frostfs-node/pkg/morph/timer/block.go
Alex Vanin 67b3682348 [] morph/timer: Add single tick timer
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2021-07-22 15:20:34 +03:00

187 lines
3.2 KiB
Go

package timer
import (
"sync"
)
// BlockMeter calculates block time interval dynamically.
type BlockMeter func() (uint32, error)
// BlockTickHandler is a callback of a certain block advance.
type BlockTickHandler func()
// BlockTimer represents block timer.
//
// It can tick the blocks and perform certain actions
// on block time intervals.
type BlockTimer struct {
rolledBack bool
mtx *sync.Mutex
dur BlockMeter
baseDur uint32
mul, div uint32
cur, tgt uint32
h BlockTickHandler
ps []BlockTimer
once bool
deltaCfg
}
// DeltaOption is an option of delta-interval handler.
type DeltaOption func(*deltaCfg)
type deltaCfg struct {
pulse bool
}
// WithPulse returns option to call delta-interval handler multiple
// times
func WithPulse() DeltaOption {
return func(c *deltaCfg) {
c.pulse = true
}
}
// StaticBlockMeter returns BlockMeters that always returns (d, nil).
func StaticBlockMeter(d uint32) BlockMeter {
return func() (uint32, error) {
return d, nil
}
}
// NewBlockTimer creates a new BlockTimer.
//
// Reset should be called before timer ticking.
func NewBlockTimer(dur BlockMeter, h BlockTickHandler) *BlockTimer {
return &BlockTimer{
mtx: new(sync.Mutex),
dur: dur,
mul: 1,
div: 1,
h: h,
deltaCfg: deltaCfg{
pulse: true,
},
}
}
// NewOneTickTimer creates a new BlockTimer that ticks only once.
//
// Do not use delta handlers with pulse in this timer.
func NewOneTickTimer(dur BlockMeter, h BlockTickHandler) *BlockTimer {
return &BlockTimer{
mtx: new(sync.Mutex),
dur: dur,
mul: 1,
div: 1,
h: h,
once: true,
}
}
// OnDelta registers handler which is executed on (mul / div * BlockMeter()) block
// after basic interval reset.
//
// If WithPulse option is provided, handler is executed (mul / div * BlockMeter()) block
// during base interval.
func (t *BlockTimer) OnDelta(mul, div uint32, h BlockTickHandler, opts ...DeltaOption) {
c := deltaCfg{
pulse: false,
}
for i := range opts {
opts[i](&c)
}
t.ps = append(t.ps, BlockTimer{
mul: mul,
div: div,
h: h,
once: t.once,
deltaCfg: c,
})
}
// Reset resets previous ticks of the BlockTimer.
//
// Returns BlockMeter's error upon occurrence.
func (t *BlockTimer) Reset() error {
d, err := t.dur()
if err != nil {
return err
}
t.mtx.Lock()
t.resetWithBaseInterval(d)
for i := range t.ps {
t.ps[i].resetWithBaseInterval(d)
}
t.mtx.Unlock()
return nil
}
func (t *BlockTimer) resetWithBaseInterval(d uint32) {
t.rolledBack = false
t.baseDur = d
t.reset()
}
func (t *BlockTimer) reset() {
mul, div := t.mul, t.div
if !t.pulse && t.rolledBack && mul < div {
mul, div = 1, 1
}
delta := mul * t.baseDur / div
if delta == 0 {
delta = 1
}
t.tgt = delta
t.cur = 0
}
// Tick ticks one block in the BlockTimer.
//
// Executes all callbacks which are awaiting execution at the new block.
func (t *BlockTimer) Tick() {
t.mtx.Lock()
t.tick()
t.mtx.Unlock()
}
func (t *BlockTimer) tick() {
t.cur++
if t.cur == t.tgt {
// it would be advisable to optimize such execution, for example:
// 1. push handler to worker pool t.wp.Submit(h);
// 2. call t.tickH(h)
t.h()
if !t.once {
t.cur = 0
t.rolledBack = true
t.reset()
}
}
for i := range t.ps {
t.ps[i].tick()
}
}