From: "Darrick J. Wong" Subject: Re: [PATCH v2 1/2] fs, xfs: perform dax_device lookup at mount Date: Mon, 28 Aug 2017 09:28:27 -0700 Message-ID: <20170828162827.GA4757@magnolia> References: <150389211501.25151.6477753201827914462.stgit@dwillia2-desk3.amr.corp.intel.com> <150389212075.25151.17146973298430877023.stgit@dwillia2-desk3.amr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel@vger.kernel.org, jack@suse.cz, linux-nvdimm@lists.01.org, linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, hch@lst.de To: Dan Williams Return-path: Received: from aserp1040.oracle.com ([141.146.126.69]:34324 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751192AbdH1Q2l (ORCPT ); Mon, 28 Aug 2017 12:28:41 -0400 Content-Disposition: inline In-Reply-To: <150389212075.25151.17146973298430877023.stgit@dwillia2-desk3.amr.corp.intel.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Sun, Aug 27, 2017 at 08:48:40PM -0700, Dan Williams wrote: > The ->iomap_begin() operation is a hot path, so cache the > fs_dax_get_by_host() result at mount time to avoid the incurring the > hash lookup overhead on a per-i/o basis. > > Cc: "Darrick J. Wong" > Reported-by: Christoph Hellwig > Signed-off-by: Dan Williams Looks good, Reviewed-by: Darrick J. Wong > --- > drivers/dax/super.c | 10 ++++++++++ > fs/super.c | 26 +++++++++++++++++++++++--- > fs/xfs/xfs_aops.c | 13 +++++++++++++ > fs/xfs/xfs_aops.h | 1 + > fs/xfs/xfs_buf.c | 4 +++- > fs/xfs/xfs_buf.h | 3 ++- > fs/xfs/xfs_iomap.c | 10 +--------- > fs/xfs/xfs_super.c | 21 +++++++++++++++++---- > include/linux/dax.h | 6 ++++++ > include/linux/fs.h | 1 + > 10 files changed, 77 insertions(+), 18 deletions(-) > > diff --git a/drivers/dax/super.c b/drivers/dax/super.c > index 938eb4868f7f..b699aac268a6 100644 > --- a/drivers/dax/super.c > +++ b/drivers/dax/super.c > @@ -46,6 +46,8 @@ void dax_read_unlock(int id) > EXPORT_SYMBOL_GPL(dax_read_unlock); > > #ifdef CONFIG_BLOCK > +#include > + > int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size, > pgoff_t *pgoff) > { > @@ -59,6 +61,14 @@ int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size, > } > EXPORT_SYMBOL(bdev_dax_pgoff); > > +struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev) > +{ > + if (!blk_queue_dax(bdev->bd_queue)) > + return NULL; > + return fs_dax_get_by_host(bdev->bd_disk->disk_name); > +} > +EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev); > + > /** > * __bdev_dax_supported() - Check if the device supports dax for filesystem > * @sb: The superblock of the device > diff --git a/fs/super.c b/fs/super.c > index 6bc3352adcf3..671889b02bed 100644 > --- a/fs/super.c > +++ b/fs/super.c > @@ -23,6 +23,7 @@ > #include > #include > #include > +#include > #include > #include > #include /* for the emergency remount stuff */ > @@ -1048,9 +1049,17 @@ struct dentry *mount_ns(struct file_system_type *fs_type, > EXPORT_SYMBOL(mount_ns); > > #ifdef CONFIG_BLOCK > +struct sget_devs { > + struct block_device *bdev; > + struct dax_device *dax_dev; > +}; > + > static int set_bdev_super(struct super_block *s, void *data) > { > - s->s_bdev = data; > + struct sget_devs *devs = data; > + > + s->s_bdev = devs->bdev; > + s->s_daxdev = devs->dax_dev; > s->s_dev = s->s_bdev->bd_dev; > s->s_bdi = bdi_get(s->s_bdev->bd_bdi); > > @@ -1059,14 +1068,18 @@ static int set_bdev_super(struct super_block *s, void *data) > > static int test_bdev_super(struct super_block *s, void *data) > { > - return (void *)s->s_bdev == data; > + struct sget_devs *devs = data; > + > + return s->s_bdev == devs->bdev; > } > > struct dentry *mount_bdev(struct file_system_type *fs_type, > int flags, const char *dev_name, void *data, > int (*fill_super)(struct super_block *, void *, int)) > { > + struct sget_devs devs; > struct block_device *bdev; > + struct dax_device *dax_dev; > struct super_block *s; > fmode_t mode = FMODE_READ | FMODE_EXCL; > int error = 0; > @@ -1077,6 +1090,7 @@ struct dentry *mount_bdev(struct file_system_type *fs_type, > bdev = blkdev_get_by_path(dev_name, mode, fs_type); > if (IS_ERR(bdev)) > return ERR_CAST(bdev); > + dax_dev = fs_dax_get_by_bdev(bdev); > > /* > * once the super is inserted into the list by sget, s_umount > @@ -1089,8 +1103,10 @@ struct dentry *mount_bdev(struct file_system_type *fs_type, > error = -EBUSY; > goto error_bdev; > } > + devs.bdev = bdev; > + devs.dax_dev = dax_dev; > s = sget(fs_type, test_bdev_super, set_bdev_super, flags | MS_NOSEC, > - bdev); > + &devs); > mutex_unlock(&bdev->bd_fsfreeze_mutex); > if (IS_ERR(s)) > goto error_s; > @@ -1111,6 +1127,7 @@ struct dentry *mount_bdev(struct file_system_type *fs_type, > */ > up_write(&s->s_umount); > blkdev_put(bdev, mode); > + fs_put_dax(dax_dev); > down_write(&s->s_umount); > } else { > s->s_mode = mode; > @@ -1132,6 +1149,7 @@ struct dentry *mount_bdev(struct file_system_type *fs_type, > error = PTR_ERR(s); > error_bdev: > blkdev_put(bdev, mode); > + fs_put_dax(dax_dev); > error: > return ERR_PTR(error); > } > @@ -1140,6 +1158,7 @@ EXPORT_SYMBOL(mount_bdev); > void kill_block_super(struct super_block *sb) > { > struct block_device *bdev = sb->s_bdev; > + struct dax_device *dax_dev = sb->s_daxdev; > fmode_t mode = sb->s_mode; > > bdev->bd_super = NULL; > @@ -1147,6 +1166,7 @@ void kill_block_super(struct super_block *sb) > sync_blockdev(bdev); > WARN_ON_ONCE(!(mode & FMODE_EXCL)); > blkdev_put(bdev, mode | FMODE_EXCL); > + fs_put_dax(dax_dev); > } > > EXPORT_SYMBOL(kill_block_super); > diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c > index 6bf120bb1a17..78185f3b10b2 100644 > --- a/fs/xfs/xfs_aops.c > +++ b/fs/xfs/xfs_aops.c > @@ -80,6 +80,19 @@ xfs_find_bdev_for_inode( > return mp->m_ddev_targp->bt_bdev; > } > > +struct dax_device * > +xfs_find_daxdev_for_inode( > + struct inode *inode) > +{ > + struct xfs_inode *ip = XFS_I(inode); > + struct xfs_mount *mp = ip->i_mount; > + > + if (XFS_IS_REALTIME_INODE(ip)) > + return mp->m_rtdev_targp->bt_daxdev; > + else > + return mp->m_ddev_targp->bt_daxdev; > +} > + > /* > * We're now finished for good with this page. Update the page state via the > * associated buffer_heads, paying attention to the start and end offsets that > diff --git a/fs/xfs/xfs_aops.h b/fs/xfs/xfs_aops.h > index cc174ec6c2fd..88c85ea63da0 100644 > --- a/fs/xfs/xfs_aops.h > +++ b/fs/xfs/xfs_aops.h > @@ -59,5 +59,6 @@ int xfs_setfilesize(struct xfs_inode *ip, xfs_off_t offset, size_t size); > > extern void xfs_count_page_state(struct page *, int *, int *); > extern struct block_device *xfs_find_bdev_for_inode(struct inode *); > +extern struct dax_device *xfs_find_daxdev_for_inode(struct inode *); > > #endif /* __XFS_AOPS_H__ */ > diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c > index 72f038492ba8..6deb86c845d1 100644 > --- a/fs/xfs/xfs_buf.c > +++ b/fs/xfs/xfs_buf.c > @@ -1802,7 +1802,8 @@ xfs_setsize_buftarg_early( > xfs_buftarg_t * > xfs_alloc_buftarg( > struct xfs_mount *mp, > - struct block_device *bdev) > + struct block_device *bdev, > + struct dax_device *dax_dev) > { > xfs_buftarg_t *btp; > > @@ -1811,6 +1812,7 @@ xfs_alloc_buftarg( > btp->bt_mount = mp; > btp->bt_dev = bdev->bd_dev; > btp->bt_bdev = bdev; > + btp->bt_daxdev = dax_dev; > > if (xfs_setsize_buftarg_early(btp, bdev)) > goto error; > diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h > index 20721261dae5..bf71507ddb16 100644 > --- a/fs/xfs/xfs_buf.h > +++ b/fs/xfs/xfs_buf.h > @@ -108,6 +108,7 @@ typedef unsigned int xfs_buf_flags_t; > typedef struct xfs_buftarg { > dev_t bt_dev; > struct block_device *bt_bdev; > + struct dax_device *bt_daxdev; > struct xfs_mount *bt_mount; > unsigned int bt_meta_sectorsize; > size_t bt_meta_sectormask; > @@ -385,7 +386,7 @@ xfs_buf_update_cksum(struct xfs_buf *bp, unsigned long cksum_offset) > * Handling of buftargs. > */ > extern xfs_buftarg_t *xfs_alloc_buftarg(struct xfs_mount *, > - struct block_device *); > + struct block_device *, struct dax_device *); > extern void xfs_free_buftarg(struct xfs_mount *, struct xfs_buftarg *); > extern void xfs_wait_buftarg(xfs_buftarg_t *); > extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int); > diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c > index 813394c62849..7c934e407332 100644 > --- a/fs/xfs/xfs_iomap.c > +++ b/fs/xfs/xfs_iomap.c > @@ -69,6 +69,7 @@ xfs_bmbt_to_iomap( > iomap->offset = XFS_FSB_TO_B(mp, imap->br_startoff); > iomap->length = XFS_FSB_TO_B(mp, imap->br_blockcount); > iomap->bdev = xfs_find_bdev_for_inode(VFS_I(ip)); > + iomap->dax_dev = xfs_find_daxdev_for_inode(VFS_I(ip)); > } > > xfs_extlen_t > @@ -976,7 +977,6 @@ xfs_file_iomap_begin( > int nimaps = 1, error = 0; > bool shared = false, trimmed = false; > unsigned lockmode; > - struct block_device *bdev; > > if (XFS_FORCED_SHUTDOWN(mp)) > return -EIO; > @@ -1087,13 +1087,6 @@ xfs_file_iomap_begin( > > xfs_bmbt_to_iomap(ip, iomap, &imap); > > - /* optionally associate a dax device with the iomap bdev */ > - bdev = iomap->bdev; > - if (blk_queue_dax(bdev->bd_queue)) > - iomap->dax_dev = fs_dax_get_by_host(bdev->bd_disk->disk_name); > - else > - iomap->dax_dev = NULL; > - > if (shared) > iomap->flags |= IOMAP_F_SHARED; > return 0; > @@ -1171,7 +1164,6 @@ xfs_file_iomap_end( > unsigned flags, > struct iomap *iomap) > { > - fs_put_dax(iomap->dax_dev); > if ((flags & IOMAP_WRITE) && iomap->type == IOMAP_DELALLOC) > return xfs_file_iomap_end_delalloc(XFS_I(inode), offset, > length, written, iomap); > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c > index 38aaacdbb8b3..d863f96b16e2 100644 > --- a/fs/xfs/xfs_super.c > +++ b/fs/xfs/xfs_super.c > @@ -716,13 +716,19 @@ xfs_close_devices( > { > if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) { > struct block_device *logdev = mp->m_logdev_targp->bt_bdev; > + struct dax_device *dax_logdev = mp->m_logdev_targp->bt_daxdev; > + > xfs_free_buftarg(mp, mp->m_logdev_targp); > xfs_blkdev_put(logdev); > + fs_put_dax(dax_logdev); > } > if (mp->m_rtdev_targp) { > struct block_device *rtdev = mp->m_rtdev_targp->bt_bdev; > + struct dax_device *dax_rtdev = mp->m_rtdev_targp->bt_daxdev; > + > xfs_free_buftarg(mp, mp->m_rtdev_targp); > xfs_blkdev_put(rtdev); > + fs_put_dax(dax_rtdev); > } > xfs_free_buftarg(mp, mp->m_ddev_targp); > } > @@ -742,7 +748,9 @@ xfs_open_devices( > struct xfs_mount *mp) > { > struct block_device *ddev = mp->m_super->s_bdev; > + struct dax_device *dax_ddev = mp->m_super->s_daxdev; > struct block_device *logdev = NULL, *rtdev = NULL; > + struct dax_device *dax_logdev = NULL, *dax_rtdev = NULL; > int error; > > /* > @@ -752,6 +760,7 @@ xfs_open_devices( > error = xfs_blkdev_get(mp, mp->m_logname, &logdev); > if (error) > goto out; > + dax_logdev = fs_dax_get_by_bdev(logdev); > } > > if (mp->m_rtname) { > @@ -765,24 +774,25 @@ xfs_open_devices( > error = -EINVAL; > goto out_close_rtdev; > } > + dax_rtdev = fs_dax_get_by_bdev(rtdev); > } > > /* > * Setup xfs_mount buffer target pointers > */ > error = -ENOMEM; > - mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev); > + mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev, dax_ddev); > if (!mp->m_ddev_targp) > goto out_close_rtdev; > > if (rtdev) { > - mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev); > + mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev, dax_rtdev); > if (!mp->m_rtdev_targp) > goto out_free_ddev_targ; > } > > if (logdev && logdev != ddev) { > - mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev); > + mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev, dax_logdev); > if (!mp->m_logdev_targp) > goto out_free_rtdev_targ; > } else { > @@ -798,9 +808,12 @@ xfs_open_devices( > xfs_free_buftarg(mp, mp->m_ddev_targp); > out_close_rtdev: > xfs_blkdev_put(rtdev); > + fs_put_dax(dax_rtdev); > out_close_logdev: > - if (logdev && logdev != ddev) > + if (logdev && logdev != ddev) { > xfs_blkdev_put(logdev); > + fs_put_dax(dax_logdev); > + } > out: > return error; > } > diff --git a/include/linux/dax.h b/include/linux/dax.h > index df97b7af7e2c..6e32be3badec 100644 > --- a/include/linux/dax.h > +++ b/include/linux/dax.h > @@ -57,6 +57,7 @@ static inline void fs_put_dax(struct dax_device *dax_dev) > put_dax(dax_dev); > } > > +struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev); > #else > static inline int bdev_dax_supported(struct super_block *sb, int blocksize) > { > @@ -71,6 +72,11 @@ static inline struct dax_device *fs_dax_get_by_host(const char *host) > static inline void fs_put_dax(struct dax_device *dax_dev) > { > } > + > +struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev) > +{ > + return NULL; > +} > #endif > > int dax_read_lock(void); > diff --git a/include/linux/fs.h b/include/linux/fs.h > index 6e1fd5d21248..d0e3234a1fae 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -1334,6 +1334,7 @@ struct super_block { > struct hlist_bl_head s_anon; /* anonymous dentries for (nfs) exporting */ > struct list_head s_mounts; /* list of mounts; _not_ for fs use */ > struct block_device *s_bdev; > + struct dax_device *s_daxdev; > struct backing_dev_info *s_bdi; > struct mtd_info *s_mtd; > struct hlist_node s_instances; > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html