[v3] s390x: TOD refactoring + TCG CPU hotplug support

[Qemu-devel] [PATCH v3 6/9] s390x/tcg: SET CLOCK COMPARATOR can clear CKC interrupts

Posted by David Hildenbrand 7 years, 4 months ago

Let's stop the timer and delete any pending CKC IRQ before doing
anything else.

While at it, add a comment while the check for ckc == -1ULL is needed.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
 target/s390x/misc_helper.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/target/s390x/misc_helper.c b/target/s390x/misc_helper.c
index be341b5295..4872bdd774 100644
--- a/target/s390x/misc_helper.c
+++ b/target/s390x/misc_helper.c
@@ -156,6 +156,13 @@ void HELPER(sckc)(CPUS390XState *env, uint64_t time)
     S390TODClass *tdc = S390_TOD_GET_CLASS(td);
     S390TOD tod_base;
 
+    /* stop the timer and remove pending CKC IRQs */
+    timer_del(env->tod_timer);
+    qemu_mutex_lock_iothread();
+    env->pending_int &= ~INTERRUPT_EXT_CLOCK_COMPARATOR;
+    qemu_mutex_unlock_iothread();
+
+    /* the tod has to exceed the ckc, this can never happen if ckc is all 1's */
     if (time == -1ULL) {
         return;
     }
-- 
2.17.1

Re: [Qemu-devel] [PATCH v3 6/9] s390x/tcg: SET CLOCK COMPARATOR can clear CKC interrupts

Posted by Cornelia Huck 7 years, 4 months ago

On Mon, 25 Jun 2018 13:53:49 +0200
David Hildenbrand <david@redhat.com> wrote:

> Let's stop the timer and delete any pending CKC IRQ before doing
> anything else.
> 
> While at it, add a comment while the check for ckc == -1ULL is needed.

s/while/why/

> 
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  target/s390x/misc_helper.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/target/s390x/misc_helper.c b/target/s390x/misc_helper.c
> index be341b5295..4872bdd774 100644
> --- a/target/s390x/misc_helper.c
> +++ b/target/s390x/misc_helper.c
> @@ -156,6 +156,13 @@ void HELPER(sckc)(CPUS390XState *env, uint64_t time)
>      S390TODClass *tdc = S390_TOD_GET_CLASS(td);
>      S390TOD tod_base;
>  
> +    /* stop the timer and remove pending CKC IRQs */
> +    timer_del(env->tod_timer);
> +    qemu_mutex_lock_iothread();
> +    env->pending_int &= ~INTERRUPT_EXT_CLOCK_COMPARATOR;
> +    qemu_mutex_unlock_iothread();
> +
> +    /* the tod has to exceed the ckc, this can never happen if ckc is all 1's */
>      if (time == -1ULL) {
>          return;
>      }

Re: [Qemu-devel] [qemu-s390x] [PATCH v3 6/9] s390x/tcg: SET CLOCK COMPARATOR can clear CKC interrupts

Posted by Thomas Huth 7 years, 4 months ago

On 25.06.2018 13:53, David Hildenbrand wrote:
> Let's stop the timer and delete any pending CKC IRQ before doing
> anything else.
> 
> While at it, add a comment while the check for ckc == -1ULL is needed.
> 
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  target/s390x/misc_helper.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/target/s390x/misc_helper.c b/target/s390x/misc_helper.c
> index be341b5295..4872bdd774 100644
> --- a/target/s390x/misc_helper.c
> +++ b/target/s390x/misc_helper.c
> @@ -156,6 +156,13 @@ void HELPER(sckc)(CPUS390XState *env, uint64_t time)
>      S390TODClass *tdc = S390_TOD_GET_CLASS(td);
>      S390TOD tod_base;
>  
> +    /* stop the timer and remove pending CKC IRQs */
> +    timer_del(env->tod_timer);
> +    qemu_mutex_lock_iothread();
> +    env->pending_int &= ~INTERRUPT_EXT_CLOCK_COMPARATOR;
> +    qemu_mutex_unlock_iothread();
> +
> +    /* the tod has to exceed the ckc, this can never happen if ckc is all 1's */
>      if (time == -1ULL) {
>          return;
>      }
> 

With the commit message ("while" -> "why") fixed:

Reviewed-by: Thomas Huth <thuth@redhat.com>