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author | dyson <dyson@FreeBSD.org> | 1996-07-27 03:24:10 +0000 |
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committer | dyson <dyson@FreeBSD.org> | 1996-07-27 03:24:10 +0000 |
commit | 293abd3564090ccf9196bbd4bc949163b91fce62 (patch) | |
tree | e65b39cf45164a5e0f930222b2d2e90148f2f518 /sys/vm/vm_mmap.c | |
parent | 5306d9c9d6bc06b09eb3c7ca700475faafbee5c1 (diff) | |
download | FreeBSD-src-293abd3564090ccf9196bbd4bc949163b91fce62.zip FreeBSD-src-293abd3564090ccf9196bbd4bc949163b91fce62.tar.gz |
This commit is meant to solve a couple of VM system problems or
performance issues.
1) The pmap module has had too many inlines, and so the
object file is simply bigger than it needs to be.
Some common code is also merged into subroutines.
2) Removal of some *evil* PHYS_TO_VM_PAGE macro calls.
Unfortunately, a few have needed to be added also.
The removal caused the need for more vm_page_lookups.
I added lookup hints to minimize the need for the
page table lookup operations.
3) Removal of some bogus performance improvements, that
mostly made the code more complex (tracking individual
page table page updates unnecessarily). Those improvements
actually hurt 386 processors perf (not that people who
worry about perf use 386 processors anymore :-)).
4) Changed pv queue manipulations/structures to be TAILQ's.
5) The pv queue code has had some performance problems since
day one. Some significant scalability issues are resolved
by threading the pv entries from the pmap AND the physical
address instead of just the physical address. This makes
certain pmap operations run much faster. This does
not affect most micro-benchmarks, but should help loaded system
performance *significantly*. DG helped and came up with most
of the solution for this one.
6) Most if not all pmap bit operations follow the pattern:
pmap_test_bit();
pmap_clear_bit();
That made for twice the necessary pv list traversal. The
pmap interface now supports only pmap_tc_bit type operations:
pmap_[test/clear]_modified, pmap_[test/clear]_referenced.
Additionally, the modified routine now takes a vm_page_t arg
instead of a phys address. This eliminates a PHYS_TO_VM_PAGE
operation.
7) Several rewrites of routines that contain redundant code to
use common routines, so that there is a greater likelihood of
keeping the cache footprint smaller.
Diffstat (limited to 'sys/vm/vm_mmap.c')
-rw-r--r-- | sys/vm/vm_mmap.c | 204 |
1 files changed, 177 insertions, 27 deletions
diff --git a/sys/vm/vm_mmap.c b/sys/vm/vm_mmap.c index 697baf6..ff0e79c 100644 --- a/sys/vm/vm_mmap.c +++ b/sys/vm/vm_mmap.c @@ -38,7 +38,7 @@ * from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$ * * @(#)vm_mmap.c 8.4 (Berkeley) 1/12/94 - * $Id: vm_mmap.c,v 1.43 1996/05/19 07:36:49 dyson Exp $ + * $Id: vm_mmap.c,v 1.44 1996/05/31 00:38:00 dyson Exp $ */ /* @@ -72,6 +72,7 @@ #include <vm/vm_extern.h> #include <vm/vm_kern.h> #include <vm/vm_page.h> +#include <vm/loadaout.h> #ifndef _SYS_SYSPROTO_H_ struct sbrk_args { @@ -689,10 +690,10 @@ mincore(p, uap, retval) if (m) { mincoreinfo = MINCORE_INCORE; if (m->dirty || - pmap_is_modified(VM_PAGE_TO_PHYS(m))) + pmap_tc_modified(m)) mincoreinfo |= MINCORE_MODIFIED_OTHER; if ((m->flags & PG_REFERENCED) || - pmap_is_referenced(VM_PAGE_TO_PHYS(m))) + pmap_tc_referenced(VM_PAGE_TO_PHYS(m))) mincoreinfo |= MINCORE_REFERENCED_OTHER; } } @@ -844,7 +845,7 @@ vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff) vm_ooffset_t foff; { boolean_t fitit; - vm_object_t object, object2; + vm_object_t object; struct vnode *vp = NULL; objtype_t type; int rv = KERN_SUCCESS; @@ -916,29 +917,13 @@ vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff) flags |= MAP_SHARED; } - object2 = NULL; docow = 0; if ((flags & (MAP_ANON|MAP_SHARED)) == 0) { - docow = MAP_COPY_ON_WRITE; - if (objsize < size) { - object2 = vm_object_allocate( OBJT_DEFAULT, - OFF_TO_IDX(size - (foff & ~PAGE_MASK))); - object2->backing_object = object; - object2->backing_object_offset = foff; - TAILQ_INSERT_TAIL(&object->shadow_head, - object2, shadow_list); - ++object->shadow_count; - } else { - docow |= MAP_COPY_NEEDED; - } + docow = MAP_COPY_ON_WRITE|MAP_COPY_NEEDED; } - if (object2) - rv = vm_map_find(map, object2, 0, addr, size, fitit, - prot, maxprot, docow); - else - rv = vm_map_find(map, object, foff, addr, size, fitit, - prot, maxprot, docow); + rv = vm_map_find(map, object, foff, addr, size, fitit, + prot, maxprot, docow); if (rv != KERN_SUCCESS) { @@ -947,10 +932,7 @@ vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff) * object if it's an unnamed anonymous mapping * or named anonymous without other references. */ - if (object2) - vm_object_deallocate(object2); - else - vm_object_deallocate(object); + vm_object_deallocate(object); goto out; } @@ -985,3 +967,171 @@ out: return (EINVAL); } } + +#ifdef notyet +/* + * Efficient mapping of a .text+.data+.bss object + */ +int +vm_mapaout(map, baseaddr, vp, foff, textsize, datasize, bsssize, addr) + vm_map_t map; + vm_offset_t baseaddr; + struct vnode *vp; + vm_ooffset_t foff; + register vm_size_t textsize, datasize, bsssize; + vm_offset_t *addr; +{ + vm_object_t object; + int rv; + vm_pindex_t objpsize; + struct proc *p = curproc; + + vm_size_t totalsize; + vm_size_t textend; + struct vattr vat; + int error; + + textsize = round_page(textsize); + datasize = round_page(datasize); + bsssize = round_page(bsssize); + totalsize = textsize + datasize + bsssize; + + vm_map_lock(map); + /* + * If baseaddr == -1, then we need to search for space. Otherwise, + * we need to be loaded into a certain spot. + */ + if (baseaddr != (vm_offset_t) -1) { + if (vm_map_findspace(map, baseaddr, totalsize, addr)) { + goto outnomem; + } + + if(*addr != baseaddr) { + goto outnomem; + } + } else { + baseaddr = round_page(p->p_vmspace->vm_daddr + MAXDSIZ); + if (vm_map_findspace(map, baseaddr, totalsize, addr)) { + goto outnomem; + } + } + + if (foff & PAGE_MASK) { + vm_map_unlock(map); + return EINVAL; + } + + /* + * get the object size to allocate + */ + error = VOP_GETATTR(vp, &vat, p->p_ucred, p); + if (error) { + vm_map_unlock(map); + return error; + } + objpsize = OFF_TO_IDX(round_page(vat.va_size)); + + /* + * Alloc/reference the object + */ + object = vm_pager_allocate(OBJT_VNODE, vp, + objpsize, VM_PROT_ALL, foff); + if (object == NULL) { + goto outnomem; + } + + /* + * Insert .text into the map + */ + textend = *addr + textsize; + rv = vm_map_insert(map, object, foff, + *addr, textend, + VM_PROT_READ|VM_PROT_EXECUTE, VM_PROT_ALL, + MAP_COPY_ON_WRITE|MAP_COPY_NEEDED); + if (rv != KERN_SUCCESS) { + vm_object_deallocate(object); + goto out; + } + + /* + * Insert .data into the map, if there is any to map. + */ + if (datasize != 0) { + object->ref_count++; + rv = vm_map_insert(map, object, foff + textsize, + textend, textend + datasize, + VM_PROT_ALL, VM_PROT_ALL, + MAP_COPY_ON_WRITE|MAP_COPY_NEEDED); + if (rv != KERN_SUCCESS) { + --object->ref_count; + vm_map_delete(map, *addr, textend); + goto out; + } + } + + /* + * Preload the page tables + */ + pmap_object_init_pt(map->pmap, *addr, + object, (vm_pindex_t) OFF_TO_IDX(foff), + textsize + datasize, 1); + + /* + * Get the space for bss. + */ + if (bsssize != 0) { + rv = vm_map_insert(map, NULL, 0, + textend + datasize, + *addr + totalsize, + VM_PROT_ALL, VM_PROT_ALL, 0); + } + if (rv != KERN_SUCCESS) { + vm_map_delete(map, *addr, textend + datasize + bsssize); + } + +out: + vm_map_unlock(map); + switch (rv) { + case KERN_SUCCESS: + return 0; + case KERN_INVALID_ADDRESS: + case KERN_NO_SPACE: + return ENOMEM; + case KERN_PROTECTION_FAILURE: + return EACCES; + default: + return EINVAL; + } +outnomem: + vm_map_unlock(map); + return ENOMEM; +} + + +int +mapaout(struct proc *p, struct mapaout_args *uap, int *retval) +{ + + register struct filedesc *fdp = p->p_fd; + struct file *fp; + struct vnode *vp; + int rtval; + + if (((unsigned) uap->fd) >= fdp->fd_nfiles || + (fp = fdp->fd_ofiles[uap->fd]) == NULL) + return (EBADF); + if (fp->f_type != DTYPE_VNODE) + return (EINVAL); + + vp = (struct vnode *) fp->f_data; + if ((vp->v_type != VREG) && (vp->v_type != VCHR)) + return (EINVAL); + + rtval = vm_mapaout( &p->p_vmspace->vm_map, + uap->addr, vp, uap->offset, + uap->textsize, uap->datasize, uap->bsssize, + (vm_offset_t *)retval); + + return rtval; +} +#endif |