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Date:   Thu, 2 Jun 2022 20:19:27 +0200
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From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Davidlohr Bueso <dave@stgolabs.net>
Cc:     linux-scsi@vger.kernel.org, martin.petersen@oracle.com,
        ejb@linux.ibm.com, tglx@linutronix.de,
        Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Subject: Re: [PATCH 05/10] scsi/isci: Replace completion_tasklet with
 threaded irq
Message-ID: <Ypj/L3ySOSWqQUNu@linutronix.de>
References: <20220530231512.9729-1-dave@stgolabs.net>
 <20220530231512.9729-6-dave@stgolabs.net>
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On 2022-05-30 16:15:07 [-0700], Davidlohr Bueso wrote:
> Tasklets have long been deprecated as being too heavy on the system
> by running in irq context - and this is not a performance critical
> path. If a higher priority process wants to run, it must wait for
> the tasklet to finish before doing so. A more suitable equivalent
> is to converted to threaded irq instead and run in regular task
> context.

The convert looks okay. This driver even disables the interrupt source
before scheduling the tasklet :) However the whole routine
(sci_controller_completion_handler()) runs with disabled interrupt so it
makes no sense to use tasklets for completion or threaded interrupts=E2=80=
=A6

> Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>

Sebastian