Netdev Archive on lore.kernel.org
 help / color / Atom feed
From: "Joel Fernandes (Google)" <joel@joelfernandes.org>
To: linux-kernel@vger.kernel.org
Cc: "Joel Fernandes (Google)" <joel@joelfernandes.org>,
	Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Borislav Petkov <bp@alien8.de>,
	c0d1n61at3@gmail.com, "David S. Miller" <davem@davemloft.net>,
	edumazet@google.com,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
	"H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
	Jonathan Corbet <corbet@lwn.net>,
	Josh Triplett <josh@joshtriplett.org>,
	keescook@chromium.org, kernel-hardening@lists.openwall.com,
	kernel-team@android.com, Lai Jiangshan <jiangshanlai@gmail.com>,
	Len Brown <lenb@kernel.org>,
	linux-acpi@vger.kernel.org, linux-doc@vger.kernel.org,
	linux-pci@vger.kernel.org, linux-pm@vger.kernel.org,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	neilb@suse.com, netdev@vger.kernel.org,
	Oleg Nesterov <oleg@redhat.com>,
	"Paul E. McKenney" <paulmck@linux.ibm.com>,
	Pavel Machek <pavel@ucw.cz>,
	peterz@infradead.org, "Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Rasmus Villemoes <rasmus.villemoes@prevas.dk>,
	rcu@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>,
	Tejun Heo <tj@kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
	will@kernel.org,
	x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT))
Subject: [PATCH v2 1/9] rcu/update: Remove useless check for debug_locks
Date: Fri, 12 Jul 2019 13:00:16 -0400
Message-ID: <20190712170024.111093-2-joel@joelfernandes.org> (raw)
In-Reply-To: <20190712170024.111093-1-joel@joelfernandes.org>

In rcu_read_lock_sched_held(), debug_locks can never be true at the
point we check it because we already check debug_locks in
debug_lockdep_rcu_enabled() in the beginning. Remove the check.

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
---
 kernel/rcu/update.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index c3bf44ba42e5..bb961cd89e76 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -93,17 +93,13 @@ module_param(rcu_normal_after_boot, int, 0);
  */
 int rcu_read_lock_sched_held(void)
 {
-	int lockdep_opinion = 0;
-
 	if (!debug_lockdep_rcu_enabled())
 		return 1;
 	if (!rcu_is_watching())
 		return 0;
 	if (!rcu_lockdep_current_cpu_online())
 		return 0;
-	if (debug_locks)
-		lockdep_opinion = lock_is_held(&rcu_sched_lock_map);
-	return lockdep_opinion || !preemptible();
+	return lock_is_held(&rcu_sched_lock_map) || !preemptible();
 }
 EXPORT_SYMBOL(rcu_read_lock_sched_held);
 #endif
-- 
2.22.0.510.g264f2c817a-goog


  reply index

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-12 17:00 [PATCH v2 0/9] Harden list_for_each_entry_rcu() and family Joel Fernandes (Google)
2019-07-12 17:00 ` Joel Fernandes (Google) [this message]
2019-07-12 17:00 ` [PATCH v2 2/9] rcu: Add support for consolidated-RCU reader checking Joel Fernandes (Google)
2019-07-16 18:22   ` Paul E. McKenney
2019-07-16 18:35     ` Joel Fernandes
2019-07-16 18:50       ` Paul E. McKenney
2019-07-12 17:00 ` [PATCH v2 3/9] rcu/sync: Remove custom check for reader-section Joel Fernandes (Google)
2019-07-12 21:35   ` Joel Fernandes
2019-07-12 23:32     ` Paul E. McKenney
2019-07-13  3:01       ` Joel Fernandes
2019-07-13  3:10         ` Joel Fernandes
2019-07-13  8:21           ` Paul E. McKenney
2019-07-13 13:30             ` Joel Fernandes
2019-07-13 14:41               ` Paul E. McKenney
2019-07-13 15:36                 ` Joel Fernandes
2019-07-13 15:50                   ` Paul E. McKenney
2019-07-13 16:13                     ` Joel Fernandes
2019-07-13 21:28                       ` Paul E. McKenney
2019-07-14 18:10                         ` Joel Fernandes
2019-07-14 18:38                           ` Joel Fernandes
2019-07-14 18:50                             ` Paul E. McKenney
2019-07-15  7:26           ` Oleg Nesterov
2019-07-16 18:26   ` Paul E. McKenney
2019-07-16 18:28     ` Paul E. McKenney
2019-07-12 17:00 ` [PATCH v2 4/9] ipv4: add lockdep condition to fix for_each_entry Joel Fernandes (Google)
2019-07-12 17:00 ` [PATCH v2 5/9] driver/core: Convert to use built-in RCU list checking Joel Fernandes (Google)
2019-07-12 17:00 ` [PATCH v2 6/9] workqueue: Convert for_each_wq to use built-in list check Joel Fernandes (Google)
2019-07-12 17:00 ` [PATCH v2 7/9] x86/pci: Pass lockdep condition to pcm_mmcfg_list iterator Joel Fernandes (Google)
2019-07-12 17:00 ` [PATCH v2 8/9] acpi: Use built-in RCU list checking for acpi_ioremaps list Joel Fernandes (Google)
2019-07-12 17:00 ` [PATCH v2 9/9] doc: Update documentation about list_for_each_entry_rcu Joel Fernandes (Google)

Reply instructions:

You may reply publically 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=20190712170024.111093-2-joel@joelfernandes.org \
    --to=joel@joelfernandes.org \
    --cc=bhelgaas@google.com \
    --cc=bp@alien8.de \
    --cc=c0d1n61at3@gmail.com \
    --cc=corbet@lwn.net \
    --cc=davem@davemloft.net \
    --cc=edumazet@google.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=hpa@zytor.com \
    --cc=jiangshanlai@gmail.com \
    --cc=josh@joshtriplett.org \
    --cc=keescook@chromium.org \
    --cc=kernel-hardening@lists.openwall.com \
    --cc=kernel-team@android.com \
    --cc=kuznet@ms2.inr.ac.ru \
    --cc=lenb@kernel.org \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=mathieu.desnoyers@efficios.com \
    --cc=mingo@redhat.com \
    --cc=neilb@suse.com \
    --cc=netdev@vger.kernel.org \
    --cc=oleg@redhat.com \
    --cc=paulmck@linux.ibm.com \
    --cc=pavel@ucw.cz \
    --cc=peterz@infradead.org \
    --cc=rasmus.villemoes@prevas.dk \
    --cc=rcu@vger.kernel.org \
    --cc=rjw@rjwysocki.net \
    --cc=rostedt@goodmis.org \
    --cc=tglx@linutronix.de \
    --cc=tj@kernel.org \
    --cc=will@kernel.org \
    --cc=x86@kernel.org \
    --cc=yoshfuji@linux-ipv6.org \
    /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

Netdev Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/netdev/0 netdev/git/0.git
	git clone --mirror https://lore.kernel.org/netdev/1 netdev/git/1.git

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

Example config snippet for mirrors

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


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