diff options
Diffstat (limited to 'src/tcache.c')
| -rw-r--r-- | src/tcache.c | 171 |
1 files changed, 123 insertions, 48 deletions
diff --git a/src/tcache.c b/src/tcache.c index e2474a3..292c017 100644 --- a/src/tcache.c +++ b/src/tcache.c @@ -45,14 +45,16 @@ tcache_event_hard(tsd_t *tsd, tcache_t *tcache) { } else { tbin = tcache_large_bin_get(tcache, binind); } + bool repeat_bin; if (tbin->low_water > 0) { /* * Flush (ceiling) 3/4 of the objects below the low water mark. */ + unsigned nflushed; if (binind < NBINS) { - tcache_bin_flush_small(tsd, tcache, tbin, binind, - tbin->ncached - tbin->low_water + (tbin->low_water - >> 2)); + nflushed = tcache_bin_try_flush_small(tsd, tcache, tbin, + binind, tbin->ncached - tbin->low_water + + (tbin->low_water >> 2)); /* * Reduce fill count by 2X. Limit lg_fill_div such that * the fill count is always at least 1. @@ -63,23 +65,29 @@ tcache_event_hard(tsd_t *tsd, tcache_t *tcache) { tcache->lg_fill_div[binind]++; } } else { - tcache_bin_flush_large(tsd, tbin, binind, tbin->ncached - - tbin->low_water + (tbin->low_water >> 2), tcache); + nflushed = tcache_bin_try_flush_large(tsd, tcache, tbin, + binind, tbin->ncached - tbin->low_water + + (tbin->low_water >> 2)); } - } else if (tbin->low_water < 0) { - /* - * Increase fill count by 2X for small bins. Make sure - * lg_fill_div stays greater than 0. - */ - if (binind < NBINS && tcache->lg_fill_div[binind] > 1) { - tcache->lg_fill_div[binind]--; + repeat_bin = (nflushed == 0); + } else { + if (tbin->low_water < 0) { + /* + * Increase fill count by 2X for small bins. Make sure + * lg_fill_div stays greater than 0. + */ + if (binind < NBINS && tcache->lg_fill_div[binind] > 1) { + tcache->lg_fill_div[binind]--; + } } + repeat_bin = false; } - tbin->low_water = tbin->ncached; - - tcache->next_gc_bin++; - if (tcache->next_gc_bin == nhbins) { - tcache->next_gc_bin = 0; + if (!repeat_bin) { + tcache->next_gc_bin++; + if (tcache->next_gc_bin == nhbins) { + tcache->next_gc_bin = 0; + } + tbin->low_water = tbin->ncached; } } @@ -99,11 +107,9 @@ tcache_alloc_small_hard(tsdn_t *tsdn, arena_t *arena, tcache_t *tcache, return ret; } -void -tcache_bin_flush_small(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, - szind_t binind, unsigned rem) { - bool merged_stats = false; - +static unsigned +tcache_bin_flush_small_impl(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, + szind_t binind, unsigned rem, bool must_flush) { assert(binind < NBINS); assert(rem <= tbin->ncached); @@ -116,9 +122,12 @@ tcache_bin_flush_small(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, item_extent[i] = iealloc(tsd_tsdn(tsd), *(tbin->avail - 1 - i)); } + bool merged_stats = false; + unsigned nflushed = 0; + unsigned nskipped = 0; while (nflush > 0) { /* Lock the arena bin associated with the first object. */ - extent_t *extent = item_extent[0]; + extent_t *extent = item_extent[nskipped]; arena_t *bin_arena = extent_arena_get(extent); arena_bin_t *bin = &bin_arena->bins[binind]; @@ -130,7 +139,16 @@ tcache_bin_flush_small(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, tcache->prof_accumbytes = 0; } - malloc_mutex_lock(tsd_tsdn(tsd), &bin->lock); + if (must_flush) { + malloc_mutex_lock(tsd_tsdn(tsd), &bin->lock); + } else { + /* Make best effort to flush w/o blocking. */ + if (malloc_mutex_trylock(tsd_tsdn(tsd), &bin->lock)) { + nskipped++; + nflush--; + continue; + } + } if (config_stats && bin_arena == arena) { assert(!merged_stats); merged_stats = true; @@ -139,7 +157,7 @@ tcache_bin_flush_small(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, tbin->tstats.nrequests = 0; } unsigned ndeferred = 0; - for (unsigned i = 0; i < nflush; i++) { + for (unsigned i = nskipped; i < nflush; i++) { void *ptr = *(tbin->avail - 1 - i); extent = item_extent[i]; assert(ptr != NULL && extent != NULL); @@ -154,13 +172,14 @@ tcache_bin_flush_small(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, * locked. Stash the object, so that it can be * handled in a future pass. */ - *(tbin->avail - 1 - ndeferred) = ptr; - item_extent[ndeferred] = extent; + *(tbin->avail - 1 - ndeferred - nskipped) = ptr; + item_extent[ndeferred + nskipped] = extent; ndeferred++; } } malloc_mutex_unlock(tsd_tsdn(tsd), &bin->lock); arena_decay_ticks(tsd_tsdn(tsd), bin_arena, nflush - ndeferred); + nflushed += nflush - ndeferred; nflush = ndeferred; } if (config_stats && !merged_stats) { @@ -169,26 +188,49 @@ tcache_bin_flush_small(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, * arena, so the stats didn't get merged. Manually do so now. */ arena_bin_t *bin = &arena->bins[binind]; - malloc_mutex_lock(tsd_tsdn(tsd), &bin->lock); - bin->stats.nflushes++; - bin->stats.nrequests += tbin->tstats.nrequests; - tbin->tstats.nrequests = 0; - malloc_mutex_unlock(tsd_tsdn(tsd), &bin->lock); + if (must_flush) { + malloc_mutex_lock(tsd_tsdn(tsd), &bin->lock); + } + if (must_flush || + !malloc_mutex_trylock(tsd_tsdn(tsd), &bin->lock)) { + malloc_mutex_assert_owner(tsd_tsdn(tsd), &bin->lock); + bin->stats.nflushes++; + bin->stats.nrequests += tbin->tstats.nrequests; + tbin->tstats.nrequests = 0; + malloc_mutex_unlock(tsd_tsdn(tsd), &bin->lock); + } } + assert(nflushed == tbin->ncached - rem - nskipped); + assert(nskipped == 0 || !must_flush); - memmove(tbin->avail - rem, tbin->avail - tbin->ncached, rem * - sizeof(void *)); - tbin->ncached = rem; + if (nflushed > 0) { + memmove(tbin->avail - (rem + nskipped), tbin->avail - + tbin->ncached, rem * sizeof(void *)); + } + tbin->ncached = rem + nskipped; if ((low_water_t)tbin->ncached < tbin->low_water) { tbin->low_water = tbin->ncached; } + + return nflushed; } void -tcache_bin_flush_large(tsd_t *tsd, tcache_bin_t *tbin, szind_t binind, - unsigned rem, tcache_t *tcache) { - bool merged_stats = false; +tcache_bin_flush_small(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, + szind_t binind, unsigned rem) { + tcache_bin_flush_small_impl(tsd, tcache, tbin, binind, rem, true); +} + +unsigned +tcache_bin_try_flush_small(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, + szind_t binind, unsigned rem) { + return tcache_bin_flush_small_impl(tsd, tcache, tbin, binind, rem, + false); +} +static unsigned +tcache_bin_flush_large_impl(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, + szind_t binind, unsigned rem, bool must_flush) { assert(binind < nhbins); assert(rem <= tbin->ncached); @@ -201,18 +243,31 @@ tcache_bin_flush_large(tsd_t *tsd, tcache_bin_t *tbin, szind_t binind, item_extent[i] = iealloc(tsd_tsdn(tsd), *(tbin->avail - 1 - i)); } + bool merged_stats = false; + unsigned nflushed = 0; + unsigned nskipped = 0; while (nflush > 0) { /* Lock the arena associated with the first object. */ - extent_t *extent = item_extent[0]; + extent_t *extent = item_extent[nskipped]; arena_t *locked_arena = extent_arena_get(extent); UNUSED bool idump; if (config_prof) { idump = false; } + if (must_flush) { + malloc_mutex_lock(tsd_tsdn(tsd), &locked_arena->large_mtx); + } else { + /* Make best effort to flush w/o blocking. */ + if (malloc_mutex_trylock(tsd_tsdn(tsd), + &locked_arena->large_mtx)) { + nskipped++; + nflush--; + continue; + } + } - malloc_mutex_lock(tsd_tsdn(tsd), &locked_arena->large_mtx); - for (unsigned i = 0; i < nflush; i++) { + for (unsigned i = nskipped; i < nflush; i++) { void *ptr = *(tbin->avail - 1 - i); assert(ptr != NULL); extent = item_extent[i]; @@ -238,7 +293,7 @@ tcache_bin_flush_large(tsd_t *tsd, tcache_bin_t *tbin, szind_t binind, malloc_mutex_unlock(tsd_tsdn(tsd), &locked_arena->large_mtx); unsigned ndeferred = 0; - for (unsigned i = 0; i < nflush; i++) { + for (unsigned i = nskipped; i < nflush; i++) { void *ptr = *(tbin->avail - 1 - i); extent = item_extent[i]; assert(ptr != NULL && extent != NULL); @@ -252,8 +307,8 @@ tcache_bin_flush_large(tsd_t *tsd, tcache_bin_t *tbin, szind_t binind, * Stash the object, so that it can be handled * in a future pass. */ - *(tbin->avail - 1 - ndeferred) = ptr; - item_extent[ndeferred] = extent; + *(tbin->avail - 1 - ndeferred - nskipped) = ptr; + item_extent[ndeferred + nskipped] = extent; ndeferred++; } } @@ -262,6 +317,7 @@ tcache_bin_flush_large(tsd_t *tsd, tcache_bin_t *tbin, szind_t binind, } arena_decay_ticks(tsd_tsdn(tsd), locked_arena, nflush - ndeferred); + nflushed += nflush - ndeferred; nflush = ndeferred; } if (config_stats && !merged_stats) { @@ -274,12 +330,31 @@ tcache_bin_flush_large(tsd_t *tsd, tcache_bin_t *tbin, szind_t binind, tbin->tstats.nrequests = 0; } - memmove(tbin->avail - rem, tbin->avail - tbin->ncached, rem * - sizeof(void *)); - tbin->ncached = rem; + assert(nflushed == tbin->ncached - rem - nskipped); + assert(nskipped == 0 || !must_flush); + + if (nflushed > 0) { + memmove(tbin->avail - (rem + nskipped), tbin->avail - + tbin->ncached, rem * sizeof(void *)); + } + tbin->ncached = rem + nskipped; if ((low_water_t)tbin->ncached < tbin->low_water) { tbin->low_water = tbin->ncached; } + return nflushed; +} + +void +tcache_bin_flush_large(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, + szind_t binind, unsigned rem) { + tcache_bin_flush_large_impl(tsd, tcache, tbin, binind, rem, true); +} + +unsigned +tcache_bin_try_flush_large(tsd_t *tsd, tcache_t *tcache, tcache_bin_t *tbin, + szind_t binind, unsigned rem) { + return tcache_bin_flush_large_impl(tsd, tcache, tbin, binind, rem, + false); } void @@ -461,7 +536,7 @@ tcache_flush_cache(tsd_t *tsd, tcache_t *tcache) { } for (unsigned i = NBINS; i < nhbins; i++) { tcache_bin_t *tbin = tcache_large_bin_get(tcache, i); - tcache_bin_flush_large(tsd, tbin, i, 0, tcache); + tcache_bin_flush_large(tsd, tcache, tbin, i, 0); if (config_stats) { assert(tbin->tstats.nrequests == 0); |