Attachment 188607 Details for Bug 223831 – swapoff to release multiple blocks at a time for 11-stable

[patch] swapoff to release multiple blocks at a time for 11-stable

vm_swap-multiblock-swapoff-11.diff (text/plain), 3.44 KB, created by ota on 2017-12-07 03:47:43 UTC

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Creator: ota

Created: 2017-12-07 03:47:43 UTC

Size: 3.44 KB

patch

obsolete

>Index: sys/vm/swap_pager.c
>===================================================================
>--- sys/vm/swap_pager.c	(revision 326483)
>+++ sys/vm/swap_pager.c	(working copy)
>@@ -1621,39 +1768,62 @@
>  *	We also attempt to swap in all other pages in the swap block.
>  *	However, we only guarantee that the one at the specified index is
>  *	paged in.
>- *
>- *	XXX - The code to page the whole block in doesn't work, so we
>- *	      revert to the one-by-one behavior for now.  Sigh.
>  */
>-static inline void
>-swp_pager_force_pagein(vm_object_t object, vm_pindex_t pindex)
>+static void
>+swp_pager_activate_vmpage(vm_object_t object, vm_page_t m)
> {
>-	vm_page_t m;
>-
>-	vm_object_pip_add(object, 1);
>-	m = vm_page_grab(object, pindex, VM_ALLOC_NORMAL);
>-	if (m->valid == VM_PAGE_BITS_ALL) {
>-		vm_object_pip_wakeup(object);
>-		vm_page_dirty(m);
>-		vm_page_lock(m);
>-		vm_page_activate(m);
>-		vm_page_unlock(m);
>-		vm_page_xunbusy(m);
>-		vm_pager_page_unswapped(m);
>-		return;
>-	}
>-
>-	if (swap_pager_getpages(object, &m, 1, NULL, NULL) != VM_PAGER_OK)
>-		panic("swap_pager_force_pagein: read from swap failed");/*XXX*/
> 	vm_object_pip_wakeup(object);
> 	vm_page_dirty(m);
> 	vm_page_lock(m);
>+	vm_page_activate(m);
>+	vm_page_unlock(m);
>+	vm_page_xunbusy(m);
>+	vm_pager_page_unswapped(m);
>+}
>+static void
>+swp_pager_launder_vmpage(vm_object_t object, vm_page_t m)
>+{
>+	vm_object_pip_wakeup(object);
>+	vm_page_dirty(m);
>+	vm_page_lock(m);
> 	vm_page_launder(m);
> 	vm_page_unlock(m);
> 	vm_page_xunbusy(m);
> 	vm_pager_page_unswapped(m);
> }
>+static int
>+swp_pager_force_pagein(vm_object_t object, vm_pindex_t pindex)
>+{
>+	vm_page_t m[SWB_NPAGES];
>+	int count, i, j, npages, rv;
> 
>+	rv = swap_pager_haspage(object, pindex, NULL, &npages);
>+	KASSERT(rv == 1, ("%s: missing page %p", __func__, m));
>+	npages += 1;
>+	i = vm_page_grab_pages(object, pindex, VM_ALLOC_NORMAL, m, npages);
>+	vm_object_pip_add(object, npages);
>+
>+	for (i = 0; i < npages;) {
>+		if (m[i]->valid == VM_PAGE_BITS_ALL) {
>+			swp_pager_activate_vmpage(object, m[i]);
>+			i++;
>+			continue;
>+		}
>+
>+		for (j = i + 1; j < npages; j++)
>+			if (m[j]->valid == VM_PAGE_BITS_ALL)
>+				break;
>+
>+		count = j - i;
>+		if (swap_pager_getpages(object, &m[i], count, NULL, NULL) != VM_PAGER_OK)
>+			panic("swap_pager_force_pagein: read from swap failed");/*XXX*/
>+		for (; i < j; i++) {
>+			swp_pager_launder_vmpage(object, m[i]);
>+		}
>+	}
>+	return npages;
>+}
>+
> /*
>  *	swap_pager_swapoff:
>  *
>@@ -1670,7 +1842,7 @@
> 	struct swblk *sb;
> 	vm_object_t object;
> 	vm_pindex_t pi;
>-	int i, retries;
>+	int freedpages, i, offset, retries;
> 
> 	sx_assert(&swdev_syscall_lock, SA_XLOCKED);
> 
>@@ -1700,15 +1872,28 @@
> 		if (object->type != OBJT_SWAP)
> 			goto next_obj;
> 
>+		freedpages = offset = 0;
> 		for (pi = 0; (sb = SWAP_PCTRIE_LOOKUP_GE(
> 		    &object->un_pager.swp.swp_blks, pi)) != NULL; ) {
> 			pi = sb->p + SWAP_META_PAGES;
>-			for (i = 0; i < SWAP_META_PAGES; i++) {
>+			if (freedpages > SWAP_META_PAGES) {
>+				freedpages -= SWAP_META_PAGES;
>+				continue;
>+			} else if (offset > 0) {
>+				i = freedpages;
>+				freedpages = 0;
>+			} else
>+				i = 0;
>+			for (; i < SWAP_META_PAGES; i++) {
> 				if (sb->d[i] == SWAPBLK_NONE)
> 					continue;
>-				if (swp_pager_isondev(sb->d[i], sp))
>-					swp_pager_force_pagein(object,
>+				if (swp_pager_isondev(sb->d[i], sp)) {
>+					freedpages = swp_pager_force_pagein(object,
> 					    sb->p + i);
>+					offset = min(freedpages, SWAP_META_PAGES - i);
>+					freedpages -= offset;
>+					i += ( offset - 1 );
>+				}
> 			}
> 		}
> next_obj:

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Attachments on bug 223831: 188225 | 188460 | 188607 | 188608