| Message ID | 1524149293-12658-3-git-send-email-pmorel@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 24/04/2018 09:25, Dong Jia Shi wrote: > * Pierre Morel <pmorel@linux.vnet.ibm.com> [2018-04-19 16:48:05 +0200]: > >> We change the FSM functions to return the next state, >> and adapt the fsm_func_t function type. > I think I'd need to read the rest patches to understand why we need this > one, but no hurt to write some ideas that I noticed at my first glance. > See below please. > >> Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com> >> --- >> drivers/s390/cio/vfio_ccw_fsm.c | 24 ++++++++++++++++-------- >> drivers/s390/cio/vfio_ccw_private.h | 5 +++-- >> 2 files changed, 19 insertions(+), 10 deletions(-) >> >> diff --git a/drivers/s390/cio/vfio_ccw_fsm.c b/drivers/s390/cio/vfio_ccw_fsm.c >> index af88551..2f3108d 100644 >> --- a/drivers/s390/cio/vfio_ccw_fsm.c >> +++ b/drivers/s390/cio/vfio_ccw_fsm.c >> @@ -60,7 +60,7 @@ static int fsm_io_helper(struct vfio_ccw_private *private) >> } >> } >> >> -static void fsm_notoper(struct vfio_ccw_private *private, >> +static int fsm_notoper(struct vfio_ccw_private *private, >> enum vfio_ccw_event event) >> { >> struct subchannel *sch = private->sch; >> @@ -71,30 +71,34 @@ static void fsm_notoper(struct vfio_ccw_private *private, >> */ >> css_sched_sch_todo(sch, SCH_TODO_UNREG); >> private->state = VFIO_CCW_STATE_NOT_OPER; > Here.. > >> + return private->state; >> } >> >> /* >> * No operation action. >> */ >> -static void fsm_nop(struct vfio_ccw_private *private, >> +static int fsm_nop(struct vfio_ccw_private *private, >> enum vfio_ccw_event event) >> { >> + return private->state; >> } >> >> -static void fsm_io_error(struct vfio_ccw_private *private, >> +static int fsm_io_error(struct vfio_ccw_private *private, >> enum vfio_ccw_event event) >> { >> pr_err("vfio-ccw: FSM: I/O request from state:%d\n", private->state); >> private->io_region.ret_code = -EIO; >> + return private->state; >> } >> >> -static void fsm_io_busy(struct vfio_ccw_private *private, >> +static int fsm_io_busy(struct vfio_ccw_private *private, >> enum vfio_ccw_event event) >> { >> private->io_region.ret_code = -EBUSY; >> + return private->state; >> } >> >> -static void fsm_disabled_irq(struct vfio_ccw_private *private, >> +static int fsm_disabled_irq(struct vfio_ccw_private *private, >> enum vfio_ccw_event event) >> { >> struct subchannel *sch = private->sch; >> @@ -104,12 +108,13 @@ static void fsm_disabled_irq(struct vfio_ccw_private *private, >> * successful - should not happen, but we try to disable again. >> */ >> cio_disable_subchannel(sch); >> + return private->state; >> } >> >> /* >> * Deal with the ccw command request from the userspace. >> */ >> -static void fsm_io_request(struct vfio_ccw_private *private, >> +static int fsm_io_request(struct vfio_ccw_private *private, >> enum vfio_ccw_event event) >> { >> union orb *orb; >> @@ -141,7 +146,7 @@ static void fsm_io_request(struct vfio_ccw_private *private, >> cp_free(&private->cp); >> goto err_out; >> } >> - return; >> + return private->state; >> } else if (scsw->cmd.fctl & SCSW_FCTL_HALT_FUNC) { >> /* XXX: Handle halt. */ >> io_region->ret_code = -EOPNOTSUPP; >> @@ -154,12 +159,13 @@ static void fsm_io_request(struct vfio_ccw_private *private, >> >> err_out: >> private->state = VFIO_CCW_STATE_IDLE; > Here.. > >> + return private->state; >> } >> >> /* >> * Got an interrupt for a normal io (state busy). >> */ >> -static void fsm_irq(struct vfio_ccw_private *private, >> +static int fsm_irq(struct vfio_ccw_private *private, >> enum vfio_ccw_event event) >> { >> struct irb *irb = &private->irb; >> @@ -172,6 +178,8 @@ static void fsm_irq(struct vfio_ccw_private *private, >> >> if (private->io_trigger) >> eventfd_signal(private->io_trigger, 1); >> + >> + return private->state; >> } >> >> /* >> diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h >> index 78a66d9..f526b18 100644 >> --- a/drivers/s390/cio/vfio_ccw_private.h >> +++ b/drivers/s390/cio/vfio_ccw_private.h >> @@ -83,13 +83,14 @@ enum vfio_ccw_event { >> /* >> * Action called through jumptable. >> */ >> -typedef void (fsm_func_t)(struct vfio_ccw_private *, enum vfio_ccw_event); >> +typedef int (fsm_func_t)(struct vfio_ccw_private *, enum vfio_ccw_event); >> extern fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS]; >> >> static inline void vfio_ccw_fsm_event(struct vfio_ccw_private *private, >> int event) >> { >> - vfio_ccw_jumptable[private->state][event](private, event); >> + private->state = vfio_ccw_jumptable[private->state][event](private, >> + event); > Since here it assigns new value to private->state, there is no need to > do that inside each fsm_func? Absolutely. I just kept the previous code, just adding the return private->state in the functions in this patch. merging the state and the return value is done in a later patch. If you prefer I can do it in this patch. > >> } >> >> extern struct workqueue_struct *vfio_ccw_work_q; >> -- >> 2.7.4 >>
On Tue, 24 Apr 2018 10:22:15 +0200 Pierre Morel <pmorel@linux.vnet.ibm.com> wrote: > On 24/04/2018 09:25, Dong Jia Shi wrote: > > * Pierre Morel <pmorel@linux.vnet.ibm.com> [2018-04-19 16:48:05 +0200]: > > > >> We change the FSM functions to return the next state, > >> and adapt the fsm_func_t function type. > > I think I'd need to read the rest patches to understand why we need this > > one, but no hurt to write some ideas that I noticed at my first glance. > > See below please. > > > >> Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com> > >> --- > >> drivers/s390/cio/vfio_ccw_fsm.c | 24 ++++++++++++++++-------- > >> drivers/s390/cio/vfio_ccw_private.h | 5 +++-- > >> 2 files changed, 19 insertions(+), 10 deletions(-) > >> diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h > >> index 78a66d9..f526b18 100644 > >> --- a/drivers/s390/cio/vfio_ccw_private.h > >> +++ b/drivers/s390/cio/vfio_ccw_private.h > >> @@ -83,13 +83,14 @@ enum vfio_ccw_event { > >> /* > >> * Action called through jumptable. > >> */ > >> -typedef void (fsm_func_t)(struct vfio_ccw_private *, enum vfio_ccw_event); > >> +typedef int (fsm_func_t)(struct vfio_ccw_private *, enum vfio_ccw_event); > >> extern fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS]; > >> > >> static inline void vfio_ccw_fsm_event(struct vfio_ccw_private *private, > >> int event) > >> { > >> - vfio_ccw_jumptable[private->state][event](private, event); > >> + private->state = vfio_ccw_jumptable[private->state][event](private, > >> + event); > > Since here it assigns new value to private->state, there is no need to > > do that inside each fsm_func? > Absolutely. > I just kept the previous code, just adding the return private->state in > the functions > in this patch. > merging the state and the return value is done in a later patch. > If you prefer I can do it in this patch. I think we should revisit this later. It's hard to judge this patch on its own.
diff --git a/drivers/s390/cio/vfio_ccw_fsm.c b/drivers/s390/cio/vfio_ccw_fsm.c index af88551..2f3108d 100644 --- a/drivers/s390/cio/vfio_ccw_fsm.c +++ b/drivers/s390/cio/vfio_ccw_fsm.c @@ -60,7 +60,7 @@ static int fsm_io_helper(struct vfio_ccw_private *private) } } -static void fsm_notoper(struct vfio_ccw_private *private, +static int fsm_notoper(struct vfio_ccw_private *private, enum vfio_ccw_event event) { struct subchannel *sch = private->sch; @@ -71,30 +71,34 @@ static void fsm_notoper(struct vfio_ccw_private *private, */ css_sched_sch_todo(sch, SCH_TODO_UNREG); private->state = VFIO_CCW_STATE_NOT_OPER; + return private->state; } /* * No operation action. */ -static void fsm_nop(struct vfio_ccw_private *private, +static int fsm_nop(struct vfio_ccw_private *private, enum vfio_ccw_event event) { + return private->state; } -static void fsm_io_error(struct vfio_ccw_private *private, +static int fsm_io_error(struct vfio_ccw_private *private, enum vfio_ccw_event event) { pr_err("vfio-ccw: FSM: I/O request from state:%d\n", private->state); private->io_region.ret_code = -EIO; + return private->state; } -static void fsm_io_busy(struct vfio_ccw_private *private, +static int fsm_io_busy(struct vfio_ccw_private *private, enum vfio_ccw_event event) { private->io_region.ret_code = -EBUSY; + return private->state; } -static void fsm_disabled_irq(struct vfio_ccw_private *private, +static int fsm_disabled_irq(struct vfio_ccw_private *private, enum vfio_ccw_event event) { struct subchannel *sch = private->sch; @@ -104,12 +108,13 @@ static void fsm_disabled_irq(struct vfio_ccw_private *private, * successful - should not happen, but we try to disable again. */ cio_disable_subchannel(sch); + return private->state; } /* * Deal with the ccw command request from the userspace. */ -static void fsm_io_request(struct vfio_ccw_private *private, +static int fsm_io_request(struct vfio_ccw_private *private, enum vfio_ccw_event event) { union orb *orb; @@ -141,7 +146,7 @@ static void fsm_io_request(struct vfio_ccw_private *private, cp_free(&private->cp); goto err_out; } - return; + return private->state; } else if (scsw->cmd.fctl & SCSW_FCTL_HALT_FUNC) { /* XXX: Handle halt. */ io_region->ret_code = -EOPNOTSUPP; @@ -154,12 +159,13 @@ static void fsm_io_request(struct vfio_ccw_private *private, err_out: private->state = VFIO_CCW_STATE_IDLE; + return private->state; } /* * Got an interrupt for a normal io (state busy). */ -static void fsm_irq(struct vfio_ccw_private *private, +static int fsm_irq(struct vfio_ccw_private *private, enum vfio_ccw_event event) { struct irb *irb = &private->irb; @@ -172,6 +178,8 @@ static void fsm_irq(struct vfio_ccw_private *private, if (private->io_trigger) eventfd_signal(private->io_trigger, 1); + + return private->state; } /* diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h index 78a66d9..f526b18 100644 --- a/drivers/s390/cio/vfio_ccw_private.h +++ b/drivers/s390/cio/vfio_ccw_private.h @@ -83,13 +83,14 @@ enum vfio_ccw_event { /* * Action called through jumptable. */ -typedef void (fsm_func_t)(struct vfio_ccw_private *, enum vfio_ccw_event); +typedef int (fsm_func_t)(struct vfio_ccw_private *, enum vfio_ccw_event); extern fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS]; static inline void vfio_ccw_fsm_event(struct vfio_ccw_private *private, int event) { - vfio_ccw_jumptable[private->state][event](private, event); + private->state = vfio_ccw_jumptable[private->state][event](private, + event); } extern struct workqueue_struct *vfio_ccw_work_q;
We change the FSM functions to return the next state, and adapt the fsm_func_t function type. Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com> --- drivers/s390/cio/vfio_ccw_fsm.c | 24 ++++++++++++++++-------- drivers/s390/cio/vfio_ccw_private.h | 5 +++-- 2 files changed, 19 insertions(+), 10 deletions(-)