From: Gao Xiang <hsiangkao@linux.alibaba.com>
To: paulmck@kernel.org
Cc: kernel-team@android.com, Will Shiu <Will.Shiu@mediatek.com>,
linux-erofs@lists.ozlabs.org,
Frederic Weisbecker <frederic@kernel.org>,
Lai Jiangshan <jiangshanlai@gmail.com>,
Josh Triplett <josh@joshtriplett.org>,
Steven Rostedt <rostedt@goodmis.org>,
linux-kernel@vger.kernel.org, rcu@vger.kernel.org,
Matthias Brugger <matthias.bgg@gmail.com>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Joel Fernandes <joel@joelfernandes.org>,
linux-mediatek@lists.infradead.org,
Zqiang <qiang.zhang1211@gmail.com>,
Neeraj Upadhyay <quic_neeraju@quicinc.com>,
Boqun Feng <boqun.feng@gmail.com>,
linux-arm-kernel@lists.infradead.org,
AngeloGioacchino Del Regno
<angelogioacchino.delregno@collabora.com>
Subject: Re: [PATCH v1] rcu: Fix and improve RCU read lock checks when !CONFIG_DEBUG_LOCK_ALLOC
Date: Thu, 13 Jul 2023 12:51:34 +0800 [thread overview]
Message-ID: <a7078657-823f-6283-bfeb-b5dc2c4c8d09@linux.alibaba.com> (raw)
In-Reply-To: <0d9e7b4d-6477-47a6-b3d2-2c9d9b64903d@paulmck-laptop>
On 2023/7/13 12:27, Paul E. McKenney wrote:
> On Thu, Jul 13, 2023 at 10:02:17AM +0800, Gao Xiang wrote:
>>
>>
... sorry forget some.
>
> One additional question... What is your plan for kernels built with
> CONFIG_PREEMPT_COUNT=n? After all, in such kernels, there is no way
> that I know of for code to determine whether it is in an RCU read-side
> critical section, holding a spinlock, or running with preemption disabled.
I'm not sure if Android (or all targetted) users use or care about
this configuration (CONFIG_PREEMPT_COUNT=n), personally I think
for such configuration we could just fall back to the workqueue
approach all the time.
Anyway, such optimization really comes from real workloads /
experience, users don't live well without such mitigation.
Thanks,
Gao Xiang
>
> Thanx, Paul
WARNING: multiple messages have this Message-ID (diff)
From: Gao Xiang <hsiangkao@linux.alibaba.com>
To: paulmck@kernel.org
Cc: Joel Fernandes <joel@joelfernandes.org>,
Sandeep Dhavale <dhavale@google.com>,
Frederic Weisbecker <frederic@kernel.org>,
Neeraj Upadhyay <quic_neeraju@quicinc.com>,
Josh Triplett <josh@joshtriplett.org>,
Boqun Feng <boqun.feng@gmail.com>,
Steven Rostedt <rostedt@goodmis.org>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Lai Jiangshan <jiangshanlai@gmail.com>,
Zqiang <qiang.zhang1211@gmail.com>,
Matthias Brugger <matthias.bgg@gmail.com>,
AngeloGioacchino Del Regno
<angelogioacchino.delregno@collabora.com>,
linux-erofs@lists.ozlabs.org, xiang@kernel.org,
Will Shiu <Will.Shiu@mediatek.com>,
kernel-team@android.com, rcu@vger.kernel.org,
linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
linux-mediatek@lists.infradead.org
Subject: Re: [PATCH v1] rcu: Fix and improve RCU read lock checks when !CONFIG_DEBUG_LOCK_ALLOC
Date: Thu, 13 Jul 2023 12:51:34 +0800 [thread overview]
Message-ID: <a7078657-823f-6283-bfeb-b5dc2c4c8d09@linux.alibaba.com> (raw)
In-Reply-To: <0d9e7b4d-6477-47a6-b3d2-2c9d9b64903d@paulmck-laptop>
On 2023/7/13 12:27, Paul E. McKenney wrote:
> On Thu, Jul 13, 2023 at 10:02:17AM +0800, Gao Xiang wrote:
>>
>>
... sorry forget some.
>
> One additional question... What is your plan for kernels built with
> CONFIG_PREEMPT_COUNT=n? After all, in such kernels, there is no way
> that I know of for code to determine whether it is in an RCU read-side
> critical section, holding a spinlock, or running with preemption disabled.
I'm not sure if Android (or all targetted) users use or care about
this configuration (CONFIG_PREEMPT_COUNT=n), personally I think
for such configuration we could just fall back to the workqueue
approach all the time.
Anyway, such optimization really comes from real workloads /
experience, users don't live well without such mitigation.
Thanks,
Gao Xiang
>
> Thanx, Paul
WARNING: multiple messages have this Message-ID (diff)
From: Gao Xiang <hsiangkao@linux.alibaba.com>
To: paulmck@kernel.org
Cc: Joel Fernandes <joel@joelfernandes.org>,
Sandeep Dhavale <dhavale@google.com>,
Frederic Weisbecker <frederic@kernel.org>,
Neeraj Upadhyay <quic_neeraju@quicinc.com>,
Josh Triplett <josh@joshtriplett.org>,
Boqun Feng <boqun.feng@gmail.com>,
Steven Rostedt <rostedt@goodmis.org>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Lai Jiangshan <jiangshanlai@gmail.com>,
Zqiang <qiang.zhang1211@gmail.com>,
Matthias Brugger <matthias.bgg@gmail.com>,
AngeloGioacchino Del Regno
<angelogioacchino.delregno@collabora.com>,
linux-erofs@lists.ozlabs.org, xiang@kernel.org,
Will Shiu <Will.Shiu@mediatek.com>,
kernel-team@android.com, rcu@vger.kernel.org,
linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
linux-mediatek@lists.infradead.org
Subject: Re: [PATCH v1] rcu: Fix and improve RCU read lock checks when !CONFIG_DEBUG_LOCK_ALLOC
Date: Thu, 13 Jul 2023 12:51:34 +0800 [thread overview]
Message-ID: <a7078657-823f-6283-bfeb-b5dc2c4c8d09@linux.alibaba.com> (raw)
In-Reply-To: <0d9e7b4d-6477-47a6-b3d2-2c9d9b64903d@paulmck-laptop>
On 2023/7/13 12:27, Paul E. McKenney wrote:
> On Thu, Jul 13, 2023 at 10:02:17AM +0800, Gao Xiang wrote:
>>
>>
... sorry forget some.
>
> One additional question... What is your plan for kernels built with
> CONFIG_PREEMPT_COUNT=n? After all, in such kernels, there is no way
> that I know of for code to determine whether it is in an RCU read-side
> critical section, holding a spinlock, or running with preemption disabled.
I'm not sure if Android (or all targetted) users use or care about
this configuration (CONFIG_PREEMPT_COUNT=n), personally I think
for such configuration we could just fall back to the workqueue
approach all the time.
Anyway, such optimization really comes from real workloads /
experience, users don't live well without such mitigation.
Thanks,
Gao Xiang
>
> Thanx, Paul
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2023-07-13 4:51 UTC|newest]
Thread overview: 117+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-11 23:38 [PATCH v1] rcu: Fix and improve RCU read lock checks when !CONFIG_DEBUG_LOCK_ALLOC Sandeep Dhavale via Linux-erofs
2023-07-11 23:38 ` Sandeep Dhavale
2023-07-11 23:38 ` Sandeep Dhavale
2023-07-12 17:02 ` Joel Fernandes
2023-07-12 17:02 ` Joel Fernandes
2023-07-12 17:02 ` Joel Fernandes
2023-07-12 21:20 ` Sandeep Dhavale via Linux-erofs
2023-07-12 21:20 ` Sandeep Dhavale
2023-07-12 21:20 ` Sandeep Dhavale
2023-07-13 0:32 ` Joel Fernandes
2023-07-13 0:32 ` Joel Fernandes
2023-07-13 0:32 ` Joel Fernandes
2023-07-13 2:02 ` Gao Xiang
2023-07-13 2:02 ` Gao Xiang
2023-07-13 2:02 ` Gao Xiang
2023-07-13 2:10 ` Gao Xiang
2023-07-13 2:10 ` Gao Xiang
2023-07-13 2:10 ` Gao Xiang
2023-07-13 2:16 ` Joel Fernandes
2023-07-13 2:16 ` Joel Fernandes
2023-07-13 2:16 ` Joel Fernandes
2023-07-13 4:27 ` Paul E. McKenney
2023-07-13 4:27 ` Paul E. McKenney
2023-07-13 4:27 ` Paul E. McKenney
2023-07-13 4:41 ` Gao Xiang
2023-07-13 4:41 ` Gao Xiang
2023-07-13 4:41 ` Gao Xiang
2023-07-13 4:52 ` Paul E. McKenney
2023-07-13 4:52 ` Paul E. McKenney
2023-07-13 4:52 ` Paul E. McKenney
2023-07-13 4:59 ` Gao Xiang
2023-07-13 4:59 ` Gao Xiang
2023-07-13 4:59 ` Gao Xiang
2023-07-13 14:07 ` Joel Fernandes
2023-07-13 14:07 ` Joel Fernandes
2023-07-13 14:07 ` Joel Fernandes
2023-07-13 14:34 ` Gao Xiang
2023-07-13 14:34 ` Gao Xiang
2023-07-13 14:34 ` Gao Xiang
2023-07-13 15:33 ` Joel Fernandes
2023-07-13 15:33 ` Joel Fernandes
2023-07-13 15:33 ` Joel Fernandes
2023-07-13 16:09 ` Alan Huang
2023-07-13 16:09 ` Alan Huang
2023-07-13 16:09 ` Alan Huang
2023-07-13 18:14 ` Paul E. McKenney
2023-07-13 18:14 ` Paul E. McKenney
2023-07-13 18:14 ` Paul E. McKenney
2023-07-13 19:00 ` Gao Xiang
2023-07-13 19:00 ` Gao Xiang
2023-07-13 19:00 ` Gao Xiang
2023-07-13 22:27 ` Paul E. McKenney
2023-07-13 22:27 ` Paul E. McKenney
2023-07-13 22:27 ` Paul E. McKenney
2023-07-13 16:33 ` Paul E. McKenney
2023-07-13 16:33 ` Paul E. McKenney
2023-07-13 16:33 ` Paul E. McKenney
2023-07-13 17:05 ` Sandeep Dhavale via Linux-erofs
2023-07-13 17:05 ` Sandeep Dhavale
2023-07-13 17:05 ` Sandeep Dhavale
2023-07-13 17:35 ` Paul E. McKenney
2023-07-13 17:35 ` Paul E. McKenney
2023-07-13 17:35 ` Paul E. McKenney
2023-07-13 18:51 ` Sandeep Dhavale via Linux-erofs
2023-07-13 18:51 ` Sandeep Dhavale
2023-07-13 18:51 ` Sandeep Dhavale
2023-07-13 22:49 ` Paul E. McKenney
2023-07-13 22:49 ` Paul E. McKenney
2023-07-13 22:49 ` Paul E. McKenney
2023-07-13 23:08 ` Sandeep Dhavale via Linux-erofs
2023-07-13 23:08 ` Sandeep Dhavale
2023-07-13 23:08 ` Sandeep Dhavale
2023-07-13 23:28 ` Paul E. McKenney
2023-07-13 23:28 ` Paul E. McKenney
2023-07-13 23:28 ` Paul E. McKenney
2023-07-14 2:16 ` Paul E. McKenney
2023-07-14 2:16 ` Paul E. McKenney
2023-07-14 2:16 ` Paul E. McKenney
2023-07-14 3:16 ` Gao Xiang
2023-07-14 3:16 ` Gao Xiang
2023-07-14 3:16 ` Gao Xiang
2023-07-14 13:42 ` Joel Fernandes
2023-07-14 13:42 ` Joel Fernandes
2023-07-14 13:42 ` Joel Fernandes
2023-07-14 13:51 ` Gao Xiang
2023-07-14 13:51 ` Gao Xiang
2023-07-14 13:51 ` Gao Xiang
2023-07-14 14:56 ` Steven Rostedt
2023-07-14 14:56 ` Steven Rostedt
2023-07-14 14:56 ` Steven Rostedt
2023-07-14 15:13 ` Paul E. McKenney
2023-07-14 15:13 ` Paul E. McKenney
2023-07-14 15:13 ` Paul E. McKenney
2023-07-14 15:35 ` Alan Huang
2023-07-14 15:35 ` Alan Huang
2023-07-14 15:35 ` Alan Huang
2023-07-14 15:54 ` Alan Huang
2023-07-14 15:54 ` Alan Huang
2023-07-14 15:54 ` Alan Huang
2023-07-14 17:02 ` Paul E. McKenney
2023-07-14 17:02 ` Paul E. McKenney
2023-07-14 17:02 ` Paul E. McKenney
2023-07-14 18:40 ` Alan Huang
2023-07-14 18:40 ` Alan Huang
2023-07-14 18:40 ` Alan Huang
2023-07-14 18:44 ` Paul E. McKenney
2023-07-14 18:44 ` Paul E. McKenney
2023-07-14 18:44 ` Paul E. McKenney
2023-07-14 19:15 ` Sandeep Dhavale via Linux-erofs
2023-07-14 19:15 ` Sandeep Dhavale
2023-07-14 19:15 ` Sandeep Dhavale
2023-07-14 19:36 ` Paul E. McKenney
2023-07-14 19:36 ` Paul E. McKenney
2023-07-14 19:36 ` Paul E. McKenney
2023-07-13 4:51 ` Gao Xiang [this message]
2023-07-13 4:51 ` Gao Xiang
2023-07-13 4:51 ` Gao Xiang
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