From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp1040.oracle.com ([141.146.126.69]:31743 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754088AbdJaWfN (ORCPT ); Tue, 31 Oct 2017 18:35:13 -0400 Date: Tue, 31 Oct 2017 15:35:08 -0700 From: "Darrick J. Wong" Subject: Re: [PATCH 15/18] xfs: remove support for inlining data/extents into the inode fork Message-ID: <20171031223508.GY4911@magnolia> References: <20171031142230.11755-1-hch@lst.de> <20171031142230.11755-16-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171031142230.11755-16-hch@lst.de> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Christoph Hellwig Cc: linux-xfs@vger.kernel.org On Tue, Oct 31, 2017 at 04:22:27PM +0200, Christoph Hellwig wrote: > Supporting a small bit of data inside the inode fork blows up the fork size > a lot, removing the 32 bytes of inline data halves the effective size of > the inode fork (and it still has a lot of unused padding left), and the > performance of a single kmalloc doesn't show up compared to the size to read > an inode or create one. Do you see any secondary effects, such as increased slab fragmentation because of the extra kmem_allocs? In general I think this should be ok, I just worry slightly that whatever reason we had for having if_inline_data is still around and will blow up in weird ways if we get rid of it. (I will go play with scrub on a big filesystem to see if it runs noticeably slower or goes whacky.) Code-wise, Reviewed-by: Darrick J. Wong --D > > It also simplifies the fork management code a lot. > > Signed-off-by: Christoph Hellwig > --- > fs/xfs/libxfs/xfs_inode_fork.c | 185 +++-------------------------------------- > fs/xfs/libxfs/xfs_inode_fork.h | 11 --- > fs/xfs/xfs_bmap_util.c | 15 ---- > 3 files changed, 13 insertions(+), 198 deletions(-) > > diff --git a/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c > index c9e10d4818b7..5ac341d2b093 100644 > --- a/fs/xfs/libxfs/xfs_inode_fork.c > +++ b/fs/xfs/libxfs/xfs_inode_fork.c > @@ -269,19 +269,14 @@ xfs_init_local_fork( > if (zero_terminate) > mem_size++; > > - if (size == 0) > - ifp->if_u1.if_data = NULL; > - else if (mem_size <= sizeof(ifp->if_u2.if_inline_data)) > - ifp->if_u1.if_data = ifp->if_u2.if_inline_data; > - else { > + if (size) { > real_size = roundup(mem_size, 4); > ifp->if_u1.if_data = kmem_alloc(real_size, KM_SLEEP | KM_NOFS); > - } > - > - if (size) { > memcpy(ifp->if_u1.if_data, data, size); > if (zero_terminate) > ifp->if_u1.if_data[size] = '\0'; > + } else { > + ifp->if_u1.if_data = NULL; > } > > ifp->if_bytes = size; > @@ -292,13 +287,6 @@ xfs_init_local_fork( > > /* > * The file is in-lined in the on-disk inode. > - * If it fits into if_inline_data, then copy > - * it there, otherwise allocate a buffer for it > - * and copy the data there. Either way, set > - * if_data to point at the data. > - * If we allocate a buffer for the data, make > - * sure that its size is a multiple of 4 and > - * record the real size in i_real_bytes. > */ > STATIC int > xfs_iformat_local( > @@ -328,9 +316,7 @@ xfs_iformat_local( > > /* > * The file consists of a set of extents all of which fit into the on-disk > - * inode. If there are few enough extents to fit into the if_inline_ext, then > - * copy them there. Otherwise allocate a buffer for them and copy them into it. > - * Either way, set if_extents to point at the extents. > + * inode. > */ > STATIC int > xfs_iformat_extents( > @@ -362,8 +348,6 @@ xfs_iformat_extents( > ifp->if_real_bytes = 0; > if (nex == 0) > ifp->if_u1.if_extents = NULL; > - else if (nex <= XFS_INLINE_EXTS) > - ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext; > else > xfs_iext_add(ifp, 0, nex); > > @@ -618,26 +602,9 @@ xfs_idata_realloc( > ASSERT(new_size >= 0); > > if (new_size == 0) { > - if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) { > - kmem_free(ifp->if_u1.if_data); > - } > + kmem_free(ifp->if_u1.if_data); > ifp->if_u1.if_data = NULL; > real_size = 0; > - } else if (new_size <= sizeof(ifp->if_u2.if_inline_data)) { > - /* > - * If the valid extents/data can fit in if_inline_ext/data, > - * copy them from the malloc'd vector and free it. > - */ > - if (ifp->if_u1.if_data == NULL) { > - ifp->if_u1.if_data = ifp->if_u2.if_inline_data; > - } else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) { > - ASSERT(ifp->if_real_bytes != 0); > - memcpy(ifp->if_u2.if_inline_data, ifp->if_u1.if_data, > - new_size); > - kmem_free(ifp->if_u1.if_data); > - ifp->if_u1.if_data = ifp->if_u2.if_inline_data; > - } > - real_size = 0; > } else { > /* > * Stuck with malloc/realloc. > @@ -651,7 +618,7 @@ xfs_idata_realloc( > ASSERT(ifp->if_real_bytes == 0); > ifp->if_u1.if_data = kmem_alloc(real_size, > KM_SLEEP | KM_NOFS); > - } else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) { > + } else { > /* > * Only do the realloc if the underlying size > * is really changing. > @@ -662,12 +629,6 @@ xfs_idata_realloc( > real_size, > KM_SLEEP | KM_NOFS); > } > - } else { > - ASSERT(ifp->if_real_bytes == 0); > - ifp->if_u1.if_data = kmem_alloc(real_size, > - KM_SLEEP | KM_NOFS); > - memcpy(ifp->if_u1.if_data, ifp->if_u2.if_inline_data, > - ifp->if_bytes); > } > } > ifp->if_real_bytes = real_size; > @@ -695,8 +656,7 @@ xfs_idestroy_fork( > * so check and free it up if we do. > */ > if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) { > - if ((ifp->if_u1.if_data != ifp->if_u2.if_inline_data) && > - (ifp->if_u1.if_data != NULL)) { > + if (ifp->if_u1.if_data != NULL) { > ASSERT(ifp->if_real_bytes != 0); > kmem_free(ifp->if_u1.if_data); > ifp->if_u1.if_data = NULL; > @@ -704,13 +664,11 @@ xfs_idestroy_fork( > } > } else if ((ifp->if_flags & XFS_IFEXTENTS) && > ((ifp->if_flags & XFS_IFEXTIREC) || > - ((ifp->if_u1.if_extents != NULL) && > - (ifp->if_u1.if_extents != ifp->if_u2.if_inline_ext)))) { > + (ifp->if_u1.if_extents != NULL))) { > ASSERT(ifp->if_real_bytes != 0); > xfs_iext_destroy(ifp); > } > - ASSERT(ifp->if_u1.if_extents == NULL || > - ifp->if_u1.if_extents == ifp->if_u2.if_inline_ext); > + ASSERT(ifp->if_u1.if_extents == NULL); > ASSERT(ifp->if_real_bytes == 0); > if (whichfork == XFS_ATTR_FORK) { > kmem_zone_free(xfs_ifork_zone, ip->i_afp); > @@ -943,28 +901,14 @@ xfs_iext_add( > ASSERT((idx >= 0) && (idx <= nextents)); > byte_diff = ext_diff * sizeof(xfs_bmbt_rec_t); > new_size = ifp->if_bytes + byte_diff; > + > /* > - * If the new number of extents (nextents + ext_diff) > - * fits inside the inode, then continue to use the inline > - * extent buffer. > - */ > - if (nextents + ext_diff <= XFS_INLINE_EXTS) { > - if (idx < nextents) { > - memmove(&ifp->if_u2.if_inline_ext[idx + ext_diff], > - &ifp->if_u2.if_inline_ext[idx], > - (nextents - idx) * sizeof(xfs_bmbt_rec_t)); > - memset(&ifp->if_u2.if_inline_ext[idx], 0, byte_diff); > - } > - ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext; > - ifp->if_real_bytes = 0; > - } > - /* > - * Otherwise use a linear (direct) extent list. > + * Use a linear (direct) extent list. > * If the extents are currently inside the inode, > * xfs_iext_realloc_direct will switch us from > * inline to direct extent allocation mode. > */ > - else if (nextents + ext_diff <= XFS_LINEAR_EXTS) { > + if (nextents + ext_diff <= XFS_LINEAR_EXTS) { > xfs_iext_realloc_direct(ifp, new_size); > if (idx < nextents) { > memmove(&ifp->if_u1.if_extents[idx + ext_diff], > @@ -1172,43 +1116,10 @@ xfs_iext_remove( > xfs_iext_remove_indirect(ifp, cur->idx, ext_diff); > } else if (ifp->if_real_bytes) { > xfs_iext_remove_direct(ifp, cur->idx, ext_diff); > - } else { > - xfs_iext_remove_inline(ifp, cur->idx, ext_diff); > } > ifp->if_bytes = new_size; > } > > -/* > - * This removes ext_diff extents from the inline buffer, beginning > - * at extent index idx. > - */ > -void > -xfs_iext_remove_inline( > - xfs_ifork_t *ifp, /* inode fork pointer */ > - xfs_extnum_t idx, /* index to begin removing exts */ > - int ext_diff) /* number of extents to remove */ > -{ > - int nextents; /* number of extents in file */ > - > - ASSERT(!(ifp->if_flags & XFS_IFEXTIREC)); > - ASSERT(idx < XFS_INLINE_EXTS); > - nextents = xfs_iext_count(ifp); > - ASSERT(((nextents - ext_diff) > 0) && > - (nextents - ext_diff) < XFS_INLINE_EXTS); > - > - if (idx + ext_diff < nextents) { > - memmove(&ifp->if_u2.if_inline_ext[idx], > - &ifp->if_u2.if_inline_ext[idx + ext_diff], > - (nextents - (idx + ext_diff)) * > - sizeof(xfs_bmbt_rec_t)); > - memset(&ifp->if_u2.if_inline_ext[nextents - ext_diff], > - 0, ext_diff * sizeof(xfs_bmbt_rec_t)); > - } else { > - memset(&ifp->if_u2.if_inline_ext[idx], 0, > - ext_diff * sizeof(xfs_bmbt_rec_t)); > - } > -} > - > /* > * This removes ext_diff extents from a linear (direct) extent list, > * beginning at extent index idx. If the extents are being removed > @@ -1351,16 +1262,7 @@ xfs_iext_realloc_direct( > /* Free extent records */ > if (new_size == 0) { > xfs_iext_destroy(ifp); > - } > - /* Resize direct extent list and zero any new bytes */ > - else if (ifp->if_real_bytes) { > - /* Check if extents will fit inside the inode */ > - if (new_size <= XFS_INLINE_EXTS * sizeof(xfs_bmbt_rec_t)) { > - xfs_iext_direct_to_inline(ifp, new_size / > - (uint)sizeof(xfs_bmbt_rec_t)); > - ifp->if_bytes = new_size; > - return; > - } > + } else { > if (!is_power_of_2(new_size)){ > rnew_size = roundup_pow_of_two(new_size); > } > @@ -1375,63 +1277,10 @@ xfs_iext_realloc_direct( > rnew_size - ifp->if_real_bytes); > } > } > - /* Switch from the inline extent buffer to a direct extent list */ > - else { > - if (!is_power_of_2(new_size)) { > - rnew_size = roundup_pow_of_two(new_size); > - } > - xfs_iext_inline_to_direct(ifp, rnew_size); > - } > ifp->if_real_bytes = rnew_size; > ifp->if_bytes = new_size; > } > > -/* > - * Switch from linear (direct) extent records to inline buffer. > - */ > -void > -xfs_iext_direct_to_inline( > - xfs_ifork_t *ifp, /* inode fork pointer */ > - xfs_extnum_t nextents) /* number of extents in file */ > -{ > - ASSERT(ifp->if_flags & XFS_IFEXTENTS); > - ASSERT(nextents <= XFS_INLINE_EXTS); > - /* > - * The inline buffer was zeroed when we switched > - * from inline to direct extent allocation mode, > - * so we don't need to clear it here. > - */ > - memcpy(ifp->if_u2.if_inline_ext, ifp->if_u1.if_extents, > - nextents * sizeof(xfs_bmbt_rec_t)); > - kmem_free(ifp->if_u1.if_extents); > - ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext; > - ifp->if_real_bytes = 0; > -} > - > -/* > - * Switch from inline buffer to linear (direct) extent records. > - * new_size should already be rounded up to the next power of 2 > - * by the caller (when appropriate), so use new_size as it is. > - * However, since new_size may be rounded up, we can't update > - * if_bytes here. It is the caller's responsibility to update > - * if_bytes upon return. > - */ > -void > -xfs_iext_inline_to_direct( > - xfs_ifork_t *ifp, /* inode fork pointer */ > - int new_size) /* number of extents in file */ > -{ > - ifp->if_u1.if_extents = kmem_alloc(new_size, KM_NOFS); > - memset(ifp->if_u1.if_extents, 0, new_size); > - if (ifp->if_bytes) { > - memcpy(ifp->if_u1.if_extents, ifp->if_u2.if_inline_ext, > - ifp->if_bytes); > - memset(ifp->if_u2.if_inline_ext, 0, XFS_INLINE_EXTS * > - sizeof(xfs_bmbt_rec_t)); > - } > - ifp->if_real_bytes = new_size; > -} > - > /* > * Resize an extent indirection array to new_size bytes. > */ > @@ -1511,9 +1360,6 @@ xfs_iext_destroy( > xfs_iext_irec_remove_all(ifp); > } else if (ifp->if_real_bytes) { > kmem_free(ifp->if_u1.if_extents); > - } else if (ifp->if_bytes) { > - memset(ifp->if_u2.if_inline_ext, 0, XFS_INLINE_EXTS * > - sizeof(xfs_bmbt_rec_t)); > } > ifp->if_u1.if_extents = NULL; > ifp->if_real_bytes = 0; > @@ -1708,8 +1554,6 @@ xfs_iext_irec_init( > > if (nextents == 0) { > ifp->if_u1.if_extents = kmem_alloc(XFS_IEXT_BUFSZ, KM_NOFS); > - } else if (!ifp->if_real_bytes) { > - xfs_iext_inline_to_direct(ifp, XFS_IEXT_BUFSZ); > } else if (ifp->if_real_bytes < XFS_IEXT_BUFSZ) { > xfs_iext_realloc_direct(ifp, XFS_IEXT_BUFSZ); > } > @@ -1829,9 +1673,6 @@ xfs_iext_irec_compact( > > if (nextents == 0) { > xfs_iext_destroy(ifp); > - } else if (nextents <= XFS_INLINE_EXTS) { > - xfs_iext_indirect_to_direct(ifp); > - xfs_iext_direct_to_inline(ifp, nextents); > } else if (nextents <= XFS_LINEAR_EXTS) { > xfs_iext_indirect_to_direct(ifp); > } else if (nextents < (nlists * XFS_LINEAR_EXTS) >> 1) { > diff --git a/fs/xfs/libxfs/xfs_inode_fork.h b/fs/xfs/libxfs/xfs_inode_fork.h > index dc347dd9dc78..508f13784334 100644 > --- a/fs/xfs/libxfs/xfs_inode_fork.h > +++ b/fs/xfs/libxfs/xfs_inode_fork.h > @@ -51,8 +51,6 @@ typedef struct xfs_ext_irec { > */ > #define XFS_IEXT_BUFSZ 4096 > #define XFS_LINEAR_EXTS (XFS_IEXT_BUFSZ / (uint)sizeof(xfs_bmbt_rec_t)) > -#define XFS_INLINE_EXTS 2 > -#define XFS_INLINE_DATA 32 > typedef struct xfs_ifork { > int if_bytes; /* bytes in if_u1 */ > int if_real_bytes; /* bytes allocated in if_u1 */ > @@ -64,12 +62,6 @@ typedef struct xfs_ifork { > xfs_ext_irec_t *if_ext_irec; /* irec map file exts */ > char *if_data; /* inline file data */ > } if_u1; > - union { > - xfs_bmbt_rec_host_t if_inline_ext[XFS_INLINE_EXTS]; > - /* very small file extents */ > - char if_inline_data[XFS_INLINE_DATA]; > - /* very small file data */ > - } if_u2; > } xfs_ifork_t; > > /* > @@ -158,12 +150,9 @@ void xfs_iext_add_indirect_multi(struct xfs_ifork *, int, > xfs_extnum_t, int); > void xfs_iext_remove(struct xfs_inode *, struct xfs_iext_cursor *, > int, int); > -void xfs_iext_remove_inline(struct xfs_ifork *, xfs_extnum_t, int); > void xfs_iext_remove_direct(struct xfs_ifork *, xfs_extnum_t, int); > void xfs_iext_remove_indirect(struct xfs_ifork *, xfs_extnum_t, int); > void xfs_iext_realloc_direct(struct xfs_ifork *, int); > -void xfs_iext_direct_to_inline(struct xfs_ifork *, xfs_extnum_t); > -void xfs_iext_inline_to_direct(struct xfs_ifork *, int); > void xfs_iext_destroy(struct xfs_ifork *); > struct xfs_bmbt_rec_host * > xfs_iext_bno_to_ext(struct xfs_ifork *, xfs_fileoff_t, int *); > diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c > index b6b954d5cf54..c2f8e40a3e1f 100644 > --- a/fs/xfs/xfs_bmap_util.c > +++ b/fs/xfs/xfs_bmap_util.c > @@ -1709,7 +1709,6 @@ xfs_swap_extent_forks( > xfs_filblks_t aforkblks = 0; > xfs_filblks_t taforkblks = 0; > xfs_extnum_t junk; > - xfs_extnum_t nextents; > uint64_t tmp; > int error; > > @@ -1784,13 +1783,6 @@ xfs_swap_extent_forks( > > switch (ip->i_d.di_format) { > case XFS_DINODE_FMT_EXTENTS: > - /* > - * If the extents fit in the inode, fix the pointer. Otherwise > - * it's already NULL or pointing to the extent. > - */ > - nextents = xfs_iext_count(&ip->i_df); > - if (nextents <= XFS_INLINE_EXTS) > - ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext; > (*src_log_flags) |= XFS_ILOG_DEXT; > break; > case XFS_DINODE_FMT_BTREE: > @@ -1802,13 +1794,6 @@ xfs_swap_extent_forks( > > switch (tip->i_d.di_format) { > case XFS_DINODE_FMT_EXTENTS: > - /* > - * If the extents fit in the inode, fix the pointer. Otherwise > - * it's already NULL or pointing to the extent. > - */ > - nextents = xfs_iext_count(&tip->i_df); > - if (nextents <= XFS_INLINE_EXTS) > - tifp->if_u1.if_extents = tifp->if_u2.if_inline_ext; > (*target_log_flags) |= XFS_ILOG_DEXT; > break; > case XFS_DINODE_FMT_BTREE: > -- > 2.14.2 > > -- > 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