include/sysemu/cpu-timers.h

   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  * ICountMode: icount enablement state:
  22  *
  23  * @ICOUNT_DISABLED: Disabled - Do not count executed instructions.
  24  * @ICOUNT_PRECISE: Enabled - Fixed conversion of insn to ns via "shift" option
  25  * @ICOUNT_ADAPTATIVE: Enabled - Runtime adaptive algorithm to compute shift
  26  */
  27 typedef enum {
  28     ICOUNT_DISABLED = 0,
  29     ICOUNT_PRECISE,
  30     ICOUNT_ADAPTATIVE,
  31 } ICountMode;
  32
  33 #if defined(CONFIG_TCG) && !defined(CONFIG_USER_ONLY)
  34 extern ICountMode use_icount;
  35 #define icount_enabled() (use_icount)
  36 #else
  37 #define icount_enabled() ICOUNT_DISABLED
  38 #endif
  39
  40 /*
  41  * Update the icount with the executed instructions. Called by
  42  * cpus-tcg vCPU thread so the main-loop can see time has moved forward.
  43  */
  44 void icount_update(CPUState *cpu);
  45
  46 /* get raw icount value */
  47 int64_t icount_get_raw(void);
  48
  49 /* return the virtual CPU time in ns, based on the instruction counter. */
  50 int64_t icount_get(void);
  51 /*
  52  * convert an instruction counter value to ns, based on the icount shift.
  53  * This shift is set as a fixed value with the icount "shift" option
  54  * (precise mode), or it is constantly approximated and corrected at
  55  * runtime in adaptive mode.
  56  */
  57 int64_t icount_to_ns(int64_t icount);
  58
  59 /**
  60  * icount_configure: configure the icount options, including "shift"
  61  * @opts: Options to parse
  62  * @errp: pointer to a NULL-initialized error object
  63  *
  64  * Return: true on success, else false setting @errp with error
  65  */
  66 bool icount_configure(QemuOpts *opts, Error **errp);
  67
  68 /* used by tcg vcpu thread to calc icount budget */
  69 int64_t icount_round(int64_t count);
  70
  71 /* if the CPUs are idle, start accounting real time to virtual clock. */
  72 void icount_start_warp_timer(void);
  73 void icount_account_warp_timer(void);
  74 void icount_notify_exit(void);
  75
  76 /*
  77  * CPU Ticks and Clock
  78  */
  79
  80 /* Caller must hold BQL */
  81 void cpu_enable_ticks(void);
  82 /* Caller must hold BQL */
  83 void cpu_disable_ticks(void);
  84
  85 /*
  86  * return the time elapsed in VM between vm_start and vm_stop.
  87  * cpu_get_ticks() uses units of the host CPU cycle counter.
  88  */
  89 int64_t cpu_get_ticks(void);
  90
  91 /*
  92  * Returns the monotonic time elapsed in VM, i.e.,
  93  * the time between vm_start and vm_stop
  94  */
  95 int64_t cpu_get_clock(void);
  96
  97 void qemu_timer_notify_cb(void *opaque, QEMUClockType type);
  98
  99 /* get the VIRTUAL clock and VM elapsed ticks via the cpus accel interface */
 100 int64_t cpus_get_virtual_clock(void);
 101 int64_t cpus_get_elapsed_ticks(void);
 102
 103 #endif /* SYSEMU_CPU_TIMERS_H */