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| author | alc <alc@FreeBSD.org> | 2014-05-17 14:35:18 +0000 |
|---|---|---|
| committer | alc <alc@FreeBSD.org> | 2014-05-17 14:35:18 +0000 |
| commit | a7358720d694c5ffce1cae23cb86d31cce4ea56a (patch) | |
| tree | 53dc2f6c2c16fb049aabfee37acceb2afaa4d909 /sys/vm/vm_map.c | |
| parent | ad5edf36f150331652638cd8026eb8e4424fff12 (diff) | |
| download | FreeBSD-src-a7358720d694c5ffce1cae23cb86d31cce4ea56a.zip FreeBSD-src-a7358720d694c5ffce1cae23cb86d31cce4ea56a.tar.gz | |
MFC r265850
About 9% of the pmap_protect() calls being performed by
vm_map_copy_entry() are unnecessary.
Eliminate the unnecessary calls.
Diffstat (limited to 'sys/vm/vm_map.c')
| -rw-r--r-- | sys/vm/vm_map.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c index cc94718..cd070df 100644 --- a/sys/vm/vm_map.c +++ b/sys/vm/vm_map.c @@ -3023,7 +3023,8 @@ vm_map_copy_entry( * If the source entry is marked needs_copy, it is already * write-protected. */ - if ((src_entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0) { + if ((src_entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0 && + (src_entry->protection & VM_PROT_WRITE) != 0) { pmap_protect(src_map->pmap, src_entry->start, src_entry->end, |
