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![Michal Hocko](/assets/img/avatar_default.png)
While it might be really clear to MM developers that gfp reclaim modifiers are applicable only to sleepable allocations (those with __GFP_DIRECT_RECLAIM) it seems that actual users of the API are not always sure. Make it explicit that they are not applicable for GFP_NOWAIT or GFP_ATOMIC allocations which are the most commonly used non-sleepable allocation masks. Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Acked-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Neil Brown <neilb@suse.de> Link: http://lkml.kernel.org/r/20200403083543.11552-3-mhocko@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
633 lines
24 KiB
C
633 lines
24 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __LINUX_GFP_H
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#define __LINUX_GFP_H
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#include <linux/mmdebug.h>
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#include <linux/mmzone.h>
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#include <linux/stddef.h>
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#include <linux/linkage.h>
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#include <linux/topology.h>
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struct vm_area_struct;
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/*
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* In case of changes, please don't forget to update
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* include/trace/events/mmflags.h and tools/perf/builtin-kmem.c
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*/
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/* Plain integer GFP bitmasks. Do not use this directly. */
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#define ___GFP_DMA 0x01u
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#define ___GFP_HIGHMEM 0x02u
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#define ___GFP_DMA32 0x04u
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#define ___GFP_MOVABLE 0x08u
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#define ___GFP_RECLAIMABLE 0x10u
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#define ___GFP_HIGH 0x20u
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#define ___GFP_IO 0x40u
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#define ___GFP_FS 0x80u
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#define ___GFP_ZERO 0x100u
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#define ___GFP_ATOMIC 0x200u
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#define ___GFP_DIRECT_RECLAIM 0x400u
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#define ___GFP_KSWAPD_RECLAIM 0x800u
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#define ___GFP_WRITE 0x1000u
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#define ___GFP_NOWARN 0x2000u
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#define ___GFP_RETRY_MAYFAIL 0x4000u
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#define ___GFP_NOFAIL 0x8000u
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#define ___GFP_NORETRY 0x10000u
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#define ___GFP_MEMALLOC 0x20000u
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#define ___GFP_COMP 0x40000u
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#define ___GFP_NOMEMALLOC 0x80000u
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#define ___GFP_HARDWALL 0x100000u
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#define ___GFP_THISNODE 0x200000u
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#define ___GFP_ACCOUNT 0x400000u
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#ifdef CONFIG_LOCKDEP
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#define ___GFP_NOLOCKDEP 0x800000u
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#else
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#define ___GFP_NOLOCKDEP 0
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#endif
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/* If the above are modified, __GFP_BITS_SHIFT may need updating */
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/*
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* Physical address zone modifiers (see linux/mmzone.h - low four bits)
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*
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* Do not put any conditional on these. If necessary modify the definitions
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* without the underscores and use them consistently. The definitions here may
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* be used in bit comparisons.
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*/
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#define __GFP_DMA ((__force gfp_t)___GFP_DMA)
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#define __GFP_HIGHMEM ((__force gfp_t)___GFP_HIGHMEM)
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#define __GFP_DMA32 ((__force gfp_t)___GFP_DMA32)
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#define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* ZONE_MOVABLE allowed */
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#define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
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/**
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* DOC: Page mobility and placement hints
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*
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* Page mobility and placement hints
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* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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*
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* These flags provide hints about how mobile the page is. Pages with similar
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* mobility are placed within the same pageblocks to minimise problems due
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* to external fragmentation.
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*
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* %__GFP_MOVABLE (also a zone modifier) indicates that the page can be
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* moved by page migration during memory compaction or can be reclaimed.
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*
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* %__GFP_RECLAIMABLE is used for slab allocations that specify
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* SLAB_RECLAIM_ACCOUNT and whose pages can be freed via shrinkers.
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*
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* %__GFP_WRITE indicates the caller intends to dirty the page. Where possible,
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* these pages will be spread between local zones to avoid all the dirty
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* pages being in one zone (fair zone allocation policy).
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*
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* %__GFP_HARDWALL enforces the cpuset memory allocation policy.
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*
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* %__GFP_THISNODE forces the allocation to be satisfied from the requested
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* node with no fallbacks or placement policy enforcements.
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*
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* %__GFP_ACCOUNT causes the allocation to be accounted to kmemcg.
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*/
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#define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE)
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#define __GFP_WRITE ((__force gfp_t)___GFP_WRITE)
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#define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL)
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#define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE)
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#define __GFP_ACCOUNT ((__force gfp_t)___GFP_ACCOUNT)
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/**
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* DOC: Watermark modifiers
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*
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* Watermark modifiers -- controls access to emergency reserves
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* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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*
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* %__GFP_HIGH indicates that the caller is high-priority and that granting
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* the request is necessary before the system can make forward progress.
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* For example, creating an IO context to clean pages.
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*
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* %__GFP_ATOMIC indicates that the caller cannot reclaim or sleep and is
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* high priority. Users are typically interrupt handlers. This may be
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* used in conjunction with %__GFP_HIGH
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*
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* %__GFP_MEMALLOC allows access to all memory. This should only be used when
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* the caller guarantees the allocation will allow more memory to be freed
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* very shortly e.g. process exiting or swapping. Users either should
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* be the MM or co-ordinating closely with the VM (e.g. swap over NFS).
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*
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* %__GFP_NOMEMALLOC is used to explicitly forbid access to emergency reserves.
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* This takes precedence over the %__GFP_MEMALLOC flag if both are set.
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*/
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#define __GFP_ATOMIC ((__force gfp_t)___GFP_ATOMIC)
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#define __GFP_HIGH ((__force gfp_t)___GFP_HIGH)
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#define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC)
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#define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC)
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/**
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* DOC: Reclaim modifiers
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*
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* Reclaim modifiers
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* ~~~~~~~~~~~~~~~~~
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* Please note that all the following flags are only applicable to sleepable
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* allocations (e.g. %GFP_NOWAIT and %GFP_ATOMIC will ignore them).
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*
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* %__GFP_IO can start physical IO.
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*
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* %__GFP_FS can call down to the low-level FS. Clearing the flag avoids the
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* allocator recursing into the filesystem which might already be holding
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* locks.
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*
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* %__GFP_DIRECT_RECLAIM indicates that the caller may enter direct reclaim.
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* This flag can be cleared to avoid unnecessary delays when a fallback
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* option is available.
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*
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* %__GFP_KSWAPD_RECLAIM indicates that the caller wants to wake kswapd when
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* the low watermark is reached and have it reclaim pages until the high
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* watermark is reached. A caller may wish to clear this flag when fallback
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* options are available and the reclaim is likely to disrupt the system. The
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* canonical example is THP allocation where a fallback is cheap but
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* reclaim/compaction may cause indirect stalls.
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*
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* %__GFP_RECLAIM is shorthand to allow/forbid both direct and kswapd reclaim.
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*
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* The default allocator behavior depends on the request size. We have a concept
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* of so called costly allocations (with order > %PAGE_ALLOC_COSTLY_ORDER).
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* !costly allocations are too essential to fail so they are implicitly
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* non-failing by default (with some exceptions like OOM victims might fail so
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* the caller still has to check for failures) while costly requests try to be
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* not disruptive and back off even without invoking the OOM killer.
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* The following three modifiers might be used to override some of these
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* implicit rules
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*
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* %__GFP_NORETRY: The VM implementation will try only very lightweight
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* memory direct reclaim to get some memory under memory pressure (thus
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* it can sleep). It will avoid disruptive actions like OOM killer. The
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* caller must handle the failure which is quite likely to happen under
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* heavy memory pressure. The flag is suitable when failure can easily be
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* handled at small cost, such as reduced throughput
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*
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* %__GFP_RETRY_MAYFAIL: The VM implementation will retry memory reclaim
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* procedures that have previously failed if there is some indication
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* that progress has been made else where. It can wait for other
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* tasks to attempt high level approaches to freeing memory such as
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* compaction (which removes fragmentation) and page-out.
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* There is still a definite limit to the number of retries, but it is
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* a larger limit than with %__GFP_NORETRY.
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* Allocations with this flag may fail, but only when there is
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* genuinely little unused memory. While these allocations do not
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* directly trigger the OOM killer, their failure indicates that
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* the system is likely to need to use the OOM killer soon. The
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* caller must handle failure, but can reasonably do so by failing
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* a higher-level request, or completing it only in a much less
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* efficient manner.
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* If the allocation does fail, and the caller is in a position to
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* free some non-essential memory, doing so could benefit the system
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* as a whole.
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*
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* %__GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
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* cannot handle allocation failures. The allocation could block
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* indefinitely but will never return with failure. Testing for
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* failure is pointless.
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* New users should be evaluated carefully (and the flag should be
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* used only when there is no reasonable failure policy) but it is
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* definitely preferable to use the flag rather than opencode endless
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* loop around allocator.
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* Using this flag for costly allocations is _highly_ discouraged.
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*/
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#define __GFP_IO ((__force gfp_t)___GFP_IO)
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#define __GFP_FS ((__force gfp_t)___GFP_FS)
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#define __GFP_DIRECT_RECLAIM ((__force gfp_t)___GFP_DIRECT_RECLAIM) /* Caller can reclaim */
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#define __GFP_KSWAPD_RECLAIM ((__force gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */
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#define __GFP_RECLAIM ((__force gfp_t)(___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM))
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#define __GFP_RETRY_MAYFAIL ((__force gfp_t)___GFP_RETRY_MAYFAIL)
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#define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL)
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#define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY)
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/**
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* DOC: Action modifiers
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*
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* Action modifiers
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* ~~~~~~~~~~~~~~~~
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*
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* %__GFP_NOWARN suppresses allocation failure reports.
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*
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* %__GFP_COMP address compound page metadata.
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*
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* %__GFP_ZERO returns a zeroed page on success.
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*/
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#define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN)
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#define __GFP_COMP ((__force gfp_t)___GFP_COMP)
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#define __GFP_ZERO ((__force gfp_t)___GFP_ZERO)
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/* Disable lockdep for GFP context tracking */
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#define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP)
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/* Room for N __GFP_FOO bits */
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#define __GFP_BITS_SHIFT (23 + IS_ENABLED(CONFIG_LOCKDEP))
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#define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
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/**
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* DOC: Useful GFP flag combinations
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*
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* Useful GFP flag combinations
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* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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*
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* Useful GFP flag combinations that are commonly used. It is recommended
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* that subsystems start with one of these combinations and then set/clear
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* %__GFP_FOO flags as necessary.
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*
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* %GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower
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* watermark is applied to allow access to "atomic reserves"
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*
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* %GFP_KERNEL is typical for kernel-internal allocations. The caller requires
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* %ZONE_NORMAL or a lower zone for direct access but can direct reclaim.
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*
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* %GFP_KERNEL_ACCOUNT is the same as GFP_KERNEL, except the allocation is
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* accounted to kmemcg.
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*
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* %GFP_NOWAIT is for kernel allocations that should not stall for direct
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* reclaim, start physical IO or use any filesystem callback.
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*
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* %GFP_NOIO will use direct reclaim to discard clean pages or slab pages
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* that do not require the starting of any physical IO.
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* Please try to avoid using this flag directly and instead use
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* memalloc_noio_{save,restore} to mark the whole scope which cannot
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* perform any IO with a short explanation why. All allocation requests
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* will inherit GFP_NOIO implicitly.
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*
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* %GFP_NOFS will use direct reclaim but will not use any filesystem interfaces.
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* Please try to avoid using this flag directly and instead use
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* memalloc_nofs_{save,restore} to mark the whole scope which cannot/shouldn't
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* recurse into the FS layer with a short explanation why. All allocation
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* requests will inherit GFP_NOFS implicitly.
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*
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* %GFP_USER is for userspace allocations that also need to be directly
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* accessibly by the kernel or hardware. It is typically used by hardware
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* for buffers that are mapped to userspace (e.g. graphics) that hardware
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* still must DMA to. cpuset limits are enforced for these allocations.
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*
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* %GFP_DMA exists for historical reasons and should be avoided where possible.
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* The flags indicates that the caller requires that the lowest zone be
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* used (%ZONE_DMA or 16M on x86-64). Ideally, this would be removed but
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* it would require careful auditing as some users really require it and
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* others use the flag to avoid lowmem reserves in %ZONE_DMA and treat the
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* lowest zone as a type of emergency reserve.
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*
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* %GFP_DMA32 is similar to %GFP_DMA except that the caller requires a 32-bit
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* address.
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*
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* %GFP_HIGHUSER is for userspace allocations that may be mapped to userspace,
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* do not need to be directly accessible by the kernel but that cannot
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* move once in use. An example may be a hardware allocation that maps
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* data directly into userspace but has no addressing limitations.
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*
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* %GFP_HIGHUSER_MOVABLE is for userspace allocations that the kernel does not
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* need direct access to but can use kmap() when access is required. They
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* are expected to be movable via page reclaim or page migration. Typically,
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* pages on the LRU would also be allocated with %GFP_HIGHUSER_MOVABLE.
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*
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* %GFP_TRANSHUGE and %GFP_TRANSHUGE_LIGHT are used for THP allocations. They
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* are compound allocations that will generally fail quickly if memory is not
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* available and will not wake kswapd/kcompactd on failure. The _LIGHT
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* version does not attempt reclaim/compaction at all and is by default used
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* in page fault path, while the non-light is used by khugepaged.
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*/
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#define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM)
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#define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS)
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#define GFP_KERNEL_ACCOUNT (GFP_KERNEL | __GFP_ACCOUNT)
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#define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM)
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#define GFP_NOIO (__GFP_RECLAIM)
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#define GFP_NOFS (__GFP_RECLAIM | __GFP_IO)
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#define GFP_USER (__GFP_RECLAIM | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
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#define GFP_DMA __GFP_DMA
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#define GFP_DMA32 __GFP_DMA32
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#define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM)
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#define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE)
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#define GFP_TRANSHUGE_LIGHT ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
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__GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM)
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#define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_RECLAIM)
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/* Convert GFP flags to their corresponding migrate type */
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#define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
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#define GFP_MOVABLE_SHIFT 3
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static inline int gfpflags_to_migratetype(const gfp_t gfp_flags)
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{
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VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
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BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE);
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BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE);
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if (unlikely(page_group_by_mobility_disabled))
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return MIGRATE_UNMOVABLE;
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/* Group based on mobility */
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return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT;
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}
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#undef GFP_MOVABLE_MASK
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#undef GFP_MOVABLE_SHIFT
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static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
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{
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return !!(gfp_flags & __GFP_DIRECT_RECLAIM);
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}
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/**
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* gfpflags_normal_context - is gfp_flags a normal sleepable context?
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* @gfp_flags: gfp_flags to test
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*
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* Test whether @gfp_flags indicates that the allocation is from the
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* %current context and allowed to sleep.
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*
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* An allocation being allowed to block doesn't mean it owns the %current
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* context. When direct reclaim path tries to allocate memory, the
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* allocation context is nested inside whatever %current was doing at the
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* time of the original allocation. The nested allocation may be allowed
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* to block but modifying anything %current owns can corrupt the outer
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* context's expectations.
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*
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* %true result from this function indicates that the allocation context
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* can sleep and use anything that's associated with %current.
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*/
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static inline bool gfpflags_normal_context(const gfp_t gfp_flags)
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{
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return (gfp_flags & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC)) ==
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__GFP_DIRECT_RECLAIM;
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}
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#ifdef CONFIG_HIGHMEM
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#define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
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#else
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#define OPT_ZONE_HIGHMEM ZONE_NORMAL
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#endif
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#ifdef CONFIG_ZONE_DMA
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#define OPT_ZONE_DMA ZONE_DMA
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#else
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#define OPT_ZONE_DMA ZONE_NORMAL
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#endif
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#ifdef CONFIG_ZONE_DMA32
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#define OPT_ZONE_DMA32 ZONE_DMA32
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#else
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#define OPT_ZONE_DMA32 ZONE_NORMAL
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#endif
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/*
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* GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
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* zone to use given the lowest 4 bits of gfp_t. Entries are GFP_ZONES_SHIFT
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* bits long and there are 16 of them to cover all possible combinations of
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* __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
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*
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* The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
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* But GFP_MOVABLE is not only a zone specifier but also an allocation
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* policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
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* Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
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*
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* bit result
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* =================
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* 0x0 => NORMAL
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* 0x1 => DMA or NORMAL
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* 0x2 => HIGHMEM or NORMAL
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* 0x3 => BAD (DMA+HIGHMEM)
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* 0x4 => DMA32 or NORMAL
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* 0x5 => BAD (DMA+DMA32)
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* 0x6 => BAD (HIGHMEM+DMA32)
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* 0x7 => BAD (HIGHMEM+DMA32+DMA)
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* 0x8 => NORMAL (MOVABLE+0)
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* 0x9 => DMA or NORMAL (MOVABLE+DMA)
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* 0xa => MOVABLE (Movable is valid only if HIGHMEM is set too)
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* 0xb => BAD (MOVABLE+HIGHMEM+DMA)
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* 0xc => DMA32 or NORMAL (MOVABLE+DMA32)
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* 0xd => BAD (MOVABLE+DMA32+DMA)
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* 0xe => BAD (MOVABLE+DMA32+HIGHMEM)
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* 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
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*
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* GFP_ZONES_SHIFT must be <= 2 on 32 bit platforms.
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*/
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#if defined(CONFIG_ZONE_DEVICE) && (MAX_NR_ZONES-1) <= 4
|
|
/* ZONE_DEVICE is not a valid GFP zone specifier */
|
|
#define GFP_ZONES_SHIFT 2
|
|
#else
|
|
#define GFP_ZONES_SHIFT ZONES_SHIFT
|
|
#endif
|
|
|
|
#if 16 * GFP_ZONES_SHIFT > BITS_PER_LONG
|
|
#error GFP_ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
|
|
#endif
|
|
|
|
#define GFP_ZONE_TABLE ( \
|
|
(ZONE_NORMAL << 0 * GFP_ZONES_SHIFT) \
|
|
| (OPT_ZONE_DMA << ___GFP_DMA * GFP_ZONES_SHIFT) \
|
|
| (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * GFP_ZONES_SHIFT) \
|
|
| (OPT_ZONE_DMA32 << ___GFP_DMA32 * GFP_ZONES_SHIFT) \
|
|
| (ZONE_NORMAL << ___GFP_MOVABLE * GFP_ZONES_SHIFT) \
|
|
| (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * GFP_ZONES_SHIFT) \
|
|
| (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * GFP_ZONES_SHIFT)\
|
|
| (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * GFP_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 * GFP_ZONES_SHIFT)) &
|
|
((1 << GFP_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)
|
|
{
|
|
#ifdef CONFIG_NUMA
|
|
if (unlikely(flags & __GFP_THISNODE))
|
|
return ZONELIST_NOFALLBACK;
|
|
#endif
|
|
return ZONELIST_FALLBACK;
|
|
}
|
|
|
|
/*
|
|
* 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
|
|
#ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE
|
|
static inline int arch_make_page_accessible(struct page *page)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
struct page *
|
|
__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid,
|
|
nodemask_t *nodemask);
|
|
|
|
static inline struct page *
|
|
__alloc_pages(gfp_t gfp_mask, unsigned int order, int preferred_nid)
|
|
{
|
|
return __alloc_pages_nodemask(gfp_mask, order, preferred_nid, NULL);
|
|
}
|
|
|
|
/*
|
|
* Allocate pages, preferring the node given as nid. The node must be valid and
|
|
* online. For more general interface, see alloc_pages_node().
|
|
*/
|
|
static inline struct page *
|
|
__alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
|
|
{
|
|
VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
|
|
VM_WARN_ON((gfp_mask & __GFP_THISNODE) && !node_online(nid));
|
|
|
|
return __alloc_pages(gfp_mask, order, nid);
|
|
}
|
|
|
|
/*
|
|
* Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE,
|
|
* prefer the current CPU's closest node. Otherwise node must be valid and
|
|
* online.
|
|
*/
|
|
static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
|
|
unsigned int order)
|
|
{
|
|
if (nid == NUMA_NO_NODE)
|
|
nid = numa_mem_id();
|
|
|
|
return __alloc_pages_node(nid, gfp_mask, order);
|
|
}
|
|
|
|
#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, bool hugepage);
|
|
#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
|
|
alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
|
|
#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, false)\
|
|
alloc_pages(gfp_mask, order)
|
|
#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
|
|
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(), false)
|
|
#define alloc_page_vma_node(gfp_mask, vma, addr, node) \
|
|
alloc_pages_vma(gfp_mask, 0, vma, addr, node, false)
|
|
|
|
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);
|
|
void * __meminit 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_unref_page(struct page *page);
|
|
extern void free_unref_page_list(struct list_head *list);
|
|
|
|
struct page_frag_cache;
|
|
extern void __page_frag_cache_drain(struct page *page, unsigned int count);
|
|
extern void *page_frag_alloc(struct page_frag_cache *nc,
|
|
unsigned int fragsz, gfp_t gfp_mask);
|
|
extern void page_frag_free(void *addr);
|
|
|
|
#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(struct zone *zone);
|
|
void drain_local_pages(struct zone *zone);
|
|
|
|
void page_alloc_init_late(void);
|
|
|
|
/*
|
|
* 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_CONTIG_ALLOC
|
|
/* 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, gfp_t gfp_mask);
|
|
extern struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask,
|
|
int nid, nodemask_t *nodemask);
|
|
#endif
|
|
void free_contig_range(unsigned long pfn, unsigned int nr_pages);
|
|
|
|
#ifdef CONFIG_CMA
|
|
/* CMA stuff */
|
|
extern void init_cma_reserved_pageblock(struct page *page);
|
|
#endif
|
|
|
|
#endif /* __LINUX_GFP_H */
|