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 07/27] rcu: Inline rcu_dynticks_momentary_idle() into its sole caller
Date: Mon, 25 Jun 2018 17:34:53 -0700 [thread overview]
Message-ID: <20180626003513.27812-7-paulmck@linux.vnet.ibm.com> (raw)
In-Reply-To: <20180626003448.GA26209@linux.vnet.ibm.com>
The rcu_dynticks_momentary_idle() function is invoked only from
rcu_momentary_dyntick_idle(), and neither function is particularly
large. This commit therefore saves a few lines by inlining
rcu_dynticks_momentary_idle() into rcu_momentary_dyntick_idle().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
kernel/rcu/tree.c | 23 +++++++----------------
1 file changed, 7 insertions(+), 16 deletions(-)
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 1ea971244512..98f51157f735 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -385,20 +385,6 @@ static bool rcu_dynticks_in_eqs_since(struct rcu_dynticks *rdtp, int snap)
return snap != rcu_dynticks_snap(rdtp);
}
-/*
- * Do a double-increment of the ->dynticks counter to emulate a
- * momentary idle-CPU quiescent state.
- */
-static void rcu_dynticks_momentary_idle(void)
-{
- struct rcu_dynticks *rdtp = this_cpu_ptr(&rcu_dynticks);
- int special = atomic_add_return(2 * RCU_DYNTICK_CTRL_CTR,
- &rdtp->dynticks);
-
- /* It is illegal to call this from idle state. */
- WARN_ON_ONCE(!(special & RCU_DYNTICK_CTRL_CTR));
-}
-
/*
* Set the special (bottom) bit of the specified CPU so that it
* will take special action (such as flushing its TLB) on the
@@ -430,12 +416,17 @@ bool rcu_eqs_special_set(int cpu)
*
* We inform the RCU core by emulating a zero-duration dyntick-idle period.
*
- * The caller must have disabled interrupts.
+ * The caller must have disabled interrupts and must not be idle.
*/
static void rcu_momentary_dyntick_idle(void)
{
+ struct rcu_dynticks *rdtp = this_cpu_ptr(&rcu_dynticks);
+ int special;
+
raw_cpu_write(rcu_dynticks.rcu_need_heavy_qs, false);
- rcu_dynticks_momentary_idle();
+ special = atomic_add_return(2 * RCU_DYNTICK_CTRL_CTR, &rdtp->dynticks);
+ /* It is illegal to call this from idle state. */
+ WARN_ON_ONCE(!(special & RCU_DYNTICK_CTRL_CTR));
}
/*
--
2.17.1
next prev parent reply other threads:[~2018-06-26 0:36 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-26 0:34 [PATCH tip/core/rcu 0/27] Post-gp_seq miscellaneous fixes for v4.19 Paul E. McKenney
2018-06-26 0:34 ` [PATCH tip/core/rcu 01/27] rcu: Make rcu_read_unlock_special() static Paul E. McKenney
2018-06-26 0:34 ` [PATCH tip/core/rcu 02/27] rcu: Improve rcu_note_voluntary_context_switch() reporting Paul E. McKenney
2018-06-26 0:34 ` [PATCH tip/core/rcu 03/27] rcu: rcupdate.h: Get rid of Sphinx warnings at rcu_pointer_handoff() Paul E. McKenney
2018-06-26 0:34 ` [PATCH tip/core/rcu 04/27] rcu: Use pr_fmt to prefix "rcu: " to logging output Paul E. McKenney
2018-06-26 0:34 ` [PATCH tip/core/rcu 05/27] rcu: Improve RCU-tasks naming and comments Paul E. McKenney
2018-06-26 0:34 ` [PATCH tip/core/rcu 06/27] rcu: Mark task as .need_qs less aggressively Paul E. McKenney
2018-06-26 17:08 ` Peter Zijlstra
2018-06-26 18:03 ` Paul E. McKenney
2018-06-26 21:38 ` Paul E. McKenney
2018-06-26 0:34 ` Paul E. McKenney [this message]
2018-06-26 0:34 ` [PATCH tip/core/rcu 08/27] rcu: Clarify and correct the rcu_preempt_qs() header comment Paul E. McKenney
2018-06-26 0:34 ` [PATCH tip/core/rcu 09/27] rcu: Remove unused rcu_kick_nohz_cpu() function Paul E. McKenney
2018-06-26 0:34 ` [PATCH tip/core/rcu 10/27] rcu: Remove unused local variable "cpu" Paul E. McKenney
2018-06-26 0:34 ` [PATCH tip/core/rcu 11/27] rcu: Remove "inline" from panic_on_rcu_stall() and rcu_blocking_is_gp() Paul E. McKenney
2018-06-26 0:34 ` [PATCH tip/core/rcu 12/27] rcu: Remove "inline" from rcu_torture_print_module_parms() Paul E. McKenney
2018-06-26 0:34 ` [PATCH tip/core/rcu 13/27] rcu: Remove "inline" from rcu_perf_print_module_parms() Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 14/27] rcu: Remove __maybe_unused from rcu_cpu_has_callbacks() Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 15/27] rcu: Use RCU CPU stall timeout for rcu_check_gp_start_stall() Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 16/27] rcu: Add comment documenting how rcu_seq_snap works Paul E. McKenney
2018-06-26 17:14 ` Peter Zijlstra
2018-06-26 18:08 ` Paul E. McKenney
2018-06-26 19:21 ` Peter Zijlstra
2018-06-26 19:31 ` Paul E. McKenney
2018-06-26 20:15 ` Peter Zijlstra
2018-06-26 22:27 ` Paul E. McKenney
2018-06-26 17:30 ` Peter Zijlstra
2018-06-26 18:10 ` Paul E. McKenney
2018-06-26 19:27 ` Peter Zijlstra
2018-06-27 4:39 ` Joel Fernandes
2018-06-27 17:54 ` Paul E. McKenney
2018-06-27 18:27 ` Joel Fernandes
2018-06-27 19:11 ` Paul E. McKenney
2018-06-28 5:10 ` Joel Fernandes
2018-06-28 17:42 ` Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 17/27] rcu: Speed up calling of RCU tasks callbacks Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 18/27] rcu: Add comment to the last sleep in the rcu tasks loop Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 19/27] rcu: Add diagnostics for rcutorture writer stall warning Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 20/27] rcu: Check the range of jiffies_till_{first,next}_fqs when setting them Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 21/27] doc: Update synchronize_rcu() definition in whatisRCU.txt Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 22/27] rcu: Make rcu_seq_diff() more exact Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 23/27] MAINTAINERS: Update RCU, SRCU, and TORTURE-TEST entries Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 24/27] rcu: Print stall-warning NMI dyntick state in hexadecimal Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 25/27] srcu: Add grace-period number to rcutorture statistics printout Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 26/27] rculist: Improve documentation for list_for_each_entry_from_rcu() Paul E. McKenney
2018-06-26 0:35 ` [PATCH tip/core/rcu 27/27] rcu: Assign higher prio to RCU threads if rcutorture is built-in 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=20180626003513.27812-7-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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®