diff mbox series

[21/48] rcu: Remove redundant BH disabling in TINY_RCU

Message ID	20240507093530.3043-22-urezki@gmail.com (mailing list archive)
State	Mainlined
Commit	3dbd8652f87b81fccb766bddb985ef46a1502f04
Headers	show Received: from mail-lj1-f175.google.com (mail-lj1-f175.google.com [209.85.208.175]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D956215E1E5; Tue, 7 May 2024 09:35:54 +0000 (UTC) From: "Uladzislau Rezki (Sony)" <urezki@gmail.com> To: "Paul E . McKenney" <paulmck@kernel.org> Cc: RCU <rcu@vger.kernel.org>, Neeraj upadhyay <Neeraj.Upadhyay@amd.com>, Boqun Feng <boqun.feng@gmail.com>, Hillf Danton <hdanton@sina.com>, Joel Fernandes <joel@joelfernandes.org>, LKML <linux-kernel@vger.kernel.org>, Uladzislau Rezki <urezki@gmail.com>, Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>, Frederic Weisbecker <frederic@kernel.org> Subject: [PATCH 21/48] rcu: Remove redundant BH disabling in TINY_RCU Date: Tue, 7 May 2024 11:35:03 +0200 Message-Id: <20240507093530.3043-22-urezki@gmail.com> In-Reply-To: <20240507093530.3043-1-urezki@gmail.com> References: <20240507093530.3043-1-urezki@gmail.com> Precedence: bulk MIME-Version: 1.0 Content-Transfer-Encoding: 8bit
Series	RCU changes for v6.10 \| expand [00/48] RCU changes for v6.10 [01/48] scftorture: Increase memory provided to guest OS [02/48] rcutorture: Disable tracing to permit Tasks Rude RCU testing [03/48] rcu: Add lockdep checks and kernel-doc header to rcu_softirq_qs() [04/48] rcutorture: Enable RCU priority boosting for TREE09 [05/48] rcutorture: Dump # online CPUs on insufficient cb-flood laundering [06/48] rcutorture: Dump GP kthread state on insufficient cb-flood laundering [07/48] rcutorture: ASSERT_EXCLUSIVE_WRITER() for ->rtort_pipe_count updates [08/48] rcu-tasks: Make Tasks RCU wait idly for grace-period delays [09/48] doc: Remove references to arrayRCU.rst [10/48] MAINTAINERS: Update Neeraj's email address [11/48] bpf: Select new NEED_TASKS_RCU Kconfig option [12/48] arch: Select new NEED_TASKS_RCU Kconfig option [13/48] rcu: Add data structures for synchronize_rcu() [14/48] tracing: Select new NEED_TASKS_RCU Kconfig option [15/48] bpf: Choose RCU Tasks based on TASKS_RCU rather than PREEMPTION [16/48] ftrace: Choose RCU Tasks based on TASKS_RCU rather than PREEMPTION [17/48] rcu: Update lockdep while in RCU read-side critical section [18/48] rcu: Make TINY_RCU depend on !PREEMPT_RCU rather than !PREEMPTION [19/48] srcu: Make Tiny SRCU explicitly disable preemption [20/48] rcu: Create NEED_TASKS_RCU to factor out enablement logic [21/48] rcu: Remove redundant BH disabling in TINY_RCU [22/48] rcu: Make Tiny RCU explicitly disable preemption [23/48] rcu: Remove redundant READ_ONCE() of rcu_state.gp_flags in tree.c [24/48] rcu: Bring diagnostic read of rcu_state.gp_flags into alignment [25/48] rcu: Mark writes to rcu_sync ->gp_count field [26/48] rcu: Mark loads from rcu_state.n_online_cpus [27/48] rcu: Make hotplug operations track GP state, not flags [28/48] rcu: Inform KCSAN of one-byte cmpxchg() in rcu_trc_cmpxchg_need_qs() [29/48] rcu: Remove redundant CONFIG_PROVE_RCU #if condition [30/48] rcu-tasks: Replace exit_tasks_rcu_start() initialization with WARN_ON_ONCE() [31/48] rcu-tasks: Fix the comments for tasks_rcu_exit_srcu_stall_timer [32/48] rcu-tasks: Fix show_rcu_tasks_trace_gp_kthread buffer overflow [33/48] rcu: Mollify sparse with RCU guard [34/48] rcu: Fix buffer overflow in print_cpu_stall_info() [35/48] rcu: Reduce synchronize_rcu() latency [36/48] rcu: Add a trace event for synchronize_rcu_normal() [37/48] rcu: Support direct wake-up of synchronize_rcu() users [38/48] rcu: Allocate WQ with WQ_MEM_RECLAIM bit set [39/48] rcutorture: Remove extraneous rcu_torture_pipe_update_one() READ_ONCE() [40/48] rcutorture: Fix rcu_torture_one_read() pipe_count overflow comment [41/48] rcutorture: Re-use value stored to ->rtort_pipe_count instead of re-reading [42/48] rcutorture: Use the gp_kthread_dbg operation specified by cur_ops [43/48] rcutorture: Make rcutorture support print rcu-tasks gp state [44/48] rcutorture: Removing redundant function pointer initialization [45/48] rcutorture: Make stall-tasks directly exit when rcutorture tests end [46/48] rcutorture: Fix invalid context warning when enable srcu barrier testing [47/48] torture: Scale --do-kvfree test time [48/48] rcutorture: Use rcu_gp_slow_register/unregister() only for rcutype test

Commit Message

Uladzislau Rezki May 7, 2024, 9:35 a.m. UTC

From: "Paul E. McKenney" <paulmck@kernel.org>

The TINY_RCU rcu_process_callbacks() function is only ever invoked from
a softirq handler, which means that BH is already disabled.  This commit
therefore removes the redundant local_bh_disable() and local_bh_ennable()
from this function.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
---
 kernel/rcu/tiny.c | 2 --
 1 file changed, 2 deletions(-)

diff mbox series

Patch

diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c
index 705c0d16850a..4470af926a34 100644
--- a/kernel/rcu/tiny.c
+++ b/kernel/rcu/tiny.c
@@ -130,9 +130,7 @@  static __latent_entropy void rcu_process_callbacks(struct softirq_action *unused
 		next = list->next;
 		prefetch(next);
 		debug_rcu_head_unqueue(list);
-		local_bh_disable();
 		rcu_reclaim_tiny(list);
-		local_bh_enable();
 		list = next;
 	}
 }