remarkable-linux/include/linux/gfp.h
Johannes Weiner e97ca8e5b8 mm: fix GFP_THISNODE callers and clarify
GFP_THISNODE is for callers that implement their own clever fallback to
remote nodes.  It restricts the allocation to the specified node and
does not invoke reclaim, assuming that the caller will take care of it
when the fallback fails, e.g.  through a subsequent allocation request
without GFP_THISNODE set.

However, many current GFP_THISNODE users only want the node exclusive
aspect of the flag, without actually implementing their own fallback or
triggering reclaim if necessary.  This results in things like page
migration failing prematurely even when there is easily reclaimable
memory available, unless kswapd happens to be running already or a
concurrent allocation attempt triggers the necessary reclaim.

Convert all callsites that don't implement their own fallback strategy
to __GFP_THISNODE.  This restricts the allocation a single node too, but
at the same time allows the allocator to enter the slowpath, wake
kswapd, and invoke direct reclaim if necessary, to make the allocation
happen when memory is full.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Jan Stancek <jstancek@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-10 17:26:19 -07:00

423 lines
15 KiB
C

#ifndef __LINUX_GFP_H
#define __LINUX_GFP_H
#include <linux/mmdebug.h>
#include <linux/mmzone.h>
#include <linux/stddef.h>
#include <linux/linkage.h>
#include <linux/topology.h>
#include <linux/mmdebug.h>
struct vm_area_struct;
/* Plain integer GFP bitmasks. Do not use this directly. */
#define ___GFP_DMA 0x01u
#define ___GFP_HIGHMEM 0x02u
#define ___GFP_DMA32 0x04u
#define ___GFP_MOVABLE 0x08u
#define ___GFP_WAIT 0x10u
#define ___GFP_HIGH 0x20u
#define ___GFP_IO 0x40u
#define ___GFP_FS 0x80u
#define ___GFP_COLD 0x100u
#define ___GFP_NOWARN 0x200u
#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
#define ___GFP_HARDWALL 0x20000u
#define ___GFP_THISNODE 0x40000u
#define ___GFP_RECLAIMABLE 0x80000u
#define ___GFP_KMEMCG 0x100000u
#define ___GFP_NOTRACK 0x200000u
#define ___GFP_NO_KSWAPD 0x400000u
#define ___GFP_OTHER_NODE 0x800000u
#define ___GFP_WRITE 0x1000000u
/* If the above are modified, __GFP_BITS_SHIFT may need updating */
/*
* GFP bitmasks..
*
* Zone modifiers (see linux/mmzone.h - low three bits)
*
* Do not put any conditional on these. If necessary modify the definitions
* without the underscores and use them consistently. The definitions here may
* be used in bit comparisons.
*/
#define __GFP_DMA ((__force gfp_t)___GFP_DMA)
#define __GFP_HIGHMEM ((__force gfp_t)___GFP_HIGHMEM)
#define __GFP_DMA32 ((__force gfp_t)___GFP_DMA32)
#define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* Page is movable */
#define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
/*
* Action modifiers - doesn't change the zoning
*
* __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
* _might_ fail. This depends upon the particular VM implementation.
*
* __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
* cannot handle allocation failures. This modifier is deprecated and no new
* users should be added.
*
* __GFP_NORETRY: The VM implementation must not retry indefinitely.
*
* __GFP_MOVABLE: Flag that this page will be movable by the page migration
* mechanism or reclaimed
*/
#define __GFP_WAIT ((__force gfp_t)___GFP_WAIT) /* Can wait and reschedule? */
#define __GFP_HIGH ((__force gfp_t)___GFP_HIGH) /* Should access emergency pools? */
#define __GFP_IO ((__force gfp_t)___GFP_IO) /* Can start physical IO? */
#define __GFP_FS ((__force gfp_t)___GFP_FS) /* Can call down to low-level FS? */
#define __GFP_COLD ((__force gfp_t)___GFP_COLD) /* Cache-cold page required */
#define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN) /* Suppress page allocation failure warning */
#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.
* 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 */
#define __GFP_NOTRACK ((__force gfp_t)___GFP_NOTRACK) /* Don't track with kmemcheck */
#define __GFP_NO_KSWAPD ((__force gfp_t)___GFP_NO_KSWAPD)
#define __GFP_OTHER_NODE ((__force gfp_t)___GFP_OTHER_NODE) /* On behalf of other node */
#define __GFP_KMEMCG ((__force gfp_t)___GFP_KMEMCG) /* Allocation comes from a memcg-accounted resource */
#define __GFP_WRITE ((__force gfp_t)___GFP_WRITE) /* Allocator intends to dirty page */
/*
* This may seem redundant, but it's a way of annotating false positives vs.
* allocations that simply cannot be supported (e.g. page tables).
*/
#define __GFP_NOTRACK_FALSE_POSITIVE (__GFP_NOTRACK)
#define __GFP_BITS_SHIFT 25 /* Room for N __GFP_FOO bits */
#define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
/* This equals 0, but use constants in case they ever change */
#define GFP_NOWAIT (GFP_ATOMIC & ~__GFP_HIGH)
/* GFP_ATOMIC means both !wait (__GFP_WAIT not set) and use emergency pool */
#define GFP_ATOMIC (__GFP_HIGH)
#define GFP_NOIO (__GFP_WAIT)
#define GFP_NOFS (__GFP_WAIT | __GFP_IO)
#define GFP_KERNEL (__GFP_WAIT | __GFP_IO | __GFP_FS)
#define GFP_TEMPORARY (__GFP_WAIT | __GFP_IO | __GFP_FS | \
__GFP_RECLAIMABLE)
#define GFP_USER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
#define GFP_HIGHUSER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL | \
__GFP_HIGHMEM)
#define GFP_HIGHUSER_MOVABLE (__GFP_WAIT | __GFP_IO | __GFP_FS | \
__GFP_HARDWALL | __GFP_HIGHMEM | \
__GFP_MOVABLE)
#define GFP_IOFS (__GFP_IO | __GFP_FS)
#define GFP_TRANSHUGE (GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
__GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | \
__GFP_NO_KSWAPD)
/*
* GFP_THISNODE does not perform any reclaim, you most likely want to
* use __GFP_THISNODE to allocate from a given node without fallback!
*/
#ifdef CONFIG_NUMA
#define GFP_THISNODE (__GFP_THISNODE | __GFP_NOWARN | __GFP_NORETRY)
#else
#define GFP_THISNODE ((__force gfp_t)0)
#endif
/* This mask makes up all the page movable related flags */
#define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
/* 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_MEMALLOC|__GFP_NOMEMALLOC)
/* Control slab gfp mask during early boot */
#define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_WAIT|__GFP_IO|__GFP_FS))
/* Control allocation constraints */
#define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)
/* Do not use these with a slab allocator */
#define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
/* Flag - indicates that the buffer will be suitable for DMA. Ignored on some
platforms, used as appropriate on others */
#define GFP_DMA __GFP_DMA
/* 4GB DMA on some platforms */
#define GFP_DMA32 __GFP_DMA32
/* Convert GFP flags to their corresponding migrate type */
static inline int allocflags_to_migratetype(gfp_t gfp_flags)
{
WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
if (unlikely(page_group_by_mobility_disabled))
return MIGRATE_UNMOVABLE;
/* Group based on mobility */
return (((gfp_flags & __GFP_MOVABLE) != 0) << 1) |
((gfp_flags & __GFP_RECLAIMABLE) != 0);
}
#ifdef CONFIG_HIGHMEM
#define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
#else
#define OPT_ZONE_HIGHMEM ZONE_NORMAL
#endif
#ifdef CONFIG_ZONE_DMA
#define OPT_ZONE_DMA ZONE_DMA
#else
#define OPT_ZONE_DMA ZONE_NORMAL
#endif
#ifdef CONFIG_ZONE_DMA32
#define OPT_ZONE_DMA32 ZONE_DMA32
#else
#define OPT_ZONE_DMA32 ZONE_NORMAL
#endif
/*
* GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
* zone to use given the lowest 4 bits of gfp_t. Entries are ZONE_SHIFT long
* and there are 16 of them to cover all possible combinations of
* __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
*
* The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
* But GFP_MOVABLE is not only a zone specifier but also an allocation
* policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
* Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
*
* bit result
* =================
* 0x0 => NORMAL
* 0x1 => DMA or NORMAL
* 0x2 => HIGHMEM or NORMAL
* 0x3 => BAD (DMA+HIGHMEM)
* 0x4 => DMA32 or DMA or NORMAL
* 0x5 => BAD (DMA+DMA32)
* 0x6 => BAD (HIGHMEM+DMA32)
* 0x7 => BAD (HIGHMEM+DMA32+DMA)
* 0x8 => NORMAL (MOVABLE+0)
* 0x9 => DMA or NORMAL (MOVABLE+DMA)
* 0xa => MOVABLE (Movable is valid only if HIGHMEM is set too)
* 0xb => BAD (MOVABLE+HIGHMEM+DMA)
* 0xc => DMA32 (MOVABLE+DMA32)
* 0xd => BAD (MOVABLE+DMA32+DMA)
* 0xe => BAD (MOVABLE+DMA32+HIGHMEM)
* 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
*
* ZONES_SHIFT must be <= 2 on 32 bit platforms.
*/
#if 16 * ZONES_SHIFT > BITS_PER_LONG
#error ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
#endif
#define GFP_ZONE_TABLE ( \
(ZONE_NORMAL << 0 * ZONES_SHIFT) \
| (OPT_ZONE_DMA << ___GFP_DMA * ZONES_SHIFT) \
| (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * ZONES_SHIFT) \
| (OPT_ZONE_DMA32 << ___GFP_DMA32 * ZONES_SHIFT) \
| (ZONE_NORMAL << ___GFP_MOVABLE * ZONES_SHIFT) \
| (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * ZONES_SHIFT) \
| (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * ZONES_SHIFT) \
| (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * ZONES_SHIFT) \
)
/*
* GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32
* __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
* entry starting with bit 0. Bit is set if the combination is not
* allowed.
*/
#define GFP_ZONE_BAD ( \
1 << (___GFP_DMA | ___GFP_HIGHMEM) \
| 1 << (___GFP_DMA | ___GFP_DMA32) \
| 1 << (___GFP_DMA32 | ___GFP_HIGHMEM) \
| 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM) \
| 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA) \
| 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA) \
| 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM) \
| 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM) \
)
static inline enum zone_type gfp_zone(gfp_t flags)
{
enum zone_type z;
int bit = (__force int) (flags & GFP_ZONEMASK);
z = (GFP_ZONE_TABLE >> (bit * ZONES_SHIFT)) &
((1 << ZONES_SHIFT) - 1);
VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
return z;
}
/*
* There is only one page-allocator function, and two main namespaces to
* it. The alloc_page*() variants return 'struct page *' and as such
* can allocate highmem pages, the *get*page*() variants return
* virtual kernel addresses to the allocated page(s).
*/
static inline int gfp_zonelist(gfp_t flags)
{
if (IS_ENABLED(CONFIG_NUMA) && unlikely(flags & __GFP_THISNODE))
return 1;
return 0;
}
/*
* We get the zone list from the current node and the gfp_mask.
* This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
* There are two zonelists per node, one for all zones with memory and
* one containing just zones from the node the zonelist belongs to.
*
* For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
* optimized to &contig_page_data at compile-time.
*/
static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
{
return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
}
#ifndef HAVE_ARCH_FREE_PAGE
static inline void arch_free_page(struct page *page, int order) { }
#endif
#ifndef HAVE_ARCH_ALLOC_PAGE
static inline void arch_alloc_page(struct page *page, int order) { }
#endif
struct page *
__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
struct zonelist *zonelist, nodemask_t *nodemask);
static inline struct page *
__alloc_pages(gfp_t gfp_mask, unsigned int order,
struct zonelist *zonelist)
{
return __alloc_pages_nodemask(gfp_mask, order, zonelist, NULL);
}
static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
unsigned int order)
{
/* Unknown node is current node */
if (nid < 0)
nid = numa_node_id();
return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
}
static inline struct page *alloc_pages_exact_node(int nid, gfp_t gfp_mask,
unsigned int order)
{
VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES || !node_online(nid));
return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
}
#ifdef CONFIG_NUMA
extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
static inline struct page *
alloc_pages(gfp_t gfp_mask, unsigned int order)
{
return alloc_pages_current(gfp_mask, order);
}
extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
struct vm_area_struct *vma, unsigned long addr,
int node);
#else
#define alloc_pages(gfp_mask, order) \
alloc_pages_node(numa_node_id(), gfp_mask, order)
#define alloc_pages_vma(gfp_mask, order, vma, addr, node) \
alloc_pages(gfp_mask, order)
#endif
#define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
#define alloc_page_vma(gfp_mask, vma, addr) \
alloc_pages_vma(gfp_mask, 0, vma, addr, numa_node_id())
#define alloc_page_vma_node(gfp_mask, vma, addr, node) \
alloc_pages_vma(gfp_mask, 0, vma, addr, node)
extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
extern unsigned long get_zeroed_page(gfp_t gfp_mask);
void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
void free_pages_exact(void *virt, size_t size);
/* This is different from alloc_pages_exact_node !!! */
void *alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask);
#define __get_free_page(gfp_mask) \
__get_free_pages((gfp_mask), 0)
#define __get_dma_pages(gfp_mask, order) \
__get_free_pages((gfp_mask) | GFP_DMA, (order))
extern void __free_pages(struct page *page, unsigned int order);
extern void free_pages(unsigned long addr, unsigned int order);
extern void free_hot_cold_page(struct page *page, int cold);
extern void free_hot_cold_page_list(struct list_head *list, int cold);
extern void __free_memcg_kmem_pages(struct page *page, unsigned int order);
extern void free_memcg_kmem_pages(unsigned long addr, unsigned int order);
#define __free_page(page) __free_pages((page), 0)
#define free_page(addr) free_pages((addr), 0)
void page_alloc_init(void);
void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
void drain_all_pages(void);
void drain_local_pages(void *dummy);
/*
* gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
* GFP flags are used before interrupts are enabled. Once interrupts are
* enabled, it is set to __GFP_BITS_MASK while the system is running. During
* hibernation, it is used by PM to avoid I/O during memory allocation while
* devices are suspended.
*/
extern gfp_t gfp_allowed_mask;
/* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */
bool gfp_pfmemalloc_allowed(gfp_t gfp_mask);
extern void pm_restrict_gfp_mask(void);
extern void pm_restore_gfp_mask(void);
#ifdef CONFIG_PM_SLEEP
extern bool pm_suspended_storage(void);
#else
static inline bool pm_suspended_storage(void)
{
return false;
}
#endif /* CONFIG_PM_SLEEP */
#ifdef CONFIG_CMA
/* The below functions must be run on a range from a single zone. */
extern int alloc_contig_range(unsigned long start, unsigned long end,
unsigned migratetype);
extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
/* CMA stuff */
extern void init_cma_reserved_pageblock(struct page *page);
#endif
#endif /* __LINUX_GFP_H */