From: "Paul E. McKenney" <paulmck@kernel.org>
To: rcu@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com,
rostedt@goodmis.org, Lukas Bulwahn <lukas.bulwahn@gmail.com>,
"Paul E . McKenney" <paulmck@kernel.org>
Subject: [PATCH rcu 21/21] srcu: Drop needless initialization of sdp in srcu_gp_start()
Date: Mon, 18 Apr 2022 17:03:22 -0700 [thread overview]
Message-ID: <20220419000322.3948903-21-paulmck@kernel.org> (raw)
In-Reply-To: <20220419000315.GA3948789@paulmck-ThinkPad-P17-Gen-1>
From: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Commit 9c7ef4c30f12 ("srcu: Make Tree SRCU able to operate without
snp_node array") initializes the local variable sdp differently depending
on the srcu's state in srcu_gp_start(). Either way, this initialization
overwrites the value used when sdp is defined.
This commit therefore drops this pointless definition-time initialization.
Although there is no functional change, compiler code generation may
be affected.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
kernel/rcu/srcutree.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
index 6dd44e759f12..50ba70f019de 100644
--- a/kernel/rcu/srcutree.c
+++ b/kernel/rcu/srcutree.c
@@ -620,7 +620,7 @@ EXPORT_SYMBOL_GPL(__srcu_read_unlock);
*/
static void srcu_gp_start(struct srcu_struct *ssp)
{
- struct srcu_data *sdp = this_cpu_ptr(ssp->sda);
+ struct srcu_data *sdp;
int state;
if (smp_load_acquire(&ssp->srcu_size_state) < SRCU_SIZE_WAIT_BARRIER)
--
2.31.1.189.g2e36527f23
prev parent reply other threads:[~2022-04-19 0:05 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-19 0:03 [PATCH rcu 0/21] SRCU updates for v5.19 Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 01/21] srcu: Tighten cleanup_srcu_struct() GP checks Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 02/21] srcu: Fix s/is/if/ typo in srcu_node comment Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 03/21] srcu: Make srcu_funnel_gp_start() cache ->mynode in snp_leaf Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 04/21] srcu: Make Tree SRCU able to operate without snp_node array Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 05/21] srcu: Dynamically allocate srcu_node array Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 06/21] srcu: Add size-state transitioning code Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 07/21] srcu: Make rcutorture dump the SRCU size state Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 08/21] srcu: Compute snp_seq earlier in srcu_funnel_gp_start() Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 09/21] srcu: Use invalid initial value for srcu_node GP sequence numbers Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 10/21] srcu: Ensure snp nodes tree is fully initialized before traversal Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 11/21] srcu: Add boot-time control over srcu_node array allocation Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 12/21] srcu: Use export for srcu_struct defined by DEFINE_STATIC_SRCU() Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 13/21] srcu: Avoid NULL dereference in srcu_torture_stats_print() Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 14/21] srcu: Prevent cleanup_srcu_struct() from freeing non-dynamic ->sda Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 15/21] srcu: Explain srcu_funnel_gp_start() call to list_add() is safe Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 16/21] srcu: Create concurrency-safe helper for initiating size transition Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 17/21] srcu: Add contention-triggered addition of srcu_node tree Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 18/21] srcu: Automatically determine size-transition strategy at boot Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 19/21] srcu: Add contention check to call_srcu() srcu_data ->lock acquisition Paul E. McKenney
2022-04-19 0:03 ` [PATCH rcu 20/21] srcu: Prevent expedited GPs and blocking readers from consuming CPU Paul E. McKenney
2022-04-19 0:03 ` Paul E. McKenney [this message]
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