LKML Archive on lore.kernel.org
 help / color / Atom feed
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: linux-kernel@vger.kernel.org
Cc: mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com,
	akpm@linux-foundation.org, mathieu.desnoyers@efficios.com,
	josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org,
	rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com,
	fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Subject: [PATCH tip/core/rcu 14/19] rcu: Express Tiny RCU updates in terms of RCU rather than RCU-sched
Date: Wed, 29 Aug 2018 15:20:42 -0700
Message-ID: <20180829222047.319-14-paulmck@linux.vnet.ibm.com> (raw)
In-Reply-To: <20180829222021.GA29944@linux.vnet.ibm.com>

This commit renames Tiny RCU functions so that the lowest level of
functionality is RCU (e.g., synchronize_rcu()) rather than RCU-sched
(e.g., synchronize_sched()).  This provides greater naming compatibility
with Tree RCU, which will in turn permit more LoC removal once
the RCU-sched and RCU-bh update-side API is removed.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Fix Tiny call_rcu()'s EXPORT_SYMBOL() in response to a bug
  report from kbuild test robot. ]
---
 include/linux/rcupdate.h | 12 +++++-----
 include/linux/rcutiny.h  | 34 +++++++++++++++-------------
 include/linux/rcutree.h  |  1 -
 kernel/rcu/tiny.c        | 48 ++++++++++++++++++++--------------------
 4 files changed, 48 insertions(+), 47 deletions(-)

diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index 94474bb6b5c4..1207c6c9bd8b 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -49,15 +49,14 @@
 
 /* Exported common interfaces */
 
-#ifdef CONFIG_TINY_RCU
-#define	call_rcu	call_rcu_sched
-#else
-void call_rcu(struct rcu_head *head, rcu_callback_t func);
+#ifndef CONFIG_TINY_RCU
+void synchronize_sched(void);
+void call_rcu_sched(struct rcu_head *head, rcu_callback_t func);
 #endif
 
-void call_rcu_sched(struct rcu_head *head, rcu_callback_t func);
-void synchronize_sched(void);
+void call_rcu(struct rcu_head *head, rcu_callback_t func);
 void rcu_barrier_tasks(void);
+void synchronize_rcu(void);
 
 static inline void call_rcu_bh(struct rcu_head *head, rcu_callback_t func)
 {
@@ -68,7 +67,6 @@ static inline void call_rcu_bh(struct rcu_head *head, rcu_callback_t func)
 
 void __rcu_read_lock(void);
 void __rcu_read_unlock(void);
-void synchronize_rcu(void);
 
 /*
  * Defined as a macro as it is a very low level header included from
diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h
index df2c0895c5e7..e66fb8bc2127 100644
--- a/include/linux/rcutiny.h
+++ b/include/linux/rcutiny.h
@@ -36,9 +36,9 @@ static inline int rcu_dynticks_snap(struct rcu_dynticks *rdtp)
 /* Never flag non-existent other CPUs! */
 static inline bool rcu_eqs_special_set(int cpu) { return false; }
 
-static inline void synchronize_rcu(void)
+static inline void synchronize_sched(void)
 {
-	synchronize_sched();
+	synchronize_rcu();
 }
 
 static inline unsigned long get_state_synchronize_rcu(void)
@@ -61,16 +61,11 @@ static inline void cond_synchronize_sched(unsigned long oldstate)
 	might_sleep();
 }
 
-static inline void synchronize_rcu_expedited(void)
-{
-	synchronize_sched();	/* Only one CPU, so pretty fast anyway!!! */
-}
+extern void rcu_barrier(void);
 
-extern void rcu_barrier_sched(void);
-
-static inline void rcu_barrier(void)
+static inline void rcu_barrier_sched(void)
 {
-	rcu_barrier_sched();  /* Only one CPU, so only one list of callbacks! */
+	rcu_barrier();  /* Only one CPU, so only one list of callbacks! */
 }
 
 static inline void rcu_barrier_bh(void)
@@ -88,27 +83,36 @@ static inline void synchronize_rcu_bh_expedited(void)
 	synchronize_sched();
 }
 
+static inline void synchronize_rcu_expedited(void)
+{
+	synchronize_sched();
+}
+
 static inline void synchronize_sched_expedited(void)
 {
 	synchronize_sched();
 }
 
-static inline void kfree_call_rcu(struct rcu_head *head,
-				  rcu_callback_t func)
+static inline void call_rcu_sched(struct rcu_head *head, rcu_callback_t func)
+{
+	call_rcu(head, func);
+}
+
+static inline void kfree_call_rcu(struct rcu_head *head, rcu_callback_t func)
 {
 	call_rcu(head, func);
 }
 
-void rcu_sched_qs(void);
+void rcu_qs(void);
 
 static inline void rcu_softirq_qs(void)
 {
-	rcu_sched_qs();
+	rcu_qs();
 }
 
 #define rcu_note_context_switch(preempt) \
 	do { \
-		rcu_sched_qs(); \
+		rcu_qs(); \
 		rcu_tasks_qs(current); \
 	} while (0)
 
diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h
index 0c44720f0e84..6d30a0809300 100644
--- a/include/linux/rcutree.h
+++ b/include/linux/rcutree.h
@@ -45,7 +45,6 @@ static inline void rcu_virt_note_context_switch(int cpu)
 	rcu_note_context_switch(false);
 }
 
-void synchronize_rcu(void);
 static inline void synchronize_rcu_bh(void)
 {
 	synchronize_rcu();
diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c
index cadcf63c4889..30826fb6e438 100644
--- a/kernel/rcu/tiny.c
+++ b/kernel/rcu/tiny.c
@@ -46,25 +46,25 @@ struct rcu_ctrlblk {
 };
 
 /* Definition for rcupdate control block. */
-static struct rcu_ctrlblk rcu_sched_ctrlblk = {
-	.donetail	= &rcu_sched_ctrlblk.rcucblist,
-	.curtail	= &rcu_sched_ctrlblk.rcucblist,
+static struct rcu_ctrlblk rcu_ctrlblk = {
+	.donetail	= &rcu_ctrlblk.rcucblist,
+	.curtail	= &rcu_ctrlblk.rcucblist,
 };
 
-void rcu_barrier_sched(void)
+void rcu_barrier(void)
 {
-	wait_rcu_gp(call_rcu_sched);
+	wait_rcu_gp(call_rcu);
 }
-EXPORT_SYMBOL(rcu_barrier_sched);
+EXPORT_SYMBOL(rcu_barrier);
 
 /* Record an rcu quiescent state.  */
-void rcu_sched_qs(void)
+void rcu_qs(void)
 {
 	unsigned long flags;
 
 	local_irq_save(flags);
-	if (rcu_sched_ctrlblk.donetail != rcu_sched_ctrlblk.curtail) {
-		rcu_sched_ctrlblk.donetail = rcu_sched_ctrlblk.curtail;
+	if (rcu_ctrlblk.donetail != rcu_ctrlblk.curtail) {
+		rcu_ctrlblk.donetail = rcu_ctrlblk.curtail;
 		raise_softirq(RCU_SOFTIRQ);
 	}
 	local_irq_restore(flags);
@@ -79,7 +79,7 @@ void rcu_sched_qs(void)
 void rcu_check_callbacks(int user)
 {
 	if (user)
-		rcu_sched_qs();
+		rcu_qs();
 }
 
 /* Invoke the RCU callbacks whose grace period has elapsed.  */
@@ -90,17 +90,17 @@ static __latent_entropy void rcu_process_callbacks(struct softirq_action *unused
 
 	/* Move the ready-to-invoke callbacks to a local list. */
 	local_irq_save(flags);
-	if (rcu_sched_ctrlblk.donetail == &rcu_sched_ctrlblk.rcucblist) {
+	if (rcu_ctrlblk.donetail == &rcu_ctrlblk.rcucblist) {
 		/* No callbacks ready, so just leave. */
 		local_irq_restore(flags);
 		return;
 	}
-	list = rcu_sched_ctrlblk.rcucblist;
-	rcu_sched_ctrlblk.rcucblist = *rcu_sched_ctrlblk.donetail;
-	*rcu_sched_ctrlblk.donetail = NULL;
-	if (rcu_sched_ctrlblk.curtail == rcu_sched_ctrlblk.donetail)
-		rcu_sched_ctrlblk.curtail = &rcu_sched_ctrlblk.rcucblist;
-	rcu_sched_ctrlblk.donetail = &rcu_sched_ctrlblk.rcucblist;
+	list = rcu_ctrlblk.rcucblist;
+	rcu_ctrlblk.rcucblist = *rcu_ctrlblk.donetail;
+	*rcu_ctrlblk.donetail = NULL;
+	if (rcu_ctrlblk.curtail == rcu_ctrlblk.donetail)
+		rcu_ctrlblk.curtail = &rcu_ctrlblk.rcucblist;
+	rcu_ctrlblk.donetail = &rcu_ctrlblk.rcucblist;
 	local_irq_restore(flags);
 
 	/* Invoke the callbacks on the local list. */
@@ -125,21 +125,21 @@ static __latent_entropy void rcu_process_callbacks(struct softirq_action *unused
  *
  * Cool, huh?  (Due to Josh Triplett.)
  */
-void synchronize_sched(void)
+void synchronize_rcu(void)
 {
 	RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map) ||
 			 lock_is_held(&rcu_lock_map) ||
 			 lock_is_held(&rcu_sched_lock_map),
 			 "Illegal synchronize_sched() in RCU read-side critical section");
 }
-EXPORT_SYMBOL_GPL(synchronize_sched);
+EXPORT_SYMBOL_GPL(synchronize_rcu);
 
 /*
  * Post an RCU callback to be invoked after the end of an RCU-sched grace
  * period.  But since we have but one CPU, that would be after any
  * quiescent state.
  */
-void call_rcu_sched(struct rcu_head *head, rcu_callback_t func)
+void call_rcu(struct rcu_head *head, rcu_callback_t func)
 {
 	unsigned long flags;
 
@@ -148,16 +148,16 @@ void call_rcu_sched(struct rcu_head *head, rcu_callback_t func)
 	head->next = NULL;
 
 	local_irq_save(flags);
-	*rcu_sched_ctrlblk.curtail = head;
-	rcu_sched_ctrlblk.curtail = &head->next;
+	*rcu_ctrlblk.curtail = head;
+	rcu_ctrlblk.curtail = &head->next;
 	local_irq_restore(flags);
 
 	if (unlikely(is_idle_task(current))) {
-		/* force scheduling for rcu_sched_qs() */
+		/* force scheduling for rcu_qs() */
 		resched_cpu(0);
 	}
 }
-EXPORT_SYMBOL_GPL(call_rcu_sched);
+EXPORT_SYMBOL_GPL(call_rcu);
 
 void __init rcu_init(void)
 {
-- 
2.17.1


  parent reply index

Thread overview: 49+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-08-29 22:20 [PATCH tip/core/rcu 0/19] RCU flavor-consolidation changes for v4.20/v5.0 Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 01/19] rcu: Refactor rcu_{nmi,irq}_{enter,exit}() Paul E. McKenney
2018-08-30 18:10   ` Steven Rostedt
2018-08-30 23:02     ` Paul E. McKenney
2018-08-31  2:25     ` Byungchul Park
2018-08-29 22:20 ` [PATCH tip/core/rcu 02/19] rcu: Defer reporting RCU-preempt quiescent states when disabled Paul E. McKenney
2018-10-29 11:24   ` Ran Rozenstein
2018-10-29 14:27     ` Paul E. McKenney
2018-10-30  3:44       ` Joel Fernandes
2018-10-30 12:58         ` Paul E. McKenney
2018-10-30 22:21           ` Joel Fernandes
2018-10-31 18:22             ` Paul E. McKenney
2018-11-02 19:43               ` Paul E. McKenney
2018-11-26 13:55                 ` Ran Rozenstein
2018-11-26 19:00                   ` Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 03/19] rcutorture: Test extended "rcu" read-side critical sections Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 04/19] rcu: Allow processing deferred QSes for exiting RCU-preempt readers Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 05/19] rcu: Remove now-unused ->b.exp_need_qs field from the rcu_special union Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 06/19] rcu: Add warning to detect half-interrupts Paul E. McKenney
2019-03-11 13:39   ` Joel Fernandes
2019-03-11 22:29     ` Paul E. McKenney
2019-03-12 15:05       ` Joel Fernandes
2019-03-12 15:20         ` Paul E. McKenney
2019-03-13 15:09           ` Joel Fernandes
2019-03-13 15:27             ` Steven Rostedt
2019-03-13 15:51               ` Paul E. McKenney
2019-03-13 16:51                 ` Steven Rostedt
2019-03-13 18:07                   ` Paul E. McKenney
2019-03-14 12:31                     ` Joel Fernandes
2019-03-14 13:36                       ` Steven Rostedt
2019-03-14 13:37                         ` Steven Rostedt
2019-03-14 21:27                           ` Joel Fernandes
2019-03-15  7:31     ` Byungchul Park
2019-03-15  7:44       ` Byungchul Park
2019-03-15 13:46         ` Joel Fernandes
2018-08-29 22:20 ` [PATCH tip/core/rcu 07/19] rcu: Apply RCU-bh QSes to RCU-sched and RCU-preempt when safe Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 08/19] rcu: Report expedited grace periods at context-switch time Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 09/19] rcu: Define RCU-bh update API in terms of RCU Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 10/19] rcu: Update comments and help text for no more RCU-bh updaters Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 11/19] rcu: Drop "wake" parameter from rcu_report_exp_rdp() Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 12/19] rcu: Fix typo in rcu_get_gp_kthreads_prio() header comment Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 13/19] rcu: Define RCU-sched API in terms of RCU for Tree RCU PREEMPT builds Paul E. McKenney
2018-08-29 22:20 ` Paul E. McKenney [this message]
2018-08-29 22:20 ` [PATCH tip/core/rcu 15/19] rcu: Remove RCU_STATE_INITIALIZER() Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 16/19] rcu: Eliminate rcu_state structure's ->call field Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 17/19] rcu: Remove rcu_state structure's ->rda field Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 18/19] rcu: Remove rcu_state_p pointer to default rcu_state structure Paul E. McKenney
2018-08-29 22:20 ` [PATCH tip/core/rcu 19/19] rcu: Remove rcu_data_p pointer to default rcu_data structure Paul E. McKenney
2018-08-29 22:22 ` [PATCH tip/core/rcu 0/19] RCU flavor-consolidation changes for v4.20/v5.0 Paul E. McKenney

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180829222047.319-14-paulmck@linux.vnet.ibm.com \
    --to=paulmck@linux.vnet.ibm.com \
    --cc=akpm@linux-foundation.org \
    --cc=dhowells@redhat.com \
    --cc=dipankar@in.ibm.com \
    --cc=edumazet@google.com \
    --cc=fweisbec@gmail.com \
    --cc=jiangshanlai@gmail.com \
    --cc=joel@joelfernandes.org \
    --cc=josh@joshtriplett.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mathieu.desnoyers@efficios.com \
    --cc=mingo@kernel.org \
    --cc=oleg@redhat.com \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

LKML Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/lkml/0 lkml/git/0.git
	git clone --mirror https://lore.kernel.org/lkml/1 lkml/git/1.git
	git clone --mirror https://lore.kernel.org/lkml/2 lkml/git/2.git
	git clone --mirror https://lore.kernel.org/lkml/3 lkml/git/3.git
	git clone --mirror https://lore.kernel.org/lkml/4 lkml/git/4.git
	git clone --mirror https://lore.kernel.org/lkml/5 lkml/git/5.git
	git clone --mirror https://lore.kernel.org/lkml/6 lkml/git/6.git
	git clone --mirror https://lore.kernel.org/lkml/7 lkml/git/7.git
	git clone --mirror https://lore.kernel.org/lkml/8 lkml/git/8.git
	git clone --mirror https://lore.kernel.org/lkml/9 lkml/git/9.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 lkml lkml/ https://lore.kernel.org/lkml \
		linux-kernel@vger.kernel.org
	public-inbox-index lkml

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-kernel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git