diff options
Diffstat (limited to 'system/cpu-throttle.c')
-rw-r--r-- | system/cpu-throttle.c | 131 |
1 files changed, 0 insertions, 131 deletions
diff --git a/system/cpu-throttle.c b/system/cpu-throttle.c deleted file mode 100644 index 7632dc6143..0000000000 --- a/system/cpu-throttle.c +++ /dev/null @@ -1,131 +0,0 @@ -/* - * QEMU System Emulator - * - * Copyright (c) 2003-2008 Fabrice Bellard - * - * 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/thread.h" -#include "hw/core/cpu.h" -#include "qemu/main-loop.h" -#include "sysemu/cpus.h" -#include "sysemu/cpu-throttle.h" -#include "trace.h" - -/* vcpu throttling controls */ -static QEMUTimer *throttle_timer; -static unsigned int throttle_percentage; - -#define CPU_THROTTLE_PCT_MIN 1 -#define CPU_THROTTLE_PCT_MAX 99 -#define CPU_THROTTLE_TIMESLICE_NS 10000000 - -static void cpu_throttle_thread(CPUState *cpu, run_on_cpu_data opaque) -{ - double pct; - double throttle_ratio; - int64_t sleeptime_ns, endtime_ns; - - if (!cpu_throttle_get_percentage()) { - return; - } - - pct = (double)cpu_throttle_get_percentage() / 100; - throttle_ratio = pct / (1 - pct); - /* Add 1ns to fix double's rounding error (like 0.9999999...) */ - sleeptime_ns = (int64_t)(throttle_ratio * CPU_THROTTLE_TIMESLICE_NS + 1); - endtime_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + sleeptime_ns; - while (sleeptime_ns > 0 && !cpu->stop) { - if (sleeptime_ns > SCALE_MS) { - qemu_cond_timedwait_bql(cpu->halt_cond, - sleeptime_ns / SCALE_MS); - } else { - bql_unlock(); - g_usleep(sleeptime_ns / SCALE_US); - bql_lock(); - } - sleeptime_ns = endtime_ns - qemu_clock_get_ns(QEMU_CLOCK_REALTIME); - } - qatomic_set(&cpu->throttle_thread_scheduled, 0); -} - -static void cpu_throttle_timer_tick(void *opaque) -{ - CPUState *cpu; - double pct; - - /* Stop the timer if needed */ - if (!cpu_throttle_get_percentage()) { - return; - } - CPU_FOREACH(cpu) { - if (!qatomic_xchg(&cpu->throttle_thread_scheduled, 1)) { - async_run_on_cpu(cpu, cpu_throttle_thread, - RUN_ON_CPU_NULL); - } - } - - pct = (double)cpu_throttle_get_percentage() / 100; - timer_mod(throttle_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL_RT) + - CPU_THROTTLE_TIMESLICE_NS / (1 - pct)); -} - -void cpu_throttle_set(int new_throttle_pct) -{ - /* - * boolean to store whether throttle is already active or not, - * before modifying throttle_percentage - */ - bool throttle_active = cpu_throttle_active(); - - trace_cpu_throttle_set(new_throttle_pct); - - /* Ensure throttle percentage is within valid range */ - new_throttle_pct = MIN(new_throttle_pct, CPU_THROTTLE_PCT_MAX); - new_throttle_pct = MAX(new_throttle_pct, CPU_THROTTLE_PCT_MIN); - - qatomic_set(&throttle_percentage, new_throttle_pct); - - if (!throttle_active) { - cpu_throttle_timer_tick(NULL); - } -} - -void cpu_throttle_stop(void) -{ - qatomic_set(&throttle_percentage, 0); -} - -bool cpu_throttle_active(void) -{ - return (cpu_throttle_get_percentage() != 0); -} - -int cpu_throttle_get_percentage(void) -{ - return qatomic_read(&throttle_percentage); -} - -void cpu_throttle_init(void) -{ - throttle_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL_RT, - cpu_throttle_timer_tick, NULL); -} |