Date: Sun, 29 Nov 2015 14:44:41 +0000 (UTC) From: Konstantin Belousov <kib@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-10@freebsd.org Subject: svn commit: r291454 - stable/10/sys/vm Message-ID: <201511291444.tATEifoa017199@repo.freebsd.org>
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Author: kib Date: Sun Nov 29 14:44:40 2015 New Revision: 291454 URL: https://svnweb.freebsd.org/changeset/base/291454 Log: MFC r289895: Reduce the amount of calls to VOP_BMAP() made from the local vnode pager. MFC r291157, r291158: Include the pages before/after the requested page, that fit into the reqblock, into the calculation of the size of run of pages. Tested by: pho Modified: stable/10/sys/vm/vnode_pager.c Directory Properties: stable/10/ (props changed) Modified: stable/10/sys/vm/vnode_pager.c ============================================================================== --- stable/10/sys/vm/vnode_pager.c Sun Nov 29 14:26:59 2015 (r291453) +++ stable/10/sys/vm/vnode_pager.c Sun Nov 29 14:44:40 2015 (r291454) @@ -696,26 +696,22 @@ vnode_pager_generic_getpages(vp, m, byte int reqpage; { vm_object_t object; - vm_offset_t kva; - off_t foff, tfoff, nextoff; - int i, j, size, bsize, first; - daddr_t firstaddr, reqblock; struct bufobj *bo; - int runpg; - int runend; struct buf *bp; struct mount *mp; - int count; - int error; - - object = vp->v_object; - count = bytecount / PAGE_SIZE; + vm_offset_t kva; + daddr_t firstaddr, reqblock; + off_t foff, nextoff, tfoff, pib; + int pbefore, pafter, i, size, bsize, first, last; + int count, error, before, after, secmask; KASSERT(vp->v_type != VCHR && vp->v_type != VBLK, ("vnode_pager_generic_getpages does not support devices")); if (vp->v_iflag & VI_DOOMED) - return VM_PAGER_BAD; + return (VM_PAGER_BAD); + object = vp->v_object; + count = bytecount / PAGE_SIZE; bsize = vp->v_mount->mnt_stat.f_iosize; /* get the UNDERLYING device for the file with VOP_BMAP() */ @@ -729,7 +725,8 @@ vnode_pager_generic_getpages(vp, m, byte /* * if we can't bmap, use old VOP code */ - error = VOP_BMAP(vp, foff / bsize, &bo, &reqblock, NULL, NULL); + error = VOP_BMAP(vp, IDX_TO_OFF(m[reqpage]->pindex) / bsize, &bo, + &reqblock, &after, &before); if (error == EOPNOTSUPP) { VM_OBJECT_WLOCK(object); @@ -772,7 +769,7 @@ vnode_pager_generic_getpages(vp, m, byte VM_OBJECT_WUNLOCK(object); PCPU_INC(cnt.v_vnodein); PCPU_INC(cnt.v_vnodepgsin); - return vnode_pager_input_smlfs(object, m[reqpage]); + return (vnode_pager_input_smlfs(object, m[reqpage])); } /* @@ -807,79 +804,40 @@ vnode_pager_generic_getpages(vp, m, byte m[reqpage]->valid = 0; VM_OBJECT_WUNLOCK(object); - /* - * here on direct device I/O - */ - firstaddr = -1; - - /* - * calculate the run that includes the required page - */ - for (first = 0, i = 0; i < count; i = runend) { - if (vnode_pager_addr(vp, IDX_TO_OFF(m[i]->pindex), &firstaddr, - &runpg) != 0) { - VM_OBJECT_WLOCK(object); - for (; i < count; i++) - if (i != reqpage) { - vm_page_lock(m[i]); - vm_page_free(m[i]); - vm_page_unlock(m[i]); - } - VM_OBJECT_WUNLOCK(object); - return (VM_PAGER_ERROR); - } - if (firstaddr == -1) { - VM_OBJECT_WLOCK(object); - if (i == reqpage && foff < object->un_pager.vnp.vnp_size) { - panic("vnode_pager_getpages: unexpected missing page: firstaddr: %jd, foff: 0x%jx%08jx, vnp_size: 0x%jx%08jx", - (intmax_t)firstaddr, (uintmax_t)(foff >> 32), - (uintmax_t)foff, - (uintmax_t) - (object->un_pager.vnp.vnp_size >> 32), - (uintmax_t)object->un_pager.vnp.vnp_size); - } + pib = IDX_TO_OFF(m[reqpage]->pindex) % bsize; + pbefore = ((daddr_t)before * bsize + pib) / PAGE_SIZE; + pafter = ((daddr_t)(after + 1) * bsize - pib) / PAGE_SIZE - 1; + first = reqpage < pbefore ? 0 : reqpage - pbefore; + last = reqpage + pafter >= count ? count - 1 : reqpage + pafter; + if (first > 0 || last + 1 < count) { + VM_OBJECT_WLOCK(object); + for (i = 0; i < first; i++) { vm_page_lock(m[i]); vm_page_free(m[i]); vm_page_unlock(m[i]); - VM_OBJECT_WUNLOCK(object); - runend = i + 1; - first = runend; - continue; } - runend = i + runpg; - if (runend <= reqpage) { - VM_OBJECT_WLOCK(object); - for (j = i; j < runend; j++) { - vm_page_lock(m[j]); - vm_page_free(m[j]); - vm_page_unlock(m[j]); - } - VM_OBJECT_WUNLOCK(object); - } else { - if (runpg < (count - first)) { - VM_OBJECT_WLOCK(object); - for (i = first + runpg; i < count; i++) { - vm_page_lock(m[i]); - vm_page_free(m[i]); - vm_page_unlock(m[i]); - } - VM_OBJECT_WUNLOCK(object); - count = first + runpg; - } - break; + for (i = last + 1; i < count; i++) { + vm_page_lock(m[i]); + vm_page_free(m[i]); + vm_page_unlock(m[i]); } - first = runend; + VM_OBJECT_WUNLOCK(object); } /* - * the first and last page have been calculated now, move input pages - * to be zero based... + * here on direct device I/O */ - if (first != 0) { - m += first; - count -= first; - reqpage -= first; - } + firstaddr = reqblock; + firstaddr += pib / DEV_BSIZE; + firstaddr -= IDX_TO_OFF(reqpage - first) / DEV_BSIZE; + + /* + * The first and last page have been calculated now, move + * input pages to be zero based, and adjust the count. + */ + m += first; + reqpage -= first; + count = last - first + 1; /* * calculate the file virtual address for the transfer @@ -898,13 +856,11 @@ vnode_pager_generic_getpages(vp, m, byte /* * round up physical size for real devices. */ - if (1) { - int secmask = bo->bo_bsize - 1; - KASSERT(secmask < PAGE_SIZE && secmask > 0, - ("vnode_pager_generic_getpages: sector size %d too large", - secmask + 1)); - size = (size + secmask) & ~secmask; - } + secmask = bo->bo_bsize - 1; + KASSERT(secmask < PAGE_SIZE && secmask > 0, + ("vnode_pager_generic_getpages: sector size %d too large", + secmask + 1)); + size = (size + secmask) & ~secmask; bp = getpbuf(&vnode_pbuf_freecnt); kva = (vm_offset_t)bp->b_data; @@ -1040,7 +996,7 @@ vnode_pager_putpages(vm_object_t object, /* * Force synchronous operation if we are extremely low on memory * to prevent a low-memory deadlock. VOP operations often need to - * allocate more memory to initiate the I/O ( i.e. do a BMAP + * allocate more memory to initiate the I/O ( i.e. do a BMAP * operation ). The swapper handles the case by limiting the amount * of asynchronous I/O, but that sort of solution doesn't scale well * for the vnode pager without a lot of work.
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