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#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_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 */
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