diff options
| author | Hugh Dickins <hugh@veritas.com> | 2005-10-29 18:15:53 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-10-29 21:40:36 -0700 |
| commit | e040f218bb49a6965a5b77edce05fe47a62dda39 (patch) | |
| tree | e5547e04fa312f1b87db66e4ac2b6eed885ca276 /mm/memory.c | |
| parent | 09ad4bbc3a5c93316d7f4ffc0c310d9cbb28c2f0 (diff) | |
| download | lwn-e040f218bb49a6965a5b77edce05fe47a62dda39.tar.gz lwn-e040f218bb49a6965a5b77edce05fe47a62dda39.zip | |
[PATCH] mm: copy_pte_range progress fix
My latency breaking in copy_pte_range didn't work as intended: instead of
checking at regularish intervals, after the first interval it checked every
time around the loop, too impatient to be preempted. Fix that.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/mm/memory.c b/mm/memory.c index 1db40e935e55..222c13e46130 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -410,7 +410,7 @@ static int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, { pte_t *src_pte, *dst_pte; unsigned long vm_flags = vma->vm_flags; - int progress; + int progress = 0; again: dst_pte = pte_alloc_map(dst_mm, dst_pmd, addr); @@ -418,17 +418,19 @@ again: return -ENOMEM; src_pte = pte_offset_map_nested(src_pmd, addr); - progress = 0; spin_lock(&src_mm->page_table_lock); do { /* * We are holding two locks at this point - either of them * could generate latencies in another task on another CPU. */ - if (progress >= 32 && (need_resched() || - need_lockbreak(&src_mm->page_table_lock) || - need_lockbreak(&dst_mm->page_table_lock))) - break; + if (progress >= 32) { + progress = 0; + if (need_resched() || + need_lockbreak(&src_mm->page_table_lock) || + need_lockbreak(&dst_mm->page_table_lock)) + break; + } if (pte_none(*src_pte)) { progress++; continue; |