Fix and refactor runs_dirty-based purging.
Fix runs_dirty-based purging to also purge dirty pages in the spare chunk. Refactor runs_dirty manipulation into arena_dirty_{insert,remove}(), and move the arena->ndirty accounting into those functions. Remove the u.ql_link field from arena_chunk_map_t, and get rid of the enclosing union for u.rb_link, since only rb_link remains. Remove the ndirty field from arena_chunk_t.
This commit is contained in:
parent
e8a2fd83a2
commit
070b3c3fbd
@ -65,23 +65,14 @@ struct arena_chunk_map_s {
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*/
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union {
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#endif
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union {
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/*
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* Linkage for run trees. There are two disjoint uses:
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*
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* 1) arena_t's runs_avail tree.
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* 2) arena_run_t conceptually uses this linkage for in-use
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* non-full runs, rather than directly embedding linkage.
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* 2) arena_run_t conceptually uses this linkage for in-use non-full
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* runs, rather than directly embedding linkage.
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*/
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rb_node(arena_chunk_map_t) rb_link;
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/*
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* List of runs currently in purgatory. arena_chunk_purge()
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* temporarily allocates runs that contain dirty pages while
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* purging, so that other threads cannot use the runs while the
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* purging thread is operating without the arena lock held.
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*/
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ql_elm(arena_chunk_map_t) ql_link;
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} u;
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/* Profile counters, used for large object runs. */
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prof_ctx_t *prof_ctx;
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@ -167,9 +158,6 @@ struct arena_chunk_s {
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/* Arena that owns the chunk. */
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arena_t *arena;
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/* Number of dirty pages. */
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size_t ndirty;
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/*
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* Map of pages within chunk that keeps track of free/large/small. The
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* first map_bias entries are omitted, since the chunk header does not
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@ -317,9 +305,6 @@ struct arena_s {
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dss_prec_t dss_prec;
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/* List of dirty runs this arena manages. */
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arena_chunk_mapelms_t runs_dirty;
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/*
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* In order to avoid rapid chunk allocation/deallocation when an arena
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* oscillates right on the cusp of needing a new chunk, cache the most
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@ -349,6 +334,9 @@ struct arena_s {
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*/
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arena_avail_tree_t runs_avail;
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/* List of dirty runs this arena manages. */
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arena_chunk_mapelms_t runs_dirty;
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/*
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* user-configureable chunk allocation and deallocation functions.
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*/
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184
src/arena.c
184
src/arena.c
@ -90,7 +90,7 @@ arena_run_comp(arena_chunk_map_t *a, arena_chunk_map_t *b)
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/* Generate red-black tree functions. */
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rb_gen(static UNUSED, arena_run_tree_, arena_run_tree_t, arena_chunk_map_t,
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u.rb_link, arena_run_comp)
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rb_link, arena_run_comp)
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static inline int
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arena_avail_comp(arena_chunk_map_t *a, arena_chunk_map_t *b)
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@ -123,7 +123,7 @@ arena_avail_comp(arena_chunk_map_t *a, arena_chunk_map_t *b)
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/* Generate red-black tree functions. */
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rb_gen(static UNUSED, arena_avail_tree_, arena_avail_tree_t, arena_chunk_map_t,
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u.rb_link, arena_avail_comp)
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rb_link, arena_avail_comp)
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static void
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arena_avail_insert(arena_t *arena, arena_chunk_t *chunk, size_t pageind,
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@ -132,12 +132,6 @@ arena_avail_insert(arena_t *arena, arena_chunk_t *chunk, size_t pageind,
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assert(npages == (arena_mapbits_unallocated_size_get(chunk, pageind) >>
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LG_PAGE));
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if (arena_mapbits_dirty_get(chunk, pageind) != 0) {
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arena->ndirty += npages;
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chunk->ndirty += npages;
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}
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arena_avail_tree_insert(&arena->runs_avail, arena_mapp_get(chunk,
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pageind));
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}
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@ -149,16 +143,39 @@ arena_avail_remove(arena_t *arena, arena_chunk_t *chunk, size_t pageind,
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assert(npages == (arena_mapbits_unallocated_size_get(chunk, pageind) >>
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LG_PAGE));
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if (arena_mapbits_dirty_get(chunk, pageind) != 0) {
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arena->ndirty -= npages;
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chunk->ndirty -= npages;
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}
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arena_avail_tree_remove(&arena->runs_avail, arena_mapp_get(chunk,
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pageind));
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}
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static void
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arena_dirty_insert(arena_t *arena, arena_chunk_t *chunk, size_t pageind,
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size_t npages)
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{
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arena_chunk_map_t *mapelm = arena_mapp_get(chunk, pageind);
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assert(npages == (arena_mapbits_unallocated_size_get(chunk, pageind) >>
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LG_PAGE));
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assert(arena_mapbits_dirty_get(chunk, pageind) == CHUNK_MAP_DIRTY);
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assert(arena_mapbits_dirty_get(chunk, pageind+npages-1) ==
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CHUNK_MAP_DIRTY);
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ql_elm_new(mapelm, dr_link);
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ql_tail_insert(&arena->runs_dirty, mapelm, dr_link);
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arena->ndirty += npages;
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}
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static void
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arena_dirty_remove(arena_t *arena, arena_chunk_t *chunk, size_t pageind,
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size_t npages)
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{
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arena_chunk_map_t *mapelm = arena_mapp_get(chunk, pageind);
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assert(npages == (arena_mapbits_unallocated_size_get(chunk, pageind) >>
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LG_PAGE));
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assert(arena_mapbits_dirty_get(chunk, pageind) == CHUNK_MAP_DIRTY);
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assert(arena_mapbits_dirty_get(chunk, pageind+npages-1) ==
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CHUNK_MAP_DIRTY);
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ql_remove(&arena->runs_dirty, mapelm, dr_link);
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arena->ndirty -= npages;
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}
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static inline void *
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arena_run_reg_alloc(arena_run_t *run, arena_bin_info_t *bin_info)
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{
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@ -252,7 +269,6 @@ static void
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arena_run_split_remove(arena_t *arena, arena_chunk_t *chunk, size_t run_ind,
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size_t flag_dirty, size_t need_pages)
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{
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arena_chunk_map_t *mapelm;
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size_t total_pages, rem_pages;
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total_pages = arena_mapbits_unallocated_size_get(chunk, run_ind) >>
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@ -263,11 +279,8 @@ arena_run_split_remove(arena_t *arena, arena_chunk_t *chunk, size_t run_ind,
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rem_pages = total_pages - need_pages;
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arena_avail_remove(arena, chunk, run_ind, total_pages);
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if (flag_dirty != 0) {
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/* If the run is dirty, it must be in the dirty list. */
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mapelm = arena_mapp_get(chunk, run_ind);
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ql_remove(&arena->runs_dirty, mapelm, dr_link);
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}
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if (flag_dirty != 0)
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arena_dirty_remove(arena, chunk, run_ind, total_pages);
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arena_cactive_update(arena, need_pages, 0);
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arena->nactive += need_pages;
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@ -280,14 +293,8 @@ arena_run_split_remove(arena_t *arena, arena_chunk_t *chunk, size_t run_ind,
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arena_mapbits_unallocated_set(chunk,
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run_ind+total_pages-1, (rem_pages << LG_PAGE),
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flag_dirty);
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mapelm = arena_mapp_get(chunk, run_ind+need_pages);
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/*
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* Append the trailing run at the end of the dirty list.
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* We could also insert the run at the original place.
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* Let us consider this later.
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*/
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ql_elm_new(mapelm, dr_link);
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ql_tail_insert(&arena->runs_dirty, mapelm, dr_link);
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arena_dirty_insert(arena, chunk, run_ind+need_pages,
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rem_pages);
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} else {
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arena_mapbits_unallocated_set(chunk, run_ind+need_pages,
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(rem_pages << LG_PAGE),
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@ -512,11 +519,6 @@ arena_chunk_init_hard(arena_t *arena)
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chunk->arena = arena;
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/*
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* Claim that no pages are in use, since the header is merely overhead.
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*/
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chunk->ndirty = 0;
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/*
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* Initialize the map to contain one maximal free untouched run. Mark
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* the pages as zeroed iff chunk_alloc() returned a zeroed chunk.
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@ -568,11 +570,6 @@ arena_chunk_alloc(arena_t *arena)
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/* Insert the run into the runs_avail tree. */
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arena_avail_insert(arena, chunk, map_bias, chunk_npages-map_bias);
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if (arena_mapbits_dirty_get(chunk, map_bias) != 0) {
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arena_chunk_map_t *mapelm = arena_mapp_get(chunk, map_bias);
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ql_elm_new(mapelm, dr_link);
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ql_tail_insert(&arena->runs_dirty, mapelm, dr_link);
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}
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return (chunk);
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}
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@ -626,15 +623,15 @@ arena_chunk_dalloc(arena_t *arena, arena_chunk_t *chunk)
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* it.
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*/
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arena_avail_remove(arena, chunk, map_bias, chunk_npages-map_bias);
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if (arena_mapbits_dirty_get(chunk, map_bias) != 0) {
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arena_chunk_map_t *mapelm = arena_mapp_get(chunk, map_bias);
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ql_remove(&arena->runs_dirty, mapelm, dr_link);
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}
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if (arena->spare != NULL) {
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arena_chunk_t *spare = arena->spare;
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arena->spare = chunk;
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if (arena_mapbits_dirty_get(spare, map_bias) != 0) {
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arena_dirty_remove(arena, spare, map_bias,
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chunk_npages-map_bias);
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}
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arena_chunk_dalloc_internal(arena, spare);
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} else
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arena->spare = chunk;
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@ -752,18 +749,17 @@ arena_run_alloc_small(arena_t *arena, size_t size, size_t binind)
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static inline void
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arena_maybe_purge(arena_t *arena)
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{
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size_t npurgeable, threshold;
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size_t threshold;
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/* Don't purge if the option is disabled. */
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if (opt_lg_dirty_mult < 0)
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return;
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npurgeable = arena->ndirty;
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threshold = (arena->nactive >> opt_lg_dirty_mult);
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/*
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* Don't purge unless the number of purgeable pages exceeds the
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* threshold.
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*/
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if (npurgeable <= threshold)
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if (arena->ndirty <= threshold)
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return;
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arena_purge(arena, false);
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@ -792,50 +788,53 @@ arena_dirty_count(arena_t *arena)
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}
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static size_t
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arena_compute_npurgatory(arena_t *arena, bool all)
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arena_compute_npurge(arena_t *arena, bool all)
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{
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size_t npurgatory, npurgeable;
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size_t npurge;
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/*
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* Compute the minimum number of pages that this thread should try to
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* purge.
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*/
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npurgeable = arena->ndirty;
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if (all == false) {
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size_t threshold = (arena->nactive >> opt_lg_dirty_mult);
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npurgatory = npurgeable - threshold;
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npurge = arena->ndirty - threshold;
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} else
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npurgatory = npurgeable;
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npurge = arena->ndirty;
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return (npurgatory);
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return (npurge);
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}
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static size_t
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arena_stash_dirty(arena_t *arena, bool all, size_t npurgatory,
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arena_stash_dirty(arena_t *arena, bool all, size_t npurge,
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arena_chunk_mapelms_t *mapelms)
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{
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arena_chunk_map_t *mapelm;
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size_t nstashed = 0;
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arena_chunk_t *chunk;
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size_t pageind, npages, run_size;
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arena_run_t *run;
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/* Add at least npurgatory pages to purge_list. */
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/* Add at least npurge pages to purge_list. */
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for (mapelm = ql_first(&arena->runs_dirty); mapelm != NULL;
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mapelm = ql_first(&arena->runs_dirty)) {
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chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(mapelm);
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pageind = arena_mapelm_to_pageind(mapelm);
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run_size = arena_mapbits_unallocated_size_get(chunk, pageind);
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npages = run_size >> LG_PAGE;
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run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)(pageind <<
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LG_PAGE));
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arena_chunk_t *chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(mapelm);
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size_t pageind = arena_mapelm_to_pageind(mapelm);
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size_t run_size = arena_mapbits_unallocated_size_get(chunk,
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pageind);
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size_t npages = run_size >> LG_PAGE;
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arena_run_t *run = (arena_run_t *)((uintptr_t)chunk +
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(uintptr_t)(pageind << LG_PAGE));
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assert(pageind + npages <= chunk_npages);
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assert(arena_mapbits_dirty_get(chunk, pageind) ==
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arena_mapbits_dirty_get(chunk, pageind+npages-1));
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/*
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* If purging the spare chunk's run, make it available prior to
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* allocation.
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*/
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if (chunk == arena->spare)
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arena_chunk_alloc(arena);
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/* Temporarily allocate the free dirty run. */
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arena_run_split_large(arena, run, run_size, false);
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/* Append to purge_list for later processing. */
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@ -844,7 +843,7 @@ arena_stash_dirty(arena_t *arena, bool all, size_t npurgatory,
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nstashed += npages;
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if (all == false && nstashed >= npurgatory)
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if (all == false && nstashed >= npurge)
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break;
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}
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@ -856,8 +855,6 @@ arena_purge_stashed(arena_t *arena, arena_chunk_mapelms_t *mapelms)
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{
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size_t npurged, nmadvise;
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arena_chunk_map_t *mapelm;
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arena_chunk_t *chunk;
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size_t pageind, npages, run_size;
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if (config_stats)
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nmadvise = 0;
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@ -866,8 +863,9 @@ arena_purge_stashed(arena_t *arena, arena_chunk_mapelms_t *mapelms)
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malloc_mutex_unlock(&arena->lock);
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ql_foreach(mapelm, mapelms, dr_link) {
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arena_chunk_t *chunk;
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size_t pageind, run_size, npages, flag_unzeroed, i;
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bool unzeroed;
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size_t flag_unzeroed, i;
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chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(mapelm);
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pageind = arena_mapelm_to_pageind(mapelm);
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@ -913,17 +911,14 @@ static void
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arena_unstash_purged(arena_t *arena, arena_chunk_mapelms_t *mapelms)
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{
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arena_chunk_map_t *mapelm;
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arena_chunk_t *chunk;
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arena_run_t *run;
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size_t pageind;
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/* Deallocate runs. */
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for (mapelm = ql_first(mapelms); mapelm != NULL;
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mapelm = ql_first(mapelms)) {
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chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(mapelm);
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pageind = arena_mapelm_to_pageind(mapelm);
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run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)(pageind <<
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LG_PAGE));
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arena_chunk_t *chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(mapelm);
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size_t pageind = arena_mapelm_to_pageind(mapelm);
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arena_run_t *run = (arena_run_t *)((uintptr_t)chunk +
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(uintptr_t)(pageind << LG_PAGE));
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ql_remove(mapelms, mapelm, dr_link);
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arena_run_dalloc(arena, run, false, true);
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}
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@ -932,7 +927,7 @@ arena_unstash_purged(arena_t *arena, arena_chunk_mapelms_t *mapelms)
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void
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arena_purge(arena_t *arena, bool all)
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{
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size_t npurgatory, npurgeable, npurged;
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size_t npurge, npurgeable, npurged;
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arena_chunk_mapelms_t purge_list;
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if (config_debug) {
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@ -944,21 +939,12 @@ arena_purge(arena_t *arena, bool all)
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if (config_stats)
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arena->stats.npurge++;
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/*
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* Add the minimum number of pages this thread should try to purge to
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* arena->npurgatory. This will keep multiple threads from racing to
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* reduce ndirty below the threshold.
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*/
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npurgatory = arena_compute_npurgatory(arena, all);
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npurge = arena_compute_npurge(arena, all);
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ql_new(&purge_list);
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npurgeable = arena_stash_dirty(arena, all, npurgatory, &purge_list);
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assert(npurgeable >= npurgatory);
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npurgeable = arena_stash_dirty(arena, all, npurge, &purge_list);
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assert(npurgeable >= npurge);
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npurged = arena_purge_stashed(arena, &purge_list);
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assert(npurged == npurgeable);
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arena_unstash_purged(arena, &purge_list);
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}
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@ -999,9 +985,8 @@ arena_run_coalesce(arena_t *arena, arena_chunk_t *chunk, size_t *p_size,
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/* If the successor is dirty, remove it from runs_dirty. */
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if (flag_dirty != 0) {
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arena_chunk_map_t *mapelm = arena_mapp_get(chunk,
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run_ind+run_pages);
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ql_remove(&arena->runs_dirty, mapelm, dr_link);
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arena_dirty_remove(arena, chunk, run_ind+run_pages,
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nrun_pages);
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}
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size += nrun_size;
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||||
@ -1032,11 +1017,8 @@ arena_run_coalesce(arena_t *arena, arena_chunk_t *chunk, size_t *p_size,
|
||||
arena_avail_remove(arena, chunk, run_ind, prun_pages);
|
||||
|
||||
/* If the predecessor is dirty, remove it from runs_dirty. */
|
||||
if (flag_dirty != 0) {
|
||||
arena_chunk_map_t *mapelm = arena_mapp_get(chunk,
|
||||
run_ind);
|
||||
ql_remove(&arena->runs_dirty, mapelm, dr_link);
|
||||
}
|
||||
if (flag_dirty != 0)
|
||||
arena_dirty_remove(arena, chunk, run_ind, prun_pages);
|
||||
|
||||
size += prun_size;
|
||||
run_pages += prun_pages;
|
||||
@ -1055,7 +1037,6 @@ static void
|
||||
arena_run_dalloc(arena_t *arena, arena_run_t *run, bool dirty, bool cleaned)
|
||||
{
|
||||
arena_chunk_t *chunk;
|
||||
arena_chunk_map_t *mapelm;
|
||||
size_t size, run_ind, run_pages, flag_dirty;
|
||||
|
||||
chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(run);
|
||||
@ -1110,12 +1091,8 @@ arena_run_dalloc(arena_t *arena, arena_run_t *run, bool dirty, bool cleaned)
|
||||
arena_mapbits_dirty_get(chunk, run_ind+run_pages-1));
|
||||
arena_avail_insert(arena, chunk, run_ind, run_pages);
|
||||
|
||||
if (dirty) {
|
||||
/* Insert into runs_dirty list. */
|
||||
mapelm = arena_mapp_get(chunk, run_ind);
|
||||
ql_elm_new(mapelm, dr_link);
|
||||
ql_tail_insert(&arena->runs_dirty, mapelm, dr_link);
|
||||
}
|
||||
if (dirty)
|
||||
arena_dirty_insert(arena, chunk, run_ind, run_pages);
|
||||
|
||||
/* Deallocate chunk if it is now completely unused. */
|
||||
if (size == arena_maxclass) {
|
||||
@ -2237,14 +2214,13 @@ arena_new(arena_t *arena, unsigned ind)
|
||||
|
||||
arena->dss_prec = chunk_dss_prec_get();
|
||||
|
||||
/* Initialize chunks. */
|
||||
ql_new(&arena->runs_dirty);
|
||||
arena->spare = NULL;
|
||||
|
||||
arena->nactive = 0;
|
||||
arena->ndirty = 0;
|
||||
|
||||
arena_avail_tree_new(&arena->runs_avail);
|
||||
ql_new(&arena->runs_dirty);
|
||||
|
||||
/* Initialize bins. */
|
||||
for (i = 0; i < NBINS; i++) {
|
||||
|
Loading…
Reference in New Issue
Block a user