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Diffstat (limited to 'include/jemalloc/internal/extent.h')
| -rw-r--r-- | include/jemalloc/internal/extent.h | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/include/jemalloc/internal/extent.h b/include/jemalloc/internal/extent.h new file mode 100644 index 000000000..1d51d4109 --- /dev/null +++ b/include/jemalloc/internal/extent.h @@ -0,0 +1,137 @@ +#ifndef JEMALLOC_INTERNAL_EXTENT_H +#define JEMALLOC_INTERNAL_EXTENT_H + +#include "jemalloc/internal/ecache.h" +#include "jemalloc/internal/ehooks.h" +#include "jemalloc/internal/ph.h" +#include "jemalloc/internal/rtree.h" + +/* + * This module contains the page-level allocator. It chooses the addresses that + * allocations requested by other modules will inhabit, and updates the global + * metadata to reflect allocation/deallocation/purging decisions. + */ + +/* + * When reuse (and split) an active extent, (1U << opt_lg_extent_max_active_fit) + * is the max ratio between the size of the active extent and the new extent. + */ +#define LG_EXTENT_MAX_ACTIVE_FIT_DEFAULT 6 +extern size_t opt_lg_extent_max_active_fit; + +edata_t *ecache_alloc(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, + ecache_t *ecache, edata_t *expand_edata, size_t size, size_t alignment, + bool zero, bool guarded); +edata_t *ecache_alloc_grow(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, + ecache_t *ecache, edata_t *expand_edata, size_t size, size_t alignment, + bool zero, bool guarded); +void ecache_dalloc(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, + ecache_t *ecache, edata_t *edata); +edata_t *ecache_evict(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, + ecache_t *ecache, size_t npages_min); + +void extent_gdump_add(tsdn_t *tsdn, const edata_t *edata); +void extent_record(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, ecache_t *ecache, + edata_t *edata); +void extent_dalloc_gap(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, + edata_t *edata); +edata_t *extent_alloc_wrapper(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, + void *new_addr, size_t size, size_t alignment, bool zero, bool *commit, + bool growing_retained); +void extent_dalloc_wrapper(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, + edata_t *edata); +void extent_destroy_wrapper(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, + edata_t *edata); +bool extent_commit_wrapper(tsdn_t *tsdn, ehooks_t *ehooks, edata_t *edata, + size_t offset, size_t length); +bool extent_decommit_wrapper(tsdn_t *tsdn, ehooks_t *ehooks, edata_t *edata, + size_t offset, size_t length); +bool extent_purge_lazy_wrapper(tsdn_t *tsdn, ehooks_t *ehooks, edata_t *edata, + size_t offset, size_t length); +bool extent_purge_forced_wrapper(tsdn_t *tsdn, ehooks_t *ehooks, edata_t *edata, + size_t offset, size_t length); +edata_t *extent_split_wrapper(tsdn_t *tsdn, pac_t *pac, + ehooks_t *ehooks, edata_t *edata, size_t size_a, size_t size_b, + bool holding_core_locks); +bool extent_merge_wrapper(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, + edata_t *a, edata_t *b); +bool extent_commit_zero(tsdn_t *tsdn, ehooks_t *ehooks, edata_t *edata, + bool commit, bool zero, bool growing_retained); +size_t extent_sn_next(pac_t *pac); +bool extent_boot(void); + +JEMALLOC_ALWAYS_INLINE bool +extent_neighbor_head_state_mergeable(bool edata_is_head, + bool neighbor_is_head, bool forward) { + /* + * Head states checking: disallow merging if the higher addr extent is a + * head extent. This helps preserve first-fit, and more importantly + * makes sure no merge across arenas. + */ + if (forward) { + if (neighbor_is_head) { + return false; + } + } else { + if (edata_is_head) { + return false; + } + } + return true; +} + +JEMALLOC_ALWAYS_INLINE bool +extent_can_acquire_neighbor(edata_t *edata, rtree_contents_t contents, + extent_pai_t pai, extent_state_t expected_state, bool forward, + bool expanding) { + edata_t *neighbor = contents.edata; + if (neighbor == NULL) { + return false; + } + /* It's not safe to access *neighbor yet; must verify states first. */ + bool neighbor_is_head = contents.metadata.is_head; + if (!extent_neighbor_head_state_mergeable(edata_is_head_get(edata), + neighbor_is_head, forward)) { + return false; + } + extent_state_t neighbor_state = contents.metadata.state; + if (pai == EXTENT_PAI_PAC) { + if (neighbor_state != expected_state) { + return false; + } + /* From this point, it's safe to access *neighbor. */ + if (!expanding && (edata_committed_get(edata) != + edata_committed_get(neighbor))) { + /* + * Some platforms (e.g. Windows) require an explicit + * commit step (and writing to uncommitted memory is not + * allowed). + */ + return false; + } + } else { + if (neighbor_state == extent_state_active) { + return false; + } + /* From this point, it's safe to access *neighbor. */ + } + + assert(edata_pai_get(edata) == pai); + if (edata_pai_get(neighbor) != pai) { + return false; + } + if (opt_retain) { + assert(edata_arena_ind_get(edata) == + edata_arena_ind_get(neighbor)); + } else { + if (edata_arena_ind_get(edata) != + edata_arena_ind_get(neighbor)) { + return false; + } + } + assert(!edata_guarded_get(edata) && !edata_guarded_get(neighbor)); + + return true; +} + +#endif /* JEMALLOC_INTERNAL_EXTENT_H */ |