1 /* 2 * CPU timers state API 3 * 4 * Copyright 2020 SUSE LLC 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2 or later. 7 * See the COPYING file in the top-level directory. 8 * 9 */ 10 #ifndef SYSEMU_CPU_TIMERS_H 11 #define SYSEMU_CPU_TIMERS_H 12 13 #include "qemu/timer.h" 14 15 /* init the whole cpu timers API, including icount, ticks, and cpu_throttle */ 16 void cpu_timers_init(void); 17 18 /* icount - Instruction Counter API */ 19 20 /* 21 * icount enablement state: 22 * 23 * 0 = Disabled - Do not count executed instructions. 24 * 1 = Enabled - Fixed conversion of insn to ns via "shift" option 25 * 2 = Enabled - Runtime adaptive algorithm to compute shift 26 */ 27 #ifdef CONFIG_TCG 28 extern int use_icount; 29 #define icount_enabled() (use_icount) 30 #else 31 #define icount_enabled() 0 32 #endif 33 34 /* 35 * Update the icount with the executed instructions. Called by 36 * cpus-tcg vCPU thread so the main-loop can see time has moved forward. 37 */ 38 void icount_update(CPUState *cpu); 39 40 /* get raw icount value */ 41 int64_t icount_get_raw(void); 42 43 /* return the virtual CPU time in ns, based on the instruction counter. */ 44 int64_t icount_get(void); 45 /* 46 * convert an instruction counter value to ns, based on the icount shift. 47 * This shift is set as a fixed value with the icount "shift" option 48 * (precise mode), or it is constantly approximated and corrected at 49 * runtime in adaptive mode. 50 */ 51 int64_t icount_to_ns(int64_t icount); 52 53 /* configure the icount options, including "shift" */ 54 void icount_configure(QemuOpts *opts, Error **errp); 55 56 /* used by tcg vcpu thread to calc icount budget */ 57 int64_t icount_round(int64_t count); 58 59 /* if the CPUs are idle, start accounting real time to virtual clock. */ 60 void icount_start_warp_timer(void); 61 void icount_account_warp_timer(void); 62 void icount_notify_exit(void); 63 64 /* 65 * CPU Ticks and Clock 66 */ 67 68 /* Caller must hold BQL */ 69 void cpu_enable_ticks(void); 70 /* Caller must hold BQL */ 71 void cpu_disable_ticks(void); 72 73 /* 74 * return the time elapsed in VM between vm_start and vm_stop. 75 * cpu_get_ticks() uses units of the host CPU cycle counter. 76 */ 77 int64_t cpu_get_ticks(void); 78 79 /* 80 * Returns the monotonic time elapsed in VM, i.e., 81 * the time between vm_start and vm_stop 82 */ 83 int64_t cpu_get_clock(void); 84 85 void qemu_timer_notify_cb(void *opaque, QEMUClockType type); 86 87 /* get the VIRTUAL clock and VM elapsed ticks via the cpus accel interface */ 88 int64_t cpus_get_virtual_clock(void); 89 int64_t cpus_get_elapsed_ticks(void); 90 91 #endif /* SYSEMU_CPU_TIMERS_H */ 92