| Message ID | 20200330084911.34248-2-borntraeger@de.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | s390x/smp fix and enhancement | expand |
On 30.03.20 10:49, Christian Borntraeger wrote: > On s390x hosts with a single CPU, the smp test case hangs (loops). > The check is our restart has finished is wrong. > Sigp sense running status checks if the CPU is currently backed by a > real CPU. This means that on single CPU hosts a sigp sense running > will never claim that a target is running. We need to check for not > being stopped instead. > > Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> > --- > lib/s390x/smp.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/lib/s390x/smp.c b/lib/s390x/smp.c > index 2555bf4..5ed8b7b 100644 > --- a/lib/s390x/smp.c > +++ b/lib/s390x/smp.c > @@ -128,7 +128,7 @@ static int smp_cpu_restart_nolock(uint16_t addr, struct psw *psw) > * The order has been accepted, but the actual restart may not > * have been performed yet, so wait until the cpu is running. > */ > - while (!smp_cpu_running(addr)) > + while (smp_cpu_stopped(addr)) > mb(); > cpu->active = true; > return 0; > Reviewed-by: David Hildenbrand <david@redhat.com>
On 3/30/20 10:49 AM, Christian Borntraeger wrote: > On s390x hosts with a single CPU, the smp test case hangs (loops). > The check is our restart has finished is wrong. > Sigp sense running status checks if the CPU is currently backed by a > real CPU. This means that on single CPU hosts a sigp sense running > will never claim that a target is running. We need to check for not > being stopped instead. > > Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com> > --- > lib/s390x/smp.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/lib/s390x/smp.c b/lib/s390x/smp.c > index 2555bf4..5ed8b7b 100644 > --- a/lib/s390x/smp.c > +++ b/lib/s390x/smp.c > @@ -128,7 +128,7 @@ static int smp_cpu_restart_nolock(uint16_t addr, struct psw *psw) > * The order has been accepted, but the actual restart may not > * have been performed yet, so wait until the cpu is running. > */ > - while (!smp_cpu_running(addr)) > + while (smp_cpu_stopped(addr)) > mb(); > cpu->active = true; > return 0; >
On Mon, 30 Mar 2020 04:49:10 -0400 Christian Borntraeger <borntraeger@de.ibm.com> wrote: > On s390x hosts with a single CPU, the smp test case hangs (loops). > The check is our restart has finished is wrong. s/is/if/ > Sigp sense running status checks if the CPU is currently backed by a > real CPU. This means that on single CPU hosts a sigp sense running > will never claim that a target is running. We need to check for not > being stopped instead. > > Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> > --- > lib/s390x/smp.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/lib/s390x/smp.c b/lib/s390x/smp.c > index 2555bf4..5ed8b7b 100644 > --- a/lib/s390x/smp.c > +++ b/lib/s390x/smp.c > @@ -128,7 +128,7 @@ static int smp_cpu_restart_nolock(uint16_t addr, struct psw *psw) > * The order has been accepted, but the actual restart may not > * have been performed yet, so wait until the cpu is running. > */ > - while (!smp_cpu_running(addr)) > + while (smp_cpu_stopped(addr)) > mb(); > cpu->active = true; > return 0; Reviewed-by: Cornelia Huck <cohuck@redhat.com>
On 31.03.20 08:49, Cornelia Huck wrote: > On Mon, 30 Mar 2020 04:49:10 -0400 > Christian Borntraeger <borntraeger@de.ibm.com> wrote: > >> On s390x hosts with a single CPU, the smp test case hangs (loops). >> The check is our restart has finished is wrong. > > s/is/if/ With that fixed up queued to https://github.com/davidhildenbrand/kvm-unit-tests.git s390x-next I'll wait with the other patch until we have a consent there regarding possible races.
diff --git a/lib/s390x/smp.c b/lib/s390x/smp.c index 2555bf4..5ed8b7b 100644 --- a/lib/s390x/smp.c +++ b/lib/s390x/smp.c @@ -128,7 +128,7 @@ static int smp_cpu_restart_nolock(uint16_t addr, struct psw *psw) * The order has been accepted, but the actual restart may not * have been performed yet, so wait until the cpu is running. */ - while (!smp_cpu_running(addr)) + while (smp_cpu_stopped(addr)) mb(); cpu->active = true; return 0;
On s390x hosts with a single CPU, the smp test case hangs (loops). The check is our restart has finished is wrong. Sigp sense running status checks if the CPU is currently backed by a real CPU. This means that on single CPU hosts a sigp sense running will never claim that a target is running. We need to check for not being stopped instead. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> --- lib/s390x/smp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)