Commit b52439c2 authored by David S. Miller's avatar David S. Miller

[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: default avatarDavid S. Miller <davem@davemloft.net>
parent 05f9ca83
......@@ -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,
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment