Re: [PATCH v2 00/19] scsi: libsas: Remove in_interrupt() check

From: John Garry <john.garry@huawei.com>
To: "Ahmed S. Darwish" <a.darwish@linutronix.de>,
	"James E.J. Bottomley" <jejb@linux.ibm.com>,
	"Martin K. Petersen" <martin.petersen@oracle.com>,
	Jason Yan <yanaijie@huawei.com>, Daniel Wagner <dwagner@suse.de>,
	"Artur Paszkiewicz" <artur.paszkiewicz@intel.com>,
	Jack Wang <jinpu.wang@cloud.ionos.com>
Cc: <linux-scsi@vger.kernel.org>, <intel-linux-scu@intel.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	"Sebastian A. Siewior" <bigeasy@linutronix.de>
Subject: Re: [PATCH v2 00/19] scsi: libsas: Remove in_interrupt() check
Date: Tue, 12 Jan 2021 11:53:50 +0000	[thread overview]
Message-ID: <8683f401-29b6-4067-af51-7b518ad3a10f@huawei.com> (raw)
In-Reply-To: <20210112110647.627783-1-a.darwish@linutronix.de>

On 12/01/2021 11:06, Ahmed S. Darwish wrote:
> Hi,
> 
> Changelog v2
> ------------
> 
> - Rebase on top of v5.11-rc3
> 
> - Rebase on top of John's patch "scsi: libsas and users: Remove notifier
>    indirection", as it affects every other patch. Include it in this
>    series (patch #2).
> 
> - Introduce patches #13 => #19, which modify call sites back to use the
>    original libsas notifier function names without _gfp() suffix.
> 
> - Collect r-b tags
> 
> v1 Submission
> -------------
> 
>    https://lkml.kernel.org/r/20201218204354.586951-1-a.darwish@linutronix.de
> 
> Cover letter
> ------------
> 
> In the discussion about preempt count consistency across kernel
> configurations:
> 
>    https://lkml.kernel.org/r/20200914204209.256266093@linutronix.de
> 
> it was concluded that the usage of in_interrupt() and related context
> checks should be removed from non-core code.
> 
> This includes memory allocation mode decisions (GFP_*). In the long run,
> usage of in_interrupt() and its siblings should be banned from driver
> code completely.
> 
> This series addresses SCSI libsas. Basically, the function:
> 
>    => drivers/scsi/libsas/sas_init.c:
>    struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy)
>    {
>          ...
>          gfp_t flags = in_interrupt() ? GFP_ATOMIC : GFP_KERNEL;
>          event = kmem_cache_zalloc(sas_event_cache, flags);
>          ...
>    }
> 
> is transformed so that callers explicitly pass the gfp_t memory
> allocation flags. Affected libsas clients are modified accordingly.
> 
> Patches #1, #2 => #7 have "Fixes: " tags and address bugs the were
> noticed during the context analysis.
> 
> Thanks!
> 
> 8<--------------
> 
> Ahmed S. Darwish (18):
>    Documentation: scsi: libsas: Remove notify_ha_event()
>    scsi: libsas: Introduce a _gfp() variant of event notifiers
>    scsi: mvsas: Pass gfp_t flags to libsas event notifiers
>    scsi: isci: port: link down: Pass gfp_t flags
>    scsi: isci: port: link up: Pass gfp_t flags
>    scsi: isci: port: broadcast change: Pass gfp_t flags
>    scsi: libsas: Pass gfp_t flags to event notifiers
>    scsi: pm80xx: Pass gfp_t flags to libsas event notifiers
>    scsi: aic94xx: Pass gfp_t flags to libsas event notifiers
>    scsi: hisi_sas: Pass gfp_t flags to libsas event notifiers
>    scsi: libsas: event notifiers API: Add gfp_t flags parameter
>    scsi: hisi_sas: Switch back to original libsas event notifiers
>    scsi: aic94xx: Switch back to original libsas event notifiers
>    scsi: pm80xx: Switch back to original libsas event notifiers
>    scsi: libsas: Switch back to original event notifiers API
>    scsi: isci: Switch back to original libsas event notifiers
>    scsi: mvsas: Switch back to original libsas event notifiers
>    scsi: libsas: Remove temporarily-added _gfp() API variants

I'll give this a spin today and help review also then.

There's 18 patches here - it would be very convenient if they were on a 
public branch :)

Cheers,
John

> 
> John Garry (1):
>    scsi: libsas and users: Remove notifier indirection
> 
>   Documentation/scsi/libsas.rst          |  5 ++--
>   drivers/scsi/aic94xx/aic94xx_scb.c     | 20 ++++++-------
>   drivers/scsi/hisi_sas/hisi_sas.h       |  3 +-
>   drivers/scsi/hisi_sas/hisi_sas_main.c  | 29 +++++++++----------
>   drivers/scsi/hisi_sas/hisi_sas_v1_hw.c |  6 ++--
>   drivers/scsi/hisi_sas/hisi_sas_v2_hw.c |  6 ++--
>   drivers/scsi/hisi_sas/hisi_sas_v3_hw.c |  6 ++--
>   drivers/scsi/isci/port.c               | 11 +++----
>   drivers/scsi/libsas/sas_event.c        | 27 ++++++++---------
>   drivers/scsi/libsas/sas_init.c         | 17 ++++-------
>   drivers/scsi/libsas/sas_internal.h     |  5 ++--
>   drivers/scsi/mvsas/mv_sas.c            | 24 +++++++---------
>   drivers/scsi/pm8001/pm8001_hwi.c       | 40 ++++++++++++--------------
>   drivers/scsi/pm8001/pm8001_sas.c       | 12 +++-----
>   drivers/scsi/pm8001/pm80xx_hwi.c       | 37 +++++++++++-------------
>   include/scsi/libsas.h                  |  9 +++---
>   16 files changed, 115 insertions(+), 142 deletions(-)
> 
> base-commit: 7c53f6b671f4aba70ff15e1b05148b10d58c2837
> --
> 2.30.0
> .
> 