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From:   "Zhang, Qiang1" <qiang1.zhang@intel.com>
To:     "paulmck@kernel.org" <paulmck@kernel.org>
CC:     "frederic@kernel.org" <frederic@kernel.org>,
        "rcu@vger.kernel.org" <rcu@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH v3 0/2] Add no-idle tasks check which in dyntick-idle
 state
Thread-Topic: [PATCH v3 0/2] Add no-idle tasks check which in dyntick-idle
 state
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Date:   Tue, 24 May 2022 22:28:41 +0000
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References: <20220524003454.1887414-1-qiang1.zhang@intel.com>
 <20220524172855.GP1790663@paulmck-ThinkPad-P17-Gen-1>
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On Tue, May 24, 2022 at 08:34:52AM +0800, Zqiang wrote:
> These commit stop scanning no-idle tasks which in dyntick-idle state=20
> and remove idle-tasks check from warnings.

>This patch might well be correct, but there are supposed to be upcoming ch=
anges in the idle loop that would make it possible for RCU Tasks to take id=
le tasks into account:
>
>https://lore.kernel.org/all/20220515203653.4039075-1-jolsa@kernel.org/
>
>There are currently issues in amd_e400_idle() and mwait_idle() preventing =
this, and there might well also be similar issues in non-x86 idle loops:
>
>https://lore.kernel.org/all/20220519135439.GX1790663@paulmck-ThinkPad-P17-=
Gen-1/
>
>So I must hold off on this patch series for the time being.  Nevertheless,=
 thank you very much for your effort and interest in RCU.

Thanks for explain, I will keep an eye.

>
>							Thanx, Paul

> v1->v2:
> fix build error when CONFIG_TASKS_RCU=3Dn
> v2->v3:
> remove idle-tasks check from task_is_on_dyntick_idle()
>=20
> Zqiang (2):
>   rcu-tasks: Stop RCU Tasks scanning no-idle tasks which record on
>     dyntick-idle entry
>   rcu-tasks: Remove is_idle_task() from warnings in=20
> check_holdout_task()
>=20
>  kernel/rcu/tasks.h | 16 ++++++++++------
>  1 file changed, 10 insertions(+), 6 deletions(-)
>=20
> --
> 2.25.1
>=20