The patch titled
Subject: mm: introduce __GFP_MEMALLOC to allow access to emergency reserves
has been added to the -mm tree. Its filename is
mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves.patch
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*** 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: Mel Gorman <mgorman@xxxxxxx>
Subject: mm: introduce __GFP_MEMALLOC to allow access to emergency reserves
__GFP_MEMALLOC will allow the allocation to disregard the watermarks, much
like PF_MEMALLOC. It allows one to pass along the memalloc state in
object related allocation flags as opposed to task related flags, such as
sk->sk_allocation. This removes the need for ALLOC_PFMEMALLOC as callers
using __GFP_MEMALLOC can get the ALLOC_NO_WATERMARK flag which is now
enough to identify allocations related to page reclaim.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Signed-off-by: Mel Gorman <mgorman@xxxxxxx>
Cc: David Miller <davem@xxxxxxxxxxxxx>
Cc: Neil Brown <neilb@xxxxxxx>
Cc: Mike Christie <michaelc@xxxxxxxxxxx>
Cc: Eric B Munson <emunson@xxxxxxxxx>
Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Cc: Sebastian Andrzej Siewior <sebastian@xxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/gfp.h | 10 ++++++++--
include/linux/mm_types.h | 2 +-
include/trace/events/gfpflags.h | 1 +
mm/page_alloc.c | 22 ++++++++++------------
mm/slab.c | 2 +-
5 files changed, 21 insertions(+), 16 deletions(-)
diff -puN include/linux/gfp.h~mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves include/linux/gfp.h
--- a/include/linux/gfp.h~mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves
+++ a/include/linux/gfp.h
@@ -23,6 +23,7 @@ struct vm_area_struct;
#define ___GFP_REPEAT 0x400u
#define ___GFP_NOFAIL 0x800u
#define ___GFP_NORETRY 0x1000u
+#define ___GFP_MEMALLOC 0x2000u
#define ___GFP_COMP 0x4000u
#define ___GFP_ZERO 0x8000u
#define ___GFP_NOMEMALLOC 0x10000u
@@ -76,9 +77,14 @@ struct vm_area_struct;
#define __GFP_REPEAT ((__force gfp_t)___GFP_REPEAT) /* See above */
#define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL) /* See above */
#define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY) /* See above */
+#define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC)/* Allow access to emergency reserves */
#define __GFP_COMP ((__force gfp_t)___GFP_COMP) /* Add compound page metadata */
#define __GFP_ZERO ((__force gfp_t)___GFP_ZERO) /* Return zeroed page on success */
-#define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC) /* Don't use emergency reserves */
+#define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC) /* Don't use emergency reserves.
+ * This takes precedence over the
+ * __GFP_MEMALLOC flag if both are
+ * set
+ */
#define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL) /* Enforce hardwall cpuset memory allocs */
#define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE)/* No fallback, no policies */
#define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE) /* Page is reclaimable */
@@ -129,7 +135,7 @@ struct vm_area_struct;
/* Control page allocator reclaim behavior */
#define GFP_RECLAIM_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS|\
__GFP_NOWARN|__GFP_REPEAT|__GFP_NOFAIL|\
- __GFP_NORETRY|__GFP_NOMEMALLOC)
+ __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC)
/* Control slab gfp mask during early boot */
#define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_WAIT|__GFP_IO|__GFP_FS))
diff -puN include/linux/mm_types.h~mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves include/linux/mm_types.h
--- a/include/linux/mm_types.h~mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves
+++ a/include/linux/mm_types.h
@@ -55,7 +55,7 @@ struct page {
pgoff_t index; /* Our offset within mapping. */
void *freelist; /* slub/slob first free object */
bool pfmemalloc; /* If set by the page allocator,
- * ALLOC_PFMEMALLOC was set
+ * ALLOC_NO_WATERMARKS was set
* and the low watermark was not
* met implying that the system
* is under some pressure. The
diff -puN include/trace/events/gfpflags.h~mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves include/trace/events/gfpflags.h
--- a/include/trace/events/gfpflags.h~mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves
+++ a/include/trace/events/gfpflags.h
@@ -30,6 +30,7 @@
{(unsigned long)__GFP_COMP, "GFP_COMP"}, \
{(unsigned long)__GFP_ZERO, "GFP_ZERO"}, \
{(unsigned long)__GFP_NOMEMALLOC, "GFP_NOMEMALLOC"}, \
+ {(unsigned long)__GFP_MEMALLOC, "GFP_MEMALLOC"}, \
{(unsigned long)__GFP_HARDWALL, "GFP_HARDWALL"}, \
{(unsigned long)__GFP_THISNODE, "GFP_THISNODE"}, \
{(unsigned long)__GFP_RECLAIMABLE, "GFP_RECLAIMABLE"}, \
diff -puN mm/page_alloc.c~mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves mm/page_alloc.c
--- a/mm/page_alloc.c~mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves
+++ a/mm/page_alloc.c
@@ -1512,7 +1512,6 @@ failed:
#define ALLOC_HARDER 0x10 /* try to alloc harder */
#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
#define ALLOC_CPUSET 0x40 /* check for correct cpuset */
-#define ALLOC_PFMEMALLOC 0x80 /* Caller has PF_MEMALLOC set */
#ifdef CONFIG_FAIL_PAGE_ALLOC
@@ -2293,11 +2292,10 @@ gfp_to_alloc_flags(gfp_t gfp_mask)
} else if (unlikely(rt_task(current)) && !in_interrupt())
alloc_flags |= ALLOC_HARDER;
- if ((current->flags & PF_MEMALLOC) ||
- unlikely(test_thread_flag(TIF_MEMDIE))) {
- alloc_flags |= ALLOC_PFMEMALLOC;
-
- if (likely(!(gfp_mask & __GFP_NOMEMALLOC)) && !in_interrupt())
+ if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) {
+ if (gfp_mask & __GFP_MEMALLOC)
+ alloc_flags |= ALLOC_NO_WATERMARKS;
+ else if (likely(!(gfp_mask & __GFP_NOMEMALLOC)) && !in_interrupt())
alloc_flags |= ALLOC_NO_WATERMARKS;
}
@@ -2306,7 +2304,7 @@ gfp_to_alloc_flags(gfp_t gfp_mask)
bool gfp_pfmemalloc_allowed(gfp_t gfp_mask)
{
- return !!(gfp_to_alloc_flags(gfp_mask) & ALLOC_PFMEMALLOC);
+ return !!(gfp_to_alloc_flags(gfp_mask) & ALLOC_NO_WATERMARKS);
}
static inline struct page *
@@ -2497,12 +2495,12 @@ nopage:
return page;
got_pg:
/*
- * page->pfmemalloc is set when the caller had PFMEMALLOC set or is
- * been OOM killed. The expectation is that the caller is taking
- * steps that will free more memory. The caller should avoid the
- * page being used for !PFMEMALLOC purposes.
+ * page->pfmemalloc is set when the caller had PFMEMALLOC set, is
+ * been OOM killed or specified __GFP_MEMALLOC. The expectation is
+ * that the caller is taking steps that will free more memory. The
+ * caller should avoid the page being used for !PFMEMALLOC purposes.
*/
- page->pfmemalloc = !!(alloc_flags & ALLOC_PFMEMALLOC);
+ page->pfmemalloc = !!(alloc_flags & ALLOC_NO_WATERMARKS);
if (kmemcheck_enabled)
kmemcheck_pagealloc_alloc(page, order, gfp_mask);
diff -puN mm/slab.c~mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves mm/slab.c
--- a/mm/slab.c~mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves
+++ a/mm/slab.c
@@ -1883,7 +1883,7 @@ static void *kmem_getpages(struct kmem_c
return NULL;
}
- /* Record if ALLOC_PFMEMALLOC was set when allocating the slab */
+ /* Record if ALLOC_NO_WATERMARKS was set when allocating the slab */
if (unlikely(page->pfmemalloc))
pfmemalloc_active = true;
_
Subject: Subject: mm: introduce __GFP_MEMALLOC to allow access to emergency reserves
Patches currently in -mm which might be from mgorman@xxxxxxx are
origin.patch
linux-next.patch
memcg-prevent-oom-with-too-many-dirty-pages.patch
memcg-prevent-oom-with-too-many-dirty-pages-fix.patch
mm-do-not-use-page_count-without-a-page-pin.patch
mm-clean-up-__count_immobile_pages.patch
mm-hotplug-correctly-setup-fallback-zonelists-when-creating-new-pgdat.patch
mm-hotplug-correctly-add-new-zone-to-all-other-nodes-zone-lists.patch
mm-hotplug-free-zone-pageset-when-a-zone-becomes-empty.patch
mm-hotplug-mark-memory-hotplug-code-in-page_allocc-as-__meminit.patch
mm-factor-out-memory-isolate-functions.patch
mm-bug-fix-free-page-check-in-zone_watermark_ok.patch
memory-hotplug-fix-kswapd-looping-forever-problem.patch
memory-hotplug-fix-kswapd-looping-forever-problem-fix.patch
mm-slb-add-knowledge-of-pfmemalloc-reserve-pages.patch
mm-slub-optimise-the-slub-fast-path-to-avoid-pfmemalloc-checks.patch
mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves.patch
mm-allow-pf_memalloc-from-softirq-context.patch
mm-only-set-page-pfmemalloc-when-alloc_no_watermarks-was-used.patch
mm-ignore-mempolicies-when-using-alloc_no_watermark.patch
net-introduce-sk_gfp_atomic-to-allow-addition-of-gfp-flags-depending-on-the-individual-socket.patch
netvm-allow-the-use-of-__gfp_memalloc-by-specific-sockets.patch
netvm-allow-skb-allocation-to-use-pfmemalloc-reserves.patch
netvm-propagate-page-pfmemalloc-to-skb.patch
netvm-propagate-page-pfmemalloc-from-skb_alloc_page-to-skb.patch
netvm-set-pf_memalloc-as-appropriate-during-skb-processing.patch
mm-micro-optimise-slab-to-avoid-a-function-call.patch
nbd-set-sock_memalloc-for-access-to-pfmemalloc-reserves.patch
mm-throttle-direct-reclaimers-if-pf_memalloc-reserves-are-low-and-swap-is-backed-by-network-storage.patch
mm-account-for-the-number-of-times-direct-reclaimers-get-throttled.patch
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