summaryrefslogtreecommitdiffstats
path: root/deps/jemalloc/src/hpdata.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 13:40:54 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 13:40:54 +0000
commit317c0644ccf108aa23ef3fd8358bd66c2840bfc0 (patch)
treec417b3d25c86b775989cb5ac042f37611b626c8a /deps/jemalloc/src/hpdata.c
parentInitial commit. (diff)
downloadredis-317c0644ccf108aa23ef3fd8358bd66c2840bfc0.tar.xz
redis-317c0644ccf108aa23ef3fd8358bd66c2840bfc0.zip
Adding upstream version 5:7.2.4.upstream/5%7.2.4
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'deps/jemalloc/src/hpdata.c')
-rw-r--r--deps/jemalloc/src/hpdata.c325
1 files changed, 325 insertions, 0 deletions
diff --git a/deps/jemalloc/src/hpdata.c b/deps/jemalloc/src/hpdata.c
new file mode 100644
index 0000000..e7d7294
--- /dev/null
+++ b/deps/jemalloc/src/hpdata.c
@@ -0,0 +1,325 @@
+#include "jemalloc/internal/jemalloc_preamble.h"
+#include "jemalloc/internal/jemalloc_internal_includes.h"
+
+#include "jemalloc/internal/hpdata.h"
+
+static int
+hpdata_age_comp(const hpdata_t *a, const hpdata_t *b) {
+ uint64_t a_age = hpdata_age_get(a);
+ uint64_t b_age = hpdata_age_get(b);
+ /*
+ * hpdata ages are operation counts in the psset; no two should be the
+ * same.
+ */
+ assert(a_age != b_age);
+ return (a_age > b_age) - (a_age < b_age);
+}
+
+ph_gen(, hpdata_age_heap, hpdata_t, age_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->h_huge = false;
+ hpdata->h_alloc_allowed = true;
+ hpdata->h_in_psset_alloc_container = false;
+ hpdata->h_purge_allowed = false;
+ hpdata->h_hugify_allowed = false;
+ hpdata->h_in_psset_hugify_container = false;
+ hpdata->h_mid_purge = false;
+ hpdata->h_mid_hugify = false;
+ hpdata->h_updating = false;
+ hpdata->h_in_psset = false;
+ hpdata_longest_free_range_set(hpdata, HUGEPAGE_PAGES);
+ hpdata->h_nactive = 0;
+ fb_init(hpdata->active_pages, HUGEPAGE_PAGES);
+ hpdata->h_ntouched = 0;
+ fb_init(hpdata->touched_pages, HUGEPAGE_PAGES);
+
+ hpdata_assert_consistent(hpdata);
+}
+
+void *
+hpdata_reserve_alloc(hpdata_t *hpdata, size_t sz) {
+ hpdata_assert_consistent(hpdata);
+ /*
+ * This is a metadata change; the hpdata should therefore either not be
+ * in the psset, or should have explicitly marked itself as being
+ * mid-update.
+ */
+ assert(!hpdata->h_in_psset || hpdata->h_updating);
+ assert(hpdata->h_alloc_allowed);
+ assert((sz & PAGE_MASK) == 0);
+ size_t npages = sz >> LG_PAGE;
+ 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);
+ assert(len <= hpdata_longest_free_range_get(hpdata));
+ 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->h_nactive += npages;
+
+ /*
+ * We might be about to dirty some memory for the first time; update our
+ * count if so.
+ */
+ size_t new_dirty = fb_ucount(hpdata->touched_pages, HUGEPAGE_PAGES,
+ result, npages);
+ fb_set_range(hpdata->touched_pages, HUGEPAGE_PAGES, result, npages);
+ hpdata->h_ntouched += new_dirty;
+
+ /*
+ * If we allocated out of a range that was the longest in the hpdata, it
+ * might be the only one of that size and we'll have to adjust the
+ * metadata.
+ */
+ if (len == hpdata_longest_free_range_get(hpdata)) {
+ start = begin + npages;
+ while (start < HUGEPAGE_PAGES) {
+ bool found = fb_urange_iter(hpdata->active_pages,
+ HUGEPAGE_PAGES, start, &begin, &len);
+ if (!found) {
+ break;
+ }
+ assert(len <= hpdata_longest_free_range_get(hpdata));
+ if (len == hpdata_longest_free_range_get(hpdata)) {
+ largest_unchosen_range = len;
+ break;
+ }
+ if (len > largest_unchosen_range) {
+ largest_unchosen_range = len;
+ }
+ start = begin + len;
+ }
+ hpdata_longest_free_range_set(hpdata, largest_unchosen_range);
+ }
+
+ hpdata_assert_consistent(hpdata);
+ return (void *)(
+ (uintptr_t)hpdata_addr_get(hpdata) + (result << LG_PAGE));
+}
+
+void
+hpdata_unreserve(hpdata_t *hpdata, void *addr, size_t sz) {
+ hpdata_assert_consistent(hpdata);
+ /* See the comment in reserve. */
+ assert(!hpdata->h_in_psset || hpdata->h_updating);
+ assert(((uintptr_t)addr & PAGE_MASK) == 0);
+ assert((sz & PAGE_MASK) == 0);
+ size_t begin = ((uintptr_t)addr - (uintptr_t)hpdata_addr_get(hpdata))
+ >> LG_PAGE;
+ assert(begin < HUGEPAGE_PAGES);
+ size_t npages = sz >> LG_PAGE;
+ 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->h_nactive -= npages;
+
+ hpdata_assert_consistent(hpdata);
+}
+
+size_t
+hpdata_purge_begin(hpdata_t *hpdata, hpdata_purge_state_t *purge_state) {
+ hpdata_assert_consistent(hpdata);
+ /*
+ * See the comment below; we might purge any inactive extent, so it's
+ * unsafe for any other thread to turn any inactive extent active while
+ * we're operating on it.
+ */
+ assert(!hpdata_alloc_allowed_get(hpdata));
+
+ purge_state->npurged = 0;
+ purge_state->next_purge_search_begin = 0;
+
+ /*
+ * Initialize to_purge.
+ *
+ * It's possible to end up in situations where two dirty extents are
+ * separated by a retained extent:
+ * - 1 page allocated.
+ * - 1 page allocated.
+ * - 1 pages allocated.
+ *
+ * If the middle page is freed and purged, and then the first and third
+ * pages are freed, and then another purge pass happens, the hpdata
+ * looks like this:
+ * - 1 page dirty.
+ * - 1 page retained.
+ * - 1 page dirty.
+ *
+ * But it's safe to do a single 3-page purge.
+ *
+ * We do this by first computing the dirty pages, and then filling in
+ * any gaps by extending each range in the dirty bitmap to extend until
+ * the next active page. This purges more pages, but the expensive part
+ * of purging is the TLB shootdowns, rather than the kernel state
+ * tracking; doing a little bit more of the latter is fine if it saves
+ * us from doing some of the former.
+ */
+
+ /*
+ * The dirty pages are those that are touched but not active. Note that
+ * in a normal-ish case, HUGEPAGE_PAGES is something like 512 and the
+ * fb_group_t is 64 bits, so this is 64 bytes, spread across 8
+ * fb_group_ts.
+ */
+ fb_group_t dirty_pages[FB_NGROUPS(HUGEPAGE_PAGES)];
+ fb_init(dirty_pages, HUGEPAGE_PAGES);
+ fb_bit_not(dirty_pages, hpdata->active_pages, HUGEPAGE_PAGES);
+ fb_bit_and(dirty_pages, dirty_pages, hpdata->touched_pages,
+ HUGEPAGE_PAGES);
+
+ fb_init(purge_state->to_purge, HUGEPAGE_PAGES);
+ size_t next_bit = 0;
+ while (next_bit < HUGEPAGE_PAGES) {
+ size_t next_dirty = fb_ffs(dirty_pages, HUGEPAGE_PAGES,
+ next_bit);
+ /* Recall that fb_ffs returns nbits if no set bit is found. */
+ if (next_dirty == HUGEPAGE_PAGES) {
+ break;
+ }
+ size_t next_active = fb_ffs(hpdata->active_pages,
+ HUGEPAGE_PAGES, next_dirty);
+ /*
+ * Don't purge past the end of the dirty extent, into retained
+ * pages. This helps the kernel a tiny bit, but honestly it's
+ * mostly helpful for testing (where we tend to write test cases
+ * that think in terms of the dirty ranges).
+ */
+ ssize_t last_dirty = fb_fls(dirty_pages, HUGEPAGE_PAGES,
+ next_active - 1);
+ assert(last_dirty >= 0);
+ assert((size_t)last_dirty >= next_dirty);
+ assert((size_t)last_dirty - next_dirty + 1 <= HUGEPAGE_PAGES);
+
+ fb_set_range(purge_state->to_purge, HUGEPAGE_PAGES, next_dirty,
+ last_dirty - next_dirty + 1);
+ next_bit = next_active + 1;
+ }
+
+ /* We should purge, at least, everything dirty. */
+ size_t ndirty = hpdata->h_ntouched - hpdata->h_nactive;
+ purge_state->ndirty_to_purge = ndirty;
+ assert(ndirty <= fb_scount(
+ purge_state->to_purge, HUGEPAGE_PAGES, 0, HUGEPAGE_PAGES));
+ assert(ndirty == fb_scount(dirty_pages, HUGEPAGE_PAGES, 0,
+ HUGEPAGE_PAGES));
+
+ hpdata_assert_consistent(hpdata);
+
+ return ndirty;
+}
+
+bool
+hpdata_purge_next(hpdata_t *hpdata, hpdata_purge_state_t *purge_state,
+ void **r_purge_addr, size_t *r_purge_size) {
+ /*
+ * Note that we don't have a consistency check here; we're accessing
+ * hpdata without synchronization, and therefore have no right to expect
+ * a consistent state.
+ */
+ assert(!hpdata_alloc_allowed_get(hpdata));
+
+ if (purge_state->next_purge_search_begin == HUGEPAGE_PAGES) {
+ return false;
+ }
+ size_t purge_begin;
+ size_t purge_len;
+ bool found_range = fb_srange_iter(purge_state->to_purge, HUGEPAGE_PAGES,
+ purge_state->next_purge_search_begin, &purge_begin, &purge_len);
+ if (!found_range) {
+ return false;
+ }
+
+ *r_purge_addr = (void *)(
+ (uintptr_t)hpdata_addr_get(hpdata) + purge_begin * PAGE);
+ *r_purge_size = purge_len * PAGE;
+
+ purge_state->next_purge_search_begin = purge_begin + purge_len;
+ purge_state->npurged += purge_len;
+ assert(purge_state->npurged <= HUGEPAGE_PAGES);
+
+ return true;
+}
+
+void
+hpdata_purge_end(hpdata_t *hpdata, hpdata_purge_state_t *purge_state) {
+ assert(!hpdata_alloc_allowed_get(hpdata));
+ hpdata_assert_consistent(hpdata);
+ /* See the comment in reserve. */
+ assert(!hpdata->h_in_psset || hpdata->h_updating);
+
+ assert(purge_state->npurged == fb_scount(purge_state->to_purge,
+ HUGEPAGE_PAGES, 0, HUGEPAGE_PAGES));
+ assert(purge_state->npurged >= purge_state->ndirty_to_purge);
+
+ fb_bit_not(purge_state->to_purge, purge_state->to_purge,
+ HUGEPAGE_PAGES);
+ fb_bit_and(hpdata->touched_pages, hpdata->touched_pages,
+ purge_state->to_purge, HUGEPAGE_PAGES);
+ assert(hpdata->h_ntouched >= purge_state->ndirty_to_purge);
+ hpdata->h_ntouched -= purge_state->ndirty_to_purge;
+
+ hpdata_assert_consistent(hpdata);
+}
+
+void
+hpdata_hugify(hpdata_t *hpdata) {
+ hpdata_assert_consistent(hpdata);
+ hpdata->h_huge = true;
+ fb_set_range(hpdata->touched_pages, HUGEPAGE_PAGES, 0, HUGEPAGE_PAGES);
+ hpdata->h_ntouched = HUGEPAGE_PAGES;
+ hpdata_assert_consistent(hpdata);
+}
+
+void
+hpdata_dehugify(hpdata_t *hpdata) {
+ hpdata_assert_consistent(hpdata);
+ hpdata->h_huge = false;
+ hpdata_assert_consistent(hpdata);
+}