diff options
| author | alc <alc@FreeBSD.org> | 2012-08-05 16:59:02 +0000 |
|---|---|---|
| committer | alc <alc@FreeBSD.org> | 2012-08-05 16:59:02 +0000 |
| commit | bc11d86648e5ccdc7ad2944f1272d0013325e922 (patch) | |
| tree | 27cea1a9e86ae9f70e31379a44f2266dc99ac49d /sys/amd64 | |
| parent | 7c93ab23a4ba04ce7f001aa304895edb49b287fd (diff) | |
| download | FreeBSD-src-bc11d86648e5ccdc7ad2944f1272d0013325e922.zip FreeBSD-src-bc11d86648e5ccdc7ad2944f1272d0013325e922.tar.gz | |
Shave off a few more cycles from the average execution time of pmap_enter()
by simplifying the control flow and reducing the live range of "om".
Diffstat (limited to 'sys/amd64')
| -rw-r--r-- | sys/amd64/amd64/pmap.c | 9 |
1 files changed, 2 insertions, 7 deletions
diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c index 3ae1230..1f22189 100644 --- a/sys/amd64/amd64/pmap.c +++ b/sys/amd64/amd64/pmap.c @@ -3468,7 +3468,7 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_prot_t access, vm_page_t m, newpte |= PG_G; newpte |= pmap_cache_bits(m->md.pat_mode, 0); - mpte = om = NULL; + mpte = NULL; lock = NULL; rw_rlock(&pvh_global_lock); @@ -3540,12 +3540,6 @@ retry: if (((origpte ^ newpte) & ~(PG_M | PG_A)) == 0) goto unchanged; goto validate; - } else { - /* - * Yes, fall through to validate the new mapping. - */ - if ((origpte & PG_MANAGED) != 0) - om = PHYS_TO_VM_PAGE(opa); } } else { /* @@ -3578,6 +3572,7 @@ validate: opa = origpte & PG_FRAME; if (opa != pa) { if ((origpte & PG_MANAGED) != 0) { + om = PHYS_TO_VM_PAGE(opa); if ((origpte & (PG_M | PG_RW)) == (PG_M | PG_RW)) vm_page_dirty(om); |
