Re: [PATCH] [RFC] scsi: Convert from tasklet to BH workqueue

From: Michael Ellerman
Date: Thu May 02 2024 - 22:04:00 EST


Allen Pais <apais@xxxxxxxxxxxxxxxxxxx> writes:
> 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/scsi/* from tasklet to BH workqueue.
>
> Based on the work done by Tejun Heo <tj@xxxxxxxxxx>
> Branch: https://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git for-6.10
>
> Signed-off-by: Allen Pais <allen.lkml@xxxxxxxxx>
> ---
> drivers/scsi/aic7xxx/aic7xxx_osm.c | 2 +-
> drivers/scsi/aic94xx/aic94xx_hwi.c | 14 ++--
> drivers/scsi/aic94xx/aic94xx_hwi.h | 5 +-
> drivers/scsi/aic94xx/aic94xx_scb.c | 36 +++++-----
> drivers/scsi/aic94xx/aic94xx_task.c | 14 ++--
> drivers/scsi/aic94xx/aic94xx_tmf.c | 34 ++++-----
> drivers/scsi/esas2r/esas2r.h | 12 ++--
> drivers/scsi/esas2r/esas2r_init.c | 14 ++--
> drivers/scsi/esas2r/esas2r_int.c | 18 ++---
> drivers/scsi/esas2r/esas2r_io.c | 2 +-
> drivers/scsi/esas2r/esas2r_main.c | 16 ++---
> drivers/scsi/ibmvscsi/ibmvfc.c | 16 ++---
> drivers/scsi/ibmvscsi/ibmvfc.h | 3 +-
> drivers/scsi/ibmvscsi/ibmvscsi.c | 16 ++---
> drivers/scsi/ibmvscsi/ibmvscsi.h | 3 +-
> drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c | 15 ++--
> drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.h | 3 +-

Something there is giving me a build failure (ppc64le_guest_defconfig):

+ make -s 'CC=ccache powerpc64le-linux-gnu-gcc' -j 4
/linux/drivers/scsi/ibmvscsi/ibmvscsi.c: In function 'ibmvscsi_init_crq_queue':
Error: /linux/drivers/scsi/ibmvscsi/ibmvscsi.c:370:331: error: 'ibmvscsi_work' undeclared (first use in this function)
/linux/drivers/scsi/ibmvscsi/ibmvscsi.c:370:331: note: each undeclared identifier is reported only once for each function it appears in
/linux/scripts/Makefile.build:244: recipe for target 'drivers/scsi/ibmvscsi/ibmvscsi.o' failed
/linux/scripts/Makefile.build:485: recipe for target 'drivers/scsi/ibmvscsi' failed
/linux/scripts/Makefile.build:485: recipe for target 'drivers/scsi' failed
/linux/scripts/Makefile.build:485: recipe for target 'drivers' failed
/linux/drivers/scsi/ibmvscsi/ibmvscsi.c: In function 'ibmvscsi_probe':
Error: /linux/drivers/scsi/ibmvscsi/ibmvscsi.c:2255:78: error: passing argument 1 of 'kthread_create_on_node' from incompatible pointer type [-Werror=incompatible-pointer-types]
In file included from /linux/drivers/scsi/ibmvscsi/ibmvscsi.c:56:0:
/linux/include/linux/kthread.h:11:21: note: expected 'int (*)(void *)' but argument is of type 'int (*)(struct work_struct *)'
struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
^
/linux/drivers/scsi/ibmvscsi/ibmvscsi.c: At top level:
Warning: /linux/drivers/scsi/ibmvscsi/ibmvscsi.c:212:13: warning: 'ibmvscsi_task' defined but not used [-Wunused-function]
static void ibmvscsi_task(void *data)
^
Warning: cc1: warning: unrecognized command line option '-Wno-shift-negative-value'
Warning: cc1: warning: unrecognized command line option '-Wno-stringop-overflow'
cc1: some warnings being treated as errors
make[6]: *** [drivers/scsi/ibmvscsi/ibmvscsi.o] Error 1
make[5]: *** [drivers/scsi/ibmvscsi] Error 2
make[4]: *** [drivers/scsi] Error 2
make[3]: *** [drivers] Error 2
make[3]: *** Waiting for unfinished jobs....

Full log here: https://github.com/linuxppc/linux-snowpatch/actions/runs/8930174372/job/24529645923

Cross compile instructions if you're keen: https://github.com/linuxppc/wiki/wiki/Building-powerpc-kernels

cheers