From aacb5d91ab1bfbb0e8123da59a2e333d52ba7f60 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Sun, 28 Oct 2018 10:32:51 -0700 Subject: srcu: Use "ssp" instead of "sp" for srcu_struct pointer In RCU, the distinction between "rsp", "rnp", and "rdp" has served well for a great many years, but in SRCU, "sp" vs. "sdp" has proven confusing. This commit therefore renames SRCU's "sp" pointers to "ssp", so that there is "ssp" for srcu_struct pointer, "snp" for srcu_node pointer, and "sdp" for srcu_data pointer. Signed-off-by: Paul E. McKenney --- kernel/rcu/srcutiny.c | 120 +++++++++++++++++++++++++------------------------- 1 file changed, 60 insertions(+), 60 deletions(-) (limited to 'kernel/rcu/srcutiny.c') diff --git a/kernel/rcu/srcutiny.c b/kernel/rcu/srcutiny.c index b46e6683f8c9..32dfd6522548 100644 --- a/kernel/rcu/srcutiny.c +++ b/kernel/rcu/srcutiny.c @@ -37,30 +37,30 @@ int rcu_scheduler_active __read_mostly; static LIST_HEAD(srcu_boot_list); static bool srcu_init_done; -static int init_srcu_struct_fields(struct srcu_struct *sp) +static int init_srcu_struct_fields(struct srcu_struct *ssp) { - sp->srcu_lock_nesting[0] = 0; - sp->srcu_lock_nesting[1] = 0; - init_swait_queue_head(&sp->srcu_wq); - sp->srcu_cb_head = NULL; - sp->srcu_cb_tail = &sp->srcu_cb_head; - sp->srcu_gp_running = false; - sp->srcu_gp_waiting = false; - sp->srcu_idx = 0; - INIT_WORK(&sp->srcu_work, srcu_drive_gp); - INIT_LIST_HEAD(&sp->srcu_work.entry); + ssp->srcu_lock_nesting[0] = 0; + ssp->srcu_lock_nesting[1] = 0; + init_swait_queue_head(&ssp->srcu_wq); + ssp->srcu_cb_head = NULL; + ssp->srcu_cb_tail = &ssp->srcu_cb_head; + ssp->srcu_gp_running = false; + ssp->srcu_gp_waiting = false; + ssp->srcu_idx = 0; + INIT_WORK(&ssp->srcu_work, srcu_drive_gp); + INIT_LIST_HEAD(&ssp->srcu_work.entry); return 0; } #ifdef CONFIG_DEBUG_LOCK_ALLOC -int __init_srcu_struct(struct srcu_struct *sp, const char *name, +int __init_srcu_struct(struct srcu_struct *ssp, const char *name, struct lock_class_key *key) { /* Don't re-initialize a lock while it is held. */ - debug_check_no_locks_freed((void *)sp, sizeof(*sp)); - lockdep_init_map(&sp->dep_map, name, key, 0); - return init_srcu_struct_fields(sp); + debug_check_no_locks_freed((void *)ssp, sizeof(*ssp)); + lockdep_init_map(&ssp->dep_map, name, key, 0); + return init_srcu_struct_fields(ssp); } EXPORT_SYMBOL_GPL(__init_srcu_struct); @@ -68,15 +68,15 @@ EXPORT_SYMBOL_GPL(__init_srcu_struct); /* * init_srcu_struct - initialize a sleep-RCU structure - * @sp: structure to initialize. + * @ssp: structure to initialize. * * Must invoke this on a given srcu_struct before passing that srcu_struct * to any other function. Each srcu_struct represents a separate domain * of SRCU protection. */ -int init_srcu_struct(struct srcu_struct *sp) +int init_srcu_struct(struct srcu_struct *ssp) { - return init_srcu_struct_fields(sp); + return init_srcu_struct_fields(ssp); } EXPORT_SYMBOL_GPL(init_srcu_struct); @@ -84,22 +84,22 @@ EXPORT_SYMBOL_GPL(init_srcu_struct); /* * cleanup_srcu_struct - deconstruct a sleep-RCU structure - * @sp: structure to clean up. + * @ssp: structure to clean up. * * Must invoke this after you are finished using a given srcu_struct that * was initialized via init_srcu_struct(), else you leak memory. */ -void _cleanup_srcu_struct(struct srcu_struct *sp, bool quiesced) +void _cleanup_srcu_struct(struct srcu_struct *ssp, bool quiesced) { - WARN_ON(sp->srcu_lock_nesting[0] || sp->srcu_lock_nesting[1]); + WARN_ON(ssp->srcu_lock_nesting[0] || ssp->srcu_lock_nesting[1]); if (quiesced) - WARN_ON(work_pending(&sp->srcu_work)); + WARN_ON(work_pending(&ssp->srcu_work)); else - flush_work(&sp->srcu_work); - WARN_ON(sp->srcu_gp_running); - WARN_ON(sp->srcu_gp_waiting); - WARN_ON(sp->srcu_cb_head); - WARN_ON(&sp->srcu_cb_head != sp->srcu_cb_tail); + flush_work(&ssp->srcu_work); + WARN_ON(ssp->srcu_gp_running); + WARN_ON(ssp->srcu_gp_waiting); + WARN_ON(ssp->srcu_cb_head); + WARN_ON(&ssp->srcu_cb_head != ssp->srcu_cb_tail); } EXPORT_SYMBOL_GPL(_cleanup_srcu_struct); @@ -107,13 +107,13 @@ EXPORT_SYMBOL_GPL(_cleanup_srcu_struct); * Removes the count for the old reader from the appropriate element of * the srcu_struct. */ -void __srcu_read_unlock(struct srcu_struct *sp, int idx) +void __srcu_read_unlock(struct srcu_struct *ssp, int idx) { - int newval = sp->srcu_lock_nesting[idx] - 1; + int newval = ssp->srcu_lock_nesting[idx] - 1; - WRITE_ONCE(sp->srcu_lock_nesting[idx], newval); - if (!newval && READ_ONCE(sp->srcu_gp_waiting)) - swake_up_one(&sp->srcu_wq); + WRITE_ONCE(ssp->srcu_lock_nesting[idx], newval); + if (!newval && READ_ONCE(ssp->srcu_gp_waiting)) + swake_up_one(&ssp->srcu_wq); } EXPORT_SYMBOL_GPL(__srcu_read_unlock); @@ -127,24 +127,24 @@ void srcu_drive_gp(struct work_struct *wp) int idx; struct rcu_head *lh; struct rcu_head *rhp; - struct srcu_struct *sp; + struct srcu_struct *ssp; - sp = container_of(wp, struct srcu_struct, srcu_work); - if (sp->srcu_gp_running || !READ_ONCE(sp->srcu_cb_head)) + ssp = container_of(wp, struct srcu_struct, srcu_work); + if (ssp->srcu_gp_running || !READ_ONCE(ssp->srcu_cb_head)) return; /* Already running or nothing to do. */ /* Remove recently arrived callbacks and wait for readers. */ - WRITE_ONCE(sp->srcu_gp_running, true); + WRITE_ONCE(ssp->srcu_gp_running, true); local_irq_disable(); - lh = sp->srcu_cb_head; - sp->srcu_cb_head = NULL; - sp->srcu_cb_tail = &sp->srcu_cb_head; + lh = ssp->srcu_cb_head; + ssp->srcu_cb_head = NULL; + ssp->srcu_cb_tail = &ssp->srcu_cb_head; local_irq_enable(); - idx = sp->srcu_idx; - WRITE_ONCE(sp->srcu_idx, !sp->srcu_idx); - WRITE_ONCE(sp->srcu_gp_waiting, true); /* srcu_read_unlock() wakes! */ - swait_event_exclusive(sp->srcu_wq, !READ_ONCE(sp->srcu_lock_nesting[idx])); - WRITE_ONCE(sp->srcu_gp_waiting, false); /* srcu_read_unlock() cheap. */ + idx = ssp->srcu_idx; + WRITE_ONCE(ssp->srcu_idx, !ssp->srcu_idx); + WRITE_ONCE(ssp->srcu_gp_waiting, true); /* srcu_read_unlock() wakes! */ + swait_event_exclusive(ssp->srcu_wq, !READ_ONCE(ssp->srcu_lock_nesting[idx])); + WRITE_ONCE(ssp->srcu_gp_waiting, false); /* srcu_read_unlock() cheap. */ /* Invoke the callbacks we removed above. */ while (lh) { @@ -161,9 +161,9 @@ void srcu_drive_gp(struct work_struct *wp) * at interrupt level, but the ->srcu_gp_running checks will * straighten that out. */ - WRITE_ONCE(sp->srcu_gp_running, false); - if (READ_ONCE(sp->srcu_cb_head)) - schedule_work(&sp->srcu_work); + WRITE_ONCE(ssp->srcu_gp_running, false); + if (READ_ONCE(ssp->srcu_cb_head)) + schedule_work(&ssp->srcu_work); } EXPORT_SYMBOL_GPL(srcu_drive_gp); @@ -171,7 +171,7 @@ EXPORT_SYMBOL_GPL(srcu_drive_gp); * Enqueue an SRCU callback on the specified srcu_struct structure, * initiating grace-period processing if it is not already running. */ -void call_srcu(struct srcu_struct *sp, struct rcu_head *rhp, +void call_srcu(struct srcu_struct *ssp, struct rcu_head *rhp, rcu_callback_t func) { unsigned long flags; @@ -179,14 +179,14 @@ void call_srcu(struct srcu_struct *sp, struct rcu_head *rhp, rhp->func = func; rhp->next = NULL; local_irq_save(flags); - *sp->srcu_cb_tail = rhp; - sp->srcu_cb_tail = &rhp->next; + *ssp->srcu_cb_tail = rhp; + ssp->srcu_cb_tail = &rhp->next; local_irq_restore(flags); - if (!READ_ONCE(sp->srcu_gp_running)) { + if (!READ_ONCE(ssp->srcu_gp_running)) { if (likely(srcu_init_done)) - schedule_work(&sp->srcu_work); - else if (list_empty(&sp->srcu_work.entry)) - list_add(&sp->srcu_work.entry, &srcu_boot_list); + schedule_work(&ssp->srcu_work); + else if (list_empty(&ssp->srcu_work.entry)) + list_add(&ssp->srcu_work.entry, &srcu_boot_list); } } EXPORT_SYMBOL_GPL(call_srcu); @@ -194,13 +194,13 @@ EXPORT_SYMBOL_GPL(call_srcu); /* * synchronize_srcu - wait for prior SRCU read-side critical-section completion */ -void synchronize_srcu(struct srcu_struct *sp) +void synchronize_srcu(struct srcu_struct *ssp) { struct rcu_synchronize rs; init_rcu_head_on_stack(&rs.head); init_completion(&rs.completion); - call_srcu(sp, &rs.head, wakeme_after_rcu); + call_srcu(ssp, &rs.head, wakeme_after_rcu); wait_for_completion(&rs.completion); destroy_rcu_head_on_stack(&rs.head); } @@ -219,13 +219,13 @@ void __init rcu_scheduler_starting(void) */ void __init srcu_init(void) { - struct srcu_struct *sp; + struct srcu_struct *ssp; srcu_init_done = true; while (!list_empty(&srcu_boot_list)) { - sp = list_first_entry(&srcu_boot_list, + ssp = list_first_entry(&srcu_boot_list, struct srcu_struct, srcu_work.entry); - list_del_init(&sp->srcu_work.entry); - schedule_work(&sp->srcu_work); + list_del_init(&ssp->srcu_work.entry); + schedule_work(&ssp->srcu_work); } } -- cgit