[kvm-unit-tests PATCH v5 7/7] s390x: smp: Wait for cpu setup to finish

Janosch Frank
2020-02-01T15:29:10Z

We store the user provided psw address into restart new, so a psw
restart does not lead us through setup again.

Also we wait on smp_cpu_setup() until the cpu has finished setup
before returning. This is necessary for z/VM and LPAR where sigp is
asynchronous.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
---
lib/s390x/smp.c | 3 +++
s390x/cstart64.S | 2 ++
2 files changed, 5 insertions(+)

diff --git a/lib/s390x/smp.c b/lib/s390x/smp.c
index 4578003..3f86243 100644
--- a/lib/s390x/smp.c
+++ b/lib/s390x/smp.c
@@ -210,6 +210,9 @@ int smp_cpu_setup(uint16_t addr, struct psw psw)

/* Start processing */
smp_cpu_restart_nolock(addr, NULL);
+ /* Wait until the cpu has finished setup and started the provided psw */
+ while (lc->restart_new_psw.addr != psw.addr)
+ mb();
out:
spin_unlock(&lock);
return rc;
diff --git a/s390x/cstart64.S b/s390x/cstart64.S
index 86dd4c4..9af6bb3 100644
--- a/s390x/cstart64.S
+++ b/s390x/cstart64.S
@@ -159,6 +159,8 @@ smp_cpu_setup_state:
xgr %r1, %r1
lmg %r0, %r15, GEN_LC_SW_INT_GRS
lctlg %c0, %c0, GEN_LC_SW_INT_CRS
+ /* We should only go once through cpu setup and not for every restart */
+ stg %r14, GEN_LC_RESTART_NEW_PSW + 8
br %r14

pgm_int:
--
2.20.1