mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-25 13:43:55 +08:00
c1935209df
Now that RCU no longer relies on failsafe checks, cpu_needs_another_gp() can be greatly simplified. This simplification eliminates the last call to rcu_future_needs_gp() and to rcu_segcblist_future_gp_needed(), both of which which can then be eliminated. And then, because cpu_needs_another_gp() is called only from __rcu_pending(), it can be inlined and eliminated. This commit carries out the simplification, inlining, and elimination called out above. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Nicholas Piggin <npiggin@gmail.com>
139 lines
4.7 KiB
C
139 lines
4.7 KiB
C
/*
|
|
* RCU segmented callback lists, internal-to-rcu header file
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, you can access it online at
|
|
* http://www.gnu.org/licenses/gpl-2.0.html.
|
|
*
|
|
* Copyright IBM Corporation, 2017
|
|
*
|
|
* Authors: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
|
|
*/
|
|
|
|
#include <linux/rcu_segcblist.h>
|
|
|
|
/*
|
|
* Account for the fact that a previously dequeued callback turned out
|
|
* to be marked as lazy.
|
|
*/
|
|
static inline void rcu_cblist_dequeued_lazy(struct rcu_cblist *rclp)
|
|
{
|
|
rclp->len_lazy--;
|
|
}
|
|
|
|
void rcu_cblist_init(struct rcu_cblist *rclp);
|
|
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 !rsclp->head;
|
|
}
|
|
|
|
/* Return number of callbacks in segmented callback list. */
|
|
static inline long rcu_segcblist_n_cbs(struct rcu_segcblist *rsclp)
|
|
{
|
|
return READ_ONCE(rsclp->len);
|
|
}
|
|
|
|
/* Return number of lazy callbacks in segmented callback list. */
|
|
static inline long rcu_segcblist_n_lazy_cbs(struct rcu_segcblist *rsclp)
|
|
{
|
|
return rsclp->len_lazy;
|
|
}
|
|
|
|
/* Return number of lazy callbacks in segmented callback list. */
|
|
static inline long rcu_segcblist_n_nonlazy_cbs(struct rcu_segcblist *rsclp)
|
|
{
|
|
return rsclp->len - rsclp->len_lazy;
|
|
}
|
|
|
|
/*
|
|
* Is the specified rcu_segcblist enabled, for example, not corresponding
|
|
* to an offline or callback-offloaded CPU?
|
|
*/
|
|
static inline bool rcu_segcblist_is_enabled(struct rcu_segcblist *rsclp)
|
|
{
|
|
return !!rsclp->tails[RCU_NEXT_TAIL];
|
|
}
|
|
|
|
/*
|
|
* 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 !*rsclp->tails[seg];
|
|
}
|
|
|
|
/*
|
|
* Interim function to return rcu_segcblist head pointer. Longer term, the
|
|
* rcu_segcblist will be used more pervasively, removing the need for this
|
|
* function.
|
|
*/
|
|
static inline struct rcu_head *rcu_segcblist_head(struct rcu_segcblist *rsclp)
|
|
{
|
|
return rsclp->head;
|
|
}
|
|
|
|
/*
|
|
* Interim function to return rcu_segcblist head pointer. Longer term, the
|
|
* rcu_segcblist will be used more pervasively, removing the need for this
|
|
* function.
|
|
*/
|
|
static inline struct rcu_head **rcu_segcblist_tail(struct rcu_segcblist *rsclp)
|
|
{
|
|
WARN_ON_ONCE(rcu_segcblist_empty(rsclp));
|
|
return rsclp->tails[RCU_NEXT_TAIL];
|
|
}
|
|
|
|
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);
|
|
void rcu_segcblist_enqueue(struct rcu_segcblist *rsclp,
|
|
struct rcu_head *rhp, bool lazy);
|
|
bool rcu_segcblist_entrain(struct rcu_segcblist *rsclp,
|
|
struct rcu_head *rhp, bool lazy);
|
|
void rcu_segcblist_extract_count(struct rcu_segcblist *rsclp,
|
|
struct rcu_cblist *rclp);
|
|
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);
|