The patch titled
Subject: mm, page_alloc: drop should_suppress_show_mem
has been added to the -mm tree. Its filename is
mm-page_alloc-drop-should_suppress_show_mem.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-page_alloc-drop-should_suppress_show_mem.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-page_alloc-drop-should_suppress_show_mem.patch
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------------------------------------------------------
From: Michal Hocko <mhocko@xxxxxxxx>
Subject: mm, page_alloc: drop should_suppress_show_mem
should_suppress_show_mem() was introduced to reduce the overhead of
show_mem on large NUMA systems. Things have changed since then though.
Namely c78e93630d15 ("mm: do not walk all of system memory during
show_mem") has reduced the overhead considerably.
Moreover warn_alloc_show_mem clears SHOW_MEM_FILTER_NODES when called from
the IRQ context already so we are not printing per node stats.
Remove should_suppress_show_mem because we are losing potentially
interesting information about allocation failures. We have seen a bug
report where system gets unresponsive under memory pressure and there is
only
kernel: [2032243.696888] qlge 0000:8b:00.1 ql1: Could not get a page chunk, i=8, clean_idx =200 .
kernel: [2032243.710725] swapper/7: page allocation failure: order:1, mode:0x1084120(GFP_ATOMIC|__GFP_COLD|__GFP_COMP)
without an additional information for debugging. It would be great to see
the state of the page allocator at the moment.
Link: http://lkml.kernel.org/r/20180907114334.7088-1-mhocko@xxxxxxxxxx
Signed-off-by: Michal Hocko <mhocko@xxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page_alloc.c | 16 +---------------
1 file changed, 1 insertion(+), 15 deletions(-)
--- a/mm/page_alloc.c~mm-page_alloc-drop-should_suppress_show_mem
+++ a/mm/page_alloc.c
@@ -3367,26 +3367,12 @@ try_this_zone:
return NULL;
}
-/*
- * Large machines with many possible nodes should not always dump per-node
- * meminfo in irq context.
- */
-static inline bool should_suppress_show_mem(void)
-{
- bool ret = false;
-
-#if NODES_SHIFT > 8
- ret = in_interrupt();
-#endif
- return ret;
-}
-
static void warn_alloc_show_mem(gfp_t gfp_mask, nodemask_t *nodemask)
{
unsigned int filter = SHOW_MEM_FILTER_NODES;
static DEFINE_RATELIMIT_STATE(show_mem_rs, HZ, 1);
- if (should_suppress_show_mem() || !__ratelimit(&show_mem_rs))
+ if (!__ratelimit(&show_mem_rs))
return;
/*
_
Patches currently in -mm which might be from mhocko@xxxxxxxx are
mmpage_alloc-pf_wq_worker-threads-must-sleep-at-should_reclaim_retry.patch
xen-gntdev-fix-up-blockable-calls-to-mn_invl_range_start.patch
mm-mmu_notifier-be-explicit-about-range-invalition-non-blocking-mode.patch
revert-mm-mmu_notifier-annotate-mmu-notifiers-with-blockable-invalidate-callbacks.patch
mm-page_alloc-drop-should_suppress_show_mem.patch
