On 12/10/2021 17.31, Eric Farman wrote:
On Tue, 2021-10-12 at 17:23 +0200, Thomas Huth wrote:
On 11/10/2021 09.45, Christian Borntraeger wrote:
Am 08.10.21 um 22:31 schrieb Eric Farman:
Now that we check for the STOP IRQ injection at the top of the
SIGP
handler (before the userspace/kernelspace check), we don't need
to do
it down here for the Restart order.
Signed-off-by: Eric Farman <farman@xxxxxxxxxxxxx>
---
arch/s390/kvm/sigp.c | 11 +----------
1 file changed, 1 insertion(+), 10 deletions(-)
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index 6ca01bbc72cf..0c08927ca7c9 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -240,17 +240,8 @@ static int __sigp_sense_running(struct
kvm_vcpu *vcpu,
static int __prepare_sigp_re_start(struct kvm_vcpu *vcpu,
struct kvm_vcpu *dst_vcpu, u8 order_code)
{
- struct kvm_s390_local_interrupt *li = &dst_vcpu-
arch.local_int;
/* handle (RE)START in user space */
- int rc = -EOPNOTSUPP;
-
- /* make sure we don't race with STOP irq injection */
- spin_lock(&li->lock);
- if (kvm_s390_is_stop_irq_pending(dst_vcpu))
- rc = SIGP_CC_BUSY;
- spin_unlock(&li->lock);
-
- return rc;
+ return -EOPNOTSUPP;
}
static int __prepare_sigp_cpu_reset(struct kvm_vcpu *vcpu,
@thuth?
Question is, does it make sense to merge patch 2 and 3 to make
things more
obvious?
Maybe.
Anyway: Would it make sense to remove __prepare_sigp_re_start()
completely
now and let __prepare_sigp_unknown() set the return code in the
"default:" case?
We could, but that would affect the SIGP START case which also uses the
re_start routine. And if we're going down that path, we could remove
(INITIAL) CPU RESET handled in __prepare_sigp_cpu_reset, which does the
same thing (nothing). Not sure it buys us much, other than losing the
details in the different counters of which SIGP orders are processed.
Ok, we likely shouldn't change the way of counting the SIGPs here...
So what about removing the almost empty function and simply do the "rc =
-EOPNOTSUPP" right in the handle_sigp_dst() function? That's still the
easiest way to read the code, I think. And we should do the same with the
__prepare_sigp_cpu_reset() function (in a separate patch). Just my 0.02 € of
course.
Thomas
