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From:   "Zhuo, Qiuxu" <qiuxu.zhuo@intel.com>
To:     Uladzislau Rezki <urezki@gmail.com>
CC:     "Paul E . McKenney" <paulmck@kernel.org>,
        RCU <rcu@vger.kernel.org>,
        "quic_neeraju@quicinc.com" <quic_neeraju@quicinc.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        Joel Fernandes <joel@joelfernandes.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Frederic Weisbecker <frederic@kernel.org>
Subject: RE: [PATCH 1/1] Reduce synchronize_rcu() waiting time
Thread-Topic: [PATCH 1/1] Reduce synchronize_rcu() waiting time
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Date:   Wed, 22 Mar 2023 01:49:50 +0000
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Hi Rezki,

> From: Uladzislau Rezki <urezki@gmail.com>
> Sent: Tuesday, March 21, 2023 11:16 PM
> [...]
> >
> >
> > If possible, may I know the steps, commands, and related parameters to
> produce the results above?
> > Thank you!
> >
> Build the kernel with CONFIG_RCU_TRACE configuration. Update your
> "set_event"
> file with appropriate traces:
>=20
> <snip>
> XQ-DQ54:/sys/kernel/tracing # echo rcu:rcu_batch_start rcu:rcu_batch_end
> rcu:rcu_invoke_callback > set_event
>=20
> XQ-DQ54:/sys/kernel/tracing # cat set_event rcu:rcu_batch_start
> rcu:rcu_invoke_callback rcu:rcu_batch_end XQ-DQ54:/sys/kernel/tracing #
> <snip>
>=20
> Collect traces as much as you want: XQ-DQ54:/sys/kernel/tracing # echo 1 =
>
> tracing_on; sleep 10; echo 0 > tracing_on Next problem is how to parse it=
. Of

Thanks for the detailed steps to collect the related testing results.

> course you will not be able to parse megabytes of traces. For that purpos=
e i
> use a special C trace parser.
> If you need an example please let me know i can show here.
>

Yes, your example parser should save me from a huge amount of traces. ;-)
Thanks so much for your sharing.

- Qiuxu

> --
> Uladzislau Rezki