Index: stable/11/sys/kern/subr_blist.c =================================================================== --- stable/11/sys/kern/subr_blist.c (revision 324129) +++ stable/11/sys/kern/subr_blist.c (revision 324130) @@ -1,1069 +1,1071 @@ /*- * Copyright (c) 1998 Matthew Dillon. 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. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * 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. */ /* * BLIST.C - Bitmap allocator/deallocator, using a radix tree with hinting * * This module implements a general bitmap allocator/deallocator. The * allocator eats around 2 bits per 'block'. The module does not * try to interpret the meaning of a 'block' other than to return * SWAPBLK_NONE on an allocation failure. * * A radix tree is used to maintain the bitmap. Two radix constants are * involved: One for the bitmaps contained in the leaf nodes (typically * 64), and one for the meta nodes (typically 16). Both meta and leaf * nodes have a hint field. This field gives us a hint as to the largest * free contiguous range of blocks under the node. It may contain a * value that is too high, but will never contain a value that is too * low. When the radix tree is searched, allocation failures in subtrees * update the hint. * * The radix tree also implements two collapsed states for meta nodes: * the ALL-ALLOCATED state and the ALL-FREE state. If a meta node is * in either of these two states, all information contained underneath * the node is considered stale. These states are used to optimize * allocation and freeing operations. * * The hinting greatly increases code efficiency for allocations while * the general radix structure optimizes both allocations and frees. The * radix tree should be able to operate well no matter how much * fragmentation there is and no matter how large a bitmap is used. * * The blist code wires all necessary memory at creation time. Neither * allocations nor frees require interaction with the memory subsystem. * The non-blocking features of the blist code are used in the swap code * (vm/swap_pager.c). * * LAYOUT: The radix tree is laid out recursively using a * linear array. Each meta node is immediately followed (laid out * sequentially in memory) by BLIST_META_RADIX lower level nodes. This * is a recursive structure but one that can be easily scanned through * a very simple 'skip' calculation. In order to support large radixes, * portions of the tree may reside outside our memory allocation. We * handle this with an early-termination optimization (when bighint is * set to -1) on the scan. The memory allocation is only large enough * to cover the number of blocks requested at creation time even if it * must be encompassed in larger root-node radix. * * NOTE: the allocator cannot currently allocate more than * BLIST_BMAP_RADIX blocks per call. It will panic with 'allocation too * large' if you try. This is an area that could use improvement. The * radix is large enough that this restriction does not effect the swap * system, though. Currently only the allocation code is affected by * this algorithmic unfeature. The freeing code can handle arbitrary * ranges. * * This code can be compiled stand-alone for debugging. */ #include __FBSDID("$FreeBSD$"); #ifdef _KERNEL #include #include #include #include #include #include #include #include #else #ifndef BLIST_NO_DEBUG #define BLIST_DEBUG #endif #include #include #include #include #include #include #include #define bitcount64(x) __bitcount64((uint64_t)(x)) #define malloc(a,b,c) calloc(a, 1) #define free(a,b) free(a) #define CTASSERT(expr) #include void panic(const char *ctl, ...); #endif /* * static support functions */ static daddr_t blst_leaf_alloc(blmeta_t *scan, daddr_t blk, int count, daddr_t cursor); -static daddr_t blst_meta_alloc(blmeta_t *scan, daddr_t blk, daddr_t count, - daddr_t radix, daddr_t cursor); +static daddr_t blst_meta_alloc(blmeta_t *scan, daddr_t cursor, daddr_t count, + u_daddr_t radix); static void blst_leaf_free(blmeta_t *scan, daddr_t relblk, int count); static void blst_meta_free(blmeta_t *scan, daddr_t freeBlk, daddr_t count, - daddr_t radix, daddr_t blk); + u_daddr_t radix); static void blst_copy(blmeta_t *scan, daddr_t blk, daddr_t radix, blist_t dest, daddr_t count); static daddr_t blst_leaf_fill(blmeta_t *scan, daddr_t blk, int count); static daddr_t blst_meta_fill(blmeta_t *scan, daddr_t allocBlk, daddr_t count, - daddr_t radix, daddr_t blk); + u_daddr_t radix); static daddr_t blst_radix_init(blmeta_t *scan, daddr_t radix, daddr_t count); #ifndef _KERNEL static void blst_radix_print(blmeta_t *scan, daddr_t blk, daddr_t radix, int tab); #endif #ifdef _KERNEL static MALLOC_DEFINE(M_SWAP, "SWAP", "Swap space"); #endif CTASSERT(BLIST_BMAP_RADIX % BLIST_META_RADIX == 0); /* * For a subtree that can represent the state of up to 'radix' blocks, the * number of leaf nodes of the subtree is L=radix/BLIST_BMAP_RADIX. If 'm' * is short for BLIST_META_RADIX, then for a tree of height h with L=m**h * leaf nodes, the total number of tree nodes is 1 + m + m**2 + ... + m**h, * or, equivalently, (m**(h+1)-1)/(m-1). This quantity is called 'skip' * in the 'meta' functions that process subtrees. Since integer division * discards remainders, we can express this computation as * skip = (m * m**h) / (m - 1) * skip = (m * (radix / BLIST_BMAP_RADIX)) / (m - 1) * and since m divides BLIST_BMAP_RADIX, we can simplify further to * skip = (radix / (BLIST_BMAP_RADIX / m)) / (m - 1) * skip = radix / ((BLIST_BMAP_RADIX / m) * (m - 1)) * so that simple integer division by a constant can safely be used for the * calculation. */ static inline daddr_t radix_to_skip(daddr_t radix) { return (radix / ((BLIST_BMAP_RADIX / BLIST_META_RADIX) * (BLIST_META_RADIX - 1))); } /* * blist_create() - create a blist capable of handling up to the specified * number of blocks * * blocks - must be greater than 0 * flags - malloc flags * * The smallest blist consists of a single leaf node capable of * managing BLIST_BMAP_RADIX blocks. */ blist_t blist_create(daddr_t blocks, int flags) { blist_t bl; daddr_t nodes, radix; /* * Calculate the radix field used for scanning. */ radix = BLIST_BMAP_RADIX; while (radix < blocks) { radix *= BLIST_META_RADIX; } nodes = 1 + blst_radix_init(NULL, radix, blocks); bl = malloc(sizeof(struct blist), M_SWAP, flags); if (bl == NULL) return (NULL); bl->bl_blocks = blocks; bl->bl_radix = radix; bl->bl_cursor = 0; bl->bl_root = malloc(nodes * sizeof(blmeta_t), M_SWAP, flags); if (bl->bl_root == NULL) { free(bl, M_SWAP); return (NULL); } blst_radix_init(bl->bl_root, radix, blocks); #if defined(BLIST_DEBUG) printf( "BLIST representing %lld blocks (%lld MB of swap)" ", requiring %lldK of ram\n", (long long)bl->bl_blocks, (long long)bl->bl_blocks * 4 / 1024, (long long)(nodes * sizeof(blmeta_t) + 1023) / 1024 ); printf("BLIST raw radix tree contains %lld records\n", (long long)nodes); #endif return (bl); } void blist_destroy(blist_t bl) { free(bl->bl_root, M_SWAP); free(bl, M_SWAP); } /* * blist_alloc() - reserve space in the block bitmap. Return the base * of a contiguous region or SWAPBLK_NONE if space could * not be allocated. */ daddr_t blist_alloc(blist_t bl, daddr_t count) { daddr_t blk; /* * This loop iterates at most twice. An allocation failure in the * first iteration leads to a second iteration only if the cursor was * non-zero. When the cursor is zero, an allocation failure will * reduce the hint, stopping further iterations. */ while (count <= bl->bl_root->bm_bighint) { - blk = blst_meta_alloc(bl->bl_root, 0, count, bl->bl_radix, - bl->bl_cursor); + blk = blst_meta_alloc(bl->bl_root, bl->bl_cursor, count, + bl->bl_radix); if (blk != SWAPBLK_NONE) { bl->bl_cursor = blk + count; + if (bl->bl_cursor == bl->bl_blocks) + bl->bl_cursor = 0; return (blk); } else if (bl->bl_cursor != 0) bl->bl_cursor = 0; } return (SWAPBLK_NONE); } /* * blist_avail() - return the number of free blocks. */ daddr_t blist_avail(blist_t bl) { if (bl->bl_radix == BLIST_BMAP_RADIX) return (bitcount64(bl->bl_root->u.bmu_bitmap)); else return (bl->bl_root->u.bmu_avail); } /* * blist_free() - free up space in the block bitmap. Return the base * of a contiguous region. Panic if an inconsistancy is * found. */ void blist_free(blist_t bl, daddr_t blkno, daddr_t count) { - blst_meta_free(bl->bl_root, blkno, count, bl->bl_radix, 0); + blst_meta_free(bl->bl_root, blkno, count, bl->bl_radix); } /* * blist_fill() - mark a region in the block bitmap as off-limits * to the allocator (i.e. allocate it), ignoring any * existing allocations. Return the number of blocks * actually filled that were free before the call. */ daddr_t blist_fill(blist_t bl, daddr_t blkno, daddr_t count) { - return (blst_meta_fill(bl->bl_root, blkno, count, bl->bl_radix, 0)); + return (blst_meta_fill(bl->bl_root, blkno, count, bl->bl_radix)); } /* * blist_resize() - resize an existing radix tree to handle the * specified number of blocks. This will reallocate * the tree and transfer the previous bitmap to the new * one. When extending the tree you can specify whether * the new blocks are to left allocated or freed. */ void blist_resize(blist_t *pbl, daddr_t count, int freenew, int flags) { blist_t newbl = blist_create(count, flags); blist_t save = *pbl; *pbl = newbl; if (count > save->bl_blocks) count = save->bl_blocks; blst_copy(save->bl_root, 0, save->bl_radix, newbl, count); /* * If resizing upwards, should we free the new space or not? */ if (freenew && count < newbl->bl_blocks) { blist_free(newbl, count, newbl->bl_blocks - count); } blist_destroy(save); } #ifdef BLIST_DEBUG /* * blist_print() - dump radix tree */ void blist_print(blist_t bl) { printf("BLIST cursor = %08jx {\n", (uintmax_t)bl->bl_cursor); blst_radix_print(bl->bl_root, 0, bl->bl_radix, 4); printf("}\n"); } #endif /************************************************************************ * ALLOCATION SUPPORT FUNCTIONS * ************************************************************************ * * These support functions do all the actual work. They may seem * rather longish, but that's because I've commented them up. The * actual code is straight forward. * */ /* * blist_leaf_alloc() - allocate at a leaf in the radix tree (a bitmap). * * This is the core of the allocator and is optimized for the * BLIST_BMAP_RADIX block allocation case. Otherwise, execution * time is proportional to log2(count) + log2(BLIST_BMAP_RADIX). */ static daddr_t blst_leaf_alloc(blmeta_t *scan, daddr_t blk, int count, daddr_t cursor) { u_daddr_t mask; int count1, hi, lo, mid, num_shifts, range1, range_ext; if (count == BLIST_BMAP_RADIX) { /* * Optimize allocation of BLIST_BMAP_RADIX bits. If this wasn't * a special case, then forming the final value of 'mask' below * would require special handling to avoid an invalid left shift * when count equals the number of bits in mask. */ if (~scan->u.bmu_bitmap != 0) { scan->bm_bighint = BLIST_BMAP_RADIX - 1; return (SWAPBLK_NONE); } if (cursor != blk) return (SWAPBLK_NONE); scan->u.bmu_bitmap = 0; scan->bm_bighint = 0; return (blk); } range1 = 0; count1 = count - 1; num_shifts = fls(count1); mask = scan->u.bmu_bitmap; while (mask != 0 && num_shifts > 0) { /* * If bit i is set in mask, then bits in [i, i+range1] are set * in scan->u.bmu_bitmap. The value of range1 is equal to * count1 >> num_shifts. Grow range and reduce num_shifts to 0, * while preserving these invariants. The updates to mask leave * fewer bits set, but each bit that remains set represents a * longer string of consecutive bits set in scan->u.bmu_bitmap. */ num_shifts--; range_ext = range1 + ((count1 >> num_shifts) & 1); mask &= mask >> range_ext; range1 += range_ext; } if (mask == 0) { /* * Update bighint. There is no allocation bigger than range1 * available in this leaf. */ scan->bm_bighint = range1; return (SWAPBLK_NONE); } /* * Discard any candidates that appear before the cursor. */ lo = cursor - blk; mask &= ~(u_daddr_t)0 << lo; if (mask == 0) return (SWAPBLK_NONE); /* * The least significant set bit in mask marks the start of the first * available range of sufficient size. Clear all the bits but that one, * and then perform a binary search to find its position. */ mask &= -mask; hi = BLIST_BMAP_RADIX - count1; while (lo + 1 < hi) { mid = (lo + hi) >> 1; if ((mask >> mid) != 0) lo = mid; else hi = mid; } /* * Set in mask exactly the bits being allocated, and clear them from * the set of available bits. */ mask = (mask << count) - mask; scan->u.bmu_bitmap &= ~mask; return (blk + lo); } /* * blist_meta_alloc() - allocate at a meta in the radix tree. * * Attempt to allocate at a meta node. If we can't, we update * bighint and return a failure. Updating bighint optimize future * calls that hit this node. We have to check for our collapse cases * and we have a few optimizations strewn in as well. */ static daddr_t -blst_meta_alloc(blmeta_t *scan, daddr_t blk, daddr_t count, daddr_t radix, - daddr_t cursor) +blst_meta_alloc(blmeta_t *scan, daddr_t cursor, daddr_t count, u_daddr_t radix) { - daddr_t i, next_skip, r, skip; + daddr_t blk, i, next_skip, r, skip; int child; bool scan_from_start; + blk = cursor & -radix; if (radix == BLIST_BMAP_RADIX) return (blst_leaf_alloc(scan, blk, count, cursor)); if (scan->u.bmu_avail < count) { /* * The meta node's hint must be too large if the allocation * exceeds the number of free blocks. Reduce the hint, and * return failure. */ scan->bm_bighint = scan->u.bmu_avail; return (SWAPBLK_NONE); } skip = radix_to_skip(radix); next_skip = skip / BLIST_META_RADIX; /* * An ALL-FREE meta node requires special handling before allocating * any of its blocks. */ if (scan->u.bmu_avail == radix) { radix /= BLIST_META_RADIX; /* * Reinitialize each of the meta node's children. An ALL-FREE * meta node cannot have a terminator in any subtree. */ for (i = 1; i < skip; i += next_skip) { if (next_skip == 1) scan[i].u.bmu_bitmap = (u_daddr_t)-1; else scan[i].u.bmu_avail = radix; scan[i].bm_bighint = radix; } } else { radix /= BLIST_META_RADIX; } if (count > radix) { /* * The allocation exceeds the number of blocks that are * managed by a subtree of this meta node. */ panic("allocation too large"); } scan_from_start = cursor == blk; child = (cursor - blk) / radix; blk += child * radix; for (i = 1 + child * next_skip; i < skip; i += next_skip) { if (count <= scan[i].bm_bighint) { /* * The allocation might fit in the i'th subtree. */ - r = blst_meta_alloc(&scan[i], blk, count, radix, - cursor > blk ? cursor : blk); + r = blst_meta_alloc(&scan[i], + cursor > blk ? cursor : blk, count, radix); if (r != SWAPBLK_NONE) { scan->u.bmu_avail -= count; return (r); } } else if (scan[i].bm_bighint == (daddr_t)-1) { /* * Terminator */ break; } blk += radix; } /* * We couldn't allocate count in this subtree, update bighint. */ if (scan_from_start && scan->bm_bighint >= count) scan->bm_bighint = count - 1; return (SWAPBLK_NONE); } /* * BLST_LEAF_FREE() - free allocated block from leaf bitmap * */ static void blst_leaf_free(blmeta_t *scan, daddr_t blk, int count) { /* * free some data in this bitmap * * e.g. * 0000111111111110000 * \_________/\__/ * v n */ int n = blk & (BLIST_BMAP_RADIX - 1); u_daddr_t mask; mask = ((u_daddr_t)-1 << n) & ((u_daddr_t)-1 >> (BLIST_BMAP_RADIX - count - n)); if (scan->u.bmu_bitmap & mask) panic("blst_radix_free: freeing free block"); scan->u.bmu_bitmap |= mask; /* * We could probably do a better job here. We are required to make * bighint at least as large as the biggest contiguous block of * data. If we just shoehorn it, a little extra overhead will * be incured on the next allocation (but only that one typically). */ scan->bm_bighint = BLIST_BMAP_RADIX; } /* * BLST_META_FREE() - free allocated blocks from radix tree meta info * * This support routine frees a range of blocks from the bitmap. * The range must be entirely enclosed by this radix node. If a * meta node, we break the range down recursively to free blocks * in subnodes (which means that this code can free an arbitrary * range whereas the allocation code cannot allocate an arbitrary * range). */ static void -blst_meta_free(blmeta_t *scan, daddr_t freeBlk, daddr_t count, daddr_t radix, - daddr_t blk) +blst_meta_free(blmeta_t *scan, daddr_t freeBlk, daddr_t count, u_daddr_t radix) { - daddr_t i, next_skip, skip, v; + daddr_t blk, i, next_skip, skip, v; int child; if (scan->bm_bighint == (daddr_t)-1) panic("freeing invalid range"); if (radix == BLIST_BMAP_RADIX) return (blst_leaf_free(scan, freeBlk, count)); skip = radix_to_skip(radix); next_skip = skip / BLIST_META_RADIX; if (scan->u.bmu_avail == 0) { /* * ALL-ALLOCATED special case, with possible * shortcut to ALL-FREE special case. */ scan->u.bmu_avail = count; scan->bm_bighint = count; if (count != radix) { for (i = 1; i < skip; i += next_skip) { if (scan[i].bm_bighint == (daddr_t)-1) break; scan[i].bm_bighint = 0; if (next_skip == 1) { scan[i].u.bmu_bitmap = 0; } else { scan[i].u.bmu_avail = 0; } } /* fall through */ } } else { scan->u.bmu_avail += count; /* scan->bm_bighint = radix; */ } /* * ALL-FREE special case. */ if (scan->u.bmu_avail == radix) return; if (scan->u.bmu_avail > radix) panic("blst_meta_free: freeing already free blocks (%lld) %lld/%lld", (long long)count, (long long)scan->u.bmu_avail, (long long)radix); /* * Break the free down into its components */ + blk = freeBlk & -radix; radix /= BLIST_META_RADIX; child = (freeBlk - blk) / radix; blk += child * radix; i = 1 + child * next_skip; while (i < skip && blk < freeBlk + count) { v = blk + radix - freeBlk; if (v > count) v = count; - blst_meta_free(&scan[i], freeBlk, v, radix, blk); + blst_meta_free(&scan[i], freeBlk, v, radix); if (scan->bm_bighint < scan[i].bm_bighint) scan->bm_bighint = scan[i].bm_bighint; count -= v; freeBlk += v; blk += radix; i += next_skip; } } /* * BLIST_RADIX_COPY() - copy one radix tree to another * * Locates free space in the source tree and frees it in the destination * tree. The space may not already be free in the destination. */ static void blst_copy(blmeta_t *scan, daddr_t blk, daddr_t radix, blist_t dest, daddr_t count) { daddr_t i, next_skip, skip; /* * Leaf node */ if (radix == BLIST_BMAP_RADIX) { u_daddr_t v = scan->u.bmu_bitmap; if (v == (u_daddr_t)-1) { blist_free(dest, blk, count); } else if (v != 0) { int i; for (i = 0; i < BLIST_BMAP_RADIX && i < count; ++i) { if (v & ((u_daddr_t)1 << i)) blist_free(dest, blk + i, 1); } } return; } /* * Meta node */ if (scan->u.bmu_avail == 0) { /* * Source all allocated, leave dest allocated */ return; } if (scan->u.bmu_avail == radix) { /* * Source all free, free entire dest */ if (count < radix) blist_free(dest, blk, count); else blist_free(dest, blk, radix); return; } skip = radix_to_skip(radix); next_skip = skip / BLIST_META_RADIX; radix /= BLIST_META_RADIX; for (i = 1; count && i < skip; i += next_skip) { if (scan[i].bm_bighint == (daddr_t)-1) break; if (count >= radix) { blst_copy(&scan[i], blk, radix, dest, radix); count -= radix; } else { if (count) { blst_copy(&scan[i], blk, radix, dest, count); } count = 0; } blk += radix; } } /* * BLST_LEAF_FILL() - allocate specific blocks in leaf bitmap * * This routine allocates all blocks in the specified range * regardless of any existing allocations in that range. Returns * the number of blocks allocated by the call. */ static daddr_t blst_leaf_fill(blmeta_t *scan, daddr_t blk, int count) { int n = blk & (BLIST_BMAP_RADIX - 1); daddr_t nblks; u_daddr_t mask; mask = ((u_daddr_t)-1 << n) & ((u_daddr_t)-1 >> (BLIST_BMAP_RADIX - count - n)); /* Count the number of blocks that we are allocating. */ nblks = bitcount64(scan->u.bmu_bitmap & mask); scan->u.bmu_bitmap &= ~mask; return (nblks); } /* * BLIST_META_FILL() - allocate specific blocks at a meta node * * This routine allocates the specified range of blocks, * regardless of any existing allocations in the range. The * range must be within the extent of this node. Returns the * number of blocks allocated by the call. */ static daddr_t -blst_meta_fill(blmeta_t *scan, daddr_t allocBlk, daddr_t count, daddr_t radix, - daddr_t blk) +blst_meta_fill(blmeta_t *scan, daddr_t allocBlk, daddr_t count, u_daddr_t radix) { - daddr_t i, nblks, next_skip, skip, v; + daddr_t blk, i, nblks, next_skip, skip, v; int child; if (scan->bm_bighint == (daddr_t)-1) panic("filling invalid range"); if (count > radix) { /* * The allocation exceeds the number of blocks that are * managed by this node. */ panic("fill too large"); } if (radix == BLIST_BMAP_RADIX) return (blst_leaf_fill(scan, allocBlk, count)); if (count == radix || scan->u.bmu_avail == 0) { /* * ALL-ALLOCATED special case */ nblks = scan->u.bmu_avail; scan->u.bmu_avail = 0; scan->bm_bighint = 0; return (nblks); } skip = radix_to_skip(radix); next_skip = skip / BLIST_META_RADIX; + blk = allocBlk & -radix; /* * An ALL-FREE meta node requires special handling before allocating * any of its blocks. */ if (scan->u.bmu_avail == radix) { radix /= BLIST_META_RADIX; /* * Reinitialize each of the meta node's children. An ALL-FREE * meta node cannot have a terminator in any subtree. */ for (i = 1; i < skip; i += next_skip) { if (next_skip == 1) scan[i].u.bmu_bitmap = (u_daddr_t)-1; else scan[i].u.bmu_avail = radix; scan[i].bm_bighint = radix; } } else { radix /= BLIST_META_RADIX; } nblks = 0; child = (allocBlk - blk) / radix; blk += child * radix; i = 1 + child * next_skip; while (i < skip && blk < allocBlk + count) { v = blk + radix - allocBlk; if (v > count) v = count; - nblks += blst_meta_fill(&scan[i], allocBlk, v, radix, blk); + nblks += blst_meta_fill(&scan[i], allocBlk, v, radix); count -= v; allocBlk += v; blk += radix; i += next_skip; } scan->u.bmu_avail -= nblks; return (nblks); } /* * BLST_RADIX_INIT() - initialize radix tree * * Initialize our meta structures and bitmaps and calculate the exact * amount of space required to manage 'count' blocks - this space may * be considerably less than the calculated radix due to the large * RADIX values we use. */ static daddr_t blst_radix_init(blmeta_t *scan, daddr_t radix, daddr_t count) { daddr_t i, memindex, next_skip, skip; memindex = 0; /* * Leaf node */ if (radix == BLIST_BMAP_RADIX) { if (scan) { scan->bm_bighint = 0; scan->u.bmu_bitmap = 0; } return (memindex); } /* * Meta node. If allocating the entire object we can special * case it. However, we need to figure out how much memory * is required to manage 'count' blocks, so we continue on anyway. */ if (scan) { scan->bm_bighint = 0; scan->u.bmu_avail = 0; } skip = radix_to_skip(radix); next_skip = skip / BLIST_META_RADIX; radix /= BLIST_META_RADIX; for (i = 1; i < skip; i += next_skip) { if (count >= radix) { /* * Allocate the entire object */ memindex = i + blst_radix_init(((scan) ? &scan[i] : NULL), radix, radix); count -= radix; } else if (count > 0) { /* * Allocate a partial object */ memindex = i + blst_radix_init(((scan) ? &scan[i] : NULL), radix, count); count = 0; } else { /* * Add terminator and break out */ if (scan) scan[i].bm_bighint = (daddr_t)-1; break; } } if (memindex < i) memindex = i; return (memindex); } #ifdef BLIST_DEBUG static void blst_radix_print(blmeta_t *scan, daddr_t blk, daddr_t radix, int tab) { daddr_t i, next_skip, skip; if (radix == BLIST_BMAP_RADIX) { printf( "%*.*s(%08llx,%lld): bitmap %016llx big=%lld\n", tab, tab, "", (long long)blk, (long long)radix, (long long)scan->u.bmu_bitmap, (long long)scan->bm_bighint ); return; } if (scan->u.bmu_avail == 0) { printf( "%*.*s(%08llx,%lld) ALL ALLOCATED\n", tab, tab, "", (long long)blk, (long long)radix ); return; } if (scan->u.bmu_avail == radix) { printf( "%*.*s(%08llx,%lld) ALL FREE\n", tab, tab, "", (long long)blk, (long long)radix ); return; } printf( "%*.*s(%08llx,%lld): subtree (%lld/%lld) big=%lld {\n", tab, tab, "", (long long)blk, (long long)radix, (long long)scan->u.bmu_avail, (long long)radix, (long long)scan->bm_bighint ); skip = radix_to_skip(radix); next_skip = skip / BLIST_META_RADIX; radix /= BLIST_META_RADIX; tab += 4; for (i = 1; i < skip; i += next_skip) { if (scan[i].bm_bighint == (daddr_t)-1) { printf( "%*.*s(%08llx,%lld): Terminator\n", tab, tab, "", (long long)blk, (long long)radix ); break; } blst_radix_print(&scan[i], blk, radix, tab); blk += radix; } tab -= 4; printf( "%*.*s}\n", tab, tab, "" ); } #endif #ifdef BLIST_DEBUG int main(int ac, char **av) { int size = 1024; int i; blist_t bl; for (i = 1; i < ac; ++i) { const char *ptr = av[i]; if (*ptr != '-') { size = strtol(ptr, NULL, 0); continue; } ptr += 2; fprintf(stderr, "Bad option: %s\n", ptr - 2); exit(1); } bl = blist_create(size, M_WAITOK); blist_free(bl, 0, size); for (;;) { char buf[1024]; long long da = 0; long long count = 0; printf("%lld/%lld/%lld> ", (long long)blist_avail(bl), (long long)size, (long long)bl->bl_radix); fflush(stdout); if (fgets(buf, sizeof(buf), stdin) == NULL) break; switch(buf[0]) { case 'r': if (sscanf(buf + 1, "%lld", &count) == 1) { blist_resize(&bl, count, 1, M_WAITOK); } else { printf("?\n"); } case 'p': blist_print(bl); break; case 'a': if (sscanf(buf + 1, "%lld", &count) == 1) { daddr_t blk = blist_alloc(bl, count); printf(" R=%08llx\n", (long long)blk); } else { printf("?\n"); } break; case 'f': if (sscanf(buf + 1, "%llx %lld", &da, &count) == 2) { blist_free(bl, da, count); } else { printf("?\n"); } break; case 'l': if (sscanf(buf + 1, "%llx %lld", &da, &count) == 2) { printf(" n=%jd\n", (intmax_t)blist_fill(bl, da, count)); } else { printf("?\n"); } break; case '?': case 'h': puts( "p -print\n" "a %d -allocate\n" "f %x %d -free\n" "l %x %d -fill\n" "r %d -resize\n" "h/? -help" ); break; default: printf("?\n"); break; } } return(0); } void panic(const char *ctl, ...) { va_list va; va_start(va, ctl); vfprintf(stderr, ctl, va); fprintf(stderr, "\n"); va_end(va); exit(1); } #endif Index: stable/11/sys/sys/blist.h =================================================================== --- stable/11/sys/sys/blist.h (revision 324129) +++ stable/11/sys/sys/blist.h (revision 324130) @@ -1,103 +1,103 @@ /*- * Copyright (c) 1998 Matthew Dillon. 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. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * 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. */ /* * Implements bitmap resource lists. * * Usage: * blist = blist_create(blocks, flags) * (void) blist_destroy(blist) * blkno = blist_alloc(blist, count) * (void) blist_free(blist, blkno, count) * nblks = blist_fill(blist, blkno, count) * (void) blist_resize(&blist, count, freeextra, flags) * * * Notes: * on creation, the entire list is marked reserved. You should * first blist_free() the sections you want to make available * for allocation before doing general blist_alloc()/free() * ops. * * SWAPBLK_NONE is returned on failure. This module is typically * capable of managing up to (2^63) blocks per blist, though * the memory utilization would be insane if you actually did * that. Managing something like 512MB worth of 4K blocks * eats around 32 KBytes of memory. * * $FreeBSD$ */ #ifndef _SYS_BLIST_H_ #define _SYS_BLIST_H_ typedef uint64_t u_daddr_t; /* unsigned disk address */ /* * note: currently use SWAPBLK_NONE as an absolute value rather then * a flag bit. */ #define SWAPBLK_MASK ((daddr_t)((u_daddr_t)-1 >> 1)) /* mask */ #define SWAPBLK_NONE ((daddr_t)((u_daddr_t)SWAPBLK_MASK + 1))/* flag */ /* * Both blmeta and bmu_bitmap MUST be a power of 2 in size. */ typedef struct blmeta { union { daddr_t bmu_avail; /* space available under us */ u_daddr_t bmu_bitmap; /* bitmap if we are a leaf */ } u; daddr_t bm_bighint; /* biggest contiguous block hint*/ } blmeta_t; typedef struct blist { daddr_t bl_blocks; /* area of coverage */ - daddr_t bl_radix; /* coverage radix */ + u_daddr_t bl_radix; /* coverage radix */ daddr_t bl_cursor; /* next-fit search starts at */ blmeta_t *bl_root; /* root of radix tree */ } *blist_t; #define BLIST_META_RADIX 16 #define BLIST_BMAP_RADIX (sizeof(u_daddr_t)*8) #define BLIST_MAX_ALLOC BLIST_BMAP_RADIX daddr_t blist_alloc(blist_t blist, daddr_t count); daddr_t blist_avail(blist_t blist); blist_t blist_create(daddr_t blocks, int flags); void blist_destroy(blist_t blist); daddr_t blist_fill(blist_t bl, daddr_t blkno, daddr_t count); void blist_free(blist_t blist, daddr_t blkno, daddr_t count); void blist_print(blist_t blist); void blist_resize(blist_t *pblist, daddr_t count, int freenew, int flags); #endif /* _SYS_BLIST_H_ */ Index: stable/11 =================================================================== --- stable/11 (revision 324129) +++ stable/11 (revision 324130) Property changes on: stable/11 ___________________________________________________________________ Modified: svn:mergeinfo ## -0,0 +0,1 ## Merged /head:r322459,322897