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Re: [PATCH] tracing: Have the trace_event benchmark thread call cond_resched_rcu_qs()

From Steven Rostedt <rostedt@goodmis.org>
Newsgroups linux.kernel
Subject Re: [PATCH] tracing: Have the trace_event benchmark thread call cond_resched_rcu_qs()
Date 2017-04-12 01:00 +0200
Message-ID <tvcVs-4Kn-11@gated-at.bofh.it> (permalink)
References <tvcVs-4Kn-3@gated-at.bofh.it>
Organization linux.* mail to news gateway

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On Tue, 11 Apr 2017 18:54:35 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
> 
> The trace_event benchmark thread runs in kernel space in an infinite loop
> while also calling cond_resched() in case anything else wants to schedule
> in. Unfortunately, on a PREEMPT kernel, that makes it a nop, in which case,
> this will never voluntarily schedule. That will cause synchronize_rcu_tasks()
> to forever block on this thread, while it is running.
> 
> This is exactly what cond_resched_rcu_qs() is for. Use that instead.
> 
> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>

This actually should be:

Recommended-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>

-- Steve

> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
> ---

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Thread

[PATCH] tracing: Have the trace_event benchmark thread call  cond_resched_rcu_qs() Steven Rostedt <rostedt@goodmis.org> - 2017-04-12 01:00 +0200
  Re: [PATCH] tracing: Have the trace_event benchmark thread call  cond_resched_rcu_qs() Steven Rostedt <rostedt@goodmis.org> - 2017-04-12 01:00 +0200
    Re: [PATCH] tracing: Have the trace_event benchmark thread call  cond_resched_rcu_qs() "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2017-04-12 01:50 +0200

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