77cccac8cd
This is part of a broader change to make header files better represent the dependencies between one another (see https://github.com/jemalloc/jemalloc/issues/533). It breaks up component headers into smaller parts that can be made to have a simpler dependency graph. For the autogenerated headers (smoothstep.h and size_classes.h), no splitting was necessary, so I didn't add support to emit multiple headers.
215 lines
6.5 KiB
C
215 lines
6.5 KiB
C
#ifndef JEMALLOC_INTERNAL_ARENA_STRUCTS_B_H
|
|
#define JEMALLOC_INTERNAL_ARENA_STRUCTS_B_H
|
|
/*
|
|
* Read-only information associated with each element of arena_t's bins array
|
|
* is stored separately, partly to reduce memory usage (only one copy, rather
|
|
* than one per arena), but mainly to avoid false cacheline sharing.
|
|
*
|
|
* Each slab has the following layout:
|
|
*
|
|
* /--------------------\
|
|
* | region 0 |
|
|
* |--------------------|
|
|
* | region 1 |
|
|
* |--------------------|
|
|
* | ... |
|
|
* | ... |
|
|
* | ... |
|
|
* |--------------------|
|
|
* | region nregs-1 |
|
|
* \--------------------/
|
|
*/
|
|
struct arena_bin_info_s {
|
|
/* Size of regions in a slab for this bin's size class. */
|
|
size_t reg_size;
|
|
|
|
/* Total size of a slab for this bin's size class. */
|
|
size_t slab_size;
|
|
|
|
/* Total number of regions in a slab for this bin's size class. */
|
|
uint32_t nregs;
|
|
|
|
/*
|
|
* Metadata used to manipulate bitmaps for slabs associated with this
|
|
* bin.
|
|
*/
|
|
bitmap_info_t bitmap_info;
|
|
};
|
|
|
|
struct arena_decay_s {
|
|
/*
|
|
* Approximate time in seconds from the creation of a set of unused
|
|
* dirty pages until an equivalent set of unused dirty pages is purged
|
|
* and/or reused.
|
|
*/
|
|
ssize_t time;
|
|
/* time / SMOOTHSTEP_NSTEPS. */
|
|
nstime_t interval;
|
|
/*
|
|
* Time at which the current decay interval logically started. We do
|
|
* not actually advance to a new epoch until sometime after it starts
|
|
* because of scheduling and computation delays, and it is even possible
|
|
* to completely skip epochs. In all cases, during epoch advancement we
|
|
* merge all relevant activity into the most recently recorded epoch.
|
|
*/
|
|
nstime_t epoch;
|
|
/* Deadline randomness generator. */
|
|
uint64_t jitter_state;
|
|
/*
|
|
* Deadline for current epoch. This is the sum of interval and per
|
|
* epoch jitter which is a uniform random variable in [0..interval).
|
|
* Epochs always advance by precise multiples of interval, but we
|
|
* randomize the deadline to reduce the likelihood of arenas purging in
|
|
* lockstep.
|
|
*/
|
|
nstime_t deadline;
|
|
/*
|
|
* Number of dirty pages at beginning of current epoch. During epoch
|
|
* advancement we use the delta between arena->decay.ndirty and
|
|
* arena->ndirty to determine how many dirty pages, if any, were
|
|
* generated.
|
|
*/
|
|
size_t nunpurged;
|
|
/*
|
|
* Trailing log of how many unused dirty pages were generated during
|
|
* each of the past SMOOTHSTEP_NSTEPS decay epochs, where the last
|
|
* element is the most recent epoch. Corresponding epoch times are
|
|
* relative to epoch.
|
|
*/
|
|
size_t backlog[SMOOTHSTEP_NSTEPS];
|
|
};
|
|
|
|
struct arena_bin_s {
|
|
/* All operations on arena_bin_t fields require lock ownership. */
|
|
malloc_mutex_t lock;
|
|
|
|
/*
|
|
* Current slab being used to service allocations of this bin's size
|
|
* class. slabcur is independent of slabs_{nonfull,full}; whenever
|
|
* slabcur is reassigned, the previous slab must be deallocated or
|
|
* inserted into slabs_{nonfull,full}.
|
|
*/
|
|
extent_t *slabcur;
|
|
|
|
/*
|
|
* Heap of non-full slabs. This heap is used to assure that new
|
|
* allocations come from the non-full slab that is oldest/lowest in
|
|
* memory.
|
|
*/
|
|
extent_heap_t slabs_nonfull;
|
|
|
|
/* Ring sentinel used to track full slabs. */
|
|
extent_t slabs_full;
|
|
|
|
/* Bin statistics. */
|
|
malloc_bin_stats_t stats;
|
|
};
|
|
|
|
struct arena_s {
|
|
/*
|
|
* Number of threads currently assigned to this arena, synchronized via
|
|
* atomic operations. Each thread has two distinct assignments, one for
|
|
* application-serving allocation, and the other for internal metadata
|
|
* allocation. Internal metadata must not be allocated from arenas
|
|
* explicitly created via the arenas.create mallctl, because the
|
|
* arena.<i>.reset mallctl indiscriminately discards all allocations for
|
|
* the affected arena.
|
|
*
|
|
* 0: Application allocation.
|
|
* 1: Internal metadata allocation.
|
|
*/
|
|
unsigned nthreads[2];
|
|
|
|
/*
|
|
* There are three classes of arena operations from a locking
|
|
* perspective:
|
|
* 1) Thread assignment (modifies nthreads) is synchronized via atomics.
|
|
* 2) Bin-related operations are protected by bin locks.
|
|
* 3) Extent-related operations are protected by this mutex.
|
|
*/
|
|
malloc_mutex_t lock;
|
|
|
|
arena_stats_t stats;
|
|
/*
|
|
* List of tcaches for extant threads associated with this arena.
|
|
* Stats from these are merged incrementally, and at exit if
|
|
* opt_stats_print is enabled.
|
|
*/
|
|
ql_head(tcache_t) tcache_ql;
|
|
|
|
uint64_t prof_accumbytes;
|
|
|
|
/*
|
|
* PRNG state for cache index randomization of large allocation base
|
|
* pointers.
|
|
*/
|
|
size_t offset_state;
|
|
|
|
/* Extent serial number generator state. */
|
|
size_t extent_sn_next;
|
|
|
|
dss_prec_t dss_prec;
|
|
|
|
/* True if a thread is currently executing arena_purge_to_limit(). */
|
|
bool purging;
|
|
|
|
/* Number of pages in active extents. */
|
|
size_t nactive;
|
|
|
|
/*
|
|
* Current count of pages within unused extents that are potentially
|
|
* dirty, and for which pages_purge_*() has not been called. By
|
|
* tracking this, we can institute a limit on how much dirty unused
|
|
* memory is mapped for each arena.
|
|
*/
|
|
size_t ndirty;
|
|
|
|
/* Decay-based purging state. */
|
|
arena_decay_t decay;
|
|
|
|
/* Extant large allocations. */
|
|
ql_head(extent_t) large;
|
|
/* Synchronizes all large allocation/update/deallocation. */
|
|
malloc_mutex_t large_mtx;
|
|
|
|
/*
|
|
* Heaps of extents that were previously allocated. These are used when
|
|
* allocating extents, in an attempt to re-use address space.
|
|
*/
|
|
extent_heap_t extents_cached[NPSIZES+1];
|
|
extent_heap_t extents_retained[NPSIZES+1];
|
|
/*
|
|
* Ring sentinel used to track unused dirty memory. Dirty memory is
|
|
* managed as an LRU of cached extents.
|
|
*/
|
|
extent_t extents_dirty;
|
|
/* Protects extents_{cached,retained,dirty}. */
|
|
malloc_mutex_t extents_mtx;
|
|
|
|
/*
|
|
* Next extent size class in a growing series to use when satisfying a
|
|
* request via the extent hooks (only if !config_munmap). This limits
|
|
* the number of disjoint virtual memory ranges so that extent merging
|
|
* can be effective even if multiple arenas' extent allocation requests
|
|
* are highly interleaved.
|
|
*/
|
|
pszind_t extent_grow_next;
|
|
|
|
/* Cache of extent structures that were allocated via base_alloc(). */
|
|
ql_head(extent_t) extent_cache;
|
|
malloc_mutex_t extent_cache_mtx;
|
|
|
|
/* bins is used to store heaps of free regions. */
|
|
arena_bin_t bins[NBINS];
|
|
|
|
/* Base allocator, from which arena metadata are allocated. */
|
|
base_t *base;
|
|
};
|
|
|
|
/* Used in conjunction with tsd for fast arena-related context lookup. */
|
|
struct arena_tdata_s {
|
|
ticker_t decay_ticker;
|
|
};
|
|
|
|
#endif /* JEMALLOC_INTERNAL_ARENA_STRUCTS_B_H */
|