Re: [PATCH 7/9] s390: Convert from tasklet to BH workqueue

From: Alexandra Winter <wintera@linux.ibm.com>
To: Allen Pais <apais@linux.microsoft.com>, linux-kernel@vger.kernel.org
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Subject: Re: [PATCH 7/9] s390: Convert from tasklet to BH workqueue
Date: Tue, 2 Apr 2024 14:48:14 +0200	[thread overview]
Message-ID: <ea4ac7a3-13ae-4d22-a3d9-fcb7d9e8d751@linux.ibm.com> (raw)
In-Reply-To: <20240327160314.9982-8-apais@linux.microsoft.com>

On 27.03.24 17:03, Allen Pais wrote:
> The only generic interface to execute asynchronously in the BH context is
> tasklet; however, it's marked deprecated and has some design flaws. To
> replace tasklets, BH workqueue support was recently added. A BH workqueue
> behaves similarly to regular workqueues except that the queued work items
> are executed in the BH context.
> 
> This patch converts drivers/infiniband/* from tasklet to BH workqueue.
> 
> Based on the work done by Tejun Heo <tj@kernel.org>
> Branch: https://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git for-6.10
> 
> Note: Not tested. Please test/review.
> 
> Signed-off-by: Allen Pais <allen.lkml@gmail.com>
> ---
>  drivers/s390/block/dasd.c              | 42 ++++++++++++------------
>  drivers/s390/block/dasd_int.h          | 10 +++---
>  drivers/s390/char/con3270.c            | 27 ++++++++--------
>  drivers/s390/crypto/ap_bus.c           | 24 +++++++-------
>  drivers/s390/crypto/ap_bus.h           |  2 +-
>  drivers/s390/crypto/zcrypt_msgtype50.c |  2 +-
>  drivers/s390/crypto/zcrypt_msgtype6.c  |  4 +--
>  drivers/s390/net/ctcm_fsms.c           |  4 +--
>  drivers/s390/net/ctcm_main.c           | 15 ++++-----
>  drivers/s390/net/ctcm_main.h           |  5 +--
>  drivers/s390/net/ctcm_mpc.c            | 12 +++----
>  drivers/s390/net/ctcm_mpc.h            |  7 ++--
>  drivers/s390/net/lcs.c                 | 26 +++++++--------
>  drivers/s390/net/lcs.h                 |  2 +-
>  drivers/s390/net/qeth_core_main.c      |  2 +-
>  drivers/s390/scsi/zfcp_qdio.c          | 45 +++++++++++++-------------
>  drivers/s390/scsi/zfcp_qdio.h          |  9 +++---
>  17 files changed, 117 insertions(+), 121 deletions(-)
> 

We're looking into the best way to test this. 

For drivers/s390/net/ctcm* and drivers/s390/net/lcs*:
Acked-by: Alexandra Winter <wintera@linux.ibm.com>

[...]
> diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
> index a0cce6872075..10ea95abc753 100644
> --- a/drivers/s390/net/qeth_core_main.c
> +++ b/drivers/s390/net/qeth_core_main.c
> @@ -2911,7 +2911,7 @@ static int qeth_init_input_buffer(struct qeth_card *card,
>  	}
>  
>  	/*
> -	 * since the buffer is accessed only from the input_tasklet
> +	 * since the buffer is accessed only from the input_work
>  	 * there shouldn't be a need to synchronize; also, since we use
>  	 * the QETH_IN_BUF_REQUEUE_THRESHOLD we should never run  out off
>  	 * buffers

I propose to delete the whole comment block. There have been many changes and 
I don't think it is helpful for the current qeth driver.