1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Hypervisor Maintenance Interrupt (HMI) handling.
5 * Copyright 2015 IBM Corporation
6 * Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
11 #include <linux/types.h>
12 #include <linux/compiler.h>
15 #include <asm/processor.h>
17 void wait_for_subcore_guest_exit(void)
22 * NULL bitmap pointer indicates that KVM module hasn't
23 * been loaded yet and hence no guests are running, or running
24 * on POWER9 or newer CPU.
26 * If no KVM is in use, no need to co-ordinate among threads
27 * as all of them will always be in host and no one is going
28 * to modify TB other than the opal hmi handler.
30 * POWER9 and newer don't need this synchronisation.
32 * Hence, just return from here.
34 if (!local_paca->sibling_subcore_state)
37 for (i = 0; i < MAX_SUBCORE_PER_CORE; i++)
38 while (local_paca->sibling_subcore_state->in_guest[i])
42 void wait_for_tb_resync(void)
44 if (!local_paca->sibling_subcore_state)
47 while (test_bit(CORE_TB_RESYNC_REQ_BIT,
48 &local_paca->sibling_subcore_state->flags))