From nobody Thu Sep 11 22:30:54 2025 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 0CFA1EB64DD for ; Mon, 7 Aug 2023 11:19:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232363AbjHGLTA (ORCPT ); Mon, 7 Aug 2023 07:19:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52822 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232762AbjHGLSp (ORCPT ); Mon, 7 Aug 2023 07:18:45 -0400 Received: from mail-pj1-x102b.google.com (mail-pj1-x102b.google.com [IPv6:2607:f8b0:4864:20::102b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4CB2F19A2 for ; Mon, 7 Aug 2023 04:17:27 -0700 (PDT) Received: by mail-pj1-x102b.google.com with SMTP id 98e67ed59e1d1-268f6ba57b5so625130a91.1 for ; Mon, 07 Aug 2023 04:17:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1691406994; x=1692011794; 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=VutXoqIYPXtXpdtpLBT8bT2urW1s48myud5I+McDwEBCa9rsQtPimBr+YUFUzsT97Y MjfZoj9VTU5fQdJYfMy4Yv9+fpoIS3NFbuatZ84CQCYl8H9eWSOHmEJiwCeaGu2opion jdT+b5LnvY412zroG7MGUq7fLqOt080kwGO2vU4AXzRlkef5xzEfjXjzk3KbTMiuBQm9 X5miROMvoH95e1ANj7PpglZT3M6nqFHwr/l7jXhn2TxbPNm1IYfgnlH3CAsHhpdGLp2V N9EQiXy6+755vxTQtpjB+rXzevwen4FSNuxTXEorqPqLUTQJulIk6PKsXEt+umpl0/zu QYGw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691406994; x=1692011794; 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=N28y/iyICrAa+PK6llMnFfiHh5Fogc92SioCo5jR1g7tQDj+6xI/OjvkFD0vPZ+SOS +20L7OL6EgJt7URe06GFE0x9finZ6ftC+Z+8IzNJcUbcIKVPaHd9K1QZ4uM5RGbVs4LJ yEAJi4XLURCP6RJ2qltx2Z4lcuegqCyd+D94+7wF4IKzy+MgTqcP5COpViELUc9Fyfua 3x4Vk8awfvvHBhpWEded7gRGfZq9/KSJAgl7xksJVefwPdSyuHysETJlU4y+10qKzqwv wnrIlgtKmWSH0EqCTV4NsJkNlARxrDGFgaQXvswo6cuLJUZ1O8R2ANNWaqQ569JibeWr zuPQ== X-Gm-Message-State: AOJu0Yyqe+ElH0LHhvUIrlw/cCzfhgIEYDyfmvRkfdo6NJiQ85b33/lZ WqkwRsMit54TgOtgxVAir+pQew== X-Google-Smtp-Source: AGHT+IF623rMYCfdnVm3rDQUM9QMv5wRA4teIiBc32f8XUPEVkH5VguN8eCSFu0xAaU5upe3gsVL9w== X-Received: by 2002:a17:90a:6701:b0:269:32c7:24dc with SMTP id n1-20020a17090a670100b0026932c724dcmr6035493pjj.0.1691406994765; Mon, 07 Aug 2023 04:16:34 -0700 (PDT) Received: from C02DW0BEMD6R.bytedance.net ([203.208.167.146]) by smtp.gmail.com with ESMTPSA id y13-20020a17090aca8d00b0025be7b69d73sm5861191pjt.12.2023.08.07.04.16.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Aug 2023 04:16:34 -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, simon.horman@corigine.com, dlemoal@kernel.org 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 v4 31/48] virtio_balloon: dynamically allocate the virtio-balloon shrinker Date: Mon, 7 Aug 2023 19:09:19 +0800 Message-Id: <20230807110936.21819-32-zhengqi.arch@bytedance.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20230807110936.21819-1-zhengqi.arch@bytedance.com> References: <20230807110936.21819-1-zhengqi.arch@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 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_balloo= n.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]; =20 /* Shrinker to return free pages - VIRTIO_BALLOON_F_FREE_PAGE_HINT */ - struct shrinker shrinker; + struct shrinker *shrinker; =20 /* 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_ba= lloon *vb, static unsigned long virtio_balloon_shrinker_scan(struct shrinker *shrinke= r, struct shrink_control *sc) { - struct virtio_balloon *vb =3D container_of(shrinker, - struct virtio_balloon, shrinker); + struct virtio_balloon *vb =3D shrinker->private_data; =20 return shrink_free_pages(vb, sc->nr_to_scan); } @@ -825,8 +824,7 @@ static unsigned long virtio_balloon_shrinker_scan(struc= t shrinker *shrinker, static unsigned long virtio_balloon_shrinker_count(struct shrinker *shrink= er, struct shrink_control *sc) { - struct virtio_balloon *vb =3D container_of(shrinker, - struct virtio_balloon, shrinker); + struct virtio_balloon *vb =3D shrinker->private_data; =20 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, =20 static void virtio_balloon_unregister_shrinker(struct virtio_balloon *vb) { - unregister_shrinker(&vb->shrinker); + shrinker_free(vb->shrinker); } =20 static int virtio_balloon_register_shrinker(struct virtio_balloon *vb) { - vb->shrinker.scan_objects =3D virtio_balloon_shrinker_scan; - vb->shrinker.count_objects =3D virtio_balloon_shrinker_count; - vb->shrinker.seeks =3D DEFAULT_SEEKS; + vb->shrinker =3D shrinker_alloc(0, "virtio-balloon"); + if (!vb->shrinker) + return -ENOMEM; =20 - return register_shrinker(&vb->shrinker, "virtio-balloon"); + vb->shrinker->scan_objects =3D virtio_balloon_shrinker_scan; + vb->shrinker->count_objects =3D virtio_balloon_shrinker_count; + vb->shrinker->seeks =3D DEFAULT_SEEKS; + vb->shrinker->private_data =3D vb; + + shrinker_register(vb->shrinker); + + return 0; } =20 static int virtballoon_probe(struct virtio_device *vdev) --=20 2.30.2