Re: [PATCH 09/14] scsi: mpt3sas: Remove in_interrupt().

Daniel Wagner
2020-11-30T15:17:33Z

On Thu, Nov 26, 2020 at 02:29:47PM +0100, Sebastian Andrzej Siewior wrote:
> From: "Ahmed S. Darwish" <a.darwish@linutronix.de>
>
> _scsih_fw_event_cleanup_queue() waits for all outstanding firmware
> events wokrqueue handlers to finish. If in_interrupt() is true, it
> cancels itself and return early.
>
> That in_interrupt() check is ill-defined and does not provide what the
> name suggests: it does not cover all states in which it is safe to block
> and call functions like cancel_work_sync().
>
> That check is also not needed: _scsih_fw_event_cleanup_queue() is always
> invoked from process context. Below is an analysis of its callers:
>
> - scsih_remove(), bound to PCI ->remove(), process context
>
> - scsih_shutdown(), bound to PCI ->shutdown(), process context
>
> - mpt3sas_scsih_clear_outstanding_scsi_tm_commands(), called by
> => _base_clear_outstanding_commands(), called by
> =>_base_fault_reset_work(), workqueue
> => mpt3sas_base_hard_reset_handler(), locks mutex
>
> Remove the in_interrupt() check. Change _scsih_fw_event_cleanup_queue()
> specification to a purely process-context function and mark it with
> "Context: task, can sleep".
>
> Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> Cc: Sathya Prakash <sathya.prakash@broadcom.com>
> Cc: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
> Cc: Suganath Prabu Subramani <suganath-prabu.subramani@broadcom.com>
> Cc: <MPT-FusionLinux.pdl@broadcom.com>

Reviewed-by: Daniel Wagner <dwagner@suse.de>