server-skynet-source-3rd-je.../include/jemalloc/internal/psset.h
David Goldblatt 43af63fff4 HPA: Manage whole hugepages at a time.
This redesigns the HPA implementation to allow us to manage hugepages all at
once, locally, without relying on a global fallback.
2020-12-07 06:21:08 -08:00

95 lines
3.0 KiB
C

#ifndef JEMALLOC_INTERNAL_PSSET_H
#define JEMALLOC_INTERNAL_PSSET_H
/*
* A page-slab set. What the eset is to PAC, the psset is to HPA. It maintains
* a collection of page-slabs (the intent being that they are backed by
* hugepages, or at least could be), and handles allocation and deallocation
* requests.
*
* It has the same synchronization guarantees as the eset; stats queries don't
* need any external synchronization, everything else does.
*/
/*
* One more than the maximum pszind_t we will serve out of the HPA.
* Practically, we expect only the first few to be actually used. This
* corresponds to a maximum size of of 512MB on systems with 4k pages and
* SC_NGROUP == 4, which is already an unreasonably large maximum. Morally, you
* can think of this as being SC_NPSIZES, but there's no sense in wasting that
* much space in the arena, making bitmaps that much larger, etc.
*/
#define PSSET_NPSIZES 64
typedef struct psset_bin_stats_s psset_bin_stats_t;
struct psset_bin_stats_s {
/* How many pageslabs are in this bin? */
size_t npageslabs_huge;
size_t npageslabs_nonhuge;
/* Of them, how many pages are active? */
size_t nactive_huge;
size_t nactive_nonhuge;
/* How many are inactive? */
size_t ninactive_huge;
size_t ninactive_nonhuge;
};
/* Used only by CTL; not actually stored here (i.e., all derived). */
typedef struct psset_stats_s psset_stats_t;
struct psset_stats_s {
/*
* Full slabs don't live in any edata heap. But we still track their
* stats.
*/
psset_bin_stats_t full_slabs;
psset_bin_stats_t nonfull_slabs[PSSET_NPSIZES];
};
typedef struct psset_s psset_t;
struct psset_s {
/*
* The pageslabs, quantized by the size class of the largest contiguous
* free run of pages in a pageslab.
*/
edata_age_heap_t pageslabs[PSSET_NPSIZES];
bitmap_t bitmap[BITMAP_GROUPS(PSSET_NPSIZES)];
psset_stats_t stats;
/* How many alloc_new calls have happened? */
uint64_t age_counter;
};
void psset_init(psset_t *psset);
void psset_stats_accum(psset_stats_t *dst, psset_stats_t *src);
void psset_insert(psset_t *psset, edata_t *ps);
void psset_remove(psset_t *psset, edata_t *ps);
void psset_hugify(psset_t *psset, edata_t *ps);
/*
* Tries to obtain a chunk from an existing pageslab already in the set.
* Returns true on failure.
*/
bool psset_alloc_reuse(psset_t *psset, edata_t *r_edata, size_t size);
/*
* Given a newly created pageslab ps (not currently in the set), pass ownership
* to the psset and allocate an extent from within it. The passed-in pageslab
* must be at least as big as size.
*/
void psset_alloc_new(psset_t *psset, edata_t *ps,
edata_t *r_edata, size_t size);
/*
* Given an extent that comes from a pageslab in this pageslab set, returns it
* to its slab. Does not take ownership of the underlying edata_t.
*
* If some slab becomes empty as a result of the dalloc, it is retuend -- the
* result must be checked and deallocated to the central HPA. Otherwise returns
* NULL.
*/
edata_t *psset_dalloc(psset_t *psset, edata_t *edata);
#endif /* JEMALLOC_INTERNAL_PSSET_H */