d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Staticize swap_pager_putpages()

Browse Source 
Eliminate a lot of checkes to make sure requests are not cross-device
which is unnecessary with the new layout.  We know a sequential request
cannot possibly be cross-device because there is a reserved page between
the devices.

Remove a couple of comments which no longer are relevant.
This commit is contained in:
Poul-Henning Kamp 2003-08-06 12:08:27 +00:00
parent 030b34923d
commit 751221fd32
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=118536
2 changed files with 4 additions and 36 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
sys/vm/swap_pager.c
View File

@ -220,6 +220,7 @@ static vm_object_t
vm_prot_t prot, vm_ooffset_t offset);
static void swap_pager_dealloc(vm_object_t object);
static int swap_pager_getpages(vm_object_t, vm_page_t *, int, int);
static void swap_pager_putpages(vm_object_t, vm_page_t *, int, boolean_t, int *);
static boolean_t
swap_pager_haspage(vm_object_t object, vm_pindex_t pindex, int *before, int *after);
static void swap_pager_init(void);
@ -243,7 +244,7 @@ struct pagerops swappagerops = {
* swap_*() routines are externally accessible. swp_*() routines are
* internal.
*/
static int dmmax, dmmax_mask;
static int dmmax;
static int nswap_lowat = 128; /* in pages, swap_pager_almost_full warn */
static int nswap_hiwat = 512; /* in pages, swap_pager_almost_full warn */
@ -351,7 +352,6 @@ swap_pager_init()
* Device Stripe, in PAGE_SIZE'd blocks
*/
dmmax = SWB_NPAGES * 2;
dmmax_mask = ~(dmmax - 1);
}
/*
@ -971,7 +971,6 @@ swap_pager_getpages(object, m, count, reqpage)
int i;
int j;
daddr_t blk;
vm_pindex_t lastpindex;
mreq = m[reqpage];
@ -981,8 +980,8 @@ swap_pager_getpages(object, m, count, reqpage)
/*
* Calculate range to retrieve. The pages have already been assigned
* their swapblks. We require a *contiguous* range that falls entirely
* within a single device stripe. If we do not supply it, bad things
* their swapblks. We require a *contiguous* range but we know it to
* not span devices. If we do not supply it, bad things
* happen. Note that blk, iblk & jblk can be SWAPBLK_NONE, but the
* loops are set up such that the case(s) are handled implicitly.
*
@ -998,8 +997,6 @@ swap_pager_getpages(object, m, count, reqpage)
iblk = swp_pager_meta_ctl(m[i]->object, m[i]->pindex, 0);
if (blk != iblk + (reqpage - i))
break;
if ((blk ^ iblk) & dmmax_mask)
break;
}
++i;
@ -1009,8 +1006,6 @@ swap_pager_getpages(object, m, count, reqpage)
jblk = swp_pager_meta_ctl(m[j]->object, m[j]->pindex, 0);
if (blk != jblk - (j - reqpage))
break;
if ((blk ^ jblk) & dmmax_mask)
break;
}
/*
@ -1085,7 +1080,6 @@ swap_pager_getpages(object, m, count, reqpage)
VM_OBJECT_LOCK(mreq->object);
vm_object_pip_add(mreq->object, bp->b_npages);
VM_OBJECT_UNLOCK(mreq->object);
lastpindex = m[j-1]->pindex;
/*
* perform the I/O. NOTE!!! bp cannot be considered valid after
@ -1272,17 +1266,6 @@ swap_pager_putpages(object, m, count, sync, rtvals)
continue;
}
/*
* The I/O we are constructing cannot cross a physical
* disk boundry in the swap stripe. Note: we are still
* at splvm().
*/
if ((blk ^ (blk + n)) & dmmax_mask) {
j = ((blk + dmmax) & dmmax_mask) - blk;
swp_pager_freeswapspace(blk + j, n - j);
n = j;
}
/*
* All I/O parameters have been satisfied, build the I/O
* request and assign the swap space.
@ -2159,15 +2142,6 @@ swapon(td, uap)
return (error);
}
/*
* Swfree(index) frees the index'th portion of the swap map.
* Each of the NSWAPDEV devices provides 1/NSWAPDEV'th of the swap
* space, which is laid out with blocks of dmmax pages circularly
* among the devices.
*
* The new swap code uses page-sized blocks. The old swap code used
* DEV_BSIZE'd chunks.
*/
int
swaponvp(td, vp, dev, nblks)
struct thread *td;

6
sys/vm/swap_pager.h
View File

@ -39,11 +39,6 @@
* $FreeBSD$
*/
/*
* Modifications to the block allocation data structure by John S. Dyson
* 18 Dec 93.
*/
#ifndef _VM_SWAP_PAGER_H_
#define _VM_SWAP_PAGER_H_ 1
@ -53,7 +48,6 @@ extern int swap_pager_full;
extern int swap_pager_avail;
struct swdevt;
void swap_pager_putpages(vm_object_t, vm_page_t *, int, boolean_t, int *);
void swap_pager_copy(vm_object_t, vm_object_t, vm_pindex_t, int);
void swap_pager_freespace(vm_object_t, vm_pindex_t, vm_size_t);
void swap_pager_swap_init(void);