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vfs_cluster.c:

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Various more tweaks from John Dyson to improve read ahead calculations.

vfs_subr.c:
Only wakeup if numoutput is 0 in vwakeup().

Submitted by:	John Dyson
This commit is contained in:
David Greenman 1995-02-22 09:39:22 +00:00
parent 701d45805b
commit a3a8bb29d2
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=6621
3 changed files with 22 additions and 21 deletions
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35
sys/kern/vfs_cluster.c
View File

@ -33,7 +33,7 @@
* SUCH DAMAGE.
*
* @(#)vfs_cluster.c 8.7 (Berkeley) 2/13/94
* $Id: vfs_cluster.c,v 1.8 1995/01/09 16:04:53 davidg Exp $
* $Id: vfs_cluster.c,v 1.9 1995/01/24 10:00:46 davidg Exp $
*/
#include <sys/param.h>
@ -47,6 +47,8 @@
#include <sys/resourcevar.h>
#include <sys/vmmeter.h>
#include <miscfs/specfs/specdev.h>
#include <vm/vm.h>
#include <vm/vm_pageout.h>
#ifdef DEBUG
#include <vm/vm.h>
@ -131,13 +133,15 @@ cluster_read(vp, filesize, lblkno, size, cred, bpp)
int i;
if (!ISSEQREAD(vp, origlblkno)) {
vp->v_maxra = bp->b_lblkno + bp->b_bcount / size;
vp->v_ralen >>= 1;
return 0;
} else if( vp->v_maxra > origlblkno) {
} else if( vp->v_maxra >= origlblkno) {
if ((vp->v_ralen + 1) < (MAXPHYS / size))
vp->v_ralen++;
if ( vp->v_maxra > (origlblkno + 2*vp->v_ralen))
if ( vp->v_maxra >= (origlblkno + vp->v_ralen))
return 0;
lblkno = vp->v_maxra;
}
bp = NULL;
} else {
@ -181,12 +185,17 @@ cluster_read(vp, filesize, lblkno, size, cred, bpp)
vp->v_ralen >>= 1;
alreadyincore = 1;
} else {
if (inmem(vp, rablkno))
if (inmem(vp, rablkno)) {
if( vp->v_maxra < rablkno)
vp->v_maxra = rablkno + 1;
continue;
}
if ((vp->v_ralen + 1) < MAXPHYS / size)
vp->v_ralen++;
}
break;
} else if( vp->v_maxra < rablkno) {
vp->v_maxra = rablkno + 1;
}
}
}
@ -203,8 +212,7 @@ cluster_read(vp, filesize, lblkno, size, cred, bpp)
if (num_ra > vp->v_ralen)
num_ra = vp->v_ralen;
if (num_ra &&
((cnt.v_free_count + cnt.v_cache_count) > cnt.v_free_min)) {
if (num_ra) {
rbp = cluster_rbuild(vp, filesize,
NULL, rablkno, blkno, size, num_ra, B_READ | B_ASYNC);
} else {
@ -225,7 +233,6 @@ cluster_read(vp, filesize, lblkno, size, cred, bpp)
vfs_busy_pages(bp, 0);
error = VOP_STRATEGY(bp);
vp->v_maxra = bp->b_lblkno + bp->b_bcount / size;
/* printf("r:(%d, %d)", bp->b_lblkno, bp->b_bcount / size); */
totreads++;
totreadblocks += bp->b_bcount / size;
curproc->p_stats->p_ru.ru_inblock++;
@ -235,14 +242,13 @@ cluster_read(vp, filesize, lblkno, size, cred, bpp)
* and if we have read-aheads, do them too
*/
if (rbp) {
vp->v_maxra = rbp->b_lblkno + rbp->b_bcount / size;
if (error || (rbp->b_flags & B_CACHE)) {
rbp->b_flags &= ~(B_ASYNC | B_READ);
brelse(rbp);
} else {
vfs_busy_pages(rbp, 0);
(void) VOP_STRATEGY(rbp);
vp->v_maxra = rbp->b_lblkno + rbp->b_bcount / size;
/* printf("ra:(%d, %d)", rbp->b_lblkno, rbp->b_bcount / size); */
totreads++;
totreadblocks += rbp->b_bcount / size;
curproc->p_stats->p_ru.ru_inblock++;
@ -321,11 +327,6 @@ cluster_rbuild(vp, filesize, bp, lbn, blkno, size, run, flags)
inc = btodb(size);
for (bn = blkno, i = 0; i <= run; ++i, bn += inc) {
if (i != 0) {
/*
if (inmem(vp, lbn + i)) {
break;
}
*/
tbp = getblk(vp, lbn + i, size, 0, 0);
if ((tbp->b_flags & B_CACHE) ||
(tbp->b_flags & B_VMIO) != (bp->b_flags & B_VMIO)) {
@ -346,7 +347,7 @@ cluster_rbuild(vp, filesize, bp, lbn, blkno, size, run, flags)
bp->b_bcount += size;
bp->b_bufsize += size;
}
pmap_qenter(bp->b_data, bp->b_pages, bp->b_npages);
pmap_qenter((vm_offset_t) bp->b_data, (vm_page_t *)bp->b_pages, bp->b_npages);
return (bp);
}
@ -372,7 +373,7 @@ cluster_callback(bp)
error = bp->b_error;
b_save = (struct cluster_save *) (bp->b_saveaddr);
pmap_qremove(bp->b_data, bp->b_npages);
pmap_qremove((vm_offset_t) bp->b_data, bp->b_npages);
/*
* Move memory from the large cluster buffer into the component
* buffers and mark IO as done on these.
@ -606,7 +607,7 @@ cluster_wbuild(vp, last_bp, size, start_lbn, len, lbn)
b_save->bs_children[i] = tbp;
}
b_save->bs_nchildren = i;
pmap_qenter(bp->b_data, bp->b_pages, bp->b_npages);
pmap_qenter((vm_offset_t) bp->b_data, (vm_page_t *) bp->b_pages, bp->b_npages);
bawrite(bp);
if (i < len) {

4
sys/kern/vfs_export.c
View File

@ -36,7 +36,7 @@
* SUCH DAMAGE.
*
* @(#)vfs_subr.c 8.13 (Berkeley) 4/18/94
* $Id: vfs_subr.c,v 1.14 1995/01/09 16:04:54 davidg Exp $
* $Id: vfs_subr.c,v 1.15 1995/01/10 07:32:36 davidg Exp $
*/
/*
@ -417,7 +417,7 @@ vwakeup(bp)
vp->v_numoutput--;
if (vp->v_numoutput < 0)
panic("vwakeup: neg numoutput");
if (vp->v_flag & VBWAIT) {
if ((vp->v_numoutput == 0) && (vp->v_flag & VBWAIT)) {
vp->v_flag &= ~VBWAIT;
wakeup((caddr_t) &vp->v_numoutput);
}

4
sys/kern/vfs_subr.c
View File

@ -36,7 +36,7 @@
* SUCH DAMAGE.
*
* @(#)vfs_subr.c 8.13 (Berkeley) 4/18/94
* $Id: vfs_subr.c,v 1.14 1995/01/09 16:04:54 davidg Exp $
* $Id: vfs_subr.c,v 1.15 1995/01/10 07:32:36 davidg Exp $
*/
/*
@ -417,7 +417,7 @@ vwakeup(bp)
vp->v_numoutput--;
if (vp->v_numoutput < 0)
panic("vwakeup: neg numoutput");
if (vp->v_flag & VBWAIT) {
if ((vp->v_numoutput == 0) && (vp->v_flag & VBWAIT)) {
vp->v_flag &= ~VBWAIT;
wakeup((caddr_t) &vp->v_numoutput);
}