LXR linux/arch/powerpc/kvm/book3s_hv

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Hypervisor Maintenance Interrupt (HMI) handling.
   4 *
   5 * Copyright 2015 IBM Corporation
   6 * Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
   7 */
   8
   9#undef DEBUG
  10
  11#include <linux/types.h>
  12#include <linux/compiler.h>
  13#include <asm/paca.h>
  14#include <asm/hmi.h>
  15#include <asm/processor.h>
  16
  17void wait_for_subcore_guest_exit(void)
  18{
  19        int i;
  20
  21        /*
  22         * NULL bitmap pointer indicates that KVM module hasn't
  23         * been loaded yet and hence no guests are running.
  24         * If no KVM is in use, no need to co-ordinate among threads
  25         * as all of them will always be in host and no one is going
  26         * to modify TB other than the opal hmi handler.
  27         * Hence, just return from here.
  28         */
  29        if (!local_paca->sibling_subcore_state)
  30                return;
  31
  32        for (i = 0; i < MAX_SUBCORE_PER_CORE; i++)
  33                while (local_paca->sibling_subcore_state->in_guest[i])
  34                        cpu_relax();
  35}
  36
  37void wait_for_tb_resync(void)
  38{
  39        if (!local_paca->sibling_subcore_state)
  40                return;
  41
  42        while (test_bit(CORE_TB_RESYNC_REQ_BIT,
  43                                &local_paca->sibling_subcore_state->flags))
  44                cpu_relax();
  45}
  46