From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp1040.oracle.com ([141.146.126.69]:40265 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752053AbcFWNBL (ORCPT ); Thu, 23 Jun 2016 09:01:11 -0400 From: Anand Jain To: linux-btrfs@vger.kernel.org Cc: clm@fb.com, dsterba@suse.cz Subject: [PATCH RFC] don't background blkdev_put() Date: Thu, 23 Jun 2016 21:01:53 +0800 Message-Id: <1466686913-7832-1-git-send-email-anand.jain@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: As of now we are calling blkdev_put() under call_rcu, actually which isn't necessary. Unless I am missing something. This is a try out patch to know the same. Ran successfully the fstests. This should be applied on top of recent other patches, [PATCH 1/2] btrfs: reorg btrfs_close_one_device() [PATCH v3 2/2] btrfs: make sure device is synced before return Signed-off-by: Anand Jain --- fs/btrfs/volumes.c | 28 +++++++++++++++++++++++----- 1 file changed, 23 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index e0ad29d6fe9a..63036702ea18 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -834,10 +834,6 @@ static void __free_device(struct work_struct *work) struct btrfs_device *device; device = container_of(work, struct btrfs_device, rcu_work); - - if (device->bdev) - blkdev_put(device->bdev, device->mode); - rcu_string_free(device->name); kfree(device); } @@ -874,6 +870,8 @@ static void btrfs_close_one_device(struct btrfs_device *device) sync_blockdev(device->bdev); invalidate_bdev(device->bdev); } + if (device->bdev) + blkdev_put(device->bdev, device->mode); new_device = btrfs_alloc_device(NULL, &device->devid, device->uuid); @@ -1931,6 +1929,13 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path, u64 devid) btrfs_sysfs_rm_device_link(root->fs_info->fs_devices, device); } + if (device->bdev && device->writeable) { + sync_blockdev(device->bdev); + invalidate_bdev(device->bdev); + } + if (device->bdev) + blkdev_put(device->bdev, device->mode); + call_rcu(&device->rcu, free_device); num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1; @@ -2024,6 +2029,13 @@ void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info, /* zero out the old super if it is writable */ btrfs_scratch_superblocks(srcdev->bdev, srcdev->name->str); } + + if (srcdev->bdev && srcdev->writeable) { + sync_blockdev(srcdev->bdev); + invalidate_bdev(srcdev->bdev); + } + if (srcdev->bdev) + blkdev_put(srcdev->bdev, srcdev->mode); call_rcu(&srcdev->rcu, free_device); /* @@ -2079,6 +2091,12 @@ void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, * the device_list_mutex lock. */ btrfs_scratch_superblocks(tgtdev->bdev, tgtdev->name->str); + if (tgtdev->bdev && tgtdev->writeable) { + sync_blockdev(tgtdev->bdev); + invalidate_bdev(tgtdev->bdev); + } + if (tgtdev->bdev) + blkdev_put(tgtdev->bdev, tgtdev->mode); call_rcu(&tgtdev->rcu, free_device); } -- 2.7.0