Subject: + mm-page_alloc-allow-__gfp_nofail-to-allocate-below-watermarks-after-reclaim.patch added to -mm tree To: rientjes@xxxxxxxxxx,mgorman@xxxxxxx,mhocko@xxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Mon, 09 Dec 2013 15:23:29 -0800 The patch titled Subject: mm, page_alloc: allow __GFP_NOFAIL to allocate below watermarks after reclaim has been added to the -mm tree. Its filename is mm-page_alloc-allow-__gfp_nofail-to-allocate-below-watermarks-after-reclaim.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-page_alloc-allow-__gfp_nofail-to-allocate-below-watermarks-after-reclaim.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-page_alloc-allow-__gfp_nofail-to-allocate-below-watermarks-after-reclaim.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: David Rientjes <rientjes@xxxxxxxxxx> Subject: mm, page_alloc: allow __GFP_NOFAIL to allocate below watermarks after reclaim If direct reclaim has failed to free memory, __GFP_NOFAIL allocations can potentially loop forever in the page allocator. In this case, it's better to give them the ability to access below watermarks so that they may allocate similar to the same privilege given to GFP_ATOMIC allocations. We're careful to ensure this is only done after direct reclaim has had the chance to free memory, however. Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_alloc.c | 5 +++++ 1 file changed, 5 insertions(+) diff -puN mm/page_alloc.c~mm-page_alloc-allow-__gfp_nofail-to-allocate-below-watermarks-after-reclaim mm/page_alloc.c --- a/mm/page_alloc.c~mm-page_alloc-allow-__gfp_nofail-to-allocate-below-watermarks-after-reclaim +++ a/mm/page_alloc.c @@ -2622,6 +2622,11 @@ rebalance: pages_reclaimed)) { /* Wait for some write requests to complete then retry */ wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50); + + /* Allocations that cannot fail must allocate from somewhere */ + if (gfp_mask & __GFP_NOFAIL) + alloc_flags |= ALLOC_HARDER; + goto rebalance; } else { /* _ Patches currently in -mm which might be from rientjes@xxxxxxxxxx are include-linux-hugetlbh-make-isolate_huge_page-an-inline.patch mm-memcg-do-not-declare-oom-from-__gfp_nofail-allocations.patch mm-memcg-fix-race-condition-between-memcg-teardown-and-swapin.patch mm-memcg-do-not-allow-task-about-to-oom-kill-to-bypass-the-limit.patch arch-x86-mm-sratc-skip-numa_no_node-while-parsing-slit.patch arch-x86-mm-sratc-skip-numa_no_node-while-parsing-slit-fix.patch mm-memcg-avoid-oom-notification-when-current-needs-access-to-memory-reserves.patch mm-mempolicy-remove-unneeded-functions-for-uma-configs.patch mm-show_mem-remove-show_mem_filter_page_count.patch introduce-for_each_thread-to-replace-the-buggy-while_each_thread.patch oom_kill-change-oom_killc-to-use-for_each_thread.patch oom_kill-has_intersects_mems_allowed-needs-rcu_read_lock.patch oom_kill-add-rcu_read_lock-into-find_lock_task_mm.patch mm-page_alloc-allow-__gfp_nofail-to-allocate-below-watermarks-after-reclaim.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html