| /* SPDX-License-Identifier: GPL-2.0+ */ |
| /* |
| * RCU segmented callback lists, internal-to-rcu header file |
| * |
| * Copyright IBM Corporation, 2017 |
| * |
| * Authors: Paul E. McKenney <paulmck@linux.ibm.com> |
| */ |
| |
| #include <linux/rcu_segcblist.h> |
| |
| /* Return number of callbacks in the specified callback list. */ |
| static inline long rcu_cblist_n_cbs(struct rcu_cblist *rclp) |
| { |
| return READ_ONCE(rclp->len); |
| } |
| |
| long rcu_segcblist_get_seglen(struct rcu_segcblist *rsclp, int seg); |
| |
| /* Return number of callbacks in segmented callback list by summing seglen. */ |
| long rcu_segcblist_n_segment_cbs(struct rcu_segcblist *rsclp); |
| |
| void rcu_cblist_init(struct rcu_cblist *rclp); |
| void rcu_cblist_enqueue(struct rcu_cblist *rclp, struct rcu_head *rhp); |
| void rcu_cblist_flush_enqueue(struct rcu_cblist *drclp, |
| struct rcu_cblist *srclp, |
| struct rcu_head *rhp); |
| struct rcu_head *rcu_cblist_dequeue(struct rcu_cblist *rclp); |
| |
| /* |
| * Is the specified rcu_segcblist structure empty? |
| * |
| * But careful! The fact that the ->head field is NULL does not |
| * necessarily imply that there are no callbacks associated with |
| * this structure. When callbacks are being invoked, they are |
| * removed as a group. If callback invocation must be preempted, |
| * the remaining callbacks will be added back to the list. Either |
| * way, the counts are updated later. |
| * |
| * So it is often the case that rcu_segcblist_n_cbs() should be used |
| * instead. |
| */ |
| static inline bool rcu_segcblist_empty(struct rcu_segcblist *rsclp) |
| { |
| return !READ_ONCE(rsclp->head); |
| } |
| |
| /* Return number of callbacks in segmented callback list. */ |
| static inline long rcu_segcblist_n_cbs(struct rcu_segcblist *rsclp) |
| { |
| #ifdef CONFIG_RCU_NOCB_CPU |
| return atomic_long_read(&rsclp->len); |
| #else |
| return READ_ONCE(rsclp->len); |
| #endif |
| } |
| |
| static inline void rcu_segcblist_set_flags(struct rcu_segcblist *rsclp, |
| int flags) |
| { |
| WRITE_ONCE(rsclp->flags, rsclp->flags | flags); |
| } |
| |
| static inline void rcu_segcblist_clear_flags(struct rcu_segcblist *rsclp, |
| int flags) |
| { |
| WRITE_ONCE(rsclp->flags, rsclp->flags & ~flags); |
| } |
| |
| static inline bool rcu_segcblist_test_flags(struct rcu_segcblist *rsclp, |
| int flags) |
| { |
| return READ_ONCE(rsclp->flags) & flags; |
| } |
| |
| /* |
| * Is the specified rcu_segcblist enabled, for example, not corresponding |
| * to an offline CPU? |
| */ |
| static inline bool rcu_segcblist_is_enabled(struct rcu_segcblist *rsclp) |
| { |
| return rcu_segcblist_test_flags(rsclp, SEGCBLIST_ENABLED); |
| } |
| |
| /* |
| * Is the specified rcu_segcblist NOCB offloaded (or in the middle of the |
| * [de]offloading process)? |
| */ |
| static inline bool rcu_segcblist_is_offloaded(struct rcu_segcblist *rsclp) |
| { |
| if (IS_ENABLED(CONFIG_RCU_NOCB_CPU) && |
| rcu_segcblist_test_flags(rsclp, SEGCBLIST_OFFLOADED)) |
| return true; |
| |
| return false; |
| } |
| |
| /* |
| * Are all segments following the specified segment of the specified |
| * rcu_segcblist structure empty of callbacks? (The specified |
| * segment might well contain callbacks.) |
| */ |
| static inline bool rcu_segcblist_restempty(struct rcu_segcblist *rsclp, int seg) |
| { |
| return !READ_ONCE(*READ_ONCE(rsclp->tails[seg])); |
| } |
| |
| /* |
| * Is the specified segment of the specified rcu_segcblist structure |
| * empty of callbacks? |
| */ |
| static inline bool rcu_segcblist_segempty(struct rcu_segcblist *rsclp, int seg) |
| { |
| if (seg == RCU_DONE_TAIL) |
| return &rsclp->head == rsclp->tails[RCU_DONE_TAIL]; |
| return rsclp->tails[seg - 1] == rsclp->tails[seg]; |
| } |
| |
| void rcu_segcblist_inc_len(struct rcu_segcblist *rsclp); |
| void rcu_segcblist_add_len(struct rcu_segcblist *rsclp, long v); |
| void rcu_segcblist_init(struct rcu_segcblist *rsclp); |
| void rcu_segcblist_disable(struct rcu_segcblist *rsclp); |
| bool rcu_segcblist_ready_cbs(struct rcu_segcblist *rsclp); |
| bool rcu_segcblist_pend_cbs(struct rcu_segcblist *rsclp); |
| struct rcu_head *rcu_segcblist_first_cb(struct rcu_segcblist *rsclp); |
| struct rcu_head *rcu_segcblist_first_pend_cb(struct rcu_segcblist *rsclp); |
| bool rcu_segcblist_nextgp(struct rcu_segcblist *rsclp, unsigned long *lp); |
| void rcu_segcblist_enqueue(struct rcu_segcblist *rsclp, |
| struct rcu_head *rhp); |
| bool rcu_segcblist_entrain(struct rcu_segcblist *rsclp, |
| struct rcu_head *rhp); |
| void rcu_segcblist_extract_done_cbs(struct rcu_segcblist *rsclp, |
| struct rcu_cblist *rclp); |
| void rcu_segcblist_extract_pend_cbs(struct rcu_segcblist *rsclp, |
| struct rcu_cblist *rclp); |
| void rcu_segcblist_insert_count(struct rcu_segcblist *rsclp, |
| struct rcu_cblist *rclp); |
| void rcu_segcblist_insert_done_cbs(struct rcu_segcblist *rsclp, |
| struct rcu_cblist *rclp); |
| void rcu_segcblist_insert_pend_cbs(struct rcu_segcblist *rsclp, |
| struct rcu_cblist *rclp); |
| void rcu_segcblist_advance(struct rcu_segcblist *rsclp, unsigned long seq); |
| bool rcu_segcblist_accelerate(struct rcu_segcblist *rsclp, unsigned long seq); |
| void rcu_segcblist_merge(struct rcu_segcblist *dst_rsclp, |
| struct rcu_segcblist *src_rsclp); |