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#ifndef JEMALLOC_INTERNAL_PSSET_H
#define JEMALLOC_INTERNAL_PSSET_H
#include "jemalloc/internal/hpdata.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.
*/
/*
* 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
/*
* We keep two purge lists per page size class; one for hugified hpdatas (at
* index 2*pszind), and one for the non-hugified hpdatas (at index 2*pszind +
* 1). This lets us implement a preference for purging non-hugified hpdatas
* among similarly-dirty ones.
* We reserve the last two indices for empty slabs, in that case purging
* hugified ones (which are definitionally all waste) before non-hugified ones
* (i.e. reversing the order).
*/
#define PSSET_NPURGE_LISTS (2 * PSSET_NPSIZES)
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;
/* Of them, how many pages are active? */
size_t nactive;
/* And how many are dirty? */
size_t ndirty;
};
typedef struct psset_stats_s psset_stats_t;
struct psset_stats_s {
/*
* The second index is huge stats; nonfull_slabs[pszind][0] contains
* stats for the non-huge slabs in bucket pszind, while
* nonfull_slabs[pszind][1] contains stats for the huge slabs.
*/
psset_bin_stats_t nonfull_slabs[PSSET_NPSIZES][2];
/*
* Full slabs don't live in any edata heap, but we still track their
* stats.
*/
psset_bin_stats_t full_slabs[2];
/* Empty slabs are similar. */
psset_bin_stats_t empty_slabs[2];
};
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.
*/
hpdata_age_heap_t pageslabs[PSSET_NPSIZES];
/* Bitmap for which set bits correspond to non-empty heaps. */
fb_group_t pageslab_bitmap[FB_NGROUPS(PSSET_NPSIZES)];
/*
* The sum of all bin stats in stats. This lets us quickly answer
* queries for the number of dirty, active, and retained pages in the
* entire set.
*/
psset_bin_stats_t merged_stats;
psset_stats_t stats;
/*
* Slabs with no active allocations, but which are allowed to serve new
* allocations.
*/
hpdata_empty_list_t empty;
/*
* Slabs which are available to be purged, ordered by how much we want
* to purge them (with later indices indicating slabs we want to purge
* more).
*/
hpdata_purge_list_t to_purge[PSSET_NPURGE_LISTS];
/* Bitmap for which set bits correspond to non-empty purge lists. */
fb_group_t purge_bitmap[FB_NGROUPS(PSSET_NPURGE_LISTS)];
/* Slabs which are available to be hugified. */
hpdata_hugify_list_t to_hugify;
};
void psset_init(psset_t *psset);
void psset_stats_accum(psset_stats_t *dst, psset_stats_t *src);
/*
* Begin or end updating the given pageslab's metadata. While the pageslab is
* being updated, it won't be returned from psset_fit calls.
*/
void psset_update_begin(psset_t *psset, hpdata_t *ps);
void psset_update_end(psset_t *psset, hpdata_t *ps);
/* Analogous to the eset_fit; pick a hpdata to serve the request. */
hpdata_t *psset_pick_alloc(psset_t *psset, size_t size);
/* Pick one to purge. */
hpdata_t *psset_pick_purge(psset_t *psset);
/* Pick one to hugify. */
hpdata_t *psset_pick_hugify(psset_t *psset);
void psset_insert(psset_t *psset, hpdata_t *ps);
void psset_remove(psset_t *psset, hpdata_t *ps);
static inline size_t
psset_npageslabs(psset_t *psset) {
return psset->merged_stats.npageslabs;
}
static inline size_t
psset_nactive(psset_t *psset) {
return psset->merged_stats.nactive;
}
static inline size_t
psset_ndirty(psset_t *psset) {
return psset->merged_stats.ndirty;
}
#endif /* JEMALLOC_INTERNAL_PSSET_H */
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