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- gc USE_BUFHASH. The smp locking of the buf cache renders this useless.

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This commit is contained in:
Jeff Roberson 2003-03-01 05:55:03 +00:00
parent 59c9bb54ee
commit bff5362bf2
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=111694
3 changed files with 0 additions and 111 deletions
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104
sys/kern/vfs_bio.c
View File

@ -212,28 +212,6 @@ static int needsbuffer;
*/
static struct mtx nblock;
#ifdef USE_BUFHASH
/*
* Mask for index into the buffer hash table, which needs to be power of 2 in
* size. Set in kern_vfs_bio_buffer_alloc.
*/
static int bufhashmask;
/*
* Hash table for all buffers, with a linked list hanging from each table
* entry. Set in kern_vfs_bio_buffer_alloc, initialized in buf_init.
*/
static LIST_HEAD(bufhashhdr, buf) *bufhashtbl;
/*
* Somewhere to store buffers when they are not in another list, to always
* have them in a list (and thus being able to use the same set of operations
* on them.)
*/
static struct bufhashhdr invalhash;
#endif
/*
* Definitions for the buffer free lists.
*/
@ -263,21 +241,6 @@ const char *buf_wmesg = BUF_WMESG;
#define VFS_BIO_NEED_FREE 0x04 /* wait for free bufs, hi hysteresis */
#define VFS_BIO_NEED_BUFSPACE 0x08 /* wait for buf space, lo hysteresis */
#ifdef USE_BUFHASH
/*
* Buffer hash table code. Note that the logical block scans linearly, which
* gives us some L1 cache locality.
*/
static __inline
struct bufhashhdr *
bufhash(struct vnode *vnp, daddr_t bn)
{
return(&bufhashtbl[(((uintptr_t)(vnp) >> 7) + (int)bn) & bufhashmask]);
}
#endif
/*
* numdirtywakeup:
*
@ -504,16 +467,6 @@ kern_vfs_bio_buffer_alloc(caddr_t v, long physmem_est)
buf = (void *)v;
v = (caddr_t)(buf + nbuf);
#ifdef USE_BUFHASH
/*
* Calculate the hash table size and reserve space
*/
for (bufhashmask = 8; bufhashmask < nbuf / 4; bufhashmask <<= 1)
;
bufhashtbl = (void *)v;
v = (caddr_t)(bufhashtbl + bufhashmask);
--bufhashmask;
#endif
return(v);
}
@ -527,19 +480,11 @@ bufinit(void)
GIANT_REQUIRED;
#ifdef USE_BUFHASH
LIST_INIT(&invalhash);
#endif
mtx_init(&bqlock, "buf queue lock", NULL, MTX_DEF);
mtx_init(&rbreqlock, "runningbufspace lock", NULL, MTX_DEF);
mtx_init(&nblock, "needsbuffer lock", NULL, MTX_DEF);
mtx_init(&bdlock, "buffer daemon lock", NULL, MTX_DEF);
#ifdef USE_BUFHASH
for (i = 0; i <= bufhashmask; i++)
LIST_INIT(&bufhashtbl[i]);
#endif
/* next, make a null set of free lists */
for (i = 0; i < BUFFER_QUEUES; i++)
TAILQ_INIT(&bufqueues[i]);
@ -558,9 +503,6 @@ bufinit(void)
LIST_INIT(&bp->b_dep);
BUF_LOCKINIT(bp);
TAILQ_INSERT_TAIL(&bufqueues[QUEUE_EMPTY], bp, b_freelist);
#ifdef USE_BUFHASH
LIST_INSERT_HEAD(&invalhash, bp, b_hash);
#endif
}
/*
@ -1438,10 +1380,6 @@ brelse(struct buf * bp)
bp->b_qindex = QUEUE_EMPTY;
}
TAILQ_INSERT_HEAD(&bufqueues[bp->b_qindex], bp, b_freelist);
#ifdef USE_BUFHASH
LIST_REMOVE(bp, b_hash);
LIST_INSERT_HEAD(&invalhash, bp, b_hash);
#endif
bp->b_dev = NODEV;
/* buffers with junk contents */
} else if (bp->b_flags & (B_INVAL | B_NOCACHE | B_RELBUF) ||
@ -1452,10 +1390,6 @@ brelse(struct buf * bp)
panic("losing buffer 2");
bp->b_qindex = QUEUE_CLEAN;
TAILQ_INSERT_HEAD(&bufqueues[QUEUE_CLEAN], bp, b_freelist);
#ifdef USE_BUFHASH
LIST_REMOVE(bp, b_hash);
LIST_INSERT_HEAD(&invalhash, bp, b_hash);
#endif
bp->b_dev = NODEV;
/* buffers that are locked */
@ -1644,32 +1578,6 @@ vfs_vmio_release(bp)
brelvp(bp);
}
#ifdef USE_BUFHASH
/*
* XXX MOVED TO VFS_SUBR.C
*
* Check to see if a block is currently memory resident.
*/
struct buf *
gbincore(struct vnode * vp, daddr_t blkno)
{
struct buf *bp;
struct bufhashhdr *bh;
bh = bufhash(vp, blkno);
/* Search hash chain */
LIST_FOREACH(bp, bh, b_hash) {
/* hit */
if (bp->b_vp == vp && bp->b_lblkno == blkno &&
(bp->b_flags & B_INVAL) == 0) {
break;
}
}
return (bp);
}
#endif
/*
* Check to see if a block at a particular lbn is available for a clustered
* write.
@ -1961,10 +1869,6 @@ getnewbuf(int slpflag, int slptimeo, int size, int maxsize)
buf_deallocate(bp);
if (bp->b_xflags & BX_BKGRDINPROG)
panic("losing buffer 3");
#ifdef USE_BUFHASH
LIST_REMOVE(bp, b_hash);
LIST_INSERT_HEAD(&invalhash, bp, b_hash);
#endif
if (bp->b_bufsize)
allocbuf(bp, 0);
@ -2465,9 +2369,6 @@ getblk(struct vnode * vp, daddr_t blkno, int size, int slpflag, int slptimeo)
struct buf *bp;
int s;
int error;
#ifdef USE_BUFHASH
struct bufhashhdr *bh;
#endif
ASSERT_VOP_LOCKED(vp, "getblk");
if (size > MAXBSIZE)
@ -2663,11 +2564,6 @@ getblk(struct vnode * vp, daddr_t blkno, int size, int slpflag, int slptimeo)
bp->b_offset = offset;
bgetvp(vp, bp);
#ifdef USE_BUFHASH
LIST_REMOVE(bp, b_hash);
bh = bufhash(vp, blkno);
LIST_INSERT_HEAD(bh, bp, b_hash);
#endif
/*
* set B_VMIO bit. allocbuf() the buffer bigger. Since the

4
sys/kern/vfs_subr.c
View File

@ -1554,8 +1554,6 @@ buf_vlist_add(struct buf *bp, struct vnode *vp, b_xflags_t xflags)
}
}
#ifndef USE_BUFHASH
/*
* Lookup a buffer using the splay tree. Note that we specifically avoid
* shadow buffers used in background bitmap writes.
@ -1580,8 +1578,6 @@ gbincore(struct vnode *vp, daddr_t lblkno)
return(NULL);
}
#endif
/*
* Associate a buffer with a vnode.
*/

3
sys/sys/buf.h
View File

@ -124,9 +124,6 @@ struct buf {
#define B_MAGIC_NFS 0x67238234
void (*b_iodone)(struct buf *);
off_t b_offset; /* Offset into file. */
#ifdef USE_BUFHASH
LIST_ENTRY(buf) b_hash; /* Hash chain. */
#endif
TAILQ_ENTRY(buf) b_vnbufs; /* (V) Buffer's associated vnode. */
struct buf *b_left; /* (V) splay tree link */
struct buf *b_right; /* (V) splay tree link */