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

arm64: Use page_to_pvh() when the vm_page_t is known

Browse Source 
When support for a sparse pv_table was added, the implementation of
pa_to_pvh() changed from a simple constant-time calculation to iterating
over the array vm_phys_segs[].  To mitigate this issue, an alternative
function, page_to_pvh(), was introduced that still runs in constant time
but requires the vm_page_t to be known.  However, three cases where the
vm_page_t is known were not converted to page_to_pvh().  This change
converts those three cases.

Reviewed by:	kib, markj
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D30832
This commit is contained in:
Alan Cox 2021-06-21 02:45:21 -05:00
parent bf7b542e02
commit 6f6a166eaf
1 changed files with 3 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
sys/arm64/arm64/pmap.c
View File

@ -3474,7 +3474,7 @@ pmap_pv_promote_l2(pmap_t pmap, vm_offset_t va, vm_paddr_t pa,
va = va & ~L2_OFFSET;
pv = pmap_pvh_remove(&m->md, pmap, va);
KASSERT(pv != NULL, ("pmap_pv_promote_l2: pv not found"));
pvh = pa_to_pvh(pa);
pvh = page_to_pvh(m);
TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
pvh->pv_gen++;
/* Free the remaining NPTEPG - 1 pv entries. */
@ -3896,7 +3896,7 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
if ((om->a.flags & PGA_WRITEABLE) != 0 &&
TAILQ_EMPTY(&om->md.pv_list) &&
((om->flags & PG_FICTITIOUS) != 0 ||
TAILQ_EMPTY(&pa_to_pvh(opa)->pv_list)))
TAILQ_EMPTY(&page_to_pvh(om)->pv_list)))
vm_page_aflag_clear(om, PGA_WRITEABLE);
} else {
KASSERT((orig_l3 & ATTR_AF) != 0,
@ -5000,7 +5000,7 @@ pmap_remove_pages(pmap_t pmap)
case 1:
pmap_resident_count_dec(pmap,
L2_SIZE / PAGE_SIZE);
pvh = pa_to_pvh(tpte & ~ATTR_MASK);
pvh = page_to_pvh(m);
TAILQ_REMOVE(&pvh->pv_list, pv,pv_next);
pvh->pv_gen++;
if (TAILQ_EMPTY(&pvh->pv_list)) {