aboutsummaryrefslogtreecommitdiffstats
path: root/zfs/lib/libumem/vmem_sbrk.c
diff options
context:
space:
mode:
Diffstat (limited to 'zfs/lib/libumem/vmem_sbrk.c')
-rw-r--r--zfs/lib/libumem/vmem_sbrk.c268
1 files changed, 0 insertions, 268 deletions
diff --git a/zfs/lib/libumem/vmem_sbrk.c b/zfs/lib/libumem/vmem_sbrk.c
deleted file mode 100644
index 20bfb7345..000000000
--- a/zfs/lib/libumem/vmem_sbrk.c
+++ /dev/null
@@ -1,268 +0,0 @@
-/*
- * CDDL HEADER START
- *
- * The contents of this file are subject to the terms of the
- * Common Development and Distribution License (the "License").
- * You may not use this file except in compliance with the License.
- *
- * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
- * or http://www.opensolaris.org/os/licensing.
- * See the License for the specific language governing permissions
- * and limitations under the License.
- *
- * When distributing Covered Code, include this CDDL HEADER in each
- * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
- * If applicable, add the following below this CDDL HEADER, with the
- * fields enclosed by brackets "[]" replaced with your own identifying
- * information: Portions Copyright [yyyy] [name of copyright owner]
- *
- * CDDL HEADER END
- */
-
-/*
- * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
- * Use is subject to license terms.
- */
-
-#pragma ident "%Z%%M% %I% %E% SMI"
-
-/*
- * The structure of the sbrk backend:
- *
- * +-----------+
- * | sbrk_top |
- * +-----------+
- * | (vmem_sbrk_alloc(), vmem_free())
- * |
- * +-----------+
- * | sbrk_heap |
- * +-----------+
- * | | ... | (vmem_alloc(), vmem_free())
- * <other arenas>
- *
- * The sbrk_top arena holds all controlled memory. vmem_sbrk_alloc() handles
- * allocations from it, including growing the heap when we run low.
- *
- * Growing the heap is complicated by the fact that we have to extend the
- * sbrk_top arena (using _vmem_extend_alloc()), and that can fail. Since
- * other threads may be actively allocating, we can't return the memory.
- *
- * Instead, we put it on a doubly-linked list, sbrk_fails, which we search
- * before calling sbrk().
- */
-
-#include <errno.h>
-#include <limits.h>
-#include <sys/sysmacros.h>
-#include <sys/mman.h>
-#include <unistd.h>
-
-#include "vmem_base.h"
-
-#include "misc.h"
-
-size_t vmem_sbrk_pagesize = 0; /* the preferred page size of the heap */
-
-#define VMEM_SBRK_MINALLOC (64 * 1024)
-size_t vmem_sbrk_minalloc = VMEM_SBRK_MINALLOC; /* minimum allocation */
-
-static size_t real_pagesize;
-static vmem_t *sbrk_heap;
-
-typedef struct sbrk_fail {
- struct sbrk_fail *sf_next;
- struct sbrk_fail *sf_prev;
- void *sf_base; /* == the sbrk_fail's address */
- size_t sf_size; /* the size of this buffer */
-} sbrk_fail_t;
-
-static sbrk_fail_t sbrk_fails = {
- &sbrk_fails,
- &sbrk_fails,
- NULL,
- 0
-};
-
-static mutex_t sbrk_faillock = DEFAULTMUTEX;
-
-/*
- * Try to extend src with [pos, pos + size).
- *
- * If it fails, add the block to the sbrk_fails list.
- */
-static void *
-vmem_sbrk_extend_alloc(vmem_t *src, void *pos, size_t size, size_t alloc,
- int vmflags)
-{
- sbrk_fail_t *fnext, *fprev, *fp;
- void *ret;
-
- ret = _vmem_extend_alloc(src, pos, size, alloc, vmflags);
- if (ret != NULL)
- return (ret);
-
- fp = (sbrk_fail_t *)pos;
-
- ASSERT(sizeof (sbrk_fail_t) <= size);
-
- fp->sf_base = pos;
- fp->sf_size = size;
-
- (void) mutex_lock(&sbrk_faillock);
- fp->sf_next = fnext = &sbrk_fails;
- fp->sf_prev = fprev = sbrk_fails.sf_prev;
- fnext->sf_prev = fp;
- fprev->sf_next = fp;
- (void) mutex_unlock(&sbrk_faillock);
-
- return (NULL);
-}
-
-/*
- * Try to add at least size bytes to src, using the sbrk_fails list
- */
-static void *
-vmem_sbrk_tryfail(vmem_t *src, size_t size, int vmflags)
-{
- sbrk_fail_t *fp;
-
- (void) mutex_lock(&sbrk_faillock);
- for (fp = sbrk_fails.sf_next; fp != &sbrk_fails; fp = fp->sf_next) {
- if (fp->sf_size >= size) {
- fp->sf_next->sf_prev = fp->sf_prev;
- fp->sf_prev->sf_next = fp->sf_next;
- fp->sf_next = fp->sf_prev = NULL;
- break;
- }
- }
- (void) mutex_unlock(&sbrk_faillock);
-
- if (fp != &sbrk_fails) {
- ASSERT(fp->sf_base == (void *)fp);
- return (vmem_sbrk_extend_alloc(src, fp, fp->sf_size, size,
- vmflags));
- }
- /*
- * nothing of the right size on the freelist
- */
- return (NULL);
-}
-
-static void *
-vmem_sbrk_alloc(vmem_t *src, size_t size, int vmflags)
-{
- extern void *_sbrk_grow_aligned(size_t min_size, size_t low_align,
- size_t high_align, size_t *actual_size);
-
- void *ret;
- void *buf;
- size_t buf_size;
-
- int old_errno = errno;
-
- ret = vmem_alloc(src, size, VM_NOSLEEP);
- if (ret != NULL) {
- errno = old_errno;
- return (ret);
- }
-
- /*
- * The allocation failed. We need to grow the heap.
- *
- * First, try to use any buffers which failed earlier.
- */
- if (sbrk_fails.sf_next != &sbrk_fails &&
- (ret = vmem_sbrk_tryfail(src, size, vmflags)) != NULL)
- return (ret);
-
- buf_size = MAX(size, vmem_sbrk_minalloc);
-
- /*
- * buf_size gets overwritten with the actual allocated size
- */
- buf = _sbrk_grow_aligned(buf_size, real_pagesize, vmem_sbrk_pagesize,
- &buf_size);
-
- if (buf != MAP_FAILED) {
- ret = vmem_sbrk_extend_alloc(src, buf, buf_size, size, vmflags);
- if (ret != NULL) {
- errno = old_errno;
- return (ret);
- }
- }
-
- /*
- * Growing the heap failed. The vmem_alloc() above called umem_reap().
- */
- ASSERT((vmflags & VM_NOSLEEP) == VM_NOSLEEP);
-
- errno = old_errno;
- return (NULL);
-}
-
-/*
- * fork1() support
- */
-void
-vmem_sbrk_lockup(void)
-{
- (void) mutex_lock(&sbrk_faillock);
-}
-
-void
-vmem_sbrk_release(void)
-{
- (void) mutex_unlock(&sbrk_faillock);
-}
-
-vmem_t *
-vmem_sbrk_arena(vmem_alloc_t **a_out, vmem_free_t **f_out)
-{
- if (sbrk_heap == NULL) {
- size_t heap_size;
-
- real_pagesize = sysconf(_SC_PAGESIZE);
-
- heap_size = vmem_sbrk_pagesize;
-
- if (issetugid()) {
- heap_size = 0;
- } else if (heap_size != 0 && !ISP2(heap_size)) {
- heap_size = 0;
- log_message("ignoring bad pagesize: 0x%p\n", heap_size);
- }
- if (heap_size <= real_pagesize) {
- heap_size = real_pagesize;
- } else {
- struct memcntl_mha mha;
- mha.mha_cmd = MHA_MAPSIZE_BSSBRK;
- mha.mha_flags = 0;
- mha.mha_pagesize = heap_size;
-
- if (memcntl(NULL, 0, MC_HAT_ADVISE, (char *)&mha, 0, 0)
- == -1) {
- log_message("unable to set MAPSIZE_BSSBRK to "
- "0x%p\n", heap_size);
- heap_size = real_pagesize;
- }
- }
- vmem_sbrk_pagesize = heap_size;
-
- /* validate vmem_sbrk_minalloc */
- if (vmem_sbrk_minalloc < VMEM_SBRK_MINALLOC)
- vmem_sbrk_minalloc = VMEM_SBRK_MINALLOC;
- vmem_sbrk_minalloc = P2ROUNDUP(vmem_sbrk_minalloc, heap_size);
-
- sbrk_heap = vmem_init("sbrk_top", real_pagesize,
- vmem_sbrk_alloc, vmem_free,
- "sbrk_heap", NULL, 0, real_pagesize,
- vmem_alloc, vmem_free);
- }
-
- if (a_out != NULL)
- *a_out = vmem_alloc;
- if (f_out != NULL)
- *f_out = vmem_free;
-
- return (sbrk_heap);
-}