The patch titled
Subject: mm: honor PF_MEMALLOC_PIN for all movable pages
has been added to the -mm tree. Its filename is
mm-honor-pf_memalloc_pin-for-all-movable-pages.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-honor-pf_memalloc_pin-for-all-movable-pages.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-honor-pf_memalloc_pin-for-all-movable-pages.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
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------------------------------------------------------
From: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Subject: mm: honor PF_MEMALLOC_PIN for all movable pages
PF_MEMALLOC_PIN is only honored for CMA pages, extend this flag to work
for any allocations from ZONE_MOVABLE by removing __GFP_MOVABLE from
gfp_mask when this flag is passed in the current context.
Add is_pinnable_page() to return true if page is in a pinnable page. A
pinnable page is not in ZONE_MOVABLE and not of MIGRATE_CMA type.
Link: https://lkml.kernel.org/r/20210201153827.444374-8-pasha.tatashin@xxxxxxxxxx
Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
Cc: James Morris <jmorris@xxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Sasha Levin <sashal@xxxxxxxxxx>
Cc: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Cc: Tyler Hicks <tyhicks@xxxxxxxxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/mm.h | 11 +++++++++++
include/linux/sched/mm.h | 6 +++++-
mm/hugetlb.c | 2 +-
mm/page_alloc.c | 20 +++++++++-----------
4 files changed, 26 insertions(+), 13 deletions(-)
--- a/include/linux/mm.h~mm-honor-pf_memalloc_pin-for-all-movable-pages
+++ a/include/linux/mm.h
@@ -1116,6 +1116,17 @@ static inline bool is_zone_device_page(c
}
#endif
+static inline bool is_zone_movable_page(const struct page *page)
+{
+ return page_zonenum(page) == ZONE_MOVABLE;
+}
+
+/* MIGRATE_CMA and ZONE_MOVABLE do not allow pin pages */
+static inline bool is_pinnable_page(struct page *page)
+{
+ return !is_zone_movable_page(page) && !is_migrate_cma_page(page);
+}
+
#ifdef CONFIG_DEV_PAGEMAP_OPS
void free_devmap_managed_page(struct page *page);
DECLARE_STATIC_KEY_FALSE(devmap_managed_key);
--- a/include/linux/sched/mm.h~mm-honor-pf_memalloc_pin-for-all-movable-pages
+++ a/include/linux/sched/mm.h
@@ -150,12 +150,13 @@ static inline bool in_vfork(struct task_
* Applies per-task gfp context to the given allocation flags.
* PF_MEMALLOC_NOIO implies GFP_NOIO
* PF_MEMALLOC_NOFS implies GFP_NOFS
+ * PF_MEMALLOC_PIN implies !GFP_MOVABLE
*/
static inline gfp_t current_gfp_context(gfp_t flags)
{
unsigned int pflags = READ_ONCE(current->flags);
- if (unlikely(pflags & (PF_MEMALLOC_NOIO | PF_MEMALLOC_NOFS))) {
+ if (unlikely(pflags & (PF_MEMALLOC_NOIO | PF_MEMALLOC_NOFS | PF_MEMALLOC_PIN))) {
/*
* NOIO implies both NOIO and NOFS and it is a weaker context
* so always make sure it makes precedence
@@ -164,6 +165,9 @@ static inline gfp_t current_gfp_context(
flags &= ~(__GFP_IO | __GFP_FS);
else if (pflags & PF_MEMALLOC_NOFS)
flags &= ~__GFP_FS;
+
+ if (pflags & PF_MEMALLOC_PIN)
+ flags &= ~__GFP_MOVABLE;
}
return flags;
}
--- a/mm/hugetlb.c~mm-honor-pf_memalloc_pin-for-all-movable-pages
+++ a/mm/hugetlb.c
@@ -1052,7 +1052,7 @@ static struct page *dequeue_huge_page_no
bool pin = !!(current->flags & PF_MEMALLOC_PIN);
list_for_each_entry(page, &h->hugepage_freelists[nid], lru) {
- if (pin && is_migrate_cma_page(page))
+ if (pin && !is_pinnable_page(page))
continue;
if (PageHWPoison(page))
--- a/mm/page_alloc.c~mm-honor-pf_memalloc_pin-for-all-movable-pages
+++ a/mm/page_alloc.c
@@ -3807,16 +3807,13 @@ alloc_flags_nofragment(struct zone *zone
return alloc_flags;
}
-static inline unsigned int current_alloc_flags(gfp_t gfp_mask,
- unsigned int alloc_flags)
+/* Must be called after current_gfp_context() which can change gfp_mask */
+static inline unsigned int gfp_to_alloc_flags_cma(gfp_t gfp_mask,
+ unsigned int alloc_flags)
{
#ifdef CONFIG_CMA
- unsigned int pflags = current->flags;
-
- if (!(pflags & PF_MEMALLOC_PIN) &&
- gfp_migratetype(gfp_mask) == MIGRATE_MOVABLE)
+ if (gfp_migratetype(gfp_mask) == MIGRATE_MOVABLE)
alloc_flags |= ALLOC_CMA;
-
#endif
return alloc_flags;
}
@@ -4472,7 +4469,7 @@ gfp_to_alloc_flags(gfp_t gfp_mask)
} else if (unlikely(rt_task(current)) && !in_interrupt())
alloc_flags |= ALLOC_HARDER;
- alloc_flags = current_alloc_flags(gfp_mask, alloc_flags);
+ alloc_flags = gfp_to_alloc_flags_cma(gfp_mask, alloc_flags);
return alloc_flags;
}
@@ -4774,7 +4771,7 @@ retry:
reserve_flags = __gfp_pfmemalloc_flags(gfp_mask);
if (reserve_flags)
- alloc_flags = current_alloc_flags(gfp_mask, reserve_flags);
+ alloc_flags = gfp_to_alloc_flags_cma(gfp_mask, reserve_flags);
/*
* Reset the nodemask and zonelist iterators if memory policies can be
@@ -4943,7 +4940,7 @@ static inline bool prepare_alloc_pages(g
if (should_fail_alloc_page(gfp_mask, order))
return false;
- *alloc_flags = current_alloc_flags(gfp_mask, *alloc_flags);
+ *alloc_flags = gfp_to_alloc_flags_cma(gfp_mask, *alloc_flags);
/* Dirty zone balancing only done in the fast path */
ac->spread_dirty_pages = (gfp_mask & __GFP_WRITE);
@@ -4985,7 +4982,8 @@ __alloc_pages_nodemask(gfp_t gfp_mask, u
* Apply scoped allocation constraints. This is mainly about GFP_NOFS
* resp. GFP_NOIO which has to be inherited for all allocation requests
* from a particular context which has been marked by
- * memalloc_no{fs,io}_{save,restore}.
+ * memalloc_no{fs,io}_{save,restore}. And PF_MEMALLOC_PIN which ensures
+ * movable zones are not used during allocation.
*/
gfp_mask = current_gfp_context(gfp_mask);
alloc_mask = gfp_mask;
_
Patches currently in -mm which might be from pasha.tatashin@xxxxxxxxxx are
mm-gup-dont-pin-migrated-cma-pages-in-movable-zone.patch
mm-gup-check-every-subpage-of-a-compound-page-during-isolation.patch
mm-gup-return-an-error-on-migration-failure.patch
mm-gup-check-for-isolation-errors.patch
mm-cma-rename-pf_memalloc_nocma-to-pf_memalloc_pin.patch
mm-apply-per-task-gfp-constraints-in-fast-path.patch
mm-honor-pf_memalloc_pin-for-all-movable-pages.patch
mm-gup-do-not-migrate-zero-page.patch
mm-gup-migrate-pinned-pages-out-of-movable-zone.patch
memory-hotplugrst-add-a-note-about-zone_movable-and-page-pinning.patch
mm-gup-change-index-type-to-long-as-it-counts-pages.patch
mm-gup-longterm-pin-migration-cleanup.patch
selftests-vm-gup_test-fix-test-flag.patch
selftests-vm-gup_test-test-faulting-in-kernel-and-verify-pinnable-pages.patch
