linux/arch/powerpc/kernel/hmi.c

57 lines
1.6 KiB
C

/*
* 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();
}