz, roman.gushchin@linux.dev, djwong@kernel.org, brauner@kernel.org, paulmck@kernel.org, tytso@mit.edu, steven.price@arm.com, cel@kernel.org, senozhatsky@chromium.org, yujie.liu@intel.com, gregkh@linuxfoundation.org, muchun.song@linux.dev Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org, linux-erofs@lists.ozlabs.org, linux-f2fs-devel@lists.sourceforge.net, cluster-devel@redhat.com, linux-nfs@vger.kernel.org, linux-mtd@lists.infradead.org, rcu@vger.kernel.org, netdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, dm-devel@redhat.com, linux-raid@vger.kernel.org, linux-bcache@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, linux-btrfs@vger.kernel.org, Qi Zheng , Muchun Song Subject: [PATCH v3 32/49] virtio_balloon: dynamically allocate the virtio-balloon shrinker Date: Thu, 27 Jul 2023 16:04:45 +0800 Message-Id: <20230727080502.77895-33-zhengqi.arch@bytedance.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20230727080502.77895-1-zhengqi.arch@bytedance.com> References: <20230727080502.77895-1-zhengqi.arch@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org In preparation for implementing lockless slab shrink, use new APIs to dynamically allocate the virtio-balloon shrinker, so that it can be freed asynchronously using kfree_rcu(). Then it doesn't need to wait for RCU read-side critical section when releasing the struct virtio_balloon. Signed-off-by: Qi Zheng Reviewed-by: Muchun Song --- drivers/virtio/virtio_balloon.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 5b15936a5214..82e6087073a9 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -111,7 +111,7 @@ struct virtio_balloon { struct virtio_balloon_stat stats[VIRTIO_BALLOON_S_NR]; /* Shrinker to return free pages - VIRTIO_BALLOON_F_FREE_PAGE_HINT */ - struct shrinker shrinker; + struct shrinker *shrinker; /* OOM notifier to deflate on OOM - VIRTIO_BALLOON_F_DEFLATE_ON_OOM */ struct notifier_block oom_nb; @@ -816,8 +816,7 @@ static unsigned long shrink_free_pages(struct virtio_balloon *vb, static unsigned long virtio_balloon_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) { - struct virtio_balloon *vb = container_of(shrinker, - struct virtio_balloon, shrinker); + struct virtio_balloon *vb = shrinker->private_data; return shrink_free_pages(vb, sc->nr_to_scan); } @@ -825,8 +824,7 @@ static unsigned long virtio_balloon_shrinker_scan(struct shrinker *shrinker, static unsigned long virtio_balloon_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc) { - struct virtio_balloon *vb = container_of(shrinker, - struct virtio_balloon, shrinker); + struct virtio_balloon *vb = shrinker->private_data; return vb->num_free_page_blocks * VIRTIO_BALLOON_HINT_BLOCK_PAGES; } @@ -847,16 +845,23 @@ static int virtio_balloon_oom_notify(struct notifier_block *nb, static void virtio_balloon_unregister_shrinker(struct virtio_balloon *vb) { - unregister_shrinker(&vb->shrinker); + shrinker_free(vb->shrinker); } static int virtio_balloon_register_shrinker(struct virtio_balloon *vb) { - vb->shrinker.scan_objects = virtio_balloon_shrinker_scan; - vb->shrinker.count_objects = virtio_balloon_shrinker_count; - vb->shrinker.seeks = DEFAULT_SEEKS; + vb->shrinker = shrinker_alloc(0, "virtio-balloon"); + if (!vb->shrinker) + return -ENOMEM; - return register_shrinker(&vb->shrinker, "virtio-balloon"); + vb->shrinker->scan_objects = virtio_balloon_shrinker_scan; + vb->shrinker->count_objects = virtio_balloon_shrinker_count; + vb->shrinker->seeks = DEFAULT_SEEKS; + vb->shrinker->private_data = vb; + + shrinker_register(vb->shrinker); + + return 0; } static int virtballoon_probe(struct virtio_device *vdev)