diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv_hmi.c')
-rw-r--r-- | arch/powerpc/kvm/book3s_hv_hmi.c | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_hmi.c b/arch/powerpc/kvm/book3s_hv_hmi.c new file mode 100644 index 000000000..e3f738eb1 --- /dev/null +++ b/arch/powerpc/kvm/book3s_hv_hmi.c @@ -0,0 +1,56 @@ +/* + * Hypervisor Maintenance Interrupt (HMI) handling. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. + * + * Copyright 2015 IBM Corporation + * Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> + */ + +#undef DEBUG + +#include <linux/types.h> +#include <linux/compiler.h> +#include <asm/paca.h> +#include <asm/hmi.h> + +void wait_for_subcore_guest_exit(void) +{ + int i; + + /* + * NULL bitmap pointer indicates that KVM module hasn't + * been loaded yet and hence no guests are running. + * If no KVM is in use, no need to co-ordinate among threads + * as all of them will always be in host and no one is going + * to modify TB other than the opal hmi handler. + * Hence, just return from here. + */ + if (!local_paca->sibling_subcore_state) + return; + + for (i = 0; i < MAX_SUBCORE_PER_CORE; i++) + while (local_paca->sibling_subcore_state->in_guest[i]) + cpu_relax(); +} + +void wait_for_tb_resync(void) +{ + if (!local_paca->sibling_subcore_state) + return; + + while (test_bit(CORE_TB_RESYNC_REQ_BIT, + &local_paca->sibling_subcore_state->flags)) + cpu_relax(); +} |