144 lines
4.6 KiB
C
144 lines
4.6 KiB
C
/*
|
|
* QEMU TCG Single Threaded vCPUs implementation using instruction counting
|
|
*
|
|
* Copyright (c) 2003-2008 Fabrice Bellard
|
|
* Copyright (c) 2014 Red Hat Inc.
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
|
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
* THE SOFTWARE.
|
|
*/
|
|
|
|
#include "qemu/osdep.h"
|
|
#include "qemu-common.h"
|
|
#include "sysemu/tcg.h"
|
|
#include "sysemu/replay.h"
|
|
#include "qemu/main-loop.h"
|
|
#include "qemu/guest-random.h"
|
|
#include "exec/exec-all.h"
|
|
|
|
#include "tcg-accel-ops.h"
|
|
#include "tcg-accel-ops-icount.h"
|
|
#include "tcg-accel-ops-rr.h"
|
|
|
|
static int64_t icount_get_limit(void)
|
|
{
|
|
int64_t deadline;
|
|
|
|
if (replay_mode != REPLAY_MODE_PLAY) {
|
|
/*
|
|
* Include all the timers, because they may need an attention.
|
|
* Too long CPU execution may create unnecessary delay in UI.
|
|
*/
|
|
deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL,
|
|
QEMU_TIMER_ATTR_ALL);
|
|
/* Check realtime timers, because they help with input processing */
|
|
deadline = qemu_soonest_timeout(deadline,
|
|
qemu_clock_deadline_ns_all(QEMU_CLOCK_REALTIME,
|
|
QEMU_TIMER_ATTR_ALL));
|
|
|
|
/*
|
|
* Maintain prior (possibly buggy) behaviour where if no deadline
|
|
* was set (as there is no QEMU_CLOCK_VIRTUAL timer) or it is more than
|
|
* INT32_MAX nanoseconds ahead, we still use INT32_MAX
|
|
* nanoseconds.
|
|
*/
|
|
if ((deadline < 0) || (deadline > INT32_MAX)) {
|
|
deadline = INT32_MAX;
|
|
}
|
|
|
|
return icount_round(deadline);
|
|
} else {
|
|
return replay_get_instructions();
|
|
}
|
|
}
|
|
|
|
static void icount_notify_aio_contexts(void)
|
|
{
|
|
/* Wake up other AioContexts. */
|
|
qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
|
|
qemu_clock_run_timers(QEMU_CLOCK_VIRTUAL);
|
|
}
|
|
|
|
void icount_handle_deadline(void)
|
|
{
|
|
assert(qemu_in_vcpu_thread());
|
|
int64_t deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL,
|
|
QEMU_TIMER_ATTR_ALL);
|
|
|
|
/*
|
|
* Instructions, interrupts, and exceptions are processed in cpu-exec.
|
|
* Don't interrupt cpu thread, when these events are waiting
|
|
* (i.e., there is no checkpoint)
|
|
*/
|
|
if (deadline == 0
|
|
&& (replay_mode != REPLAY_MODE_PLAY || replay_has_checkpoint())) {
|
|
icount_notify_aio_contexts();
|
|
}
|
|
}
|
|
|
|
void icount_prepare_for_run(CPUState *cpu)
|
|
{
|
|
int insns_left;
|
|
|
|
/*
|
|
* These should always be cleared by icount_process_data after
|
|
* each vCPU execution. However u16.high can be raised
|
|
* asynchronously by cpu_exit/cpu_interrupt/tcg_handle_interrupt
|
|
*/
|
|
g_assert(cpu_neg(cpu)->icount_decr.u16.low == 0);
|
|
g_assert(cpu->icount_extra == 0);
|
|
|
|
cpu->icount_budget = icount_get_limit();
|
|
insns_left = MIN(0xffff, cpu->icount_budget);
|
|
cpu_neg(cpu)->icount_decr.u16.low = insns_left;
|
|
cpu->icount_extra = cpu->icount_budget - insns_left;
|
|
|
|
replay_mutex_lock();
|
|
|
|
if (cpu->icount_budget == 0 && replay_has_checkpoint()) {
|
|
icount_notify_aio_contexts();
|
|
}
|
|
}
|
|
|
|
void icount_process_data(CPUState *cpu)
|
|
{
|
|
/* Account for executed instructions */
|
|
icount_update(cpu);
|
|
|
|
/* Reset the counters */
|
|
cpu_neg(cpu)->icount_decr.u16.low = 0;
|
|
cpu->icount_extra = 0;
|
|
cpu->icount_budget = 0;
|
|
|
|
replay_account_executed_instructions();
|
|
|
|
replay_mutex_unlock();
|
|
}
|
|
|
|
void icount_handle_interrupt(CPUState *cpu, int mask)
|
|
{
|
|
int old_mask = cpu->interrupt_request;
|
|
|
|
tcg_handle_interrupt(cpu, mask);
|
|
if (qemu_cpu_is_self(cpu) &&
|
|
!cpu->can_do_io
|
|
&& (mask & ~old_mask) != 0) {
|
|
cpu_abort(cpu, "Raised interrupt while not in I/O function");
|
|
}
|
|
}
|