diff options
| author | David S. Miller <davem@sunset.davemloft.net> | 2006-03-17 23:40:47 -0800 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2006-03-20 01:16:38 -0800 |
| commit | b52439c22c63dbbefd5395f2151c0ef4f667e949 (patch) | |
| tree | ff6671cab70dfaed00cf19367a6a71b1cda0cdf4 | |
| parent | 05f9ca83596c7801549a2b4eba469d51baf5480f (diff) | |
[SPARC64]: Don't kill the page allocator when growing a TSB.
Try only lightly on > 1 order allocations.
If a grow fails, we are under memory pressure, so do not try
to grow the TSB for this address space any more.
If a > 0 order TSB allocation fails on a new fork, retry using
a 0 order allocation.
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | arch/sparc64/mm/tsb.c | 43 |
1 files changed, 35 insertions, 8 deletions
diff --git a/arch/sparc64/mm/tsb.c b/arch/sparc64/mm/tsb.c index 7fbe1e0cd105..3eb8670282fd 100644 --- a/arch/sparc64/mm/tsb.c +++ b/arch/sparc64/mm/tsb.c @@ -216,7 +216,8 @@ static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_bytes) * * The TSB can be anywhere from 8K to 1MB in size, in increasing powers * of two. The TSB must be aligned to it's size, so f.e. a 512K TSB - * must be 512K aligned. + * must be 512K aligned. It also must be physically contiguous, so we + * cannot use vmalloc(). * * The idea here is to grow the TSB when the RSS of the process approaches * the number of entries that the current TSB can hold at once. Currently, @@ -228,6 +229,8 @@ void tsb_grow(struct mm_struct *mm, unsigned long rss) unsigned long size, old_size, flags; struct page *page; struct tsb *old_tsb, *new_tsb; + unsigned long order, new_rss_limit; + gfp_t gfp_flags; if (max_tsb_size > (PAGE_SIZE << MAX_ORDER)) max_tsb_size = (PAGE_SIZE << MAX_ORDER); @@ -240,9 +243,37 @@ void tsb_grow(struct mm_struct *mm, unsigned long rss) break; } - page = alloc_pages(GFP_KERNEL, get_order(size)); - if (unlikely(!page)) + if (size == max_tsb_size) + new_rss_limit = ~0UL; + else + new_rss_limit = ((size / sizeof(struct tsb)) * 3) / 4; + +retry_page_alloc: + order = get_order(size); + gfp_flags = GFP_KERNEL; + if (order > 1) + gfp_flags = __GFP_NOWARN | __GFP_NORETRY; + + page = alloc_pages(gfp_flags, order); + if (unlikely(!page)) { + /* Not being able to fork due to a high-order TSB + * allocation failure is very bad behavior. Just back + * down to a 0-order allocation and force no TSB + * growing for this address space. + */ + if (mm->context.tsb == NULL && order > 0) { + size = PAGE_SIZE; + new_rss_limit = ~0UL; + goto retry_page_alloc; + } + + /* If we failed on a TSB grow, we are under serious + * memory pressure so don't try to grow any more. + */ + if (mm->context.tsb != NULL) + mm->context.tsb_rss_limit = ~0UL; return; + } /* Mark all tags as invalid. */ new_tsb = page_address(page); @@ -286,11 +317,7 @@ void tsb_grow(struct mm_struct *mm, unsigned long rss) return; } - if (size == max_tsb_size) - mm->context.tsb_rss_limit = ~0UL; - else - mm->context.tsb_rss_limit = - ((size / sizeof(struct tsb)) * 3) / 4; + mm->context.tsb_rss_limit = new_rss_limit; if (old_tsb) { extern void copy_tsb(unsigned long old_tsb_base, |