kernel_optimize_test/fs/xfs/quota/xfs_dquot.h
Peter Leckie bc3048e3cd [XFS] Clean up dquot pincount code.
This is a code cleanup and optimization that removes a per mount point
spinlock from the quota code and cleans up the code.

The patch changes the pincount from being an int protected by a spinlock
to an atomic_t allowing the pincount to be manipulated without holding the
spinlock.

This cleanup also protects against random wakup's of both the aild and
xfssyncd by reevaluating the pincount after been woken. Two latter patches
will address the Spurious wakeups.

SGI-PV: 986789

SGI-Modid: xfs-linux-melb:xfs-kern:32215a

Signed-off-by: Peter Leckie <pleckie@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-10-30 17:05:04 +11:00

193 lines
6.3 KiB
C

/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __XFS_DQUOT_H__
#define __XFS_DQUOT_H__
/*
* Dquots are structures that hold quota information about a user or a group,
* much like inodes are for files. In fact, dquots share many characteristics
* with inodes. However, dquots can also be a centralized resource, relative
* to a collection of inodes. In this respect, dquots share some characteristics
* of the superblock.
* XFS dquots exploit both those in its algorithms. They make every attempt
* to not be a bottleneck when quotas are on and have minimal impact, if any,
* when quotas are off.
*/
/*
* The hash chain headers (hash buckets)
*/
typedef struct xfs_dqhash {
struct xfs_dquot *qh_next;
mutex_t qh_lock;
uint qh_version; /* ever increasing version */
uint qh_nelems; /* number of dquots on the list */
} xfs_dqhash_t;
typedef struct xfs_dqlink {
struct xfs_dquot *ql_next; /* forward link */
struct xfs_dquot **ql_prevp; /* pointer to prev ql_next */
} xfs_dqlink_t;
struct xfs_mount;
struct xfs_trans;
/*
* This is the marker which is designed to occupy the first few
* bytes of the xfs_dquot_t structure. Even inside this, the freelist pointers
* must come first.
* This serves as the marker ("sentinel") when we have to restart list
* iterations because of locking considerations.
*/
typedef struct xfs_dqmarker {
struct xfs_dquot*dqm_flnext; /* link to freelist: must be first */
struct xfs_dquot*dqm_flprev;
xfs_dqlink_t dqm_mplist; /* link to mount's list of dquots */
xfs_dqlink_t dqm_hashlist; /* link to the hash chain */
uint dqm_flags; /* various flags (XFS_DQ_*) */
} xfs_dqmarker_t;
/*
* The incore dquot structure
*/
typedef struct xfs_dquot {
xfs_dqmarker_t q_lists; /* list ptrs, q_flags (marker) */
xfs_dqhash_t *q_hash; /* the hashchain header */
struct xfs_mount*q_mount; /* filesystem this relates to */
struct xfs_trans*q_transp; /* trans this belongs to currently */
uint q_nrefs; /* # active refs from inodes */
xfs_daddr_t q_blkno; /* blkno of dquot buffer */
int q_bufoffset; /* off of dq in buffer (# dquots) */
xfs_fileoff_t q_fileoffset; /* offset in quotas file */
struct xfs_dquot*q_gdquot; /* group dquot, hint only */
xfs_disk_dquot_t q_core; /* actual usage & quotas */
xfs_dq_logitem_t q_logitem; /* dquot log item */
xfs_qcnt_t q_res_bcount; /* total regular nblks used+reserved */
xfs_qcnt_t q_res_icount; /* total inos allocd+reserved */
xfs_qcnt_t q_res_rtbcount;/* total realtime blks used+reserved */
mutex_t q_qlock; /* quota lock */
struct completion q_flush; /* flush completion queue */
atomic_t q_pincount; /* dquot pin count */
wait_queue_head_t q_pinwait; /* dquot pinning wait queue */
#ifdef XFS_DQUOT_TRACE
struct ktrace *q_trace; /* trace header structure */
#endif
} xfs_dquot_t;
#define dq_flnext q_lists.dqm_flnext
#define dq_flprev q_lists.dqm_flprev
#define dq_mplist q_lists.dqm_mplist
#define dq_hashlist q_lists.dqm_hashlist
#define dq_flags q_lists.dqm_flags
#define XFS_DQHOLD(dqp) ((dqp)->q_nrefs++)
#ifdef DEBUG
static inline int
XFS_DQ_IS_LOCKED(xfs_dquot_t *dqp)
{
if (mutex_trylock(&dqp->q_qlock)) {
mutex_unlock(&dqp->q_qlock);
return 0;
}
return 1;
}
#endif
/*
* Manage the q_flush completion queue embedded in the dquot. This completion
* queue synchronizes processes attempting to flush the in-core dquot back to
* disk.
*/
static inline void xfs_dqflock(xfs_dquot_t *dqp)
{
wait_for_completion(&dqp->q_flush);
}
static inline int xfs_dqflock_nowait(xfs_dquot_t *dqp)
{
return try_wait_for_completion(&dqp->q_flush);
}
static inline void xfs_dqfunlock(xfs_dquot_t *dqp)
{
complete(&dqp->q_flush);
}
#define XFS_DQ_IS_ON_FREELIST(dqp) ((dqp)->dq_flnext != (dqp))
#define XFS_DQ_IS_DIRTY(dqp) ((dqp)->dq_flags & XFS_DQ_DIRTY)
#define XFS_QM_ISUDQ(dqp) ((dqp)->dq_flags & XFS_DQ_USER)
#define XFS_QM_ISPDQ(dqp) ((dqp)->dq_flags & XFS_DQ_PROJ)
#define XFS_QM_ISGDQ(dqp) ((dqp)->dq_flags & XFS_DQ_GROUP)
#define XFS_DQ_TO_QINF(dqp) ((dqp)->q_mount->m_quotainfo)
#define XFS_DQ_TO_QIP(dqp) (XFS_QM_ISUDQ(dqp) ? \
XFS_DQ_TO_QINF(dqp)->qi_uquotaip : \
XFS_DQ_TO_QINF(dqp)->qi_gquotaip)
#define XFS_IS_THIS_QUOTA_OFF(d) (! (XFS_QM_ISUDQ(d) ? \
(XFS_IS_UQUOTA_ON((d)->q_mount)) : \
(XFS_IS_OQUOTA_ON((d)->q_mount))))
#ifdef XFS_DQUOT_TRACE
/*
* Dquot Tracing stuff.
*/
#define DQUOT_TRACE_SIZE 64
#define DQUOT_KTRACE_ENTRY 1
extern void __xfs_dqtrace_entry(xfs_dquot_t *dqp, char *func,
void *, xfs_inode_t *);
#define xfs_dqtrace_entry_ino(a,b,ip) \
__xfs_dqtrace_entry((a), (b), (void*)__return_address, (ip))
#define xfs_dqtrace_entry(a,b) \
__xfs_dqtrace_entry((a), (b), (void*)__return_address, NULL)
#else
#define xfs_dqtrace_entry(a,b)
#define xfs_dqtrace_entry_ino(a,b,ip)
#endif
#ifdef QUOTADEBUG
extern void xfs_qm_dqprint(xfs_dquot_t *);
#else
#define xfs_qm_dqprint(a)
#endif
extern void xfs_qm_dqdestroy(xfs_dquot_t *);
extern int xfs_qm_dqflush(xfs_dquot_t *, uint);
extern int xfs_qm_dqpurge(xfs_dquot_t *);
extern void xfs_qm_dqunpin_wait(xfs_dquot_t *);
extern int xfs_qm_dqlock_nowait(xfs_dquot_t *);
extern void xfs_qm_dqflock_pushbuf_wait(xfs_dquot_t *dqp);
extern void xfs_qm_adjust_dqtimers(xfs_mount_t *,
xfs_disk_dquot_t *);
extern void xfs_qm_adjust_dqlimits(xfs_mount_t *,
xfs_disk_dquot_t *);
extern int xfs_qm_dqget(xfs_mount_t *, xfs_inode_t *,
xfs_dqid_t, uint, uint, xfs_dquot_t **);
extern void xfs_qm_dqput(xfs_dquot_t *);
extern void xfs_qm_dqrele(xfs_dquot_t *);
extern void xfs_dqlock(xfs_dquot_t *);
extern void xfs_dqlock2(xfs_dquot_t *, xfs_dquot_t *);
extern void xfs_dqunlock(xfs_dquot_t *);
extern void xfs_dqunlock_nonotify(xfs_dquot_t *);
#endif /* __XFS_DQUOT_H__ */