Move hpdata bitmap logic out of the psset.

This commit is contained in:
David Goldblatt 2020-11-18 14:52:19 -08:00 committed by David Goldblatt
parent ca30b5db2b
commit 089f8fa442
3 changed files with 127 additions and 97 deletions

View File

@ -107,13 +107,15 @@ hpdata_longest_free_range_set(hpdata_t *hpdata, size_t longest_free_range) {
}
static inline void
hpdata_init(hpdata_t *hpdata, void *addr, uint64_t age) {
hpdata_addr_set(hpdata, addr);
hpdata_age_set(hpdata, age);
hpdata_huge_set(hpdata, false);
hpdata_nfree_set(hpdata, HUGEPAGE_PAGES);
hpdata_longest_free_range_set(hpdata, HUGEPAGE_PAGES);
fb_init(hpdata->active_pages, HUGEPAGE_PAGES);
hpdata_assert_empty(hpdata_t *hpdata) {
assert(fb_empty(hpdata->active_pages, HUGEPAGE_PAGES));
assert(hpdata_nfree_get(hpdata) == HUGEPAGE_PAGES);
}
static inline void
hpdata_assert_consistent(hpdata_t *hpdata) {
assert(fb_urange_longest(hpdata->active_pages, HUGEPAGE_PAGES)
== hpdata_longest_free_range_get(hpdata));
}
TYPED_LIST(hpdata_list, hpdata_t, ql_link)
@ -121,4 +123,12 @@ TYPED_LIST(hpdata_list, hpdata_t, ql_link)
typedef ph(hpdata_t) hpdata_age_heap_t;
ph_proto(, hpdata_age_heap_, hpdata_age_heap_t, hpdata_t);
void hpdata_init(hpdata_t *hpdata, void *addr, uint64_t age);
/*
* Given an hpdata which can serve an allocation request, pick and reserve an
* offset within that allocation.
*/
size_t hpdata_reserve_alloc(hpdata_t *hpdata, size_t npages);
void hpdata_unreserve(hpdata_t *hpdata, size_t start, size_t npages);
#endif /* JEMALLOC_INTERNAL_HPDATA_H */

View File

@ -16,3 +16,99 @@ hpdata_age_comp(const hpdata_t *a, const hpdata_t *b) {
}
ph_gen(, hpdata_age_heap_, hpdata_age_heap_t, hpdata_t, ph_link, hpdata_age_comp)
void
hpdata_init(hpdata_t *hpdata, void *addr, uint64_t age) {
hpdata_addr_set(hpdata, addr);
hpdata_age_set(hpdata, age);
hpdata_huge_set(hpdata, false);
hpdata_nfree_set(hpdata, HUGEPAGE_PAGES);
hpdata_longest_free_range_set(hpdata, HUGEPAGE_PAGES);
fb_init(hpdata->active_pages, HUGEPAGE_PAGES);
}
size_t
hpdata_reserve_alloc(hpdata_t *hpdata, size_t npages) {
assert(npages <= hpdata_longest_free_range_get(hpdata));
size_t result;
size_t start = 0;
/*
* These are dead stores, but the compiler will issue warnings on them
* since it can't tell statically that found is always true below.
*/
size_t begin = 0;
size_t len = 0;
size_t largest_unchosen_range = 0;
while (true) {
bool found = fb_urange_iter(hpdata->active_pages,
HUGEPAGE_PAGES, start, &begin, &len);
/*
* A precondition to this function is that hpdata must be able
* to serve the allocation.
*/
assert(found);
if (len >= npages) {
/*
* We use first-fit within the page slabs; this gives
* bounded worst-case fragmentation within a slab. It's
* not necessarily right; we could experiment with
* various other options.
*/
break;
}
if (len > largest_unchosen_range) {
largest_unchosen_range = len;
}
start = begin + len;
}
/* We found a range; remember it. */
result = begin;
fb_set_range(hpdata->active_pages, HUGEPAGE_PAGES, begin, npages);
hpdata_nfree_set(hpdata, hpdata_nfree_get(hpdata) - npages);
/*
* We might have shrunk the longest free range. We have to keep
* scanning until the end of the hpdata to be sure.
*
* TODO: As an optimization, we should only do this when the range we
* just allocated from was equal to the longest free range size.
*/
start = begin + npages;
while (start < HUGEPAGE_PAGES) {
bool found = fb_urange_iter(hpdata->active_pages,
HUGEPAGE_PAGES, start, &begin, &len);
if (!found) {
break;
}
if (len > largest_unchosen_range) {
largest_unchosen_range = len;
}
start = begin + len;
}
hpdata_longest_free_range_set(hpdata, largest_unchosen_range);
return result;
}
void
hpdata_unreserve(hpdata_t *hpdata, size_t begin, size_t npages) {
size_t old_longest_range = hpdata_longest_free_range_get(hpdata);
fb_unset_range(hpdata->active_pages, HUGEPAGE_PAGES, begin, npages);
/* We might have just created a new, larger range. */
size_t new_begin = (fb_fls(hpdata->active_pages, HUGEPAGE_PAGES,
begin) + 1);
size_t new_end = fb_ffs(hpdata->active_pages, HUGEPAGE_PAGES,
begin + npages - 1);
size_t new_range_len = new_end - new_begin;
if (new_range_len > old_longest_range) {
hpdata_longest_free_range_set(hpdata, new_range_len);
}
hpdata_nfree_set(hpdata, hpdata_nfree_get(hpdata) + npages);
}

View File

@ -105,15 +105,9 @@ psset_hpdata_heap_insert(psset_t *psset, pszind_t pind, hpdata_t *ps) {
psset_bin_stats_insert(&psset->stats.nonfull_slabs[pind], ps);
}
JEMALLOC_ALWAYS_INLINE void
psset_assert_ps_consistent(hpdata_t *ps) {
assert(fb_urange_longest(ps->active_pages, HUGEPAGE_PAGES)
== hpdata_longest_free_range_get(ps));
}
void
psset_insert(psset_t *psset, hpdata_t *ps) {
psset_assert_ps_consistent(ps);
hpdata_assert_consistent(ps);
size_t longest_free_range = hpdata_longest_free_range_get(ps);
if (longest_free_range == 0) {
@ -137,7 +131,7 @@ psset_insert(psset_t *psset, hpdata_t *ps) {
void
psset_remove(psset_t *psset, hpdata_t *ps) {
psset_assert_ps_consistent(ps);
hpdata_assert_consistent(ps);
size_t longest_free_range = hpdata_longest_free_range_get(ps);
if (longest_free_range == 0) {
@ -157,7 +151,7 @@ psset_remove(psset_t *psset, hpdata_t *ps) {
void
psset_hugify(psset_t *psset, hpdata_t *ps) {
assert(!hpdata_huge_get(ps));
psset_assert_ps_consistent(ps);
hpdata_assert_consistent(ps);
size_t longest_free_range = hpdata_longest_free_range_get(ps);
psset_bin_stats_t *bin_stats;
@ -196,7 +190,7 @@ psset_recycle_extract(psset_t *psset, size_t size) {
bitmap_set(psset->bitmap, &psset_bitmap_info, pind);
}
psset_assert_ps_consistent(ps);
hpdata_assert_consistent(ps);
return ps;
}
@ -207,76 +201,18 @@ psset_recycle_extract(psset_t *psset, size_t size) {
static void
psset_ps_alloc_insert(psset_t *psset, hpdata_t *ps, edata_t *r_edata,
size_t size) {
size_t start = 0;
/*
* These are dead stores, but the compiler will issue warnings on them
* since it can't tell statically that found is always true below.
*/
size_t begin = 0;
size_t len = 0;
fb_group_t *ps_fb = ps->active_pages;
size_t npages = size >> LG_PAGE;
size_t largest_unchosen_range = 0;
while (true) {
bool found = fb_urange_iter(ps_fb, HUGEPAGE_PAGES, start,
&begin, &len);
/*
* A precondition to this function is that ps must be able to
* serve the allocation.
*/
assert(found);
if (len >= npages) {
/*
* We use first-fit within the page slabs; this gives
* bounded worst-case fragmentation within a slab. It's
* not necessarily right; we could experiment with
* various other options.
*/
break;
}
if (len > largest_unchosen_range) {
largest_unchosen_range = len;
}
start = begin + len;
}
size_t npages = size / PAGE;
size_t begin = hpdata_reserve_alloc(ps, npages);
uintptr_t addr = (uintptr_t)hpdata_addr_get(ps) + begin * PAGE;
edata_init(r_edata, edata_arena_ind_get(r_edata), (void *)addr, size,
/* slab */ false, SC_NSIZES, /* sn */ 0, extent_state_active,
/* zeroed */ false, /* committed */ true, EXTENT_PAI_HPA,
EXTENT_NOT_HEAD);
edata_ps_set(r_edata, ps);
fb_set_range(ps_fb, HUGEPAGE_PAGES, begin, npages);
hpdata_nfree_set(ps, (uint32_t)(hpdata_nfree_get(ps) - npages));
/* The pageslab isn't in a bin, so no bin stats need to change. */
/*
* OK, we've got to put the pageslab back. First we have to figure out
* where, though; we've only checked run sizes before the pageslab we
* picked. We also need to look for ones after the one we picked. Note
* that we want begin + npages as the start position, not begin + len;
* we might not have used the whole range.
*
* TODO: With a little bit more care, we can guarantee that the longest
* free range field in the edata is accurate upon entry, and avoid doing
* this check in the case where we're allocating from some smaller run.
*/
start = begin + npages;
while (start < HUGEPAGE_PAGES) {
bool found = fb_urange_iter(ps_fb, HUGEPAGE_PAGES, start, &begin,
&len);
if (!found) {
break;
}
if (len > largest_unchosen_range) {
largest_unchosen_range = len;
}
start = begin + len;
}
hpdata_longest_free_range_set(ps, (uint32_t)largest_unchosen_range);
if (largest_unchosen_range == 0) {
size_t longest_free_range = hpdata_longest_free_range_get(ps);
if (longest_free_range == 0) {
psset_bin_stats_insert(&psset->stats.full_slabs, ps);
} else {
psset_insert(psset, ps);
@ -295,9 +231,7 @@ psset_alloc_reuse(psset_t *psset, edata_t *r_edata, size_t size) {
void
psset_alloc_new(psset_t *psset, hpdata_t *ps, edata_t *r_edata, size_t size) {
fb_group_t *ps_fb = ps->active_pages;
assert(fb_empty(ps_fb, HUGEPAGE_PAGES));
assert(hpdata_nfree_get(ps) == HUGEPAGE_PAGES);
hpdata_assert_empty(ps);
psset_ps_alloc_insert(psset, ps, r_edata, size);
}
@ -307,7 +241,6 @@ psset_dalloc(psset_t *psset, edata_t *edata) {
assert(edata_ps_get(edata) != NULL);
hpdata_t *ps = edata_ps_get(edata);
fb_group_t *ps_fb = ps->active_pages;
size_t ps_old_longest_free_range = hpdata_longest_free_range_get(ps);
pszind_t old_pind = SC_NPSIZES;
if (ps_old_longest_free_range != 0) {
@ -319,32 +252,23 @@ psset_dalloc(psset_t *psset, edata_t *edata) {
((uintptr_t)edata_base_get(edata) - (uintptr_t)hpdata_addr_get(ps))
>> LG_PAGE;
size_t len = edata_size_get(edata) >> LG_PAGE;
fb_unset_range(ps_fb, HUGEPAGE_PAGES, begin, len);
/* The pageslab is still in the bin; adjust its stats first. */
psset_bin_stats_t *bin_stats = (ps_old_longest_free_range == 0
? &psset->stats.full_slabs : &psset->stats.nonfull_slabs[old_pind]);
psset_bin_stats_deactivate(bin_stats, hpdata_huge_get(ps), len);
hpdata_nfree_set(ps, (uint32_t)(hpdata_nfree_get(ps) + len));
hpdata_unreserve(ps, begin, len);
size_t ps_new_longest_free_range = hpdata_longest_free_range_get(ps);
/* We might have just created a new, larger range. */
size_t new_begin = (size_t)(fb_fls(ps_fb, HUGEPAGE_PAGES, begin) + 1);
size_t new_end = fb_ffs(ps_fb, HUGEPAGE_PAGES, begin + len - 1);
size_t new_range_len = new_end - new_begin;
/*
* If the new free range is no longer than the previous longest one,
* then the pageslab is non-empty and doesn't need to change bins.
* We're done, and don't need to return a pageslab to evict.
*/
if (new_range_len <= ps_old_longest_free_range) {
if (ps_new_longest_free_range <= ps_old_longest_free_range) {
return NULL;
}
/*
* Otherwise, it might need to get evicted from the set, or change its
* bin.
*/
hpdata_longest_free_range_set(ps, (uint32_t)new_range_len);
/*
* If it was previously non-full, then it's in some (possibly now
* incorrect) bin already; remove it.
@ -371,12 +295,12 @@ psset_dalloc(psset_t *psset, edata_t *edata) {
psset_bin_stats_remove(&psset->stats.full_slabs, ps);
}
/* If the pageslab is empty, it gets evicted from the set. */
if (new_range_len == HUGEPAGE_PAGES) {
if (ps_new_longest_free_range == HUGEPAGE_PAGES) {
return ps;
}
/* Otherwise, it gets reinserted. */
pszind_t new_pind = sz_psz2ind(sz_psz_quantize_floor(
new_range_len << LG_PAGE));
ps_new_longest_free_range << LG_PAGE));
if (hpdata_age_heap_empty(&psset->pageslabs[new_pind])) {
bitmap_unset(psset->bitmap, &psset_bitmap_info,
(size_t)new_pind);