svn commit: r252330 - in head/sys: conf geom kern sys vm
Adrian Chadd
adrian at freebsd.org
Fri Jun 28 08:29:36 UTC 2013
Hi,
Do we really need another allocator / resource manager just for this?
Adrian
On 27 June 2013 20:51, Jeff Roberson <jeff at freebsd.org> wrote:
> Author: jeff
> Date: Fri Jun 28 03:51:20 2013
> New Revision: 252330
> URL: http://svnweb.freebsd.org/changeset/base/252330
>
> Log:
> - Add a general purpose resource allocator, vmem, from NetBSD. It was
> originally inspired by the Solaris vmem detailed in the proceedings
> of usenix 2001. The NetBSD version was heavily refactored for bugs
> and simplicity.
> - Use this resource allocator to allocate the buffer and transient maps.
> Buffer cache defrags are reduced by 25% when used by filesystems with
> mixed block sizes. Ultimately this may permit dynamic buffer cache
> sizing on low KVA machines.
>
> Discussed with: alc, kib, attilio
> Tested by: pho
> Sponsored by: EMC / Isilon Storage Division
>
> Added:
> head/sys/kern/subr_vmem.c (contents, props changed)
> head/sys/sys/vmem.h (contents, props changed)
> Modified:
> head/sys/conf/files
> head/sys/geom/geom_io.c
> head/sys/kern/vfs_bio.c
> head/sys/sys/malloc.h
> head/sys/vm/vm.h
> head/sys/vm/vm_init.c
> head/sys/vm/vm_kern.c
> head/sys/vm/vm_kern.h
> head/sys/vm/vm_object.c
> head/sys/vm/vm_pager.c
> head/sys/vm/vm_pager.h
>
> Modified: head/sys/conf/files
> ==============================================================================
> --- head/sys/conf/files Fri Jun 28 03:41:23 2013 (r252329)
> +++ head/sys/conf/files Fri Jun 28 03:51:20 2013 (r252330)
> @@ -2797,6 +2797,7 @@ kern/subr_trap.c standard
> kern/subr_turnstile.c standard
> kern/subr_uio.c standard
> kern/subr_unit.c standard
> +kern/subr_vmem.c standard
> kern/subr_witness.c optional witness
> kern/sys_capability.c standard
> kern/sys_generic.c standard
>
> Modified: head/sys/geom/geom_io.c
> ==============================================================================
> --- head/sys/geom/geom_io.c Fri Jun 28 03:41:23 2013 (r252329)
> +++ head/sys/geom/geom_io.c Fri Jun 28 03:51:20 2013 (r252330)
> @@ -49,6 +49,7 @@ __FBSDID("$FreeBSD$");
> #include <sys/proc.h>
> #include <sys/stack.h>
> #include <sys/sysctl.h>
> +#include <sys/vmem.h>
>
> #include <sys/errno.h>
> #include <geom/geom.h>
> @@ -626,7 +627,6 @@ g_io_transient_map_bio(struct bio *bp)
> vm_offset_t addr;
> long size;
> u_int retried;
> - int rv;
>
> KASSERT(unmapped_buf_allowed, ("unmapped disabled"));
>
> @@ -636,10 +636,7 @@ g_io_transient_map_bio(struct bio *bp)
> retried = 0;
> atomic_add_long(&transient_maps, 1);
> retry:
> - vm_map_lock(bio_transient_map);
> - if (vm_map_findspace(bio_transient_map, vm_map_min(bio_transient_map),
> - size, &addr)) {
> - vm_map_unlock(bio_transient_map);
> + if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) {
> if (transient_map_retries != 0 &&
> retried >= transient_map_retries) {
> g_io_deliver(bp, EDEADLK/* XXXKIB */);
> @@ -651,7 +648,7 @@ retry:
> /*
> * Naive attempt to quisce the I/O to get more
> * in-flight requests completed and defragment
> - * the bio_transient_map.
> + * the transient_arena.
> */
> CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d",
> bp, bp->bio_to->name, retried);
> @@ -661,12 +658,6 @@ retry:
> goto retry;
> }
> }
> - rv = vm_map_insert(bio_transient_map, NULL, 0, addr, addr + size,
> - VM_PROT_RW, VM_PROT_RW, MAP_NOFAULT);
> - KASSERT(rv == KERN_SUCCESS,
> - ("vm_map_insert(bio_transient_map) rv %d %jx %lx",
> - rv, (uintmax_t)addr, size));
> - vm_map_unlock(bio_transient_map);
> atomic_add_int(&inflight_transient_maps, 1);
> pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size));
> bp->bio_data = (caddr_t)addr + bp->bio_ma_offset;
>
> Added: head/sys/kern/subr_vmem.c
> ==============================================================================
> --- /dev/null 00:00:00 1970 (empty, because file is newly added)
> +++ head/sys/kern/subr_vmem.c Fri Jun 28 03:51:20 2013 (r252330)
> @@ -0,0 +1,1372 @@
> +/*-
> + * Copyright (c)2006,2007,2008,2009 YAMAMOTO Takashi,
> + * Copyright (c) 2013 EMC Corp.
> + * 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, 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
> + */
> +
> +/*
> + * From:
> + * $NetBSD: vmem_impl.h,v 1.2 2013/01/29 21:26:24 para Exp $
> + * $NetBSD: subr_vmem.c,v 1.83 2013/03/06 11:20:10 yamt Exp $
> + */
> +
> +/*
> + * reference:
> + * - Magazines and Vmem: Extending the Slab Allocator
> + * to Many CPUs and Arbitrary Resources
> + * http://www.usenix.org/event/usenix01/bonwick.html
> + */
> +
> +#include <sys/cdefs.h>
> +__FBSDID("$FreeBSD$");
> +
> +#include "opt_ddb.h"
> +
> +#include <sys/param.h>
> +#include <sys/systm.h>
> +#include <sys/kernel.h>
> +#include <sys/queue.h>
> +#include <sys/callout.h>
> +#include <sys/hash.h>
> +#include <sys/lock.h>
> +#include <sys/malloc.h>
> +#include <sys/mutex.h>
> +#include <sys/smp.h>
> +#include <sys/condvar.h>
> +#include <sys/taskqueue.h>
> +#include <sys/vmem.h>
> +
> +#include <vm/uma.h>
> +#include <vm/vm.h>
> +#include <vm/pmap.h>
> +#include <vm/vm_map.h>
> +#include <vm/vm_kern.h>
> +#include <vm/vm_extern.h>
> +#include <vm/vm_param.h>
> +#include <vm/vm_pageout.h>
> +
> +#define VMEM_MAXORDER (sizeof(vmem_size_t) * NBBY)
> +
> +#define VMEM_HASHSIZE_MIN 16
> +#define VMEM_HASHSIZE_MAX 131072
> +
> +#define VMEM_QCACHE_IDX_MAX 16
> +
> +#define VMEM_FITMASK (M_BESTFIT | M_FIRSTFIT)
> +
> +#define VMEM_FLAGS \
> + (M_NOWAIT | M_WAITOK | M_USE_RESERVE | M_NOVM | M_BESTFIT | M_FIRSTFIT)
> +
> +#define BT_FLAGS (M_NOWAIT | M_WAITOK | M_USE_RESERVE | M_NOVM)
> +
> +#define QC_NAME_MAX 16
> +
> +/*
> + * Data structures private to vmem.
> + */
> +MALLOC_DEFINE(M_VMEM, "vmem", "vmem internal structures");
> +
> +typedef struct vmem_btag bt_t;
> +
> +TAILQ_HEAD(vmem_seglist, vmem_btag);
> +LIST_HEAD(vmem_freelist, vmem_btag);
> +LIST_HEAD(vmem_hashlist, vmem_btag);
> +
> +struct qcache {
> + uma_zone_t qc_cache;
> + vmem_t *qc_vmem;
> + vmem_size_t qc_size;
> + char qc_name[QC_NAME_MAX];
> +};
> +typedef struct qcache qcache_t;
> +#define QC_POOL_TO_QCACHE(pool) ((qcache_t *)(pool->pr_qcache))
> +
> +#define VMEM_NAME_MAX 16
> +
> +/* vmem arena */
> +struct vmem {
> + struct mtx_padalign vm_lock;
> + struct cv vm_cv;
> + char vm_name[VMEM_NAME_MAX+1];
> + LIST_ENTRY(vmem) vm_alllist;
> + struct vmem_hashlist vm_hash0[VMEM_HASHSIZE_MIN];
> + struct vmem_freelist vm_freelist[VMEM_MAXORDER];
> + struct vmem_seglist vm_seglist;
> + struct vmem_hashlist *vm_hashlist;
> + vmem_size_t vm_hashsize;
> +
> + /* Constant after init */
> + vmem_size_t vm_qcache_max;
> + vmem_size_t vm_quantum_mask;
> + vmem_size_t vm_import_quantum;
> + int vm_quantum_shift;
> +
> + /* Written on alloc/free */
> + LIST_HEAD(, vmem_btag) vm_freetags;
> + int vm_nfreetags;
> + int vm_nbusytag;
> + vmem_size_t vm_inuse;
> + vmem_size_t vm_size;
> +
> + /* Used on import. */
> + vmem_import_t *vm_importfn;
> + vmem_release_t *vm_releasefn;
> + void *vm_arg;
> +
> + /* Space exhaustion callback. */
> + vmem_reclaim_t *vm_reclaimfn;
> +
> + /* quantum cache */
> + qcache_t vm_qcache[VMEM_QCACHE_IDX_MAX];
> +};
> +
> +/* boundary tag */
> +struct vmem_btag {
> + TAILQ_ENTRY(vmem_btag) bt_seglist;
> + union {
> + LIST_ENTRY(vmem_btag) u_freelist; /* BT_TYPE_FREE */
> + LIST_ENTRY(vmem_btag) u_hashlist; /* BT_TYPE_BUSY */
> + } bt_u;
> +#define bt_hashlist bt_u.u_hashlist
> +#define bt_freelist bt_u.u_freelist
> + vmem_addr_t bt_start;
> + vmem_size_t bt_size;
> + int bt_type;
> +};
> +
> +#define BT_TYPE_SPAN 1 /* Allocated from importfn */
> +#define BT_TYPE_SPAN_STATIC 2 /* vmem_add() or create. */
> +#define BT_TYPE_FREE 3 /* Available space. */
> +#define BT_TYPE_BUSY 4 /* Used space. */
> +#define BT_ISSPAN_P(bt) ((bt)->bt_type <= BT_TYPE_SPAN_STATIC)
> +
> +#define BT_END(bt) ((bt)->bt_start + (bt)->bt_size - 1)
> +
> +#if defined(DIAGNOSTIC)
> +static void vmem_check(vmem_t *);
> +#endif
> +
> +static struct callout vmem_periodic_ch;
> +static int vmem_periodic_interval;
> +static struct task vmem_periodic_wk;
> +
> +static struct mtx_padalign vmem_list_lock;
> +static LIST_HEAD(, vmem) vmem_list = LIST_HEAD_INITIALIZER(vmem_list);
> +
> +/* ---- misc */
> +#define VMEM_CONDVAR_INIT(vm, wchan) cv_init(&vm->vm_cv, wchan)
> +#define VMEM_CONDVAR_DESTROY(vm) cv_destroy(&vm->vm_cv)
> +#define VMEM_CONDVAR_WAIT(vm) cv_wait(&vm->vm_cv, &vm->vm_lock)
> +#define VMEM_CONDVAR_BROADCAST(vm) cv_broadcast(&vm->vm_cv)
> +
> +
> +#define VMEM_LOCK(vm) mtx_lock(&vm->vm_lock)
> +#define VMEM_TRYLOCK(vm) mtx_trylock(&vm->vm_lock)
> +#define VMEM_UNLOCK(vm) mtx_unlock(&vm->vm_lock)
> +#define VMEM_LOCK_INIT(vm, name) mtx_init(&vm->vm_lock, (name), NULL, MTX_DEF)
> +#define VMEM_LOCK_DESTROY(vm) mtx_destroy(&vm->vm_lock)
> +#define VMEM_ASSERT_LOCKED(vm) mtx_assert(&vm->vm_lock, MA_OWNED);
> +
> +#define VMEM_ALIGNUP(addr, align) (-(-(addr) & -(align)))
> +
> +#define VMEM_CROSS_P(addr1, addr2, boundary) \
> + ((((addr1) ^ (addr2)) & -(boundary)) != 0)
> +
> +#define ORDER2SIZE(order) ((vmem_size_t)1 << (order))
> +#define SIZE2ORDER(size) ((int)flsl(size) - 1)
> +
> +/*
> + * Maximum number of boundary tags that may be required to satisfy an
> + * allocation. Two may be required to import. Another two may be
> + * required to clip edges.
> + */
> +#define BT_MAXALLOC 4
> +
> +/*
> + * Max free limits the number of locally cached boundary tags. We
> + * just want to avoid hitting the zone allocator for every call.
> + */
> +#define BT_MAXFREE (BT_MAXALLOC * 8)
> +
> +/* Allocator for boundary tags. */
> +static uma_zone_t vmem_bt_zone;
> +
> +/* boot time arena storage. */
> +static struct vmem buffer_arena_storage;
> +static struct vmem transient_arena_storage;
> +vmem_t *buffer_arena = &buffer_arena_storage;
> +vmem_t *transient_arena = &transient_arena_storage;
> +
> +/*
> + * Fill the vmem's boundary tag cache. We guarantee that boundary tag
> + * allocation will not fail once bt_fill() passes. To do so we cache
> + * at least the maximum possible tag allocations in the arena.
> + */
> +static int
> +bt_fill(vmem_t *vm, int flags)
> +{
> + bt_t *bt;
> +
> + VMEM_ASSERT_LOCKED(vm);
> +
> + /*
> + * Loop until we meet the reserve. To minimize the lock shuffle
> + * and prevent simultaneous fills we first try a NOWAIT regardless
> + * of the caller's flags. Specify M_NOVM so we don't recurse while
> + * holding a vmem lock.
> + */
> + while (vm->vm_nfreetags < BT_MAXALLOC) {
> + bt = uma_zalloc(vmem_bt_zone,
> + (flags & M_USE_RESERVE) | M_NOWAIT | M_NOVM);
> + if (bt == NULL) {
> + VMEM_UNLOCK(vm);
> + bt = uma_zalloc(vmem_bt_zone, flags);
> + VMEM_LOCK(vm);
> + if (bt == NULL && (flags & M_NOWAIT) != 0)
> + break;
> + }
> + LIST_INSERT_HEAD(&vm->vm_freetags, bt, bt_freelist);
> + vm->vm_nfreetags++;
> + }
> +
> + if (vm->vm_nfreetags < BT_MAXALLOC)
> + return ENOMEM;
> +
> + return 0;
> +}
> +
> +/*
> + * Pop a tag off of the freetag stack.
> + */
> +static bt_t *
> +bt_alloc(vmem_t *vm)
> +{
> + bt_t *bt;
> +
> + VMEM_ASSERT_LOCKED(vm);
> + bt = LIST_FIRST(&vm->vm_freetags);
> + MPASS(bt != NULL);
> + LIST_REMOVE(bt, bt_freelist);
> + vm->vm_nfreetags--;
> +
> + return bt;
> +}
> +
> +/*
> + * Trim the per-vmem free list. Returns with the lock released to
> + * avoid allocator recursions.
> + */
> +static void
> +bt_freetrim(vmem_t *vm, int freelimit)
> +{
> + LIST_HEAD(, vmem_btag) freetags;
> + bt_t *bt;
> +
> + LIST_INIT(&freetags);
> + VMEM_ASSERT_LOCKED(vm);
> + while (vm->vm_nfreetags > freelimit) {
> + bt = LIST_FIRST(&vm->vm_freetags);
> + LIST_REMOVE(bt, bt_freelist);
> + vm->vm_nfreetags--;
> + LIST_INSERT_HEAD(&freetags, bt, bt_freelist);
> + }
> + VMEM_UNLOCK(vm);
> + while ((bt = LIST_FIRST(&freetags)) != NULL) {
> + LIST_REMOVE(bt, bt_freelist);
> + uma_zfree(vmem_bt_zone, bt);
> + }
> +}
> +
> +static inline void
> +bt_free(vmem_t *vm, bt_t *bt)
> +{
> +
> + VMEM_ASSERT_LOCKED(vm);
> + MPASS(LIST_FIRST(&vm->vm_freetags) != bt);
> + LIST_INSERT_HEAD(&vm->vm_freetags, bt, bt_freelist);
> + vm->vm_nfreetags++;
> +}
> +
> +/*
> + * freelist[0] ... [1, 1]
> + * freelist[1] ... [2, 3]
> + * freelist[2] ... [4, 7]
> + * freelist[3] ... [8, 15]
> + * :
> + * freelist[n] ... [(1 << n), (1 << (n + 1)) - 1]
> + * :
> + */
> +
> +static struct vmem_freelist *
> +bt_freehead_tofree(vmem_t *vm, vmem_size_t size)
> +{
> + const vmem_size_t qsize = size >> vm->vm_quantum_shift;
> + const int idx = SIZE2ORDER(qsize);
> +
> + MPASS(size != 0 && qsize != 0);
> + MPASS((size & vm->vm_quantum_mask) == 0);
> + MPASS(idx >= 0);
> + MPASS(idx < VMEM_MAXORDER);
> +
> + return &vm->vm_freelist[idx];
> +}
> +
> +/*
> + * bt_freehead_toalloc: return the freelist for the given size and allocation
> + * strategy.
> + *
> + * For M_FIRSTFIT, return the list in which any blocks are large enough
> + * for the requested size. otherwise, return the list which can have blocks
> + * large enough for the requested size.
> + */
> +static struct vmem_freelist *
> +bt_freehead_toalloc(vmem_t *vm, vmem_size_t size, int strat)
> +{
> + const vmem_size_t qsize = size >> vm->vm_quantum_shift;
> + int idx = SIZE2ORDER(qsize);
> +
> + MPASS(size != 0 && qsize != 0);
> + MPASS((size & vm->vm_quantum_mask) == 0);
> +
> + if (strat == M_FIRSTFIT && ORDER2SIZE(idx) != qsize) {
> + idx++;
> + /* check too large request? */
> + }
> + MPASS(idx >= 0);
> + MPASS(idx < VMEM_MAXORDER);
> +
> + return &vm->vm_freelist[idx];
> +}
> +
> +/* ---- boundary tag hash */
> +
> +static struct vmem_hashlist *
> +bt_hashhead(vmem_t *vm, vmem_addr_t addr)
> +{
> + struct vmem_hashlist *list;
> + unsigned int hash;
> +
> + hash = hash32_buf(&addr, sizeof(addr), 0);
> + list = &vm->vm_hashlist[hash % vm->vm_hashsize];
> +
> + return list;
> +}
> +
> +static bt_t *
> +bt_lookupbusy(vmem_t *vm, vmem_addr_t addr)
> +{
> + struct vmem_hashlist *list;
> + bt_t *bt;
> +
> + VMEM_ASSERT_LOCKED(vm);
> + list = bt_hashhead(vm, addr);
> + LIST_FOREACH(bt, list, bt_hashlist) {
> + if (bt->bt_start == addr) {
> + break;
> + }
> + }
> +
> + return bt;
> +}
> +
> +static void
> +bt_rembusy(vmem_t *vm, bt_t *bt)
> +{
> +
> + VMEM_ASSERT_LOCKED(vm);
> + MPASS(vm->vm_nbusytag > 0);
> + vm->vm_inuse -= bt->bt_size;
> + vm->vm_nbusytag--;
> + LIST_REMOVE(bt, bt_hashlist);
> +}
> +
> +static void
> +bt_insbusy(vmem_t *vm, bt_t *bt)
> +{
> + struct vmem_hashlist *list;
> +
> + VMEM_ASSERT_LOCKED(vm);
> + MPASS(bt->bt_type == BT_TYPE_BUSY);
> +
> + list = bt_hashhead(vm, bt->bt_start);
> + LIST_INSERT_HEAD(list, bt, bt_hashlist);
> + vm->vm_nbusytag++;
> + vm->vm_inuse += bt->bt_size;
> +}
> +
> +/* ---- boundary tag list */
> +
> +static void
> +bt_remseg(vmem_t *vm, bt_t *bt)
> +{
> +
> + TAILQ_REMOVE(&vm->vm_seglist, bt, bt_seglist);
> + bt_free(vm, bt);
> +}
> +
> +static void
> +bt_insseg(vmem_t *vm, bt_t *bt, bt_t *prev)
> +{
> +
> + TAILQ_INSERT_AFTER(&vm->vm_seglist, prev, bt, bt_seglist);
> +}
> +
> +static void
> +bt_insseg_tail(vmem_t *vm, bt_t *bt)
> +{
> +
> + TAILQ_INSERT_TAIL(&vm->vm_seglist, bt, bt_seglist);
> +}
> +
> +static void
> +bt_remfree(vmem_t *vm, bt_t *bt)
> +{
> +
> + MPASS(bt->bt_type == BT_TYPE_FREE);
> +
> + LIST_REMOVE(bt, bt_freelist);
> +}
> +
> +static void
> +bt_insfree(vmem_t *vm, bt_t *bt)
> +{
> + struct vmem_freelist *list;
> +
> + list = bt_freehead_tofree(vm, bt->bt_size);
> + LIST_INSERT_HEAD(list, bt, bt_freelist);
> +}
> +
> +/* ---- vmem internal functions */
> +
> +/*
> + * Import from the arena into the quantum cache in UMA.
> + */
> +static int
> +qc_import(void *arg, void **store, int cnt, int flags)
> +{
> + qcache_t *qc;
> + vmem_addr_t addr;
> + int i;
> +
> + qc = arg;
> + flags |= M_BESTFIT;
> + for (i = 0; i < cnt; i++) {
> + if (vmem_xalloc(qc->qc_vmem, qc->qc_size, 0, 0, 0,
> + VMEM_ADDR_MIN, VMEM_ADDR_MAX, flags, &addr) != 0)
> + break;
> + store[i] = (void *)addr;
> + /* Only guarantee one allocation. */
> + flags &= ~M_WAITOK;
> + flags |= M_NOWAIT;
> + }
> + return i;
> +}
> +
> +/*
> + * Release memory from the UMA cache to the arena.
> + */
> +static void
> +qc_release(void *arg, void **store, int cnt)
> +{
> + qcache_t *qc;
> + int i;
> +
> + qc = arg;
> + for (i = 0; i < cnt; i++)
> + vmem_xfree(qc->qc_vmem, (vmem_addr_t)store[i], qc->qc_size);
> +}
> +
> +static void
> +qc_init(vmem_t *vm, vmem_size_t qcache_max)
> +{
> + qcache_t *qc;
> + vmem_size_t size;
> + int qcache_idx_max;
> + int i;
> +
> + MPASS((qcache_max & vm->vm_quantum_mask) == 0);
> + qcache_idx_max = MIN(qcache_max >> vm->vm_quantum_shift,
> + VMEM_QCACHE_IDX_MAX);
> + vm->vm_qcache_max = qcache_idx_max << vm->vm_quantum_shift;
> + for (i = 0; i < qcache_idx_max; i++) {
> + qc = &vm->vm_qcache[i];
> + size = (i + 1) << vm->vm_quantum_shift;
> + snprintf(qc->qc_name, sizeof(qc->qc_name), "%s-%zu",
> + vm->vm_name, size);
> + qc->qc_vmem = vm;
> + qc->qc_size = size;
> + qc->qc_cache = uma_zcache_create(qc->qc_name, size,
> + NULL, NULL, NULL, NULL, qc_import, qc_release, qc,
> + UMA_ZONE_VM);
> + MPASS(qc->qc_cache);
> + }
> +}
> +
> +static void
> +qc_destroy(vmem_t *vm)
> +{
> + int qcache_idx_max;
> + int i;
> +
> + qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift;
> + for (i = 0; i < qcache_idx_max; i++)
> + uma_zdestroy(vm->vm_qcache[i].qc_cache);
> +}
> +
> +static void
> +qc_drain(vmem_t *vm)
> +{
> + int qcache_idx_max;
> + int i;
> +
> + qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift;
> + for (i = 0; i < qcache_idx_max; i++)
> + zone_drain(vm->vm_qcache[i].qc_cache);
> +}
> +
> +void
> +vmem_startup(void)
> +{
> +
> + mtx_init(&vmem_list_lock, "vmem list lock", NULL, MTX_DEF);
> + vmem_bt_zone = uma_zcreate("vmem btag",
> + sizeof(struct vmem_btag), NULL, NULL, NULL, NULL,
> + UMA_ALIGN_PTR, UMA_ZONE_VM);
> +}
> +
> +/* ---- rehash */
> +
> +static int
> +vmem_rehash(vmem_t *vm, vmem_size_t newhashsize)
> +{
> + bt_t *bt;
> + int i;
> + struct vmem_hashlist *newhashlist;
> + struct vmem_hashlist *oldhashlist;
> + vmem_size_t oldhashsize;
> +
> + MPASS(newhashsize > 0);
> +
> + newhashlist = malloc(sizeof(struct vmem_hashlist) * newhashsize,
> + M_VMEM, M_NOWAIT);
> + if (newhashlist == NULL)
> + return ENOMEM;
> + for (i = 0; i < newhashsize; i++) {
> + LIST_INIT(&newhashlist[i]);
> + }
> +
> + VMEM_LOCK(vm);
> + oldhashlist = vm->vm_hashlist;
> + oldhashsize = vm->vm_hashsize;
> + vm->vm_hashlist = newhashlist;
> + vm->vm_hashsize = newhashsize;
> + if (oldhashlist == NULL) {
> + VMEM_UNLOCK(vm);
> + return 0;
> + }
> + for (i = 0; i < oldhashsize; i++) {
> + while ((bt = LIST_FIRST(&oldhashlist[i])) != NULL) {
> + bt_rembusy(vm, bt);
> + bt_insbusy(vm, bt);
> + }
> + }
> + VMEM_UNLOCK(vm);
> +
> + if (oldhashlist != vm->vm_hash0) {
> + free(oldhashlist, M_VMEM);
> + }
> +
> + return 0;
> +}
> +
> +static void
> +vmem_periodic_kick(void *dummy)
> +{
> +
> + taskqueue_enqueue(taskqueue_thread, &vmem_periodic_wk);
> +}
> +
> +static void
> +vmem_periodic(void *unused, int pending)
> +{
> + vmem_t *vm;
> + vmem_size_t desired;
> + vmem_size_t current;
> +
> + mtx_lock(&vmem_list_lock);
> + LIST_FOREACH(vm, &vmem_list, vm_alllist) {
> +#ifdef DIAGNOSTIC
> + /* Convenient time to verify vmem state. */
> + VMEM_LOCK(vm);
> + vmem_check(vm);
> + VMEM_UNLOCK(vm);
> +#endif
> + desired = 1 << flsl(vm->vm_nbusytag);
> + desired = MIN(MAX(desired, VMEM_HASHSIZE_MIN),
> + VMEM_HASHSIZE_MAX);
> + current = vm->vm_hashsize;
> +
> + /* Grow in powers of two. Shrink less aggressively. */
> + if (desired >= current * 2 || desired * 4 <= current)
> + vmem_rehash(vm, desired);
> + }
> + mtx_unlock(&vmem_list_lock);
> +
> + callout_reset(&vmem_periodic_ch, vmem_periodic_interval,
> + vmem_periodic_kick, NULL);
> +}
> +
> +static void
> +vmem_start_callout(void *unused)
> +{
> +
> + TASK_INIT(&vmem_periodic_wk, 0, vmem_periodic, NULL);
> + vmem_periodic_interval = hz * 10;
> + callout_init(&vmem_periodic_ch, CALLOUT_MPSAFE);
> + callout_reset(&vmem_periodic_ch, vmem_periodic_interval,
> + vmem_periodic_kick, NULL);
> +}
> +SYSINIT(vfs, SI_SUB_CONFIGURE, SI_ORDER_ANY, vmem_start_callout, NULL);
> +
> +static void
> +vmem_add1(vmem_t *vm, vmem_addr_t addr, vmem_size_t size, int flags, int type)
> +{
> + bt_t *btspan;
> + bt_t *btfree;
> +
> + MPASS(type == BT_TYPE_SPAN || type == BT_TYPE_SPAN_STATIC);
> +
> + btspan = bt_alloc(vm);
> + btspan->bt_type = type;
> + btspan->bt_start = addr;
> + btspan->bt_size = size;
> +
> + btfree = bt_alloc(vm);
> + btfree->bt_type = BT_TYPE_FREE;
> + btfree->bt_start = addr;
> + btfree->bt_size = size;
> +
> + bt_insseg_tail(vm, btspan);
> + bt_insseg(vm, btfree, btspan);
> + bt_insfree(vm, btfree);
> + vm->vm_size += size;
> +}
> +
> +static void
> +vmem_destroy1(vmem_t *vm)
> +{
> + bt_t *bt;
> +
> + /*
> + * Drain per-cpu quantum caches.
> + */
> + qc_destroy(vm);
> +
> + /*
> + * The vmem should now only contain empty segments.
> + */
> + VMEM_LOCK(vm);
> + MPASS(vm->vm_nbusytag == 0);
> +
> + while ((bt = TAILQ_FIRST(&vm->vm_seglist)) != NULL)
> + bt_remseg(vm, bt);
> +
> + if (vm->vm_hashlist != NULL && vm->vm_hashlist != vm->vm_hash0)
> + free(vm->vm_hashlist, M_VMEM);
> +
> + bt_freetrim(vm, 0);
> +
> + VMEM_CONDVAR_DESTROY(vm);
> + VMEM_LOCK_DESTROY(vm);
> + free(vm, M_VMEM);
> +}
> +
> +static int
> +vmem_import(vmem_t *vm, vmem_size_t size, int flags)
> +{
> + vmem_addr_t addr;
> + int error;
> +
> + if (vm->vm_importfn == NULL)
> + return EINVAL;
> +
> + size = roundup(size, vm->vm_import_quantum);
> +
> + /*
> + * Hide MAXALLOC tags so we're guaranteed to be able to add this
> + * span and the tag we want to allocate from it.
> + */
> + MPASS(vm->vm_nfreetags >= BT_MAXALLOC);
> + vm->vm_nfreetags -= BT_MAXALLOC;
> + VMEM_UNLOCK(vm);
> + error = (vm->vm_importfn)(vm->vm_arg, size, flags, &addr);
> + VMEM_LOCK(vm);
> + vm->vm_nfreetags += BT_MAXALLOC;
> + if (error)
> + return ENOMEM;
> +
> + vmem_add1(vm, addr, size, flags, BT_TYPE_SPAN);
> +
> + return 0;
> +}
> +
> +/*
> + * vmem_fit: check if a bt can satisfy the given restrictions.
> + *
> + * it's a caller's responsibility to ensure the region is big enough
> + * before calling us.
> + */
> +static int
> +vmem_fit(const bt_t *bt, vmem_size_t size, vmem_size_t align,
> + vmem_size_t phase, vmem_size_t nocross, vmem_addr_t minaddr,
> + vmem_addr_t maxaddr, vmem_addr_t *addrp)
> +{
> + vmem_addr_t start;
> + vmem_addr_t end;
> +
> + MPASS(size > 0);
> + MPASS(bt->bt_size >= size); /* caller's responsibility */
> +
> + /*
> + * XXX assumption: vmem_addr_t and vmem_size_t are
> + * unsigned integer of the same size.
> + */
> +
> + start = bt->bt_start;
> + if (start < minaddr) {
> + start = minaddr;
> + }
> + end = BT_END(bt);
> + if (end > maxaddr)
> + end = maxaddr;
> + if (start > end)
> + return (ENOMEM);
> +
> + start = VMEM_ALIGNUP(start - phase, align) + phase;
> + if (start < bt->bt_start)
> + start += align;
> + if (VMEM_CROSS_P(start, start + size - 1, nocross)) {
> + MPASS(align < nocross);
> + start = VMEM_ALIGNUP(start - phase, nocross) + phase;
> + }
> + if (start <= end && end - start >= size - 1) {
> + MPASS((start & (align - 1)) == phase);
> + MPASS(!VMEM_CROSS_P(start, start + size - 1, nocross));
> + MPASS(minaddr <= start);
> + MPASS(maxaddr == 0 || start + size - 1 <= maxaddr);
> + MPASS(bt->bt_start <= start);
> + MPASS(BT_END(bt) - start >= size - 1);
> + *addrp = start;
> +
> + return (0);
> + }
> + return (ENOMEM);
> +}
> +
> +/*
> + * vmem_clip: Trim the boundary tag edges to the requested start and size.
> + */
> +static void
> +vmem_clip(vmem_t *vm, bt_t *bt, vmem_addr_t start, vmem_size_t size)
> +{
> + bt_t *btnew;
> + bt_t *btprev;
> +
> + VMEM_ASSERT_LOCKED(vm);
> + MPASS(bt->bt_type == BT_TYPE_FREE);
> + MPASS(bt->bt_size >= size);
> + bt_remfree(vm, bt);
> + if (bt->bt_start != start) {
> + btprev = bt_alloc(vm);
> + btprev->bt_type = BT_TYPE_FREE;
> + btprev->bt_start = bt->bt_start;
> + btprev->bt_size = start - bt->bt_start;
> + bt->bt_start = start;
> + bt->bt_size -= btprev->bt_size;
> + bt_insfree(vm, btprev);
> + bt_insseg(vm, btprev,
> + TAILQ_PREV(bt, vmem_seglist, bt_seglist));
> + }
> + MPASS(bt->bt_start == start);
> + if (bt->bt_size != size && bt->bt_size - size > vm->vm_quantum_mask) {
> + /* split */
> + btnew = bt_alloc(vm);
> + btnew->bt_type = BT_TYPE_BUSY;
> + btnew->bt_start = bt->bt_start;
> + btnew->bt_size = size;
> + bt->bt_start = bt->bt_start + size;
> + bt->bt_size -= size;
> + bt_insfree(vm, bt);
> + bt_insseg(vm, btnew,
> + TAILQ_PREV(bt, vmem_seglist, bt_seglist));
> + bt_insbusy(vm, btnew);
> + bt = btnew;
> + } else {
> + bt->bt_type = BT_TYPE_BUSY;
> + bt_insbusy(vm, bt);
> + }
> + MPASS(bt->bt_size >= size);
> + bt->bt_type = BT_TYPE_BUSY;
> +}
> +
> +/* ---- vmem API */
> +
> +void
> +vmem_set_import(vmem_t *vm, vmem_import_t *importfn,
> + vmem_release_t *releasefn, void *arg, vmem_size_t import_quantum)
> +{
> +
> + VMEM_LOCK(vm);
> + vm->vm_importfn = importfn;
> + vm->vm_releasefn = releasefn;
> + vm->vm_arg = arg;
> + vm->vm_import_quantum = import_quantum;
> + VMEM_UNLOCK(vm);
> +}
> +
> +void
> +vmem_set_reclaim(vmem_t *vm, vmem_reclaim_t *reclaimfn)
> +{
> +
> + VMEM_LOCK(vm);
> + vm->vm_reclaimfn = reclaimfn;
> + VMEM_UNLOCK(vm);
> +}
> +
> +/*
> + * vmem_init: Initializes vmem arena.
> + */
> +vmem_t *
> +vmem_init(vmem_t *vm, const char *name, vmem_addr_t base, vmem_size_t size,
> + vmem_size_t quantum, vmem_size_t qcache_max, int flags)
> +{
> + int i;
> +
> + MPASS(quantum > 0);
> +
> + bzero(vm, sizeof(*vm));
> +
> + VMEM_CONDVAR_INIT(vm, name);
> + VMEM_LOCK_INIT(vm, name);
> + vm->vm_nfreetags = 0;
> + LIST_INIT(&vm->vm_freetags);
> + strlcpy(vm->vm_name, name, sizeof(vm->vm_name));
> + vm->vm_quantum_mask = quantum - 1;
> + vm->vm_quantum_shift = SIZE2ORDER(quantum);
> + MPASS(ORDER2SIZE(vm->vm_quantum_shift) == quantum);
> + vm->vm_nbusytag = 0;
> + vm->vm_size = 0;
> + vm->vm_inuse = 0;
> + qc_init(vm, qcache_max);
> +
> + TAILQ_INIT(&vm->vm_seglist);
> + for (i = 0; i < VMEM_MAXORDER; i++) {
> + LIST_INIT(&vm->vm_freelist[i]);
> + }
> + memset(&vm->vm_hash0, 0, sizeof(vm->vm_hash0));
> + vm->vm_hashsize = VMEM_HASHSIZE_MIN;
> + vm->vm_hashlist = vm->vm_hash0;
> +
> + if (size != 0) {
> + if (vmem_add(vm, base, size, flags) != 0) {
> + vmem_destroy1(vm);
> + return NULL;
> + }
> + }
> +
> + mtx_lock(&vmem_list_lock);
> + LIST_INSERT_HEAD(&vmem_list, vm, vm_alllist);
> + mtx_unlock(&vmem_list_lock);
> +
> + return vm;
> +}
> +
> +/*
> + * vmem_create: create an arena.
> + */
> +vmem_t *
> +vmem_create(const char *name, vmem_addr_t base, vmem_size_t size,
> + vmem_size_t quantum, vmem_size_t qcache_max, int flags)
> +{
> +
> + vmem_t *vm;
> +
> + vm = malloc(sizeof(*vm), M_VMEM, flags & (M_WAITOK|M_NOWAIT));
> + if (vm == NULL)
> + return (NULL);
> + if (vmem_init(vm, name, base, size, quantum, qcache_max,
> + flags) == NULL) {
> + free(vm, M_VMEM);
> + return (NULL);
> + }
> + return (vm);
> +}
> +
> +void
> +vmem_destroy(vmem_t *vm)
> +{
> +
> + mtx_lock(&vmem_list_lock);
> + LIST_REMOVE(vm, vm_alllist);
> + mtx_unlock(&vmem_list_lock);
> +
> + vmem_destroy1(vm);
> +}
>
> *** DIFF OUTPUT TRUNCATED AT 1000 LINES ***
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