From d079b656b4719739b2247dcd9d46e9bec793095a Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 Feb 2023 17:11:34 +0100 Subject: Merging upstream version 1.38.0. Signed-off-by: Daniel Baumann --- database/engine/rrdenglocking.c | 241 ---------------------------------------- 1 file changed, 241 deletions(-) delete mode 100644 database/engine/rrdenglocking.c (limited to 'database/engine/rrdenglocking.c') diff --git a/database/engine/rrdenglocking.c b/database/engine/rrdenglocking.c deleted file mode 100644 index a23abf307..000000000 --- a/database/engine/rrdenglocking.c +++ /dev/null @@ -1,241 +0,0 @@ -// SPDX-License-Identifier: GPL-3.0-or-later -#include "rrdengine.h" - -struct page_cache_descr *rrdeng_create_pg_cache_descr(struct rrdengine_instance *ctx) -{ - struct page_cache_descr *pg_cache_descr; - - pg_cache_descr = mallocz(sizeof(*pg_cache_descr)); - rrd_stat_atomic_add(&ctx->stats.page_cache_descriptors, 1); - pg_cache_descr->page = NULL; - pg_cache_descr->flags = 0; - pg_cache_descr->prev = pg_cache_descr->next = NULL; - pg_cache_descr->refcnt = 0; - pg_cache_descr->waiters = 0; - fatal_assert(0 == uv_cond_init(&pg_cache_descr->cond)); - fatal_assert(0 == uv_mutex_init(&pg_cache_descr->mutex)); - - return pg_cache_descr; -} - -void rrdeng_destroy_pg_cache_descr(struct rrdengine_instance *ctx, struct page_cache_descr *pg_cache_descr) -{ - uv_cond_destroy(&pg_cache_descr->cond); - uv_mutex_destroy(&pg_cache_descr->mutex); - freez(pg_cache_descr); - rrd_stat_atomic_add(&ctx->stats.page_cache_descriptors, -1); -} - -/* also allocates page cache descriptor if missing */ -void rrdeng_page_descr_mutex_lock(struct rrdengine_instance *ctx, struct rrdeng_page_descr *descr) -{ - unsigned long old_state, old_users, new_state, ret_state; - struct page_cache_descr *pg_cache_descr = NULL; - uint8_t we_locked; - - we_locked = 0; - while (1) { /* spin */ - old_state = descr->pg_cache_descr_state; - old_users = old_state >> PG_CACHE_DESCR_SHIFT; - - if (unlikely(we_locked)) { - fatal_assert(old_state & PG_CACHE_DESCR_LOCKED); - new_state = (1 << PG_CACHE_DESCR_SHIFT) | PG_CACHE_DESCR_ALLOCATED; - ret_state = ulong_compare_and_swap(&descr->pg_cache_descr_state, old_state, new_state); - if (old_state == ret_state) { - /* success */ - break; - } - continue; /* spin */ - } - if (old_state & PG_CACHE_DESCR_LOCKED) { - fatal_assert(0 == old_users); - continue; /* spin */ - } - if (0 == old_state) { - /* no page cache descriptor has been allocated */ - - if (NULL == pg_cache_descr) { - pg_cache_descr = rrdeng_create_pg_cache_descr(ctx); - } - new_state = PG_CACHE_DESCR_LOCKED; - ret_state = ulong_compare_and_swap(&descr->pg_cache_descr_state, 0, new_state); - if (0 == ret_state) { - we_locked = 1; - descr->pg_cache_descr = pg_cache_descr; - pg_cache_descr->descr = descr; - pg_cache_descr = NULL; /* make sure we don't free pg_cache_descr */ - /* retry */ - continue; - } - continue; /* spin */ - } - /* page cache descriptor is already allocated */ - if (unlikely(!(old_state & PG_CACHE_DESCR_ALLOCATED))) { - fatal("Invalid page cache descriptor locking state:%#lX", old_state); - } - new_state = (old_users + 1) << PG_CACHE_DESCR_SHIFT; - new_state |= old_state & PG_CACHE_DESCR_FLAGS_MASK; - - ret_state = ulong_compare_and_swap(&descr->pg_cache_descr_state, old_state, new_state); - if (old_state == ret_state) { - /* success */ - break; - } - /* spin */ - } - - if (pg_cache_descr) { - rrdeng_destroy_pg_cache_descr(ctx, pg_cache_descr); - } - pg_cache_descr = descr->pg_cache_descr; - uv_mutex_lock(&pg_cache_descr->mutex); -} - -void rrdeng_page_descr_mutex_unlock(struct rrdengine_instance *ctx, struct rrdeng_page_descr *descr) -{ - unsigned long old_state, new_state, ret_state, old_users; - struct page_cache_descr *pg_cache_descr, *delete_pg_cache_descr = NULL; - uint8_t we_locked; - - uv_mutex_unlock(&descr->pg_cache_descr->mutex); - - we_locked = 0; - while (1) { /* spin */ - old_state = descr->pg_cache_descr_state; - old_users = old_state >> PG_CACHE_DESCR_SHIFT; - - if (unlikely(we_locked)) { - fatal_assert(0 == old_users); - - ret_state = ulong_compare_and_swap(&descr->pg_cache_descr_state, old_state, 0); - if (old_state == ret_state) { - /* success */ - rrdeng_destroy_pg_cache_descr(ctx, delete_pg_cache_descr); - return; - } - continue; /* spin */ - } - if (old_state & PG_CACHE_DESCR_LOCKED) { - fatal_assert(0 == old_users); - continue; /* spin */ - } - fatal_assert(old_state & PG_CACHE_DESCR_ALLOCATED); - pg_cache_descr = descr->pg_cache_descr; - /* caller is the only page cache descriptor user and there are no pending references on the page */ - if ((old_state & PG_CACHE_DESCR_DESTROY) && (1 == old_users) && - !pg_cache_descr->flags && !pg_cache_descr->refcnt) { - fatal_assert(!pg_cache_descr->waiters); - - new_state = PG_CACHE_DESCR_LOCKED; - ret_state = ulong_compare_and_swap(&descr->pg_cache_descr_state, old_state, new_state); - if (old_state == ret_state) { - we_locked = 1; - delete_pg_cache_descr = pg_cache_descr; - descr->pg_cache_descr = NULL; - /* retry */ - continue; - } - continue; /* spin */ - } - fatal_assert(old_users > 0); - new_state = (old_users - 1) << PG_CACHE_DESCR_SHIFT; - new_state |= old_state & PG_CACHE_DESCR_FLAGS_MASK; - - ret_state = ulong_compare_and_swap(&descr->pg_cache_descr_state, old_state, new_state); - if (old_state == ret_state) { - /* success */ - break; - } - /* spin */ - } -} - -/* - * Tries to deallocate page cache descriptor. If it fails, it postpones deallocation by setting the - * PG_CACHE_DESCR_DESTROY flag which will be eventually cleared by a different context after doing - * the deallocation. - */ -void rrdeng_try_deallocate_pg_cache_descr(struct rrdengine_instance *ctx, struct rrdeng_page_descr *descr) -{ - unsigned long old_state, new_state, ret_state, old_users; - struct page_cache_descr *pg_cache_descr = NULL; - uint8_t just_locked, can_free, must_unlock; - - just_locked = 0; - can_free = 0; - must_unlock = 0; - while (1) { /* spin */ - old_state = descr->pg_cache_descr_state; - old_users = old_state >> PG_CACHE_DESCR_SHIFT; - - if (unlikely(just_locked)) { - fatal_assert(0 == old_users); - - must_unlock = 1; - just_locked = 0; - /* Try deallocate if there are no pending references on the page */ - if (!pg_cache_descr->flags && !pg_cache_descr->refcnt) { - fatal_assert(!pg_cache_descr->waiters); - - descr->pg_cache_descr = NULL; - can_free = 1; - /* success */ - continue; - } - continue; /* spin */ - } - if (unlikely(must_unlock)) { - fatal_assert(0 == old_users); - - if (can_free) { - /* success */ - new_state = 0; - } else { - new_state = old_state | PG_CACHE_DESCR_DESTROY; - new_state &= ~PG_CACHE_DESCR_LOCKED; - } - ret_state = ulong_compare_and_swap(&descr->pg_cache_descr_state, old_state, new_state); - if (old_state == ret_state) { - /* unlocked */ - if (can_free) - rrdeng_destroy_pg_cache_descr(ctx, pg_cache_descr); - return; - } - continue; /* spin */ - } - if (!(old_state & PG_CACHE_DESCR_ALLOCATED)) { - /* don't do anything */ - return; - } - if (old_state & PG_CACHE_DESCR_LOCKED) { - fatal_assert(0 == old_users); - continue; /* spin */ - } - /* caller is the only page cache descriptor user */ - if (0 == old_users) { - new_state = old_state | PG_CACHE_DESCR_LOCKED; - ret_state = ulong_compare_and_swap(&descr->pg_cache_descr_state, old_state, new_state); - if (old_state == ret_state) { - just_locked = 1; - pg_cache_descr = descr->pg_cache_descr; - /* retry */ - continue; - } - continue; /* spin */ - } - if (old_state & PG_CACHE_DESCR_DESTROY) { - /* don't do anything */ - return; - } - /* plant PG_CACHE_DESCR_DESTROY so that other contexts eventually free the page cache descriptor */ - new_state = old_state | PG_CACHE_DESCR_DESTROY; - - ret_state = ulong_compare_and_swap(&descr->pg_cache_descr_state, old_state, new_state); - if (old_state == ret_state) { - /* success */ - return; - } - /* spin */ - } -} \ No newline at end of file -- cgit v1.2.3