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95d6c701f4
Extracted from slab.h, which seems to have the most complete version including the correct might_sleep() check. Roll it out to slob.c. Motivated by a discussion with Paul about possibly changing call_rcu behaviour to allocate memory, but only roughly every 500th call. There are a lot fewer places in the kernel that care about whether allocating memory is allowed or not (due to deadlocks with reclaim code) than places that care whether sleeping is allowed. But debugging these also tends to be a lot harder, so nice descriptive checks could come in handy. I might have some use eventually for annotations in drivers/gpu. Note that unlike fs_reclaim_acquire/release gfpflags_allow_blocking does not consult the PF_MEMALLOC flags. But there is no flag equivalent for GFP_NOWAIT, hence this check can't go wrong due to memalloc_no*_save/restore contexts. Willy is working on a patch series which might change this: https://lore.kernel.org/linux-mm/20200625113122.7540-7-willy@infradead.org/ I think best would be if that updates gfpflags_allow_blocking(), since there's a ton of callers all over the place for that already. Link: https://lkml.kernel.org/r/20201125162532.1299794-3-daniel.vetter@ffwll.ch Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Michel Lespinasse <walken@google.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Waiman Long <longman@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Qian Cai <cai@lca.pw> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Christian König <christian.koenig@amd.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Thomas Hellström (Intel) <thomas_os@shipmail.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
719 lines
18 KiB
C
719 lines
18 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* SLOB Allocator: Simple List Of Blocks
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*
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* Matt Mackall <mpm@selenic.com> 12/30/03
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*
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* NUMA support by Paul Mundt, 2007.
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*
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* How SLOB works:
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*
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* The core of SLOB is a traditional K&R style heap allocator, with
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* support for returning aligned objects. The granularity of this
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* allocator is as little as 2 bytes, however typically most architectures
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* will require 4 bytes on 32-bit and 8 bytes on 64-bit.
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*
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* The slob heap is a set of linked list of pages from alloc_pages(),
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* and within each page, there is a singly-linked list of free blocks
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* (slob_t). The heap is grown on demand. To reduce fragmentation,
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* heap pages are segregated into three lists, with objects less than
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* 256 bytes, objects less than 1024 bytes, and all other objects.
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*
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* Allocation from heap involves first searching for a page with
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* sufficient free blocks (using a next-fit-like approach) followed by
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* a first-fit scan of the page. Deallocation inserts objects back
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* into the free list in address order, so this is effectively an
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* address-ordered first fit.
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*
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* Above this is an implementation of kmalloc/kfree. Blocks returned
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* from kmalloc are prepended with a 4-byte header with the kmalloc size.
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* If kmalloc is asked for objects of PAGE_SIZE or larger, it calls
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* alloc_pages() directly, allocating compound pages so the page order
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* does not have to be separately tracked.
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* These objects are detected in kfree() because PageSlab()
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* is false for them.
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*
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* SLAB is emulated on top of SLOB by simply calling constructors and
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* destructors for every SLAB allocation. Objects are returned with the
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* 4-byte alignment unless the SLAB_HWCACHE_ALIGN flag is set, in which
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* case the low-level allocator will fragment blocks to create the proper
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* alignment. Again, objects of page-size or greater are allocated by
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* calling alloc_pages(). As SLAB objects know their size, no separate
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* size bookkeeping is necessary and there is essentially no allocation
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* space overhead, and compound pages aren't needed for multi-page
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* allocations.
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*
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* NUMA support in SLOB is fairly simplistic, pushing most of the real
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* logic down to the page allocator, and simply doing the node accounting
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* on the upper levels. In the event that a node id is explicitly
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* provided, __alloc_pages_node() with the specified node id is used
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* instead. The common case (or when the node id isn't explicitly provided)
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* will default to the current node, as per numa_node_id().
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*
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* Node aware pages are still inserted in to the global freelist, and
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* these are scanned for by matching against the node id encoded in the
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* page flags. As a result, block allocations that can be satisfied from
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* the freelist will only be done so on pages residing on the same node,
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* in order to prevent random node placement.
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*/
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/mm.h>
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#include <linux/swap.h> /* struct reclaim_state */
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#include <linux/cache.h>
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#include <linux/init.h>
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#include <linux/export.h>
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#include <linux/rcupdate.h>
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#include <linux/list.h>
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#include <linux/kmemleak.h>
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#include <trace/events/kmem.h>
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#include <linux/atomic.h>
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#include "slab.h"
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/*
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* slob_block has a field 'units', which indicates size of block if +ve,
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* or offset of next block if -ve (in SLOB_UNITs).
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*
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* Free blocks of size 1 unit simply contain the offset of the next block.
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* Those with larger size contain their size in the first SLOB_UNIT of
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* memory, and the offset of the next free block in the second SLOB_UNIT.
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*/
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#if PAGE_SIZE <= (32767 * 2)
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typedef s16 slobidx_t;
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#else
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typedef s32 slobidx_t;
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#endif
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struct slob_block {
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slobidx_t units;
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};
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typedef struct slob_block slob_t;
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/*
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* All partially free slob pages go on these lists.
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*/
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#define SLOB_BREAK1 256
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#define SLOB_BREAK2 1024
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static LIST_HEAD(free_slob_small);
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static LIST_HEAD(free_slob_medium);
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static LIST_HEAD(free_slob_large);
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/*
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* slob_page_free: true for pages on free_slob_pages list.
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*/
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static inline int slob_page_free(struct page *sp)
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{
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return PageSlobFree(sp);
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}
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static void set_slob_page_free(struct page *sp, struct list_head *list)
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{
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list_add(&sp->slab_list, list);
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__SetPageSlobFree(sp);
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}
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static inline void clear_slob_page_free(struct page *sp)
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{
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list_del(&sp->slab_list);
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__ClearPageSlobFree(sp);
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}
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#define SLOB_UNIT sizeof(slob_t)
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#define SLOB_UNITS(size) DIV_ROUND_UP(size, SLOB_UNIT)
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/*
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* struct slob_rcu is inserted at the tail of allocated slob blocks, which
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* were created with a SLAB_TYPESAFE_BY_RCU slab. slob_rcu is used to free
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* the block using call_rcu.
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*/
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struct slob_rcu {
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struct rcu_head head;
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int size;
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};
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/*
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* slob_lock protects all slob allocator structures.
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*/
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static DEFINE_SPINLOCK(slob_lock);
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/*
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* Encode the given size and next info into a free slob block s.
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*/
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static void set_slob(slob_t *s, slobidx_t size, slob_t *next)
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{
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slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK);
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slobidx_t offset = next - base;
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if (size > 1) {
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s[0].units = size;
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s[1].units = offset;
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} else
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s[0].units = -offset;
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}
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/*
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* Return the size of a slob block.
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*/
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static slobidx_t slob_units(slob_t *s)
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{
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if (s->units > 0)
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return s->units;
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return 1;
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}
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/*
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* Return the next free slob block pointer after this one.
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*/
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static slob_t *slob_next(slob_t *s)
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{
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slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK);
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slobidx_t next;
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if (s[0].units < 0)
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next = -s[0].units;
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else
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next = s[1].units;
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return base+next;
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}
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/*
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* Returns true if s is the last free block in its page.
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*/
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static int slob_last(slob_t *s)
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{
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return !((unsigned long)slob_next(s) & ~PAGE_MASK);
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}
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static void *slob_new_pages(gfp_t gfp, int order, int node)
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{
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struct page *page;
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#ifdef CONFIG_NUMA
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if (node != NUMA_NO_NODE)
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page = __alloc_pages_node(node, gfp, order);
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else
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#endif
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page = alloc_pages(gfp, order);
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if (!page)
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return NULL;
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mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE_B,
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PAGE_SIZE << order);
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return page_address(page);
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}
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static void slob_free_pages(void *b, int order)
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{
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struct page *sp = virt_to_page(b);
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if (current->reclaim_state)
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current->reclaim_state->reclaimed_slab += 1 << order;
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mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B,
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-(PAGE_SIZE << order));
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__free_pages(sp, order);
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}
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/*
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* slob_page_alloc() - Allocate a slob block within a given slob_page sp.
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* @sp: Page to look in.
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* @size: Size of the allocation.
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* @align: Allocation alignment.
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* @align_offset: Offset in the allocated block that will be aligned.
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* @page_removed_from_list: Return parameter.
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*
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* Tries to find a chunk of memory at least @size bytes big within @page.
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*
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* Return: Pointer to memory if allocated, %NULL otherwise. If the
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* allocation fills up @page then the page is removed from the
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* freelist, in this case @page_removed_from_list will be set to
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* true (set to false otherwise).
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*/
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static void *slob_page_alloc(struct page *sp, size_t size, int align,
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int align_offset, bool *page_removed_from_list)
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{
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slob_t *prev, *cur, *aligned = NULL;
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int delta = 0, units = SLOB_UNITS(size);
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*page_removed_from_list = false;
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for (prev = NULL, cur = sp->freelist; ; prev = cur, cur = slob_next(cur)) {
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slobidx_t avail = slob_units(cur);
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/*
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* 'aligned' will hold the address of the slob block so that the
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* address 'aligned'+'align_offset' is aligned according to the
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* 'align' parameter. This is for kmalloc() which prepends the
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* allocated block with its size, so that the block itself is
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* aligned when needed.
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*/
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if (align) {
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aligned = (slob_t *)
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(ALIGN((unsigned long)cur + align_offset, align)
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- align_offset);
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delta = aligned - cur;
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}
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if (avail >= units + delta) { /* room enough? */
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slob_t *next;
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if (delta) { /* need to fragment head to align? */
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next = slob_next(cur);
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set_slob(aligned, avail - delta, next);
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set_slob(cur, delta, aligned);
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prev = cur;
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cur = aligned;
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avail = slob_units(cur);
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}
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next = slob_next(cur);
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if (avail == units) { /* exact fit? unlink. */
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if (prev)
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set_slob(prev, slob_units(prev), next);
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else
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sp->freelist = next;
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} else { /* fragment */
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if (prev)
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set_slob(prev, slob_units(prev), cur + units);
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else
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sp->freelist = cur + units;
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set_slob(cur + units, avail - units, next);
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}
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sp->units -= units;
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if (!sp->units) {
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clear_slob_page_free(sp);
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*page_removed_from_list = true;
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}
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return cur;
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}
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if (slob_last(cur))
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return NULL;
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}
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}
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/*
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* slob_alloc: entry point into the slob allocator.
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*/
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static void *slob_alloc(size_t size, gfp_t gfp, int align, int node,
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int align_offset)
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{
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struct page *sp;
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struct list_head *slob_list;
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slob_t *b = NULL;
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unsigned long flags;
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bool _unused;
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if (size < SLOB_BREAK1)
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slob_list = &free_slob_small;
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else if (size < SLOB_BREAK2)
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slob_list = &free_slob_medium;
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else
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slob_list = &free_slob_large;
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spin_lock_irqsave(&slob_lock, flags);
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/* Iterate through each partially free page, try to find room */
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list_for_each_entry(sp, slob_list, slab_list) {
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bool page_removed_from_list = false;
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#ifdef CONFIG_NUMA
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/*
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* If there's a node specification, search for a partial
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* page with a matching node id in the freelist.
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*/
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if (node != NUMA_NO_NODE && page_to_nid(sp) != node)
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continue;
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#endif
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/* Enough room on this page? */
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if (sp->units < SLOB_UNITS(size))
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continue;
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b = slob_page_alloc(sp, size, align, align_offset, &page_removed_from_list);
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if (!b)
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continue;
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/*
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* If slob_page_alloc() removed sp from the list then we
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* cannot call list functions on sp. If so allocation
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* did not fragment the page anyway so optimisation is
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* unnecessary.
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*/
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if (!page_removed_from_list) {
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/*
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* Improve fragment distribution and reduce our average
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* search time by starting our next search here. (see
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* Knuth vol 1, sec 2.5, pg 449)
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*/
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if (!list_is_first(&sp->slab_list, slob_list))
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list_rotate_to_front(&sp->slab_list, slob_list);
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}
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break;
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}
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spin_unlock_irqrestore(&slob_lock, flags);
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/* Not enough space: must allocate a new page */
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if (!b) {
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b = slob_new_pages(gfp & ~__GFP_ZERO, 0, node);
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if (!b)
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return NULL;
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sp = virt_to_page(b);
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__SetPageSlab(sp);
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spin_lock_irqsave(&slob_lock, flags);
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sp->units = SLOB_UNITS(PAGE_SIZE);
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sp->freelist = b;
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INIT_LIST_HEAD(&sp->slab_list);
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set_slob(b, SLOB_UNITS(PAGE_SIZE), b + SLOB_UNITS(PAGE_SIZE));
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set_slob_page_free(sp, slob_list);
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b = slob_page_alloc(sp, size, align, align_offset, &_unused);
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BUG_ON(!b);
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spin_unlock_irqrestore(&slob_lock, flags);
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}
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if (unlikely(gfp & __GFP_ZERO))
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memset(b, 0, size);
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return b;
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}
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/*
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* slob_free: entry point into the slob allocator.
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*/
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static void slob_free(void *block, int size)
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{
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struct page *sp;
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slob_t *prev, *next, *b = (slob_t *)block;
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slobidx_t units;
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unsigned long flags;
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struct list_head *slob_list;
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if (unlikely(ZERO_OR_NULL_PTR(block)))
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return;
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BUG_ON(!size);
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sp = virt_to_page(block);
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units = SLOB_UNITS(size);
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spin_lock_irqsave(&slob_lock, flags);
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if (sp->units + units == SLOB_UNITS(PAGE_SIZE)) {
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/* Go directly to page allocator. Do not pass slob allocator */
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if (slob_page_free(sp))
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clear_slob_page_free(sp);
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spin_unlock_irqrestore(&slob_lock, flags);
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__ClearPageSlab(sp);
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page_mapcount_reset(sp);
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slob_free_pages(b, 0);
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return;
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}
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if (!slob_page_free(sp)) {
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/* This slob page is about to become partially free. Easy! */
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sp->units = units;
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sp->freelist = b;
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set_slob(b, units,
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(void *)((unsigned long)(b +
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SLOB_UNITS(PAGE_SIZE)) & PAGE_MASK));
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if (size < SLOB_BREAK1)
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slob_list = &free_slob_small;
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else if (size < SLOB_BREAK2)
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slob_list = &free_slob_medium;
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else
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slob_list = &free_slob_large;
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set_slob_page_free(sp, slob_list);
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goto out;
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}
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/*
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* Otherwise the page is already partially free, so find reinsertion
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* point.
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*/
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sp->units += units;
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if (b < (slob_t *)sp->freelist) {
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if (b + units == sp->freelist) {
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units += slob_units(sp->freelist);
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sp->freelist = slob_next(sp->freelist);
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}
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set_slob(b, units, sp->freelist);
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sp->freelist = b;
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} else {
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prev = sp->freelist;
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next = slob_next(prev);
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while (b > next) {
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prev = next;
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next = slob_next(prev);
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}
|
|
|
|
if (!slob_last(prev) && b + units == next) {
|
|
units += slob_units(next);
|
|
set_slob(b, units, slob_next(next));
|
|
} else
|
|
set_slob(b, units, next);
|
|
|
|
if (prev + slob_units(prev) == b) {
|
|
units = slob_units(b) + slob_units(prev);
|
|
set_slob(prev, units, slob_next(b));
|
|
} else
|
|
set_slob(prev, slob_units(prev), b);
|
|
}
|
|
out:
|
|
spin_unlock_irqrestore(&slob_lock, flags);
|
|
}
|
|
|
|
/*
|
|
* End of slob allocator proper. Begin kmem_cache_alloc and kmalloc frontend.
|
|
*/
|
|
|
|
static __always_inline void *
|
|
__do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller)
|
|
{
|
|
unsigned int *m;
|
|
int minalign = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
|
|
void *ret;
|
|
|
|
gfp &= gfp_allowed_mask;
|
|
|
|
might_alloc(gfp);
|
|
|
|
if (size < PAGE_SIZE - minalign) {
|
|
int align = minalign;
|
|
|
|
/*
|
|
* For power of two sizes, guarantee natural alignment for
|
|
* kmalloc()'d objects.
|
|
*/
|
|
if (is_power_of_2(size))
|
|
align = max(minalign, (int) size);
|
|
|
|
if (!size)
|
|
return ZERO_SIZE_PTR;
|
|
|
|
m = slob_alloc(size + minalign, gfp, align, node, minalign);
|
|
|
|
if (!m)
|
|
return NULL;
|
|
*m = size;
|
|
ret = (void *)m + minalign;
|
|
|
|
trace_kmalloc_node(caller, ret,
|
|
size, size + minalign, gfp, node);
|
|
} else {
|
|
unsigned int order = get_order(size);
|
|
|
|
if (likely(order))
|
|
gfp |= __GFP_COMP;
|
|
ret = slob_new_pages(gfp, order, node);
|
|
|
|
trace_kmalloc_node(caller, ret,
|
|
size, PAGE_SIZE << order, gfp, node);
|
|
}
|
|
|
|
kmemleak_alloc(ret, size, 1, gfp);
|
|
return ret;
|
|
}
|
|
|
|
void *__kmalloc(size_t size, gfp_t gfp)
|
|
{
|
|
return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_);
|
|
}
|
|
EXPORT_SYMBOL(__kmalloc);
|
|
|
|
void *__kmalloc_track_caller(size_t size, gfp_t gfp, unsigned long caller)
|
|
{
|
|
return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, caller);
|
|
}
|
|
EXPORT_SYMBOL(__kmalloc_track_caller);
|
|
|
|
#ifdef CONFIG_NUMA
|
|
void *__kmalloc_node_track_caller(size_t size, gfp_t gfp,
|
|
int node, unsigned long caller)
|
|
{
|
|
return __do_kmalloc_node(size, gfp, node, caller);
|
|
}
|
|
EXPORT_SYMBOL(__kmalloc_node_track_caller);
|
|
#endif
|
|
|
|
void kfree(const void *block)
|
|
{
|
|
struct page *sp;
|
|
|
|
trace_kfree(_RET_IP_, block);
|
|
|
|
if (unlikely(ZERO_OR_NULL_PTR(block)))
|
|
return;
|
|
kmemleak_free(block);
|
|
|
|
sp = virt_to_page(block);
|
|
if (PageSlab(sp)) {
|
|
int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
|
|
unsigned int *m = (unsigned int *)(block - align);
|
|
slob_free(m, *m + align);
|
|
} else {
|
|
unsigned int order = compound_order(sp);
|
|
mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B,
|
|
-(PAGE_SIZE << order));
|
|
__free_pages(sp, order);
|
|
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(kfree);
|
|
|
|
/* can't use ksize for kmem_cache_alloc memory, only kmalloc */
|
|
size_t __ksize(const void *block)
|
|
{
|
|
struct page *sp;
|
|
int align;
|
|
unsigned int *m;
|
|
|
|
BUG_ON(!block);
|
|
if (unlikely(block == ZERO_SIZE_PTR))
|
|
return 0;
|
|
|
|
sp = virt_to_page(block);
|
|
if (unlikely(!PageSlab(sp)))
|
|
return page_size(sp);
|
|
|
|
align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
|
|
m = (unsigned int *)(block - align);
|
|
return SLOB_UNITS(*m) * SLOB_UNIT;
|
|
}
|
|
EXPORT_SYMBOL(__ksize);
|
|
|
|
int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags)
|
|
{
|
|
if (flags & SLAB_TYPESAFE_BY_RCU) {
|
|
/* leave room for rcu footer at the end of object */
|
|
c->size += sizeof(struct slob_rcu);
|
|
}
|
|
c->flags = flags;
|
|
return 0;
|
|
}
|
|
|
|
static void *slob_alloc_node(struct kmem_cache *c, gfp_t flags, int node)
|
|
{
|
|
void *b;
|
|
|
|
flags &= gfp_allowed_mask;
|
|
|
|
might_alloc(flags);
|
|
|
|
if (c->size < PAGE_SIZE) {
|
|
b = slob_alloc(c->size, flags, c->align, node, 0);
|
|
trace_kmem_cache_alloc_node(_RET_IP_, b, c->object_size,
|
|
SLOB_UNITS(c->size) * SLOB_UNIT,
|
|
flags, node);
|
|
} else {
|
|
b = slob_new_pages(flags, get_order(c->size), node);
|
|
trace_kmem_cache_alloc_node(_RET_IP_, b, c->object_size,
|
|
PAGE_SIZE << get_order(c->size),
|
|
flags, node);
|
|
}
|
|
|
|
if (b && c->ctor) {
|
|
WARN_ON_ONCE(flags & __GFP_ZERO);
|
|
c->ctor(b);
|
|
}
|
|
|
|
kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags);
|
|
return b;
|
|
}
|
|
|
|
void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags)
|
|
{
|
|
return slob_alloc_node(cachep, flags, NUMA_NO_NODE);
|
|
}
|
|
EXPORT_SYMBOL(kmem_cache_alloc);
|
|
|
|
#ifdef CONFIG_NUMA
|
|
void *__kmalloc_node(size_t size, gfp_t gfp, int node)
|
|
{
|
|
return __do_kmalloc_node(size, gfp, node, _RET_IP_);
|
|
}
|
|
EXPORT_SYMBOL(__kmalloc_node);
|
|
|
|
void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node)
|
|
{
|
|
return slob_alloc_node(cachep, gfp, node);
|
|
}
|
|
EXPORT_SYMBOL(kmem_cache_alloc_node);
|
|
#endif
|
|
|
|
static void __kmem_cache_free(void *b, int size)
|
|
{
|
|
if (size < PAGE_SIZE)
|
|
slob_free(b, size);
|
|
else
|
|
slob_free_pages(b, get_order(size));
|
|
}
|
|
|
|
static void kmem_rcu_free(struct rcu_head *head)
|
|
{
|
|
struct slob_rcu *slob_rcu = (struct slob_rcu *)head;
|
|
void *b = (void *)slob_rcu - (slob_rcu->size - sizeof(struct slob_rcu));
|
|
|
|
__kmem_cache_free(b, slob_rcu->size);
|
|
}
|
|
|
|
void kmem_cache_free(struct kmem_cache *c, void *b)
|
|
{
|
|
kmemleak_free_recursive(b, c->flags);
|
|
if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) {
|
|
struct slob_rcu *slob_rcu;
|
|
slob_rcu = b + (c->size - sizeof(struct slob_rcu));
|
|
slob_rcu->size = c->size;
|
|
call_rcu(&slob_rcu->head, kmem_rcu_free);
|
|
} else {
|
|
__kmem_cache_free(b, c->size);
|
|
}
|
|
|
|
trace_kmem_cache_free(_RET_IP_, b);
|
|
}
|
|
EXPORT_SYMBOL(kmem_cache_free);
|
|
|
|
void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p)
|
|
{
|
|
__kmem_cache_free_bulk(s, size, p);
|
|
}
|
|
EXPORT_SYMBOL(kmem_cache_free_bulk);
|
|
|
|
int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
|
|
void **p)
|
|
{
|
|
return __kmem_cache_alloc_bulk(s, flags, size, p);
|
|
}
|
|
EXPORT_SYMBOL(kmem_cache_alloc_bulk);
|
|
|
|
int __kmem_cache_shutdown(struct kmem_cache *c)
|
|
{
|
|
/* No way to check for remaining objects */
|
|
return 0;
|
|
}
|
|
|
|
void __kmem_cache_release(struct kmem_cache *c)
|
|
{
|
|
}
|
|
|
|
int __kmem_cache_shrink(struct kmem_cache *d)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
struct kmem_cache kmem_cache_boot = {
|
|
.name = "kmem_cache",
|
|
.size = sizeof(struct kmem_cache),
|
|
.flags = SLAB_PANIC,
|
|
.align = ARCH_KMALLOC_MINALIGN,
|
|
};
|
|
|
|
void __init kmem_cache_init(void)
|
|
{
|
|
kmem_cache = &kmem_cache_boot;
|
|
slab_state = UP;
|
|
}
|
|
|
|
void __init kmem_cache_init_late(void)
|
|
{
|
|
slab_state = FULL;
|
|
}
|