From e98c414f9a3134fe7efc56ef8f1d394b54bfd40e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 23 Jun 2010 18:11:15 +1000 Subject: xfs: simplify log item descriptor tracking Currently we track log item descriptor belonging to a transaction using a complex opencoded chunk allocator. This code has been there since day one and seems to work around the lack of an efficient slab allocator. This patch replaces it with dynamically allocated log item descriptors from a dedicated slab pool, linked to the transaction by a linked list. This allows to greatly simplify the log item descriptor tracking to the point where it's just a couple hundred lines in xfs_trans.c instead of a separate file. The external API has also been simplified while we're at it - the xfs_trans_add_item and xfs_trans_del_item functions to add/ delete items from a transaction have been simplified to the bare minium, and the xfs_trans_find_item function is replaced with a direct dereference of the li_desc field. All debug code walking the list of log items in a transaction is down to a simple list_for_each_entry. Note that we could easily use a singly linked list here instead of the double linked list from list.h as the fastpath only does deletion from sequential traversal. But given that we don't have one available as a library function yet I use the list.h functions for simplicity. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner --- fs/xfs/xfs_trans.h | 105 ++++------------------------------------------------- 1 file changed, 7 insertions(+), 98 deletions(-) (limited to 'fs/xfs/xfs_trans.h') diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h index e639e8e9a2a9..0c903eb8bbe1 100644 --- a/fs/xfs/xfs_trans.h +++ b/fs/xfs/xfs_trans.h @@ -161,105 +161,14 @@ typedef struct xfs_trans_header { * the amount of space needed to log the item it describes * once we get to commit processing (see xfs_trans_commit()). */ -typedef struct xfs_log_item_desc { +struct xfs_log_item_desc { struct xfs_log_item *lid_item; - ushort lid_size; - unsigned char lid_flags; - unsigned char lid_index; -} xfs_log_item_desc_t; + ushort lid_size; + unsigned char lid_flags; + struct list_head lid_trans; +}; #define XFS_LID_DIRTY 0x1 -#define XFS_LID_PINNED 0x2 - -/* - * This structure is used to maintain a chunk list of log_item_desc - * structures. The free field is a bitmask indicating which descriptors - * in this chunk's array are free. The unused field is the first value - * not used since this chunk was allocated. - */ -#define XFS_LIC_NUM_SLOTS 15 -typedef struct xfs_log_item_chunk { - struct xfs_log_item_chunk *lic_next; - ushort lic_free; - ushort lic_unused; - xfs_log_item_desc_t lic_descs[XFS_LIC_NUM_SLOTS]; -} xfs_log_item_chunk_t; - -#define XFS_LIC_MAX_SLOT (XFS_LIC_NUM_SLOTS - 1) -#define XFS_LIC_FREEMASK ((1 << XFS_LIC_NUM_SLOTS) - 1) - - -/* - * Initialize the given chunk. Set the chunk's free descriptor mask - * to indicate that all descriptors are free. The caller gets to set - * lic_unused to the right value (0 matches all free). The - * lic_descs.lid_index values are set up as each desc is allocated. - */ -static inline void xfs_lic_init(xfs_log_item_chunk_t *cp) -{ - cp->lic_free = XFS_LIC_FREEMASK; -} - -static inline void xfs_lic_init_slot(xfs_log_item_chunk_t *cp, int slot) -{ - cp->lic_descs[slot].lid_index = (unsigned char)(slot); -} - -static inline int xfs_lic_vacancy(xfs_log_item_chunk_t *cp) -{ - return cp->lic_free & XFS_LIC_FREEMASK; -} - -static inline void xfs_lic_all_free(xfs_log_item_chunk_t *cp) -{ - cp->lic_free = XFS_LIC_FREEMASK; -} - -static inline int xfs_lic_are_all_free(xfs_log_item_chunk_t *cp) -{ - return ((cp->lic_free & XFS_LIC_FREEMASK) == XFS_LIC_FREEMASK); -} - -static inline int xfs_lic_isfree(xfs_log_item_chunk_t *cp, int slot) -{ - return (cp->lic_free & (1 << slot)); -} - -static inline void xfs_lic_claim(xfs_log_item_chunk_t *cp, int slot) -{ - cp->lic_free &= ~(1 << slot); -} - -static inline void xfs_lic_relse(xfs_log_item_chunk_t *cp, int slot) -{ - cp->lic_free |= 1 << slot; -} - -static inline xfs_log_item_desc_t * -xfs_lic_slot(xfs_log_item_chunk_t *cp, int slot) -{ - return &(cp->lic_descs[slot]); -} - -static inline int xfs_lic_desc_to_slot(xfs_log_item_desc_t *dp) -{ - return (uint)dp->lid_index; -} - -/* - * Calculate the address of a chunk given a descriptor pointer: - * dp - dp->lid_index give the address of the start of the lic_descs array. - * From this we subtract the offset of the lic_descs field in a chunk. - * All of this yields the address of the chunk, which is - * cast to a chunk pointer. - */ -static inline xfs_log_item_chunk_t * -xfs_lic_desc_to_chunk(xfs_log_item_desc_t *dp) -{ - return (xfs_log_item_chunk_t*) \ - (((xfs_caddr_t)((dp) - (dp)->lid_index)) - \ - (xfs_caddr_t)(((xfs_log_item_chunk_t*)0)->lic_descs)); -} #define XFS_TRANS_MAGIC 0x5452414E /* 'TRAN' */ /* @@ -516,8 +425,7 @@ typedef struct xfs_trans { int64_t t_rblocks_delta;/* superblock rblocks change */ int64_t t_rextents_delta;/* superblocks rextents chg */ int64_t t_rextslog_delta;/* superblocks rextslog chg */ - unsigned int t_items_free; /* log item descs free */ - xfs_log_item_chunk_t t_items; /* first log item desc chunk */ + struct list_head t_items; /* log item descriptors */ xfs_trans_header_t t_header; /* header for in-log trans */ struct list_head t_busy; /* list of busy extents */ unsigned long t_pflags; /* saved process flags state */ @@ -595,6 +503,7 @@ int xfs_trans_ail_init(struct xfs_mount *); void xfs_trans_ail_destroy(struct xfs_mount *); extern kmem_zone_t *xfs_trans_zone; +extern kmem_zone_t *xfs_log_item_desc_zone; #endif /* __KERNEL__ */ -- cgit v1.2.2 From 9412e3181c0ef82efc3d8e88d73e583ec10c34e9 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 23 Jun 2010 18:11:15 +1000 Subject: xfs: merge iop_unpin_remove into iop_unpin The unpin_remove item operation instances always share most of the implementation with the respective unpin implementation. So instead of keeping two different entry points add a remove flag to the unpin operation and share the code more easily. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner --- fs/xfs/xfs_trans.h | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'fs/xfs/xfs_trans.h') diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h index 0c903eb8bbe1..37c0ce1ccd48 100644 --- a/fs/xfs/xfs_trans.h +++ b/fs/xfs/xfs_trans.h @@ -347,8 +347,7 @@ typedef struct xfs_item_ops { uint (*iop_size)(xfs_log_item_t *); void (*iop_format)(xfs_log_item_t *, struct xfs_log_iovec *); void (*iop_pin)(xfs_log_item_t *); - void (*iop_unpin)(xfs_log_item_t *); - void (*iop_unpin_remove)(xfs_log_item_t *, struct xfs_trans *); + void (*iop_unpin)(xfs_log_item_t *, int remove); uint (*iop_trylock)(xfs_log_item_t *); void (*iop_unlock)(xfs_log_item_t *); xfs_lsn_t (*iop_committed)(xfs_log_item_t *, xfs_lsn_t); @@ -360,8 +359,7 @@ typedef struct xfs_item_ops { #define IOP_SIZE(ip) (*(ip)->li_ops->iop_size)(ip) #define IOP_FORMAT(ip,vp) (*(ip)->li_ops->iop_format)(ip, vp) #define IOP_PIN(ip) (*(ip)->li_ops->iop_pin)(ip) -#define IOP_UNPIN(ip) (*(ip)->li_ops->iop_unpin)(ip) -#define IOP_UNPIN_REMOVE(ip,tp) (*(ip)->li_ops->iop_unpin_remove)(ip, tp) +#define IOP_UNPIN(ip, remove) (*(ip)->li_ops->iop_unpin)(ip, remove) #define IOP_TRYLOCK(ip) (*(ip)->li_ops->iop_trylock)(ip) #define IOP_UNLOCK(ip) (*(ip)->li_ops->iop_unlock)(ip) #define IOP_COMMITTED(ip, lsn) (*(ip)->li_ops->iop_committed)(ip, lsn) -- cgit v1.2.2 From 898621d5a72c6799a9a13fce20443b4b6699899c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 24 Jun 2010 11:36:58 +1000 Subject: xfs: simplify inode to transaction joining Currently we need to either call IHOLD or xfs_trans_ihold on an inode when joining it to a transaction via xfs_trans_ijoin. This patches instead makes xfs_trans_ijoin usable on it's own by doing an implicity xfs_trans_ihold, which also allows us to drop the third argument. For the case where we want to hold a reference on the inode a xfs_trans_ijoin_ref wrapper is added which does the IHOLD and marks the inode for needing an xfs_iput. In addition to the cleaner interface to the caller this also simplifies the implementation. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner --- fs/xfs/xfs_trans.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/xfs/xfs_trans.h') diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h index 37c0ce1ccd48..aa6f422f0361 100644 --- a/fs/xfs/xfs_trans.h +++ b/fs/xfs/xfs_trans.h @@ -475,8 +475,8 @@ void xfs_trans_dquot_buf(xfs_trans_t *, struct xfs_buf *, uint); void xfs_trans_inode_alloc_buf(xfs_trans_t *, struct xfs_buf *); int xfs_trans_iget(struct xfs_mount *, xfs_trans_t *, xfs_ino_t , uint, uint, struct xfs_inode **); -void xfs_trans_ijoin(xfs_trans_t *, struct xfs_inode *, uint); -void xfs_trans_ihold(xfs_trans_t *, struct xfs_inode *); +void xfs_trans_ijoin_ref(struct xfs_trans *, struct xfs_inode *, uint); +void xfs_trans_ijoin(struct xfs_trans *, struct xfs_inode *); void xfs_trans_log_buf(xfs_trans_t *, struct xfs_buf *, uint, uint); void xfs_trans_log_inode(xfs_trans_t *, struct xfs_inode *, uint); struct xfs_efi_log_item *xfs_trans_get_efi(xfs_trans_t *, uint); -- cgit v1.2.2 From a59f55703c3725b2fa582924f51db62b58be05bb Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 23 Jun 2010 18:11:15 +1000 Subject: xfs: remove the unused XFS_TRANS_NOSLEEP/XFS_TRANS_WAIT flags Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner --- fs/xfs/xfs_trans.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'fs/xfs/xfs_trans.h') diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h index aa6f422f0361..c13c0f97b494 100644 --- a/fs/xfs/xfs_trans.h +++ b/fs/xfs/xfs_trans.h @@ -184,8 +184,6 @@ struct xfs_log_item_desc { /* * Values for call flags parameter. */ -#define XFS_TRANS_NOSLEEP 0x1 -#define XFS_TRANS_WAIT 0x2 #define XFS_TRANS_RELEASE_LOG_RES 0x4 #define XFS_TRANS_ABORT 0x8 -- cgit v1.2.2