| /*- |
| * Copyright (c) 2002-2005, 2009 Jeffrey Roberson <jeff@FreeBSD.org> |
| * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org> |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice unmodified, this list of conditions, and the following |
| * disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| * $FreeBSD: src/sys/vm/uma_int.h,v 1.39.2.1.2.1 2009/10/25 01:10:29 kensmith Exp $ |
| * |
| */ |
| |
| /* |
| * This file includes definitions, structures, prototypes, and inlines that |
| * should not be used outside of the actual implementation of UMA. |
| */ |
| |
| /* |
| * Here's a quick description of the relationship between the objects: |
| * |
| * Kegs contain lists of slabs which are stored in either the full bin, empty |
| * bin, or partially allocated bin, to reduce fragmentation. They also contain |
| * the user supplied value for size, which is adjusted for alignment purposes |
| * and rsize is the result of that. The Keg also stores information for |
| * managing a hash of page addresses that maps pages to uma_slab_t structures |
| * for pages that don't have embedded uma_slab_t's. |
| * |
| * The uma_slab_t may be embedded in a UMA_SLAB_SIZE chunk of memory or it may |
| * be allocated off the page from a special slab zone. The free list within a |
| * slab is managed with a linked list of indexes, which are 8 bit values. If |
| * UMA_SLAB_SIZE is defined to be too large I will have to switch to 16bit |
| * values. Currently on alpha you can get 250 or so 32 byte items and on x86 |
| * you can get 250 or so 16byte items. For item sizes that would yield more |
| * than 10% memory waste we potentially allocate a separate uma_slab_t if this |
| * will improve the number of items per slab that will fit. |
| * |
| * Other potential space optimizations are storing the 8bit of linkage in space |
| * wasted between items due to alignment problems. This may yield a much better |
| * memory footprint for certain sizes of objects. Another alternative is to |
| * increase the UMA_SLAB_SIZE, or allow for dynamic slab sizes. I prefer |
| * dynamic slab sizes because we could stick with 8 bit indexes and only use |
| * large slab sizes for zones with a lot of waste per slab. This may create |
| * ineffeciencies in the vm subsystem due to fragmentation in the address space. |
| * |
| * The only really gross cases, with regards to memory waste, are for those |
| * items that are just over half the page size. You can get nearly 50% waste, |
| * so you fall back to the memory footprint of the power of two allocator. I |
| * have looked at memory allocation sizes on many of the machines available to |
| * me, and there does not seem to be an abundance of allocations at this range |
| * so at this time it may not make sense to optimize for it. This can, of |
| * course, be solved with dynamic slab sizes. |
| * |
| * Kegs may serve multiple Zones but by far most of the time they only serve |
| * one. When a Zone is created, a Keg is allocated and setup for it. While |
| * the backing Keg stores slabs, the Zone caches Buckets of items allocated |
| * from the slabs. Each Zone is equipped with an init/fini and ctor/dtor |
| * pair, as well as with its own set of small per-CPU caches, layered above |
| * the Zone's general Bucket cache. |
| * |
| * The PCPU caches are protected by critical sections, and may be accessed |
| * safely only from their associated CPU, while the Zones backed by the same |
| * Keg all share a common Keg lock (to coalesce contention on the backing |
| * slabs). The backing Keg typically only serves one Zone but in the case of |
| * multiple Zones, one of the Zones is considered the Master Zone and all |
| * Zone-related stats from the Keg are done in the Master Zone. For an |
| * example of a Multi-Zone setup, refer to the Mbuf allocation code. |
| */ |
| |
| /* |
| * This is the representation for normal (Non OFFPAGE slab) |
| * |
| * i == item |
| * s == slab pointer |
| * |
| * <---------------- Page (UMA_SLAB_SIZE) ------------------> |
| * ___________________________________________________________ |
| * | _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___________ | |
| * ||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i| |slab header|| |
| * ||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_| |___________|| |
| * |___________________________________________________________| |
| * |
| * |
| * This is an OFFPAGE slab. These can be larger than UMA_SLAB_SIZE. |
| * |
| * ___________________________________________________________ |
| * | _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ | |
| * ||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i| | |
| * ||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_| | |
| * |___________________________________________________________| |
| * ___________ ^ |
| * |slab header| | |
| * |___________|---* |
| * |
| */ |
| |
| #ifndef BSD_VM_UMA_INT_H |
| #define BSD_VM_UMA_INT_H |
| |
| #define UMA_SLAB_SIZE PAGE_SIZE /* How big are our slabs? */ |
| #define UMA_SLAB_MASK (PAGE_SIZE - 1) /* Mask to get back to the page */ |
| #define UMA_SLAB_SHIFT PAGE_SHIFT /* Number of bits PAGE_MASK */ |
| |
| #define UMA_BOOT_PAGES 48 /* Pages allocated for startup */ |
| |
| /* Max waste before going to off page slab management */ |
| #define UMA_MAX_WASTE (UMA_SLAB_SIZE / 10) |
| |
| /* |
| * I doubt there will be many cases where this is exceeded. This is the initial |
| * size of the hash table for uma_slabs that are managed off page. This hash |
| * does expand by powers of two. Currently it doesn't get smaller. |
| */ |
| #define UMA_HASH_SIZE_INIT 32 |
| |
| /* |
| * I should investigate other hashing algorithms. This should yield a low |
| * number of collisions if the pages are relatively contiguous. |
| * |
| * This is the same algorithm that most processor caches use. |
| * |
| * I'm shifting and masking instead of % because it should be faster. |
| */ |
| |
| #define UMA_HASH(h, s) ((((unsigned long)s) >> UMA_SLAB_SHIFT) & \ |
| (h)->uh_hashmask) |
| |
| #define UMA_HASH_INSERT(h, s, mem) \ |
| SLIST_INSERT_HEAD(&(h)->uh_slab_hash[UMA_HASH((h), \ |
| (mem))], (s), us_hlink); |
| #define UMA_HASH_REMOVE(h, s, mem) \ |
| SLIST_REMOVE(&(h)->uh_slab_hash[UMA_HASH((h), \ |
| (mem))], (s), uma_slab, us_hlink); |
| |
| /* Hash table for freed address -> slab translation */ |
| |
| SLIST_HEAD(slabhead, uma_slab); |
| |
| struct uma_hash { |
| struct slabhead *uh_slab_hash; /* Hash table for slabs */ |
| int uh_hashsize; /* Current size of the hash table */ |
| int uh_hashmask; /* Mask used during hashing */ |
| }; |
| |
| /* |
| * Structures for per cpu queues. |
| */ |
| |
| struct uma_bucket { |
| LIST_ENTRY(uma_bucket) ub_link; /* Link into the zone */ |
| int16_t ub_cnt; /* Count of free items. */ |
| int16_t ub_entries; /* Max items. */ |
| void *ub_bucket[]; /* actual allocation storage */ |
| }; |
| |
| typedef struct uma_bucket * uma_bucket_t; |
| |
| struct uma_cache { |
| uma_bucket_t uc_freebucket; /* Bucket we're freeing to */ |
| uma_bucket_t uc_allocbucket; /* Bucket to allocate from */ |
| u_int64_t uc_allocs; /* Count of allocations */ |
| u_int64_t uc_frees; /* Count of frees */ |
| }; |
| |
| typedef struct uma_cache * uma_cache_t; |
| |
| /* |
| * Keg management structure |
| * |
| * TODO: Optimize for cache line size |
| * |
| */ |
| struct uma_keg { |
| LIST_ENTRY(uma_keg) uk_link; /* List of all kegs */ |
| |
| struct mtx uk_lock; /* Lock for the keg */ |
| struct uma_hash uk_hash; |
| void *uk_cond; /*condition*/ |
| |
| char *uk_name; /* Name of creating zone. */ |
| LIST_HEAD(,uma_zone) uk_zones; /* Keg's zones */ |
| LIST_HEAD(,uma_slab) uk_part_slab; /* partially allocated slabs */ |
| LIST_HEAD(,uma_slab) uk_free_slab; /* empty slab list */ |
| LIST_HEAD(,uma_slab) uk_full_slab; /* full slabs */ |
| |
| u_int32_t uk_recurse; /* Allocation recursion count */ |
| u_int32_t uk_align; /* Alignment mask */ |
| u_int32_t uk_pages; /* Total page count */ |
| u_int32_t uk_free; /* Count of items free in slabs */ |
| u_int32_t uk_size; /* Requested size of each item */ |
| u_int32_t uk_rsize; /* Real size of each item */ |
| u_int32_t uk_maxpages; /* Maximum number of pages to alloc */ |
| |
| uma_init uk_init; /* Keg's init routine */ |
| uma_fini uk_fini; /* Keg's fini routine */ |
| uma_alloc uk_allocf; /* Allocation function */ |
| uma_free uk_freef; /* Free routine */ |
| |
| struct vm_object *uk_obj; /* Zone specific object */ |
| vm_offset_t uk_kva; /* Base kva for zones with objs */ |
| uma_zone_t uk_slabzone; /* Slab zone backing us, if OFFPAGE */ |
| |
| u_int16_t uk_pgoff; /* Offset to uma_slab struct */ |
| u_int16_t uk_ppera; /* pages per allocation from backend */ |
| u_int16_t uk_ipers; /* Items per slab */ |
| u_int32_t uk_flags; /* Internal flags */ |
| }; |
| typedef struct uma_keg * uma_keg_t; |
| |
| /* Page management structure */ |
| |
| /* Sorry for the union, but space efficiency is important */ |
| struct uma_slab_head { |
| uma_keg_t us_keg; /* Keg we live in */ |
| union { |
| LIST_ENTRY(uma_slab) _us_link; /* slabs in zone */ |
| unsigned long _us_size; /* Size of allocation */ |
| } us_type; |
| SLIST_ENTRY(uma_slab) us_hlink; /* Link for hash table */ |
| u_int8_t *us_data; /* First item */ |
| u_int8_t us_flags; /* Page flags see uma.h */ |
| u_int8_t us_freecount; /* How many are free? */ |
| u_int8_t us_firstfree; /* First free item index */ |
| }; |
| |
| /* The standard slab structure */ |
| struct uma_slab { |
| struct uma_slab_head us_head; /* slab header data */ |
| struct { |
| u_int8_t us_item; |
| } us_freelist[1]; /* actual number bigger */ |
| }; |
| |
| /* |
| * The slab structure for UMA_ZONE_REFCNT zones for whose items we |
| * maintain reference counters in the slab for. |
| */ |
| struct uma_slab_refcnt { |
| struct uma_slab_head us_head; /* slab header data */ |
| struct { |
| u_int8_t us_item; |
| u_int32_t us_refcnt; |
| } us_freelist[1]; /* actual number bigger */ |
| }; |
| |
| #define us_keg us_head.us_keg |
| #define us_link us_head.us_type._us_link |
| #define us_size us_head.us_type._us_size |
| #define us_hlink us_head.us_hlink |
| #define us_data us_head.us_data |
| #define us_flags us_head.us_flags |
| #define us_freecount us_head.us_freecount |
| #define us_firstfree us_head.us_firstfree |
| |
| typedef struct uma_slab * uma_slab_t; |
| typedef struct uma_slab_refcnt * uma_slabrefcnt_t; |
| typedef uma_slab_t (*uma_slaballoc)(uma_zone_t, uma_keg_t, int); |
| |
| |
| /* |
| * These give us the size of one free item reference within our corresponding |
| * uma_slab structures, so that our calculations during zone setup are correct |
| * regardless of what the compiler decides to do with padding the structure |
| * arrays within uma_slab. |
| */ |
| #define UMA_FRITM_SZ (sizeof(struct uma_slab) - sizeof(struct uma_slab_head)) |
| #define UMA_FRITMREF_SZ (sizeof(struct uma_slab_refcnt) - \ |
| sizeof(struct uma_slab_head)) |
| |
| struct uma_klink { |
| LIST_ENTRY(uma_klink) kl_link; |
| uma_keg_t kl_keg; |
| }; |
| typedef struct uma_klink *uma_klink_t; |
| |
| /* |
| * Zone management structure |
| * |
| * TODO: Optimize for cache line size |
| * |
| */ |
| struct uma_zone { |
| char *uz_name; /* Text name of the zone */ |
| struct mtx *uz_lock; /* Lock for the zone (keg's lock) */ |
| void *uz_cond; /*condition*/ |
| struct mtx uz_critical_lock; /* simulate critical_enter/exit */ |
| |
| LIST_ENTRY(uma_zone) uz_link; /* List of all zones in keg */ |
| LIST_HEAD(,uma_bucket) uz_full_bucket; /* full buckets */ |
| LIST_HEAD(,uma_bucket) uz_free_bucket; /* Buckets for frees */ |
| |
| LIST_HEAD(,uma_klink) uz_kegs; /* List of kegs. */ |
| struct uma_klink uz_klink; /* klink for first keg. */ |
| |
| uma_slaballoc uz_slab; /* Allocate a slab from the backend. */ |
| uma_ctor uz_ctor; /* Constructor for each allocation */ |
| uma_dtor uz_dtor; /* Destructor */ |
| uma_init uz_init; /* Initializer for each item */ |
| uma_fini uz_fini; /* Discards memory */ |
| |
| u_int64_t uz_allocs; /* Total number of allocations */ |
| u_int64_t uz_frees; /* Total number of frees */ |
| u_int64_t uz_fails; /* Total number of alloc failures */ |
| u_int32_t uz_flags; /* Flags inherited from kegs */ |
| u_int32_t uz_size; /* Size inherited from kegs */ |
| uint16_t uz_fills; /* Outstanding bucket fills */ |
| uint16_t uz_count; /* Highest value ub_ptr can have */ |
| |
| /* |
| * This HAS to be the last item because we adjust the zone size |
| * based on NCPU and then allocate the space for the zones. |
| */ |
| struct uma_cache uz_cpu[1]; /* Per cpu caches */ |
| }; |
| |
| /* |
| * These flags must not overlap with the UMA_ZONE flags specified in uma.h. |
| */ |
| #define UMA_ZFLAG_BUCKET 0x02000000 /* Bucket zone. */ |
| #define UMA_ZFLAG_MULTI 0x04000000 /* Multiple kegs in the zone. */ |
| #define UMA_ZFLAG_DRAINING 0x08000000 /* Running zone_drain. */ |
| #define UMA_ZFLAG_PRIVALLOC 0x10000000 /* Use uz_allocf. */ |
| #define UMA_ZFLAG_INTERNAL 0x20000000 /* No offpage no PCPU. */ |
| #define UMA_ZFLAG_FULL 0x40000000 /* Reached uz_maxpages */ |
| #define UMA_ZFLAG_CACHEONLY 0x80000000 /* Don't ask VM for buckets. */ |
| |
| #define UMA_ZFLAG_INHERIT (UMA_ZFLAG_INTERNAL | UMA_ZFLAG_CACHEONLY | \ |
| UMA_ZFLAG_BUCKET) |
| |
| #ifdef _FREEBSD_KERNEL |
| /* Internal prototypes */ |
| static __inline uma_slab_t hash_sfind(struct uma_hash *hash, u_int8_t *data); |
| void *uma_large_malloc(int size, int wait); |
| void uma_large_free(uma_slab_t slab); |
| |
| /* Lock Macros */ |
| |
| #define KEG_LOCK_INIT(k, lc) \ |
| do { \ |
| if ((lc)) \ |
| mtx_init(&(k)->uk_lock, (k)->uk_name, \ |
| (k)->uk_name, MTX_DEF | MTX_DUPOK); \ |
| else \ |
| mtx_init(&(k)->uk_lock, (k)->uk_name, \ |
| "UMA zone", MTX_DEF | MTX_DUPOK); \ |
| } while (0) |
| |
| #define KEG_LOCK_FINI(k) mtx_destroy(&(k)->uk_lock) |
| #define KEG_LOCK(k) mtx_lock(&(k)->uk_lock) |
| #define KEG_UNLOCK(k) mtx_unlock(&(k)->uk_lock) |
| #define ZONE_LOCK(z) mtx_lock((z)->uz_lock) |
| #define ZONE_UNLOCK(z) mtx_unlock((z)->uz_lock) |
| |
| #define ZONE_CRITICAL_LOCK(z) |
| #define ZONE_CRITICAL_UNLOCK(z) |
| #if 0 |
| #define ZONE_CRITICAL_LOCK(z) mtx_lock(&(z)->uz_critical_lock) |
| #define ZONE_CRITICAL_UNLOCK(z) mtx_unlock(&(z)->uz_critical_lock) |
| #endif |
| |
| /* |
| * These are the flags defined for vm_page. |
| * |
| * Note: PG_UNMANAGED (used by OBJT_PHYS) indicates that the page is |
| * not under PV management but otherwise should be treated as a |
| * normal page. Pages not under PV management cannot be paged out |
| * via the object/vm_page_t because there is no knowledge of their |
| * pte mappings, nor can they be removed from their objects via |
| * the object, and such pages are also not on any PQ queue. |
| */ |
| #define PG_CACHED 0x0001 /* page is cached */ |
| #define PG_FREE 0x0002 /* page is free */ |
| #define PG_WINATCFLS 0x0004 /* flush dirty page on inactive q */ |
| #define PG_FICTITIOUS 0x0008 /* physical page doesn't exist (O) */ |
| #define PG_WRITEABLE 0x0010 /* page is mapped writeable */ |
| #define PG_ZERO 0x0040 /* page is zeroed */ |
| #define PG_REFERENCED 0x0080 /* page has been referenced */ |
| #define PG_UNMANAGED 0x0800 /* No PV management for page */ |
| #define PG_MARKER 0x1000 /* special queue marker page */ |
| #define PG_SLAB 0x2000 /* object pointer is actually a slab */ |
| |
| |
| |
| /* |
| * Find a slab within a hash table. This is used for OFFPAGE zones to lookup |
| * the slab structure. |
| * |
| * Arguments: |
| * hash The hash table to search. |
| * data The base page of the item. |
| * |
| * Returns: |
| * A pointer to a slab if successful, else NULL. |
| */ |
| static __inline uma_slab_t |
| hash_sfind(struct uma_hash *hash, u_int8_t *data) |
| { |
| uma_slab_t slab; |
| int hval; |
| |
| hval = UMA_HASH(hash, data); |
| |
| SLIST_FOREACH(slab, &hash->uh_slab_hash[hval], us_hlink) { |
| if ((u_int8_t *)slab->us_data == data) |
| return (slab); |
| } |
| return (NULL); |
| } |
| |
| static __inline uma_slab_t |
| vtoslab(vm_offset_t va) |
| { |
| vm_page_t p; |
| uma_slab_t slab; |
| struct vm_page_list * page_list; |
| unsigned long pfn = va >> PAGE_SHIFT; |
| uint8_t *page_addr = (uint8_t*)(pfn << PAGE_SHIFT); |
| |
| page_list = &page_slab_hash[pfn % MAX_UPTCP_PAGENUM]; |
| |
| SLIST_FOREACH(p, page_list, page_link) { |
| if(p->page_addr == page_addr) |
| break; |
| } |
| |
| if(p != NULL){ |
| slab = (uma_slab_t )p->object; |
| |
| if (p->flags & PG_SLAB) |
| return (slab); |
| else |
| return (NULL); |
| }else { |
| return NULL; |
| } |
| } |
| |
| static __inline void |
| vsetslab(vm_offset_t va, uma_slab_t slab) |
| { |
| vm_page_t p; |
| struct vm_page_list * page_list; |
| unsigned long pfn = va >> PAGE_SHIFT; |
| uint8_t *page_addr = (uint8_t*)(pfn << PAGE_SHIFT); |
| |
| page_list = &page_slab_hash[pfn % MAX_UPTCP_PAGENUM]; |
| |
| SLIST_FOREACH(p, page_list, page_link) { |
| if(p->page_addr == page_addr) |
| break; |
| } |
| |
| if(p != NULL){ |
| p->object = (void*)slab; |
| p->flags |= PG_SLAB; |
| } |
| |
| } |
| |
| #if 0 |
| static __inline void |
| vsetobj(vm_offset_t va, vm_object_t obj) |
| { |
| |
| vm_page_t p; |
| |
| p = PHYS_TO_VM_PAGE(pmap_kextract(va)); |
| p->object = obj; |
| p->flags &= ~PG_SLAB; |
| |
| } |
| #endif //0 |
| |
| /* |
| * The following two functions may be defined by architecture specific code |
| * if they can provide more effecient allocation functions. This is useful |
| * for using direct mapped addresses. |
| */ |
| void *uma_small_alloc(uma_zone_t zone, int bytes, u_int8_t *pflag, int wait); |
| void uma_small_free(void *mem, int size, u_int8_t flags); |
| #endif /* _FREEBSD_KERNEL */ |
| |
| #endif /* BSD_VM_UMA_INT_H */ |
