1. do not allow external modules to touch internal field of a timer.
2. make timer mode internal, period_in_ticks will decide the mode.
API wise:
1. the "mode" parameter was taken out of initialize_timer().
2. a new function update_timer() was added to update the timeout and
period fields.
3. the timer_expired() function was extended with an output parameter
to return the remaining cycles before expiration.
Also, the "fire_tsc" field name of hv_timer was renamed to "timeout".
With the new API, however, this change should not concern user code.
Tracked-On: #5920
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
Generalize and split basic cpu cycle/tick routines from x86/timer:
- Instead of rdstc(), use cpu_ticks() in generic code.
- Instead of get_tsc_khz(), use cpu_tickrate() in generic code.
- Include "common/ticks.h" instead of "x86/timer.h" in generic code.
- CYCLES_PER_MS is renamed to TICKS_PER_MS.
The x86 specific API rdstc() and get_tsc_khz(), as well as TSC_PER_MS
are still available in arch/x86/tsc.h but only for x86 specific usage.
Tracked-On: #5920
Signed-off-by: Rong Liu <rong2.liu@intel.com>
Signed-off-by: Yi Liang <yi.liang@intel.com>
Instead of "#include <x86/foo.h>", use "#include <asm/foo.h>".
In other words, we are adopting the same practice in Linux kernel.
Tracked-On: #5920
Signed-off-by: Liang Yi <yi.liang@intel.com>
Reviewed-by: Jason Chen CJ <jason.cj.chen@intel.com>
Requires explicit arch path name in the include directive.
The config scripts was also updated to reflect this change.
Tracked-On: #5825
Signed-off-by: Peter Fang <peter.fang@intel.com>
Reviewed-by: Jason Chen CJ <jason.cj.chen@intel.com>
This function casts a member of a structure out to the containing structure.
So rename to container_of is more readable.
Tracked-On: #4550
Signed-off-by: Li Fei1 <fei1.li@intel.com>
Count down number will be decreased at each tick, when it comes to zero,
it will trigger reschedule.
Tracked-On: #4410
Signed-off-by: Conghui Chen <conghui.chen@intel.com>
Signed-off-by: Shuo A Liu <shuo.a.liu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
pick_next function will update the virtual time parameters, and return
the vcpu thread with earlest evt. Calculate the count down number for
the picked vcpu thread, it means how many mcu a thread can run before
the next reschedule occur.
Tracked-On: #4410
Signed-off-by: Conghui Chen <conghui.chen@intel.com>
Signed-off-by: Shuo A Liu <shuo.a.liu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
In the wakeup handler, the vcpu_thread object will be inserted into the
runqueue, and in the sleep handler, it will be removed from the queue.
vcpu_thread object is ordered by EVT (effective virtual time).
Tracked-On: #4410
Signed-off-by: Conghui Chen <conghui.chen@intel.com>
Signed-off-by: Shuo A Liu <shuo.a.liu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
Add init function for bvt scheduler, creating a runqueue and a period
timer, the timer interval is default as 1ms. The interval is the minimum
charging unit.
Tracked-On: #4410
Signed-off-by: Conghui Chen <conghui.chen@intel.com>
Signed-off-by: Shuo A Liu <shuo.a.liu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
BVT (Borrowed virtual time) scheduler is used to schedule vCPUs on pCPU.
It has the concept of virtual time, vCPU with earliset virtual time is
dispatched first.
Main concepts:
tick timer:
a period tick is used to measure the physcial time in units of MCU
(minimum charing unit).
runqueue:
thread in the runqueue is ordered by virtual time.
weight:
each thread receives a share of the pCPU in proportion to its
weight.
context switch allowance:
the physcial time by which the current thread is allowed to advance
beyond the next runnable thread.
warp:
a thread with warp enabled will have a change to minus a value (Wi)
from virtual time to achieve higher priority.
virtual time:
AVT: actual virtual time, advance in proportional to weight.
EVT: effective virtual time.
EVT <- AVT - ( warp ? Wi : 0 )
SVT: scheduler virtual time, the minimum AVT in the runqueue.
Tracked-On: #4410
Signed-off-by: Conghui Chen <conghui.chen@intel.com>
Signed-off-by: Shuo A Liu <shuo.a.liu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>