Track dirty and clean runs separately.

Split arena->runs_avail into arena->runs_avail_{clean,dirty}, and
preferentially allocate dirty runs.
This commit is contained in:
Jason Evans 2010-03-18 20:36:40 -07:00
parent dafde14e08
commit 19b3d61892
4 changed files with 285 additions and 226 deletions

View File

@ -82,7 +82,7 @@ struct arena_chunk_map_s {
/* /*
* Linkage for run trees. There are two disjoint uses: * Linkage for run trees. There are two disjoint uses:
* *
* 1) arena_t's runs_avail tree. * 1) arena_t's runs_avail_{clean,dirty} trees.
* 2) arena_run_t conceptually uses this linkage for in-use * 2) arena_run_t conceptually uses this linkage for in-use
* non-full runs, rather than directly embedding linkage. * non-full runs, rather than directly embedding linkage.
*/ */
@ -105,11 +105,11 @@ struct arena_chunk_map_s {
* Run address (or size) and various flags are stored together. The bit * Run address (or size) and various flags are stored together. The bit
* layout looks like (assuming 32-bit system): * layout looks like (assuming 32-bit system):
* *
* ???????? ???????? ????cccc ccccdzla * ???????? ???????? ????---- ----dzla
* *
* ? : Unallocated: Run address for first/last pages, unset for internal * ? : Unallocated: Run address for first/last pages, unset for internal
* pages. * pages.
* Small: Don't care. * Small: Run page offset.
* Large: Run size for first page, unset for trailing pages. * Large: Run size for first page, unset for trailing pages.
* - : Unused. * - : Unused.
* d : dirty? * d : dirty?
@ -123,34 +123,36 @@ struct arena_chunk_map_s {
* s : run size * s : run size
* x : don't care * x : don't care
* - : 0 * - : 0
* [dzla] : bit set * [DZLA] : bit set
* [dzla] : bit unset
* *
* Unallocated: * Unallocated (clean):
* ssssssss ssssssss ssss---- -------- * ssssssss ssssssss ssss---- ----dz--
* xxxxxxxx xxxxxxxx xxxx---- ----d--- * xxxxxxxx xxxxxxxx xxxx---- -----Zxx
* ssssssss ssssssss ssss---- -----z-- * ssssssss ssssssss ssss---- ----dZ--
*
* Unallocated (dirty):
* ssssssss ssssssss ssss---- ----D---
* xxxxxxxx xxxxxxxx xxxx---- ----xxxx
* ssssssss ssssssss ssss---- ----D---
* *
* Small: * Small:
* pppppppp pppppppp pppp---- ----d--a
* pppppppp pppppppp pppp---- -------a * pppppppp pppppppp pppp---- -------a
* pppppppp pppppppp pppp---- -------a * pppppppp pppppppp pppp---- ----d--a
* pppppppp pppppppp pppp---- -------a
* *
* Large: * Large:
* ssssssss ssssssss ssss---- ------la * ssssssss ssssssss ssss---- ----D-la
* -------- -------- -------- ------la * xxxxxxxx xxxxxxxx xxxx---- ----xxxx
* -------- -------- -------- ------la * -------- -------- -------- ----D-la
*/ */
size_t bits; size_t bits;
#define CHUNK_MAP_PG_MASK ((size_t)0xfffff000U) #define CHUNK_MAP_FLAGS_MASK ((size_t)0x1fU)
#define CHUNK_MAP_PG_SHIFT 12 #define CHUNK_MAP_KEY ((size_t)0x10U)
#define CHUNK_MAP_LG_PG_RANGE 20 #define CHUNK_MAP_DIRTY ((size_t)0x08U)
#define CHUNK_MAP_ZEROED ((size_t)0x04U)
#define CHUNK_MAP_FLAGS_MASK ((size_t)0xfU) #define CHUNK_MAP_LARGE ((size_t)0x02U)
#define CHUNK_MAP_DIRTY ((size_t)0x8U) #define CHUNK_MAP_ALLOCATED ((size_t)0x01U)
#define CHUNK_MAP_ZEROED ((size_t)0x4U)
#define CHUNK_MAP_LARGE ((size_t)0x2U)
#define CHUNK_MAP_ALLOCATED ((size_t)0x1U)
#define CHUNK_MAP_KEY (CHUNK_MAP_DIRTY | CHUNK_MAP_ALLOCATED)
}; };
typedef rb_tree(arena_chunk_map_t) arena_avail_tree_t; typedef rb_tree(arena_chunk_map_t) arena_avail_tree_t;
typedef rb_tree(arena_chunk_map_t) arena_run_tree_t; typedef rb_tree(arena_chunk_map_t) arena_run_tree_t;
@ -312,10 +314,19 @@ struct arena_s {
size_t npurgatory; size_t npurgatory;
/* /*
* Size/address-ordered tree of this arena's available runs. This tree * Size/address-ordered trees of this arena's available runs. The trees
* is used for first-best-fit run allocation. * are used for first-best-fit run allocation. The dirty tree contains
* runs with dirty pages (i.e. very likely to have been touched and
* therefore have associated physical pages), whereas the clean tree
* contains runs with pages that either have no associated physical
* pages, or have pages that the kernel may recycle at any time due to
* previous madvise(2) calls. The dirty tree is used in preference to
* the clean tree for allocations, because using dirty pages reduces
* the amount of dirty purging necessary to keep the active:dirty page
* ratio below the purge threshold.
*/ */
arena_avail_tree_t runs_avail; arena_avail_tree_t runs_avail_clean;
arena_avail_tree_t runs_avail_dirty;
/* /*
* bins is used to store trees of free regions of the following sizes, * bins is used to store trees of free regions of the following sizes,
@ -465,9 +476,8 @@ arena_dalloc(arena_t *arena, arena_chunk_t *chunk, void *ptr)
arena_bin_t *bin; arena_bin_t *bin;
run = (arena_run_t *)((uintptr_t)chunk + run = (arena_run_t *)((uintptr_t)chunk +
(uintptr_t)((pageind - ((mapelm->bits & (uintptr_t)((pageind - (mapelm->bits >>
CHUNK_MAP_PG_MASK) >> CHUNK_MAP_PG_SHIFT)) << PAGE_SHIFT)) << PAGE_SHIFT));
PAGE_SHIFT));
assert(run->magic == ARENA_RUN_MAGIC); assert(run->magic == ARENA_RUN_MAGIC);
assert(((uintptr_t)ptr - ((uintptr_t)run + assert(((uintptr_t)ptr - ((uintptr_t)run +
(uintptr_t)run->bin->reg0_offset)) % (uintptr_t)run->bin->reg0_offset)) %

View File

@ -294,8 +294,7 @@ tcache_dalloc_small(tcache_t *tcache, void *ptr)
pageind = (((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT); pageind = (((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT);
mapelm = &chunk->map[pageind]; mapelm = &chunk->map[pageind];
run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind - run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind -
((mapelm->bits & CHUNK_MAP_PG_MASK) >> CHUNK_MAP_PG_SHIFT)) << (mapelm->bits >> PAGE_SHIFT)) << PAGE_SHIFT));
PAGE_SHIFT));
assert(run->magic == ARENA_RUN_MAGIC); assert(run->magic == ARENA_RUN_MAGIC);
bin = run->bin; bin = run->bin;
binind = ((uintptr_t)bin - (uintptr_t)&arena->bins) / binind = ((uintptr_t)bin - (uintptr_t)&arena->bins) /

View File

@ -215,6 +215,9 @@ arena_avail_comp(arena_chunk_map_t *a, arena_chunk_map_t *b)
size_t a_size = a->bits & ~PAGE_MASK; size_t a_size = a->bits & ~PAGE_MASK;
size_t b_size = b->bits & ~PAGE_MASK; size_t b_size = b->bits & ~PAGE_MASK;
assert(a->bits & CHUNK_MAP_KEY || (a->bits & CHUNK_MAP_DIRTY) ==
(b->bits & CHUNK_MAP_DIRTY));
ret = (a_size > b_size) - (a_size < b_size); ret = (a_size > b_size) - (a_size < b_size);
if (ret == 0) { if (ret == 0) {
uintptr_t a_mapelm, b_mapelm; uintptr_t a_mapelm, b_mapelm;
@ -290,69 +293,107 @@ arena_run_split(arena_t *arena, arena_run_t *run, size_t size, bool large,
{ {
arena_chunk_t *chunk; arena_chunk_t *chunk;
size_t old_ndirty, run_ind, total_pages, need_pages, rem_pages, i; size_t old_ndirty, run_ind, total_pages, need_pages, rem_pages, i;
size_t flag_dirty;
arena_avail_tree_t *runs_avail;
chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(run); chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(run);
old_ndirty = chunk->ndirty; old_ndirty = chunk->ndirty;
run_ind = (unsigned)(((uintptr_t)run - (uintptr_t)chunk) run_ind = (unsigned)(((uintptr_t)run - (uintptr_t)chunk)
>> PAGE_SHIFT); >> PAGE_SHIFT);
flag_dirty = chunk->map[run_ind].bits & CHUNK_MAP_DIRTY;
runs_avail = (flag_dirty != 0) ? &arena->runs_avail_dirty :
&arena->runs_avail_clean;
total_pages = (chunk->map[run_ind].bits & ~PAGE_MASK) >> total_pages = (chunk->map[run_ind].bits & ~PAGE_MASK) >>
PAGE_SHIFT; PAGE_SHIFT;
assert((chunk->map[run_ind+total_pages-1].bits & CHUNK_MAP_DIRTY) ==
flag_dirty);
need_pages = (size >> PAGE_SHIFT); need_pages = (size >> PAGE_SHIFT);
assert(need_pages > 0); assert(need_pages > 0);
assert(need_pages <= total_pages); assert(need_pages <= total_pages);
rem_pages = total_pages - need_pages; rem_pages = total_pages - need_pages;
arena_avail_tree_remove(&arena->runs_avail, &chunk->map[run_ind]); arena_avail_tree_remove(runs_avail, &chunk->map[run_ind]);
arena->nactive += need_pages; arena->nactive += need_pages;
/* Keep track of trailing unused pages for later use. */ /* Keep track of trailing unused pages for later use. */
if (rem_pages > 0) { if (rem_pages > 0) {
chunk->map[run_ind+need_pages].bits = (rem_pages << if (flag_dirty != 0) {
PAGE_SHIFT) | (chunk->map[run_ind+need_pages].bits & chunk->map[run_ind+need_pages].bits = (rem_pages <<
CHUNK_MAP_FLAGS_MASK); PAGE_SHIFT) | CHUNK_MAP_DIRTY;
chunk->map[run_ind+total_pages-1].bits = (rem_pages << chunk->map[run_ind+total_pages-1].bits = (rem_pages <<
PAGE_SHIFT) | (chunk->map[run_ind+total_pages-1].bits & PAGE_SHIFT) | CHUNK_MAP_DIRTY;
CHUNK_MAP_FLAGS_MASK); } else {
arena_avail_tree_insert(&arena->runs_avail, chunk->map[run_ind+need_pages].bits = (rem_pages <<
PAGE_SHIFT) | (chunk->map[run_ind+need_pages].bits &
CHUNK_MAP_ZEROED);
chunk->map[run_ind+total_pages-1].bits = (rem_pages <<
PAGE_SHIFT) |
(chunk->map[run_ind+total_pages-1].bits &
CHUNK_MAP_ZEROED);
}
arena_avail_tree_insert(runs_avail,
&chunk->map[run_ind+need_pages]); &chunk->map[run_ind+need_pages]);
} }
for (i = 0; i < need_pages; i++) { /* Update dirty page accounting. */
/* Zero if necessary. */ if (flag_dirty != 0) {
chunk->ndirty -= need_pages;
arena->ndirty -= need_pages;
}
/*
* Update the page map separately for large vs. small runs, since it is
* possible to avoid iteration for large mallocs.
*/
if (large) {
if (zero) { if (zero) {
if ((chunk->map[run_ind + i].bits & CHUNK_MAP_ZEROED) if (flag_dirty == 0) {
== 0) { /*
memset((void *)((uintptr_t)chunk + ((run_ind * The run is clean, so some pages may be
+ i) << PAGE_SHIFT)), 0, PAGE_SIZE); * zeroed (i.e. never before touched).
/* CHUNK_MAP_ZEROED is cleared below. */ */
for (i = 0; i < need_pages; i++) {
if ((chunk->map[run_ind + i].bits &
CHUNK_MAP_ZEROED) == 0) {
memset((void *)((uintptr_t)
chunk + ((run_ind + i) <<
PAGE_SHIFT)), 0,
PAGE_SIZE);
}
}
} else {
/*
* The run is dirty, so all pages must be
* zeroed.
*/
memset((void *)((uintptr_t)chunk + (run_ind <<
PAGE_SHIFT)), 0, (need_pages <<
PAGE_SHIFT));
} }
} }
/* Update dirty page accounting. */
if (chunk->map[run_ind + i].bits & CHUNK_MAP_DIRTY) {
chunk->ndirty--;
arena->ndirty--;
/* CHUNK_MAP_DIRTY is cleared below. */
}
/* Initialize the chunk map. */
if (large) {
chunk->map[run_ind + i].bits = CHUNK_MAP_LARGE
| CHUNK_MAP_ALLOCATED;
} else {
chunk->map[run_ind + i].bits = (i << CHUNK_MAP_PG_SHIFT)
| CHUNK_MAP_ALLOCATED;
}
}
if (large) {
/* /*
* Set the run size only in the first element for large runs. * Set the last element first, in case the run only contains one
* This is primarily a debugging aid, since the lack of size * page (i.e. both statements set the same element).
* info for trailing pages only matters if the application
* tries to operate on an interior pointer.
*/ */
chunk->map[run_ind].bits |= size; chunk->map[run_ind+need_pages-1].bits = CHUNK_MAP_LARGE |
CHUNK_MAP_ALLOCATED | flag_dirty;
chunk->map[run_ind].bits = size | CHUNK_MAP_LARGE |
CHUNK_MAP_ALLOCATED | flag_dirty;
} else {
assert(zero == false);
/*
* Propagate the dirty flag to the allocated small run, so that
* arena_dalloc_bin_run() has the ability to conditionally trim
* clean pages.
*/
chunk->map[run_ind].bits = CHUNK_MAP_ALLOCATED | flag_dirty;
for (i = 1; i < need_pages - 1; i++) {
chunk->map[run_ind + i].bits = (i << PAGE_SHIFT)
| CHUNK_MAP_ALLOCATED;
}
chunk->map[run_ind + need_pages - 1].bits = ((need_pages - 1) <<
PAGE_SHIFT) | CHUNK_MAP_ALLOCATED | flag_dirty;
} }
} }
@ -363,8 +404,19 @@ arena_chunk_alloc(arena_t *arena)
size_t i; size_t i;
if (arena->spare != NULL) { if (arena->spare != NULL) {
arena_avail_tree_t *runs_avail;
chunk = arena->spare; chunk = arena->spare;
arena->spare = NULL; arena->spare = NULL;
/* Insert the run into the appropriate runs_avail_* tree. */
if ((chunk->map[arena_chunk_header_npages].bits &
CHUNK_MAP_DIRTY) == 0)
runs_avail = &arena->runs_avail_clean;
else
runs_avail = &arena->runs_avail_dirty;
arena_avail_tree_insert(runs_avail,
&chunk->map[arena_chunk_header_npages]);
} else { } else {
bool zero; bool zero;
size_t zeroed; size_t zeroed;
@ -401,11 +453,11 @@ arena_chunk_alloc(arena_t *arena)
for (i++; i < chunk_npages-1; i++) for (i++; i < chunk_npages-1; i++)
chunk->map[i].bits = zeroed; chunk->map[i].bits = zeroed;
chunk->map[chunk_npages-1].bits = arena_maxclass | zeroed; chunk->map[chunk_npages-1].bits = arena_maxclass | zeroed;
}
/* Insert the run into the runs_avail tree. */ /* Insert the run into the runs_avail_clean tree. */
arena_avail_tree_insert(&arena->runs_avail, arena_avail_tree_insert(&arena->runs_avail_clean,
&chunk->map[arena_chunk_header_npages]); &chunk->map[arena_chunk_header_npages]);
}
return (chunk); return (chunk);
} }
@ -413,6 +465,7 @@ arena_chunk_alloc(arena_t *arena)
static void static void
arena_chunk_dealloc(arena_t *arena, arena_chunk_t *chunk) arena_chunk_dealloc(arena_t *arena, arena_chunk_t *chunk)
{ {
arena_avail_tree_t *runs_avail;
while (arena->spare != NULL) { while (arena->spare != NULL) {
arena_chunk_t *spare = arena->spare; arena_chunk_t *spare = arena->spare;
@ -432,10 +485,15 @@ arena_chunk_dealloc(arena_t *arena, arena_chunk_t *chunk)
} }
/* /*
* Remove run from runs_avail, regardless of whether this chunk will be * Remove run from the appropriate runs_avail_* tree, so that the arena
* cached, so that the arena does not use it. * does not use it.
*/ */
arena_avail_tree_remove(&arena->runs_avail, if ((chunk->map[arena_chunk_header_npages].bits &
CHUNK_MAP_DIRTY) == 0)
runs_avail = &arena->runs_avail_clean;
else
runs_avail = &arena->runs_avail_dirty;
arena_avail_tree_remove(runs_avail,
&chunk->map[arena_chunk_header_npages]); &chunk->map[arena_chunk_header_npages]);
arena->spare = chunk; arena->spare = chunk;
@ -453,7 +511,18 @@ arena_run_alloc(arena_t *arena, size_t size, bool large, bool zero)
/* Search the arena's chunks for the lowest best fit. */ /* Search the arena's chunks for the lowest best fit. */
key.bits = size | CHUNK_MAP_KEY; key.bits = size | CHUNK_MAP_KEY;
mapelm = arena_avail_tree_nsearch(&arena->runs_avail, &key); mapelm = arena_avail_tree_nsearch(&arena->runs_avail_dirty, &key);
if (mapelm != NULL) {
arena_chunk_t *run_chunk = CHUNK_ADDR2BASE(mapelm);
size_t pageind = ((uintptr_t)mapelm - (uintptr_t)run_chunk->map)
/ sizeof(arena_chunk_map_t);
run = (arena_run_t *)((uintptr_t)run_chunk + (pageind <<
PAGE_SHIFT));
arena_run_split(arena, run, size, large, zero);
return (run);
}
mapelm = arena_avail_tree_nsearch(&arena->runs_avail_clean, &key);
if (mapelm != NULL) { if (mapelm != NULL) {
arena_chunk_t *run_chunk = CHUNK_ADDR2BASE(mapelm); arena_chunk_t *run_chunk = CHUNK_ADDR2BASE(mapelm);
size_t pageind = ((uintptr_t)mapelm - (uintptr_t)run_chunk->map) size_t pageind = ((uintptr_t)mapelm - (uintptr_t)run_chunk->map)
@ -481,7 +550,18 @@ arena_run_alloc(arena_t *arena, size_t size, bool large, bool zero)
* sufficient memory available while this one dropped arena->lock in * sufficient memory available while this one dropped arena->lock in
* arena_chunk_alloc(), so search one more time. * arena_chunk_alloc(), so search one more time.
*/ */
mapelm = arena_avail_tree_nsearch(&arena->runs_avail, &key); mapelm = arena_avail_tree_nsearch(&arena->runs_avail_dirty, &key);
if (mapelm != NULL) {
arena_chunk_t *run_chunk = CHUNK_ADDR2BASE(mapelm);
size_t pageind = ((uintptr_t)mapelm - (uintptr_t)run_chunk->map)
/ sizeof(arena_chunk_map_t);
run = (arena_run_t *)((uintptr_t)run_chunk + (pageind <<
PAGE_SHIFT));
arena_run_split(arena, run, size, large, zero);
return (run);
}
mapelm = arena_avail_tree_nsearch(&arena->runs_avail_clean, &key);
if (mapelm != NULL) { if (mapelm != NULL) {
arena_chunk_t *run_chunk = CHUNK_ADDR2BASE(mapelm); arena_chunk_t *run_chunk = CHUNK_ADDR2BASE(mapelm);
size_t pageind = ((uintptr_t)mapelm - (uintptr_t)run_chunk->map) size_t pageind = ((uintptr_t)mapelm - (uintptr_t)run_chunk->map)
@ -525,67 +605,61 @@ arena_chunk_purge(arena_t *arena, arena_chunk_t *chunk)
/* /*
* If chunk is the spare, temporarily re-allocate it, 1) so that its * If chunk is the spare, temporarily re-allocate it, 1) so that its
* run is reinserted into runs_avail, and 2) so that it cannot be * run is reinserted into runs_avail_dirty, and 2) so that it cannot be
* completely discarded by another thread while arena->lock is dropped * completely discarded by another thread while arena->lock is dropped
* by this thread. Note that the arena_run_dalloc() call will * by this thread. Note that the arena_run_dalloc() call will
* implicitly deallocate the chunk, so no explicit action is required * implicitly deallocate the chunk, so no explicit action is required
* in this function to deallocate the chunk. * in this function to deallocate the chunk.
*
* Note that once a chunk contains dirty pages, it cannot again contain
* a single run unless 1) it is a dirty run, or 2) this function purges
* dirty pages and causes the transition to a single clean run. Thus
* (chunk == arena->spare) is possible, but it is not possible for
* this function to be called on the spare unless it contains a dirty
* run.
*/ */
if (chunk == arena->spare) if (chunk == arena->spare) {
assert((chunk->map[arena_chunk_header_npages].bits &
CHUNK_MAP_DIRTY) != 0);
arena_chunk_alloc(arena); arena_chunk_alloc(arena);
}
/* Temporarily allocate all free runs that contain dirty pages. */ /* Temporarily allocate all free dirty runs within chunk. */
for (pageind = arena_chunk_header_npages; pageind < chunk_npages;) { for (pageind = arena_chunk_header_npages; pageind < chunk_npages;) {
mapelm = &chunk->map[pageind]; mapelm = &chunk->map[pageind];
if ((mapelm->bits & CHUNK_MAP_ALLOCATED) == 0) { if ((mapelm->bits & CHUNK_MAP_ALLOCATED) == 0) {
size_t npages, i; size_t npages;
npages = (mapelm->bits & CHUNK_MAP_PG_MASK) >> npages = mapelm->bits >> PAGE_SHIFT;
CHUNK_MAP_PG_SHIFT;
assert(pageind + npages <= chunk_npages); assert(pageind + npages <= chunk_npages);
for (i = 0; i < npages; i++) { if (mapelm->bits & CHUNK_MAP_DIRTY) {
if (chunk->map[pageind + i].bits & /*
CHUNK_MAP_DIRTY) { * Dirty run; temporarily allocate it. Set the
/* * last map element first, in case this is a
* This run contains at least one dirty * one-page run.
* page. Temporarily allocate it. */
* Don't bother setting the arena_avail_tree_remove(
* CHUNK_MAP_ALLOCATED bit for interior &arena->runs_avail_dirty, mapelm);
* pages yet. The bit will be set chunk->map[pageind + npages - 1].bits =
* during the loop that actually does (CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED);
* the madvise() calls, so that the run mapelm->bits = (npages << PAGE_SHIFT) |
* looks like a normal large run by the CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED;
* time it is passed to arena->nactive += npages;
* arena_run_dalloc(). /* Append to list for later processing. */
*/ ql_elm_new(mapelm, u.ql_link);
arena_avail_tree_remove( ql_tail_insert(&mapelms, mapelm, u.ql_link);
&arena->runs_avail, mapelm);
mapelm->bits |= (CHUNK_MAP_LARGE |
CHUNK_MAP_ALLOCATED);
chunk->map[pageind + npages - 1].bits |=
(CHUNK_MAP_LARGE |
CHUNK_MAP_ALLOCATED);
arena->nactive += npages;
/*
* Append to list for later processing.
*/
ql_elm_new(mapelm, u.ql_link);
ql_tail_insert(&mapelms, mapelm,
u.ql_link);
break;
}
} }
pageind += npages; pageind += npages;
} else { } else {
/* Skip allocated run. */ /* Skip allocated run. */
if (mapelm->bits & CHUNK_MAP_LARGE) { if (mapelm->bits & CHUNK_MAP_LARGE) {
pageind += (mapelm->bits & CHUNK_MAP_PG_MASK) pageind += mapelm->bits >> PAGE_SHIFT;
>> CHUNK_MAP_PG_SHIFT;
} else { } else {
arena_run_t *run = (arena_run_t *)((uintptr_t) arena_run_t *run = (arena_run_t *)((uintptr_t)
chunk + (uintptr_t)(pageind << PAGE_SHIFT)); chunk + (uintptr_t)(pageind << PAGE_SHIFT));
assert((mapelm->bits & CHUNK_MAP_PG_MASK) == 0); assert((mapelm->bits >> PAGE_SHIFT) == 0);
assert(run->magic == ARENA_RUN_MAGIC); assert(run->magic == ARENA_RUN_MAGIC);
pageind += run->bin->run_size >> PAGE_SHIFT; pageind += run->bin->run_size >> PAGE_SHIFT;
} }
@ -609,48 +683,20 @@ arena_chunk_purge(arena_t *arena, arena_chunk_t *chunk)
nmadvise = 0; nmadvise = 0;
#endif #endif
ql_foreach(mapelm, &mapelms, u.ql_link) { ql_foreach(mapelm, &mapelms, u.ql_link) {
size_t i, j;
size_t pageind = ((uintptr_t)mapelm - (uintptr_t)chunk->map) / size_t pageind = ((uintptr_t)mapelm - (uintptr_t)chunk->map) /
sizeof(arena_chunk_map_t); sizeof(arena_chunk_map_t);
size_t npages = (mapelm->bits & CHUNK_MAP_PG_MASK) >> size_t npages = mapelm->bits >> PAGE_SHIFT;
CHUNK_MAP_PG_SHIFT;
assert(pageind + npages <= chunk_npages); assert(pageind + npages <= chunk_npages);
for (i = 0; i < npages;) {
if (chunk->map[pageind + i].bits & CHUNK_MAP_DIRTY) {
chunk->map[pageind + i].bits ^= CHUNK_MAP_DIRTY;
chunk->map[pageind + i].bits |=
(CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED);
/* Find adjacent dirty page(s). */
for (j = 1; i + j < npages; j++) {
if ((chunk->map[pageind + i + j].bits &
CHUNK_MAP_DIRTY) == 0)
break;
chunk->map[pageind + i + j].bits ^=
CHUNK_MAP_DIRTY;
chunk->map[pageind + i + j].bits |=
(CHUNK_MAP_LARGE |
CHUNK_MAP_ALLOCATED);
}
#ifdef JEMALLOC_DEBUG #ifdef JEMALLOC_DEBUG
assert(ndirty >= j); assert(ndirty >= npages);
ndirty -= j; ndirty -= npages;
#endif #endif
madvise((void *)((uintptr_t)chunk + (pageind << PAGE_SHIFT)),
madvise((void *)((uintptr_t)chunk + ((pageind + (npages << PAGE_SHIFT), MADV_DONTNEED);
i) << PAGE_SHIFT)), (j << PAGE_SHIFT),
MADV_DONTNEED);
#ifdef JEMALLOC_STATS #ifdef JEMALLOC_STATS
nmadvise++; nmadvise++;
#endif #endif
i += j;
} else {
chunk->map[pageind + i].bits |=
(CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED);
i++;
}
}
} }
#ifdef JEMALLOC_DEBUG #ifdef JEMALLOC_DEBUG
assert(ndirty == 0); assert(ndirty == 0);
@ -761,7 +807,8 @@ static void
arena_run_dalloc(arena_t *arena, arena_run_t *run, bool dirty) arena_run_dalloc(arena_t *arena, arena_run_t *run, bool dirty)
{ {
arena_chunk_t *chunk; arena_chunk_t *chunk;
size_t size, run_ind, run_pages; size_t size, run_ind, run_pages, flag_dirty;
arena_avail_tree_t *runs_avail;
chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(run); chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(run);
run_ind = (size_t)(((uintptr_t)run - (uintptr_t)chunk) run_ind = (size_t)(((uintptr_t)run - (uintptr_t)chunk)
@ -775,40 +822,35 @@ arena_run_dalloc(arena_t *arena, arena_run_t *run, bool dirty)
run_pages = (size >> PAGE_SHIFT); run_pages = (size >> PAGE_SHIFT);
arena->nactive -= run_pages; arena->nactive -= run_pages;
/*
* The run is dirty if the caller claims to have dirtied it, as well as
* if it was already dirty before being allocated.
*/
if ((chunk->map[run_ind].bits & CHUNK_MAP_DIRTY) != 0)
dirty = true;
flag_dirty = dirty ? CHUNK_MAP_DIRTY : 0;
runs_avail = dirty ? &arena->runs_avail_dirty :
&arena->runs_avail_clean;
/* Mark pages as unallocated in the chunk map. */ /* Mark pages as unallocated in the chunk map. */
if (dirty) { if (dirty) {
size_t i; chunk->map[run_ind].bits = size | flag_dirty;
chunk->map[run_ind+run_pages-1].bits = size | flag_dirty;
for (i = 0; i < run_pages; i++) { chunk->ndirty += run_pages;
/* arena->ndirty += run_pages;
* When (dirty == true), *all* pages within the run
* need to have their dirty bits set, because only
* small runs can create a mixture of clean/dirty
* pages, but such runs are passed to this function
* with (dirty == false).
*/
assert((chunk->map[run_ind + i].bits & CHUNK_MAP_DIRTY)
== 0);
chunk->ndirty++;
arena->ndirty++;
chunk->map[run_ind + i].bits = CHUNK_MAP_DIRTY;
}
} else { } else {
size_t i; chunk->map[run_ind].bits = size | (chunk->map[run_ind].bits &
CHUNK_MAP_ZEROED);
for (i = 0; i < run_pages; i++) { chunk->map[run_ind+run_pages-1].bits = size |
chunk->map[run_ind + i].bits &= ~(CHUNK_MAP_LARGE | (chunk->map[run_ind+run_pages-1].bits & CHUNK_MAP_ZEROED);
CHUNK_MAP_ALLOCATED);
}
} }
chunk->map[run_ind].bits = size | (chunk->map[run_ind].bits &
CHUNK_MAP_FLAGS_MASK);
chunk->map[run_ind+run_pages-1].bits = size |
(chunk->map[run_ind+run_pages-1].bits & CHUNK_MAP_FLAGS_MASK);
/* Try to coalesce forward. */ /* Try to coalesce forward. */
if (run_ind + run_pages < chunk_npages && if (run_ind + run_pages < chunk_npages &&
(chunk->map[run_ind+run_pages].bits & CHUNK_MAP_ALLOCATED) == 0) { (chunk->map[run_ind+run_pages].bits & CHUNK_MAP_ALLOCATED) == 0 &&
(chunk->map[run_ind+run_pages].bits & CHUNK_MAP_DIRTY) ==
flag_dirty) {
size_t nrun_size = chunk->map[run_ind+run_pages].bits & size_t nrun_size = chunk->map[run_ind+run_pages].bits &
~PAGE_MASK; ~PAGE_MASK;
@ -816,7 +858,7 @@ arena_run_dalloc(arena_t *arena, arena_run_t *run, bool dirty)
* Remove successor from runs_avail; the coalesced run is * Remove successor from runs_avail; the coalesced run is
* inserted later. * inserted later.
*/ */
arena_avail_tree_remove(&arena->runs_avail, arena_avail_tree_remove(runs_avail,
&chunk->map[run_ind+run_pages]); &chunk->map[run_ind+run_pages]);
size += nrun_size; size += nrun_size;
@ -833,7 +875,8 @@ arena_run_dalloc(arena_t *arena, arena_run_t *run, bool dirty)
/* Try to coalesce backward. */ /* Try to coalesce backward. */
if (run_ind > arena_chunk_header_npages && (chunk->map[run_ind-1].bits & if (run_ind > arena_chunk_header_npages && (chunk->map[run_ind-1].bits &
CHUNK_MAP_ALLOCATED) == 0) { CHUNK_MAP_ALLOCATED) == 0 && (chunk->map[run_ind-1].bits &
CHUNK_MAP_DIRTY) == flag_dirty) {
size_t prun_size = chunk->map[run_ind-1].bits & ~PAGE_MASK; size_t prun_size = chunk->map[run_ind-1].bits & ~PAGE_MASK;
run_ind -= prun_size >> PAGE_SHIFT; run_ind -= prun_size >> PAGE_SHIFT;
@ -842,8 +885,7 @@ arena_run_dalloc(arena_t *arena, arena_run_t *run, bool dirty)
* Remove predecessor from runs_avail; the coalesced run is * Remove predecessor from runs_avail; the coalesced run is
* inserted later. * inserted later.
*/ */
arena_avail_tree_remove(&arena->runs_avail, arena_avail_tree_remove(runs_avail, &chunk->map[run_ind]);
&chunk->map[run_ind]);
size += prun_size; size += prun_size;
run_pages = size >> PAGE_SHIFT; run_pages = size >> PAGE_SHIFT;
@ -857,7 +899,7 @@ arena_run_dalloc(arena_t *arena, arena_run_t *run, bool dirty)
} }
/* Insert into runs_avail, now that coalescing is complete. */ /* Insert into runs_avail, now that coalescing is complete. */
arena_avail_tree_insert(&arena->runs_avail, &chunk->map[run_ind]); arena_avail_tree_insert(runs_avail, &chunk->map[run_ind]);
/* /*
* Deallocate chunk if it is now completely unused. The bit * Deallocate chunk if it is now completely unused. The bit
@ -890,6 +932,7 @@ arena_run_trim_head(arena_t *arena, arena_chunk_t *chunk, arena_run_t *run,
{ {
size_t pageind = ((uintptr_t)run - (uintptr_t)chunk) >> PAGE_SHIFT; size_t pageind = ((uintptr_t)run - (uintptr_t)chunk) >> PAGE_SHIFT;
size_t head_npages = (oldsize - newsize) >> PAGE_SHIFT; size_t head_npages = (oldsize - newsize) >> PAGE_SHIFT;
size_t flags = chunk->map[pageind].bits & CHUNK_MAP_FLAGS_MASK;
assert(oldsize > newsize); assert(oldsize > newsize);
@ -897,12 +940,10 @@ arena_run_trim_head(arena_t *arena, arena_chunk_t *chunk, arena_run_t *run,
* Update the chunk map so that arena_run_dalloc() can treat the * Update the chunk map so that arena_run_dalloc() can treat the
* leading run as separately allocated. * leading run as separately allocated.
*/ */
assert((chunk->map[pageind].bits & CHUNK_MAP_DIRTY) == 0); assert(chunk->map[pageind].bits & CHUNK_MAP_LARGE);
chunk->map[pageind].bits = (oldsize - newsize) | CHUNK_MAP_LARGE | assert(chunk->map[pageind].bits & CHUNK_MAP_ALLOCATED);
CHUNK_MAP_ALLOCATED; chunk->map[pageind].bits = (oldsize - newsize) | flags;
assert((chunk->map[pageind+head_npages].bits & CHUNK_MAP_DIRTY) == 0); chunk->map[pageind+head_npages].bits = newsize | flags;
chunk->map[pageind+head_npages].bits = newsize | CHUNK_MAP_LARGE |
CHUNK_MAP_ALLOCATED;
arena_run_dalloc(arena, run, false); arena_run_dalloc(arena, run, false);
} }
@ -913,6 +954,7 @@ arena_run_trim_tail(arena_t *arena, arena_chunk_t *chunk, arena_run_t *run,
{ {
size_t pageind = ((uintptr_t)run - (uintptr_t)chunk) >> PAGE_SHIFT; size_t pageind = ((uintptr_t)run - (uintptr_t)chunk) >> PAGE_SHIFT;
size_t npages = newsize >> PAGE_SHIFT; size_t npages = newsize >> PAGE_SHIFT;
size_t flags = chunk->map[pageind].bits & CHUNK_MAP_FLAGS_MASK;
assert(oldsize > newsize); assert(oldsize > newsize);
@ -920,12 +962,11 @@ arena_run_trim_tail(arena_t *arena, arena_chunk_t *chunk, arena_run_t *run,
* Update the chunk map so that arena_run_dalloc() can treat the * Update the chunk map so that arena_run_dalloc() can treat the
* trailing run as separately allocated. * trailing run as separately allocated.
*/ */
assert((chunk->map[pageind].bits & CHUNK_MAP_DIRTY) == 0); assert(chunk->map[pageind].bits & CHUNK_MAP_LARGE);
chunk->map[pageind].bits = newsize | CHUNK_MAP_LARGE | assert(chunk->map[pageind].bits & CHUNK_MAP_ALLOCATED);
CHUNK_MAP_ALLOCATED; chunk->map[pageind].bits = newsize | flags;
assert((chunk->map[pageind+npages].bits & CHUNK_MAP_DIRTY) == 0); chunk->map[pageind+npages-1].bits = newsize | flags;
chunk->map[pageind+npages].bits = (oldsize - newsize) | CHUNK_MAP_LARGE chunk->map[pageind+npages].bits = (oldsize - newsize) | flags;
| CHUNK_MAP_ALLOCATED;
arena_run_dalloc(arena, (arena_run_t *)((uintptr_t)run + newsize), arena_run_dalloc(arena, (arena_run_t *)((uintptr_t)run + newsize),
dirty); dirty);
@ -950,7 +991,7 @@ arena_bin_nonfull_run_get(arena_t *arena, arena_bin_t *bin)
pageind = (((uintptr_t)mapelm - (uintptr_t)chunk->map) / pageind = (((uintptr_t)mapelm - (uintptr_t)chunk->map) /
sizeof(arena_chunk_map_t)); sizeof(arena_chunk_map_t));
run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind - run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind -
((mapelm->bits & CHUNK_MAP_PG_MASK) >> CHUNK_MAP_PG_SHIFT)) (mapelm->bits >> PAGE_SHIFT))
<< PAGE_SHIFT)); << PAGE_SHIFT));
#ifdef JEMALLOC_STATS #ifdef JEMALLOC_STATS
bin->stats.reruns++; bin->stats.reruns++;
@ -1005,7 +1046,7 @@ arena_bin_nonfull_run_get(arena_t *arena, arena_bin_t *bin)
pageind = (((uintptr_t)mapelm - (uintptr_t)chunk->map) / pageind = (((uintptr_t)mapelm - (uintptr_t)chunk->map) /
sizeof(arena_chunk_map_t)); sizeof(arena_chunk_map_t));
run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind - run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind -
((mapelm->bits & CHUNK_MAP_PG_MASK) >> CHUNK_MAP_PG_SHIFT)) (mapelm->bits >> PAGE_SHIFT))
<< PAGE_SHIFT)); << PAGE_SHIFT));
#ifdef JEMALLOC_STATS #ifdef JEMALLOC_STATS
bin->stats.reruns++; bin->stats.reruns++;
@ -1437,8 +1478,8 @@ arena_salloc(const void *ptr)
assert((mapbits & CHUNK_MAP_ALLOCATED) != 0); assert((mapbits & CHUNK_MAP_ALLOCATED) != 0);
if ((mapbits & CHUNK_MAP_LARGE) == 0) { if ((mapbits & CHUNK_MAP_LARGE) == 0) {
arena_run_t *run = (arena_run_t *)((uintptr_t)chunk + arena_run_t *run = (arena_run_t *)((uintptr_t)chunk +
(uintptr_t)((pageind - ((mapbits & CHUNK_MAP_PG_MASK) >> (uintptr_t)((pageind - (mapbits >> PAGE_SHIFT)) <<
CHUNK_MAP_PG_SHIFT)) << PAGE_SHIFT)); PAGE_SHIFT));
assert(run->magic == ARENA_RUN_MAGIC); assert(run->magic == ARENA_RUN_MAGIC);
assert(((uintptr_t)ptr - ((uintptr_t)run + assert(((uintptr_t)ptr - ((uintptr_t)run +
(uintptr_t)run->bin->reg0_offset)) % run->bin->reg_size == (uintptr_t)run->bin->reg0_offset)) % run->bin->reg_size ==
@ -1533,8 +1574,8 @@ arena_prof_cnt_get(const void *ptr)
assert((mapbits & CHUNK_MAP_ALLOCATED) != 0); assert((mapbits & CHUNK_MAP_ALLOCATED) != 0);
if ((mapbits & CHUNK_MAP_LARGE) == 0) { if ((mapbits & CHUNK_MAP_LARGE) == 0) {
arena_run_t *run = (arena_run_t *)((uintptr_t)chunk + arena_run_t *run = (arena_run_t *)((uintptr_t)chunk +
(uintptr_t)((pageind - ((mapbits & CHUNK_MAP_PG_MASK) >> (uintptr_t)((pageind - (mapbits >> PAGE_SHIFT)) <<
CHUNK_MAP_PG_SHIFT)) << PAGE_SHIFT)); PAGE_SHIFT));
arena_bin_t *bin = run->bin; arena_bin_t *bin = run->bin;
unsigned regind; unsigned regind;
@ -1564,8 +1605,8 @@ arena_prof_cnt_set(const void *ptr, prof_thr_cnt_t *cnt)
assert((mapbits & CHUNK_MAP_ALLOCATED) != 0); assert((mapbits & CHUNK_MAP_ALLOCATED) != 0);
if ((mapbits & CHUNK_MAP_LARGE) == 0) { if ((mapbits & CHUNK_MAP_LARGE) == 0) {
arena_run_t *run = (arena_run_t *)((uintptr_t)chunk + arena_run_t *run = (arena_run_t *)((uintptr_t)chunk +
(uintptr_t)((pageind - ((mapbits & CHUNK_MAP_PG_MASK) >> (uintptr_t)((pageind - (mapbits & >> PAGE_SHIFT)) <<
CHUNK_MAP_PG_SHIFT)) << PAGE_SHIFT)); PAGE_SHIFT));
arena_bin_t *bin = run->bin; arena_bin_t *bin = run->bin;
unsigned regind; unsigned regind;
@ -1584,9 +1625,9 @@ static void
arena_dalloc_bin_run(arena_t *arena, arena_chunk_t *chunk, arena_run_t *run, arena_dalloc_bin_run(arena_t *arena, arena_chunk_t *chunk, arena_run_t *run,
arena_bin_t *bin) arena_bin_t *bin)
{ {
size_t run_ind, past; size_t npages, run_ind, past;
/* Deallocate run. */ /* Dissociate run from bin. */
if (run == bin->runcur) if (run == bin->runcur)
bin->runcur = NULL; bin->runcur = NULL;
else if (bin->nregs != 1) { else if (bin->nregs != 1) {
@ -1600,29 +1641,38 @@ arena_dalloc_bin_run(arena_t *arena, arena_chunk_t *chunk, arena_run_t *run,
*/ */
arena_run_tree_remove(&bin->runs, run_mapelm); arena_run_tree_remove(&bin->runs, run_mapelm);
} }
/* Mark all pages that were ever used for allocations as dirty. */
run_ind = (size_t)(((uintptr_t)run - (uintptr_t)chunk) >> PAGE_SHIFT);
past = (size_t)(((uintptr_t)run->next - (uintptr_t)1U -
(uintptr_t)chunk) >> PAGE_SHIFT) + 1;
malloc_mutex_unlock(&bin->lock); malloc_mutex_unlock(&bin->lock);
/******************************/ /******************************/
npages = bin->run_size >> PAGE_SHIFT;
run_ind = (size_t)(((uintptr_t)run - (uintptr_t)chunk) >> PAGE_SHIFT);
past = (size_t)(((uintptr_t)run->next - (uintptr_t)1U -
(uintptr_t)chunk) >> PAGE_SHIFT) + 1;
malloc_mutex_lock(&arena->lock); malloc_mutex_lock(&arena->lock);
chunk->ndirty += past - run_ind;
arena->ndirty += past - run_ind; /*
for (; run_ind < past; run_ind++) { * If the run was originally clean, and some pages were never touched,
assert((chunk->map[run_ind].bits & CHUNK_MAP_DIRTY) == 0); * trim the clean pages before deallocating the dirty portion of the
chunk->map[run_ind].bits |= CHUNK_MAP_DIRTY; * run.
*/
if ((chunk->map[run_ind].bits & CHUNK_MAP_DIRTY) == 0 && past - run_ind
< npages) {
/*
* Trim clean pages. Convert to large run beforehand. Set the
* last map element first, in case this is a one-page run.
*/
chunk->map[run_ind+npages-1].bits = CHUNK_MAP_LARGE |
(chunk->map[run_ind].bits & CHUNK_MAP_FLAGS_MASK);
chunk->map[run_ind].bits = bin->run_size | CHUNK_MAP_LARGE |
(chunk->map[run_ind].bits & CHUNK_MAP_FLAGS_MASK);
arena_run_trim_tail(arena, chunk, run, (npages << PAGE_SHIFT),
((npages - (past - run_ind)) << PAGE_SHIFT), false);
npages = past - run_ind;
} }
#ifdef JEMALLOC_DEBUG #ifdef JEMALLOC_DEBUG
run->magic = 0; run->magic = 0;
#endif #endif
if (chunk->dirtied == false) { arena_run_dalloc(arena, run, true);
ql_tail_insert(&arena->chunks_dirty, chunk, link_dirty);
chunk->dirtied = true;
}
arena_run_dalloc(arena, run, false);
arena_maybe_purge(arena);
malloc_mutex_unlock(&arena->lock); malloc_mutex_unlock(&arena->lock);
/****************************/ /****************************/
malloc_mutex_lock(&bin->lock); malloc_mutex_lock(&bin->lock);
@ -1644,8 +1694,7 @@ arena_dalloc_bin(arena_t *arena, arena_chunk_t *chunk, void *ptr,
pageind = (((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT); pageind = (((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT);
run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind - run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind -
((mapelm->bits & CHUNK_MAP_PG_MASK) >> CHUNK_MAP_PG_SHIFT)) << (mapelm->bits >> PAGE_SHIFT)) << PAGE_SHIFT));
PAGE_SHIFT));
assert(run->magic == ARENA_RUN_MAGIC); assert(run->magic == ARENA_RUN_MAGIC);
bin = run->bin; bin = run->bin;
#if (defined(JEMALLOC_FILL) || defined(JEMALLOC_STATS)) #if (defined(JEMALLOC_FILL) || defined(JEMALLOC_STATS))
@ -2012,7 +2061,8 @@ arena_new(arena_t *arena, unsigned ind)
arena->ndirty = 0; arena->ndirty = 0;
arena->npurgatory = 0; arena->npurgatory = 0;
arena_avail_tree_new(&arena->runs_avail); arena_avail_tree_new(&arena->runs_avail_clean);
arena_avail_tree_new(&arena->runs_avail_dirty);
/* Initialize bins. */ /* Initialize bins. */
prev_run_size = PAGE_SIZE; prev_run_size = PAGE_SIZE;

View File

@ -314,8 +314,8 @@ tcache_destroy(tcache_t *tcache)
PAGE_SHIFT); PAGE_SHIFT);
arena_chunk_map_t *mapelm = &chunk->map[pageind]; arena_chunk_map_t *mapelm = &chunk->map[pageind];
arena_run_t *run = (arena_run_t *)((uintptr_t)chunk + arena_run_t *run = (arena_run_t *)((uintptr_t)chunk +
(uintptr_t)((pageind - ((mapelm->bits & CHUNK_MAP_PG_MASK) (uintptr_t)((pageind - (mapelm->bits >> PAGE_SHIFT)) <<
>> CHUNK_MAP_PG_SHIFT)) << PAGE_SHIFT)); PAGE_SHIFT));
arena_bin_t *bin = run->bin; arena_bin_t *bin = run->bin;
malloc_mutex_lock(&bin->lock); malloc_mutex_lock(&bin->lock);