racket/collects/tests/mzscheme/sync.ss

1141 lines
37 KiB
Scheme

(load-relative "loadtest.ss")
(Section 'synchronization)
(define SYNC-SLEEP-DELAY 0.025)
(define SYNC-BUSY-DELAY 0.1) ; go a little slower to check busy waits
;; ----------------------------------------
;; Semaphore peeks
(let* ([s (make-semaphore)]
[p (semaphore-peek-evt s)]
[ch (make-channel)])
(test #f sync/timeout 0 s p)
(test #f sync/timeout 0 s p)
(semaphore-post s)
(test p sync/timeout 0 p)
(test p sync p)
(test s sync s)
(test #f sync/timeout 0 p)
(thread (lambda () (sync (system-idle-evt)) (semaphore-post s)))
(test p sync p)
(test p sync p)
(test s sync s)
(test #f sync/timeout 0 p)
(thread (lambda () (sync/timeout 0 p) (channel-put ch 7)))
(thread (lambda () (sync/timeout 0 p) (channel-put ch 7)))
(thread (lambda () (sync/timeout 0 p) (channel-put ch 7)))
(semaphore-post s)
(test 7 channel-get ch)
(test 7 channel-get ch)
(test 7 channel-get ch)
(test #f channel-try-get ch)
(thread (lambda () (channel-put ch 9)))
(sync (system-idle-evt))
(test 9 channel-try-get ch)
(test #f channel-try-get ch))
(arity-test semaphore-peek-evt 1 1)
(err/rt-test (semaphore-peek-evt #f))
(err/rt-test (semaphore-peek-evt (semaphore-peek-evt (make-semaphore))))
;; ----------------------------------------
;; Channels
(arity-test make-channel 0 0)
(let ([c (make-channel)]
[v 'nope])
(test #f sync/timeout 0 c)
(thread (lambda () (sync (system-idle-evt)) (set! v (channel-get c))))
(test (void) channel-put c 10)
(sync (system-idle-evt))
(test 10 'thread-v v)
(thread (lambda () (sync (system-idle-evt)) (channel-put c 11)))
(test #f sync/timeout 0 c)
(test 11 sync c)
(let ([p (channel-put-evt c 45)])
(thread (lambda () (sync (system-idle-evt)) (set! v (sync c))))
(test #f sync/timeout 0 p)
(test p sync p)
(test #f sync/timeout 0 p)
(sync (system-idle-evt))
(test 45 'thread-v v))
;;;;; Make sure break/kill before action => break/kill only
;; get:
(let ([try (lambda (break-thread)
(let ([t (thread (lambda ()
(set! v (channel-get c))))])
(test #t thread-running? t)
(sync (system-idle-evt))
(test #t thread-running? t)
(test (void) break-thread t)
(test #f sync/timeout 0 (channel-put-evt c 32))
(sync (system-idle-evt))
(test #f thread-running? t)
(test 45 'old-v v)))])
(try break-thread)
(try kill-thread))
;; put:
(let ([try (lambda (break-thread)
(let ([t (thread (lambda () (channel-put c 17)))])
(test #t thread-running? t)
(sync (system-idle-evt))
(test #t thread-running? t)
(test (void) break-thread t)
(test #f sync/timeout 0 c)
(sync (system-idle-evt))
(test #f thread-running? t)))])
(try break-thread)
(try kill-thread))
;; put in main thread:
(let ([t (current-thread)])
(thread (lambda ()
(sync (system-idle-evt))
(break-thread t)
(set! v (channel-get c)))))
(test 77
'broken
(with-handlers ([exn:break? (lambda (x) 77)])
(sync (channel-put-evt c 32))))
(test 45 'old-v v)
(channel-put c 89)
(sleep)
(test 89 'new-v v)
;; get in main thread:
(let ([t (current-thread)])
(thread (lambda ()
(sync (system-idle-evt))
(break-thread t)
(channel-put c 66))))
(test 99
'broken
(with-handlers ([exn:break? (lambda (x) 99)])
(sync c)))
(test 66 sync/timeout 0 c)
;;; Can't sync with self!
(test #f sync/timeout 0 c (channel-put-evt c 100))
;; Test cross sync:
(let ([c2 (make-channel)]
[ok-result? (lambda (r)
(or (eq? r 100) (evt? r)))])
(thread (lambda () (channel-put c2 (sync c (channel-put-evt c 100)))))
(thread (lambda () (channel-put c2 (sync c (channel-put-evt c 100)))))
(test #t ok-result? (channel-get c2))
(test #t ok-result? (channel-get c2))))
;; ----------------------------------------
;; Alarms
(test #f sync/timeout 0.1 (alarm-evt (+ (current-inexact-milliseconds) 200)))
(test 'ok sync/timeout 0.1
(wrap-evt
(alarm-evt (+ (current-inexact-milliseconds) 50))
(lambda (x) 'ok)))
(test 'ok sync/timeout 100
(wrap-evt
(alarm-evt (+ (current-inexact-milliseconds) 50))
(lambda (x) 'ok)))
;; ----------------------------------------
;; Waitable sets
(err/rt-test (choice-evt 7))
(err/rt-test (choice-evt (make-semaphore) 7))
(arity-test choice-evt 0 -1)
(test #f sync/timeout SYNC-SLEEP-DELAY (choice-evt))
(test #f sync/timeout SYNC-SLEEP-DELAY (choice-evt) (choice-evt))
(test #f sync/timeout SYNC-SLEEP-DELAY (choice-evt (choice-evt) (choice-evt)))
(let ([s1 (make-semaphore)]
[s2 (make-semaphore)]
[s3 (make-semaphore)])
(test #f sync/timeout SYNC-SLEEP-DELAY (choice-evt s1 s2 s3))
(semaphore-post s2)
(test s2 sync/timeout SYNC-SLEEP-DELAY (choice-evt s1 s2 s3))
(test #f sync/timeout SYNC-SLEEP-DELAY (choice-evt s1 s2 s3))
(let ([set (choice-evt s1 s2 s3)])
(test #f sync/timeout SYNC-SLEEP-DELAY set)
(semaphore-post s2)
(test s2 sync/timeout SYNC-SLEEP-DELAY set)
(test #f sync/timeout SYNC-SLEEP-DELAY set))
(thread (lambda () (sleep) (semaphore-post s3)))
(test s3 sync/timeout SYNC-SLEEP-DELAY (choice-evt s1 s2 s3))
(test #f sync/timeout SYNC-SLEEP-DELAY (choice-evt s1 s2 s3))
(semaphore-post s3)
(test s3 sync/timeout SYNC-SLEEP-DELAY s1 (choice-evt s2 s3))
(test #f sync/timeout SYNC-SLEEP-DELAY s1 (choice-evt s2 s3))
(semaphore-post s3)
(test s3 sync/timeout SYNC-SLEEP-DELAY (choice-evt s1 s2) s3)
(test #f sync/timeout SYNC-SLEEP-DELAY (choice-evt s1 s2) s3)
(let ([set (choice-evt s1 s2)])
(test #f sync/timeout SYNC-SLEEP-DELAY s1 set s3)
(semaphore-post s2)
(test s2 sync/timeout SYNC-SLEEP-DELAY set s3)
(test #f sync/timeout SYNC-SLEEP-DELAY set s3))
(test #f sync/timeout SYNC-SLEEP-DELAY (choice-evt s1 (choice-evt s2 s3)))
(semaphore-post s3)
(test s3 sync/timeout SYNC-SLEEP-DELAY (choice-evt s1 (choice-evt s2 s3)))
(test #f sync/timeout SYNC-SLEEP-DELAY (choice-evt s1 (choice-evt s2 s3)))
(semaphore-post s3)
(test s3 sync/timeout SYNC-SLEEP-DELAY (choice-evt (choice-evt s1 s2) s3))
(test #f sync/timeout SYNC-SLEEP-DELAY (choice-evt (choice-evt s1 s2) s3))
(let ([set (choice-evt s1 (choice-evt s2 s3))])
(test #f sync/timeout SYNC-SLEEP-DELAY set)
(semaphore-post s3)
(test s3 sync/timeout SYNC-SLEEP-DELAY set)
(test #f sync/timeout SYNC-SLEEP-DELAY set))
(let* ([c (make-channel)]
[set (choice-evt s1 s2 c)])
(test #f sync/timeout SYNC-SLEEP-DELAY set)
(thread (lambda () (channel-put c 12)))
(test 12 sync/timeout SYNC-SLEEP-DELAY set)
(test #f sync/timeout SYNC-SLEEP-DELAY set)
(let* ([p (channel-put-evt c 85)]
[set (choice-evt s1 s2 p)])
(test #f sync/timeout SYNC-SLEEP-DELAY set)
(thread (lambda () (channel-get c)))
(test p sync/timeout SYNC-SLEEP-DELAY set)
(test #f sync/timeout SYNC-SLEEP-DELAY set))))
(test 77 sync/timeout
#f
(wrap-evt (make-semaphore) void)
(guard-evt
(lambda ()
(choice-evt
(make-semaphore) (make-semaphore) (make-semaphore) (make-semaphore)
(make-semaphore) (make-semaphore) (make-semaphore) (make-semaphore)
(let ([sema (make-semaphore 1)])
(wrap-evt sema (lambda (x)
(test sema values x)
77)))))))
;; More alarms:
(let ([make-delay
(lambda (amt)
(guard-evt
(lambda ()
(wrap-evt
(alarm-evt (+ (current-inexact-milliseconds) (* 1000 amt)))
(lambda (v) amt)))))])
(test #f sync/timeout 0.1 (make-delay 0.15) (make-delay 0.2))
(test 0.15 sync/timeout 18 (make-delay 0.15) (make-delay 0.2))
(test 0.15 sync/timeout 18 (make-delay 0.2) (make-delay 0.15))
(test 0.15 sync/timeout 0.18 (make-delay 0.15) (make-delay 0.2))
(test 0.15 sync/timeout 18
(choice-evt (make-delay 0.2) (make-delay 0.15))))
;; ----------------------------------------
;; Wrapped waitables
(arity-test wrap-evt 2 2)
(err/rt-test (wrap-evt 1 void))
(err/rt-test (wrap-evt (make-semaphore) 10))
(err/rt-test (wrap-evt (make-semaphore) (lambda () 10)))
(test 17 sync (wrap-evt (make-semaphore 1) (lambda (sema) 17)))
(test 17 sync (choice-evt
(make-semaphore)
(wrap-evt (make-semaphore 1) (lambda (sema) 17))))
(test #t sync (wrap-evt (make-semaphore 1) semaphore?))
(test 18 'sync
(let ([n 17]
[s (make-semaphore)])
(thread (lambda () (sync (system-idle-evt)) (semaphore-post s)))
(sync
(wrap-evt
s
(lambda (sema) (set! n (add1 n)) n))
(wrap-evt
s
(lambda (sema) (set! n (add1 n)) n)))))
(let ([c (make-channel)])
(thread (lambda () (channel-put c 76)))
(test 77 sync (wrap-evt c add1)))
(test 78 sync
(wrap-evt (choice-evt (make-semaphore 1) (make-semaphore 1))
(lambda (x) 78)))
;; ----------------------------------------
;; Nack waitables
(arity-test nack-guard-evt 1 1)
(arity-test guard-evt 1 1)
(err/rt-test (nack-guard-evt 10))
(err/rt-test (nack-guard-evt (lambda () 10)))
(err/rt-test (guard-evt 10))
(err/rt-test (guard-evt (lambda (x) 10)))
(let ([s (make-semaphore 1)]
[nack-try-wait? (lambda (n)
(unless (evt? n)
(error "NACK isn't ready for try-wait"))
(let ([v (sync/timeout 0 n)])
(when v
(test #t void? v)
(test (void) sync n))
(and v #t)))])
(test s sync (nack-guard-evt (lambda (nack) s)))
(test #f semaphore-try-wait? s)
(semaphore-post s)
(let ([v #f])
(test #f sync/timeout 0
(nack-guard-evt (lambda (nack)
(set! v nack)
(make-semaphore))))
(test #t nack-try-wait? v)
(set! v #f)
(test #f sync/timeout SYNC-SLEEP-DELAY
(nack-guard-evt (lambda (nack)
(set! v nack)
(make-semaphore))))
(test #t nack-try-wait? v)
(set! v #f)
(test #f sync/timeout 0
(nack-guard-evt (lambda (nack)
(set! v nack)
(make-semaphore)))
(nack-guard-evt (lambda (nack)
(set! v nack)
(make-semaphore))))
(test #t nack-try-wait? v)
(set! v #f)
(test #f sync/timeout SYNC-SLEEP-DELAY
(nack-guard-evt (lambda (nack)
(set! v nack)
(make-semaphore)))
(nack-guard-evt (lambda (nack)
(set! v nack)
(make-semaphore))))
(test #t nack-try-wait? v)
(set! v #f)
(test #f sync/timeout SYNC-SLEEP-DELAY
(choice-evt
(nack-guard-evt (lambda (nack)
(set! v nack)
(make-semaphore)))
(nack-guard-evt (lambda (nack)
(set! v nack)
(make-semaphore)))))
(test #t nack-try-wait? v)
(set! v #f)
(test s sync/timeout 0
(nack-guard-evt (lambda (nack)
(set! v nack)
s)))
(test #f nack-try-wait? v) ; ... but not an exception!
(semaphore-post s)
(set! v #f)
(let loop ()
(test s sync/timeout 0
(nack-guard-evt (lambda (nack)
(set! v nack)
(make-semaphore)))
s)
(if v
(test #t nack-try-wait? v)
(begin ; tried the 2nd first, so do test again
(semaphore-post s)
(loop))))
(set! v #f)
(let loop ()
(err/rt-test (sync/timeout 0
(nack-guard-evt (lambda (nack)
(set! v nack)
(make-semaphore)))
(nack-guard-evt (lambda (nack)
(/ 1 0))))
exn:fail:contract:divide-by-zero?)
(if v
(test #t nack-try-wait? v)
(loop)))
(set! v #f)
(let loop ()
(err/rt-test (sync/timeout 0
(nack-guard-evt (lambda (nack)
(/ 10 0)))
(nack-guard-evt (lambda (nack)
(set! v nack)
(make-semaphore))))
exn:fail:contract:divide-by-zero?)
(if v
(begin
(set! v #f)
(loop))
(test #t not v)))
(set! v null)
(test #f sync/timeout 0
(nack-guard-evt (lambda (nack)
(set! v (cons nack v))
(make-semaphore)))
(nack-guard-evt (lambda (nack)
(set! v (cons nack v))
(make-semaphore))))
(test '(#t #t) map nack-try-wait? v)
;; Check that thread kill also implies nack:
(set! v #f)
(let* ([ready (make-semaphore)]
[t (thread (lambda ()
(sync/timeout
#f
(nack-guard-evt
(lambda (nack)
(set! v nack)
(semaphore-post ready)
(make-semaphore))))))])
(semaphore-wait ready)
(kill-thread t)
(test #t nack-try-wait? v))))
(let ([s (make-semaphore 1)])
(test s sync/timeout 0 (guard-evt (lambda () s))))
(let ([v #f])
(test #f sync/timeout 0
(nack-guard-evt
(lambda (nack)
(set! v nack)
(choice-evt (make-semaphore) (make-semaphore)))))
(unless (evt? v) (error "the NACK isn't ready!"))
(test (void) sync/timeout 0 v))
(let ([ch (make-channel)]
[n #f])
(let ([t (thread
(lambda ()
(sync
(nack-guard-evt
(lambda (nack)
(set! n nack)
never-evt))
(channel-put-evt ch 10))))])
(sync (system-idle-evt))
(test 10 channel-get ch)
(test (void) sync/timeout 0 n)))
;; ----------------------------------------
;; Poll waitables
(arity-test poll-guard-evt 1 1)
(err/rt-test (poll-guard-evt 10))
(err/rt-test (poll-guard-evt (lambda () 10)))
(let ([s (semaphore-peek-evt (make-semaphore 1))])
(test s sync/timeout 0 (poll-guard-evt (lambda (poll?)
(test #t values poll?)
s)))
(test s sync (poll-guard-evt (lambda (poll?)
(test #f values poll?)
s)))
(test s sync/timeout 0 (choice-evt
(poll-guard-evt (lambda (poll?)
(test #t values poll?)
s))
(make-semaphore)))
(test s sync (choice-evt
(poll-guard-evt (lambda (poll?)
(test #f values poll?)
s))
(make-semaphore))))
;; ----------------------------------------
;; Structures as waitables
;; Bad property value:
(err/rt-test (make-struct-type 'wt #f 2 0 #f (list (cons prop:evt -1))) exn:application:mismatch?)
;; slot index 1 not immutable:
(err/rt-test (make-struct-type 'wt #f 2 0 #f (list (cons prop:evt 1))) exn:application:mismatch?)
(define-values (struct:wt make-wt wt? wt-ref wt-set!)
(make-struct-type 'wt #f 2 0 #f (list (cons prop:evt 1)) (make-inspector) #f '(1)))
(define-values (struct:wt2 make-wt2 wt2? wt2-ref wt2-set!)
(make-struct-type 'wt2 #f 2 0 #f (list (cons prop:evt 1))
(make-inspector) 0 '(1)))
(let ([test-wt
(lambda (make-wt)
(let ([always-ready (make-wt (lambda () 10) (lambda (self) #t))]
[always-stuck (make-wt 1 2)])
(test always-ready sync always-ready)
(test always-ready sync/timeout 0 always-ready)
(test #f sync/timeout 0 always-stuck)
(test #f sync/timeout SYNC-SLEEP-DELAY always-stuck)))])
(test-wt make-wt)
(test-wt make-wt2))
;; Check whether something that takes at least SYNC-SLEEP-DELAY
;; seconds in fact takes roughly that much CPU time. We
;; expect non-busy-wait takes to take a very small fraction
;; of the time.
;; This test only works well if there are no other
;; threads running and the underlying OS is not loaded.
(define (check-busy-wait go busy?)
(collect-garbage) ; reduces false-positives in detecting busy wait
(let ([msecs (current-process-milliseconds)]
[gc-msecs (current-gc-milliseconds)]
[real-msecs (current-milliseconds)])
(go)
(let ([took (/ (abs (- (current-process-milliseconds) msecs
(abs (- (current-gc-milliseconds) gc-msecs))))
1000.0)]
[real-took (/ (abs (- (current-milliseconds) real-msecs)) 1000.0)]
[boundary (/ SYNC-BUSY-DELAY 6)])
;; Hack.
;; The following test isn't reliable, so only Matthew should see it,
;; and only in non-parallel mode:
(when (and (regexp-match #rx"(mflatt)|(matthewf)" (path->string (find-system-path 'home-dir)))
(equal? "" Section-prefix))
(test busy? (lambda (a ax b c d) (> b c)) 'busy-wait? go took boundary real-took)))))
(define (test-good-waitable wrap-sema make-wt)
(let ([sema (make-semaphore)])
(letrec-values ([(sema-ready-part get-sema-result) (wrap-sema sema sema (lambda () sema-ready))]
[(sema-ready) (make-wt 1 sema-ready-part)])
(test #f 'initial-sema (sync/timeout 0 sema-ready))
(semaphore-post sema)
(test (get-sema-result) sync/timeout 0 sema-ready)
(test #f semaphore-try-wait? sema)
(test #f sync/timeout 0 sema-ready)
(semaphore-post sema)
(let ()
(define (non-busy-wait waitable get-result)
(begin
(thread (lambda ()
(sync (system-idle-evt))
(semaphore-post sema)))
(test (get-result) sync waitable))
(test #f sync/timeout 0 waitable)
(semaphore-post sema)
(test (get-result) sync waitable)
(test #f sync/timeout 0 waitable)
(semaphore-post sema)
(test (get-result) sync waitable)
(test #f semaphore-try-wait? sema)
(test #f sync/timeout 0 waitable))
(non-busy-wait sema-ready get-sema-result)
(semaphore-post sema)
(letrec-values ([(wrapped-part get-wrapped-result)
(wrap-sema (make-wt 2 (lambda (self) sema-ready))
(get-sema-result)
(lambda () sema-ready))]
[(wrapped) (make-wt 3 wrapped-part)])
(non-busy-wait (get-wrapped-result) get-wrapped-result))))))
(map
(lambda (make-wt)
(test-good-waitable (lambda (x x-result get-self)
(values x (lambda () x-result)))
make-wt)
(test-good-waitable (lambda (x x-result get-self)
(let ([ws (choice-evt
x
(make-wt 99 (lambda (self) (make-semaphore))))])
(values ws (lambda () x-result))))
make-wt))
(list make-wt make-wt2))
(check-busy-wait
(letrec ([s (make-semaphore)]
[wt (make-wt 1 (lambda (self) (unless (or (eq? wt s)
(eq? self wt) )
(error 'wt "yikes: ~s != ~s" self wt))
wt))])
(thread (lambda () (sleep (/ SYNC-BUSY-DELAY 2)) (set! wt s)))
(lambda ()
(test #f sync/timeout SYNC-BUSY-DELAY wt)))
#t)
;; ----------------------------------------
(define (test-stuck-port ready-waitable make-waitable-unready make-waitable-ready)
(let* ([go? #f]
[bad-stuck-port (make-input-port
'name
(lambda (str)
(if go?
(begin
(bytes-set! str 0 (char->integer #\x))
1)
(if (zero? (random 2))
0
ready-waitable)))
#f
void)])
(make-waitable-unready ready-waitable)
(test #f char-ready? bad-stuck-port)
(test #f sync/timeout SYNC-SLEEP-DELAY bad-stuck-port)
(test 0 read-bytes-avail!* (make-bytes 10) bad-stuck-port)
(set! go? #t)
(test #t char-ready? bad-stuck-port)
(test bad-stuck-port sync/timeout SYNC-SLEEP-DELAY bad-stuck-port)
(test #t positive? (read-bytes-avail!* (make-bytes 10) bad-stuck-port))
(set! go? #f)
(test #f char-ready? bad-stuck-port)
(test #f sync/timeout SYNC-SLEEP-DELAY bad-stuck-port)
(test 0 read-bytes-avail!* (make-bytes 10) bad-stuck-port)
(set! ready-waitable 0)
(test #f sync/timeout 0 bad-stuck-port)
(test #f sync/timeout 0 bad-stuck-port)
(check-busy-wait
(lambda ()
(test #f sync/timeout SYNC-BUSY-DELAY bad-stuck-port))
#t)
(check-busy-wait
(lambda ()
(thread (lambda ()
(sleep SYNC-BUSY-DELAY)
(set! go? #t)))
(test bad-stuck-port sync bad-stuck-port))
#t)))
(map
(lambda (make-wt)
(test-stuck-port (make-semaphore 1) semaphore-try-wait? semaphore-post)
(let ([ready? #t])
(test-stuck-port (make-wt 77 (lambda (self)
(if ready?
#t
(make-semaphore))))
(lambda (wt) (set! ready? #f))
(lambda (wt) (set! ready? #t))))
(let ([s (make-semaphore 1)])
(test-stuck-port (make-wt 77 s)
(lambda (wt) (semaphore-try-wait? s))
(lambda (wt) (semaphore-post s))))
(let ([s (make-semaphore 1)])
(test-stuck-port (make-wt 177 (lambda (self) s))
(lambda (wt) (semaphore-try-wait? s))
(lambda (wt) (semaphore-post s)))))
(list make-wt make-wt2))
;; ----------------------------------------
;; In the current implemenation, a depth of 10 for
;; waitable chains is a magic number; it causes the scheduler to
;; swap a thread in to check whether it can run, instead of
;; checking in the thread. (For a well-behaved chain, this
;; swap in will lead to a more friendly semaphore wait, for
;; example.)
(letrec ([stack-em (lambda (n s)
;; This needs to be tail-recursive to
;; the find-depth check below (to check
;; blocking depth, not precdure depth)
(if (zero? n)
s
(stack-em (sub1 n) (make-wt n s))))])
(let* ([s1 (make-semaphore 1)]
[s20 (make-semaphore 1)]
[wt1 (stack-em 1 s1)]
[wt20 (stack-em 20 s20)])
(test s1 sync/timeout 0 wt1)
(test s20 sync/timeout 0 wt20)
(test #f semaphore-try-wait? s1)
(test #f semaphore-try-wait? s20)
(let ([t20
(thread (lambda ()
(test s20 sync/timeout 1.0 wt20)))])
(let loop ([n 20])
(unless (zero? n)
(sleep)
(loop (sub1 n))))
(semaphore-post s20)
(test (void) thread-wait t20))))
;; ----------------------------------------
;; Thread suspend, resume, and dead waitables
(let ([d (thread-dead-evt (thread void))])
(test d sync d))
(let* ([sema (make-semaphore)]
[t (thread (lambda () (semaphore-wait sema)))]
[r (thread-resume-evt t)]
[s (thread-suspend-evt t)])
(test #f sync/timeout 0 t s)
(test t sync/timeout 0 t s r)
(test t sync/timeout 0 r)
(thread-suspend t)
(test t sync/timeout 0 r)
(test t sync/timeout 0 s)
(let* ([r (thread-resume-evt t)]
[s (thread-suspend-evt t)])
(test #f sync/timeout 0 t r)
(test t sync/timeout 0 t s r)
(test t sync/timeout 0 s)
(thread-resume t)
(test t sync/timeout 0 s)
(test t sync/timeout 0 r)
(let* ([s (thread-suspend-evt t)])
(thread (lambda () (sync (system-idle-evt)) (thread-suspend t)))
(test #f sync/timeout 0 s)
(test t sync s)
(let* ([r (thread-resume-evt t)]
[d (thread-dead-evt t)])
(thread (lambda () (sync (system-idle-evt)) (thread-resume t)))
(test #f sync/timeout 0 r)
(test t sync r)
(test #f sync/timeout 0 d)
(semaphore-post sema)
(test d sync d)
(test t sync r)
(test t sync s)
(test #f sync/timeout 0 (thread-resume-evt t))
(test #f sync/timeout 0 (thread-suspend-evt t))
(test d thread-dead-evt t)))))
;; ----------------------------------------
;; thread mbox
(test #f thread-try-receive)
(test #f sync/timeout 0 (thread-receive-evt))
(test (void) thread-send (current-thread) 10)
(let ([t (thread-receive-evt)])
(test t sync/timeout 10 t))
(test 10 thread-try-receive)
(test #f thread-try-receive)
(let ([t (current-thread)])
(thread (lambda ()
(sync (system-idle-evt))
(thread-send t 35))))
(test 35 thread-receive)
(test #f thread-try-receive)
(test (void) thread-rewind-receive '(1 2 3))
(test 3 thread-try-receive)
(test 2 thread-try-receive)
(test (void) thread-rewind-receive '(4))
(test 4 thread-try-receive)
(test 1 thread-try-receive)
(test #f thread-try-receive)
(test (void) thread-rewind-receive (vector->list (make-vector 500 'x)))
(let loop ([n 500])
(unless (zero? n)
(test 'x thread-try-receive)
(loop (sub1 n))))
(test #f thread-try-receive)
(let* ([s #f]
[t1 (let ([t (current-thread)])
(thread (lambda ()
(set! s (thread-receive)))))])
(sync (system-idle-evt))
(thread-suspend t1)
(thread-send t1 'apple)
(sync (system-idle-evt))
(test #f values s)
(thread-resume t1)
(sync (system-idle-evt))
(test 'apple values s))
(let* ([s 0]
[t (thread (lambda ()
(set! s (list (thread-receive)
(thread-receive)
(thread-receive)))))])
(thread-send t 0)
(thread-send t 1)
(thread-send t 2)
(sync (system-idle-evt))
(test '(0 1 2) values s))
(let ([t (thread void)])
(sync (system-idle-evt))
(test 'z thread-send t 'x (lambda () 'z))
(test-values '(a z) (lambda ()
(thread-send t 'x (lambda () (values 'a 'z)))))
(err/rt-test (thread-send t 'x)))
;; make sure it's ok for rewind to be the first action:
(test (void) thread-wait (thread (lambda () (thread-rewind-receive '(1 2 3)))))
;; ----------------------------------------
;; Garbage collection
(define (num-scheduled)
(let ([v (make-vector 7)])
(vector-set-performance-stats! v)
(vector-ref v 6)))
(define (check-threads-gcable label blocking-thunk)
;; Actually, we approximate the gcable check as a num-scheduled check,
;; even though there's still a lot of machinery here to try to check
;; GCing. The explicit gc has been commented out.
(define orig-scheduled (num-scheduled))
(let ([l (let loop ([n 20][die? #f])
(if (zero? n)
null
(cons (make-weak-box (thread (if die? void blocking-thunk)))
(loop (if die? n (sub1 n)) (not die?)))))]
[sl (lambda ()
(let loop ([n 20])
(unless (zero? n) (sleep) (loop (sub1 n)))))]
[ok-done? (lambda (r)
(or (<= (list-ref r 3) orig-scheduled)
;; If we're running parallel threads,
;; just give up on the comparison.
(not (equal? "" Section-prefix))))])
(test #t
ok-done?
(let loop ([tries 0][n 100])
(if (or (= tries 3) (< n 10))
(list tries n label (num-scheduled))
(begin
(sl)
;; (collect-garbage)
(loop (add1 tries)
(apply + (map (lambda (b) (if (weak-box-value b) 1 0)) l)))))))))
(check-threads-gcable 'sema (lambda () (semaphore-wait (make-semaphore))))
(define (check/combine c)
(check-threads-gcable 'semaw (lambda () (sync (c (make-semaphore)))))
(check-threads-gcable 'semap (lambda () (sync (c (semaphore-peek-evt (make-semaphore))))))
(check-threads-gcable 'ch (lambda () (sync (c (make-channel)))))
(check-threads-gcable 'chput (lambda () (sync (c (channel-put-evt (make-channel) 10)))))
(check-threads-gcable 'wrapped (lambda () (sync (c (wrap-evt (make-semaphore) void)))))
(check-threads-gcable 'guard (lambda () (sync (c (guard-evt (lambda () (make-semaphore)))))))
(check-threads-gcable 'nack (lambda () (sync (c (nack-guard-evt (lambda (nack) (make-semaphore)))))))
(check-threads-gcable 'poll (lambda () (sync (c (poll-guard-evt (lambda (poll?) (make-semaphore)))))))
(check-threads-gcable 'never (lambda () (sync (c never-evt)))))
(check/combine values)
(check/combine (lambda (x) (choice-evt x (make-semaphore))))
(check/combine (lambda (x) (choice-evt (make-semaphore) x)))
(check/combine (lambda (x) (choice-evt (make-semaphore) x)))
(check-threads-gcable 'nested (lambda () (call-in-nested-thread (lambda () (semaphore-wait (make-semaphore))))))
(pseudo-random-generator? 10)
(check-threads-gcable 'suspended (lambda () (thread-suspend (current-thread))))
(check-threads-gcable 'nested-suspend (lambda () (call-in-nested-thread (lambda () (thread-suspend (current-thread))))))
(check-threads-gcable 'resume (lambda () (let ([t (thread (lambda () (sleep 10)))])
(thread-suspend t)
(sync (thread-resume-evt t)))))
(check-threads-gcable 'suspend (lambda () (let ([t (thread (lambda () (semaphore-wait (make-semaphore))))])
(sync (thread-suspend-evt t)))))
(check-threads-gcable 'suspend-self (lambda () (sync (thread-suspend-evt (current-thread)))))
;; ----------------------------------------
;; Fairness in wait selection
(let ([try (lambda (t1 t2 r min max)
(test #t
<
min
(let loop ([n 100][r-n 0])
(if (zero? n)
r-n
(loop (sub1 n) (+ r-n
(if (eq? r (sync t1 t2))
1
0)))))
max))])
(let ([t1 (semaphore-peek-evt (make-semaphore 1))]
[t2 (semaphore-peek-evt (make-semaphore 1))])
(let-values ([(r w) (make-pipe)])
(fprintf w "Hi!~n")
;; Between 20% and 80% is fair, and surely < 20% or > 80% is unlikely
(try t1 t2 t1 20 80)
(try t1 t2 t2 20 80)
(try t1 w w 20 80)
(try w t1 w 20 80)
(try t1 (choice-evt t2 w) t1 10 50)
(try t1 (choice-evt t2 w) w 10 50)
(try (choice-evt t2 w) t1 w 10 50))))
;; ----------------------------------------
;; No starvation, despite hack to increase throughput for
;; semaphore-protected data structures:
(let ([s1 (make-semaphore)])
(define t1
(thread (lambda ()
(semaphore-wait s1)
(semaphore-post s1))))
(let loop ()
(sleep)
(semaphore-post s1)
(semaphore-wait s1)
(when (thread-running? t1)
(loop)))
(test #t string? "No starvation - good!"))
(let ([s1 (make-semaphore)]
[s2 (make-semaphore)])
(define t1
(thread (lambda ()
(semaphore-post (sync s1 s2)))))
(define t2
(thread (lambda ()
(semaphore-post (sync s1 s2)))))
(let loop ()
(sleep)
(semaphore-post s1)
(semaphore-wait s1)
(semaphore-post s2)
(semaphore-wait s2)
(when (or (thread-running? t1)
(thread-running? t2))
(loop)))
(test #t string? "No starvation - good!"))
;; ----------------------------------------
;; Breaks and dynamic-wind
(let ([s #f]
[p #f]
[/dev/null-for-err
(make-output-port #f always-evt (lambda (s start end ? ??) (- end start)) void void)]
[did-pre1 #f]
[did-pre2 #f]
[did-act1 #f]
[did-act2 #f]
[did-post1 #f]
[did-post2 #f]
[did-done #f]
[break-on (lambda () (break-enabled #t))]
[sw semaphore-wait])
(let ([mk-t
(lambda (init ;; how to start
;; functions that can capture the continuation:
capture-pre capture-act capture-post
;; whether to start the thread with breaks off (imperatively)
break-off?
;; things to do in pre, act, and post
pre-thunk act-thunk post-thunk
;; sema-wait or sema-wait/enable-break:
pre-semaphore-wait act-semaphore-wait post-semaphore-wait)
;; This reset function is called for a cptured continuation
;; to reset the effective arguments
(define (reset
-capture-pre -capture-act -capture-post
-break-off?
-pre-thunk -act-thunk -post-thunk
-pre-semaphore-wait -act-semaphore-wait -post-semaphore-wait)
(when -break-off?
(break-enabled #f))
(set! capture-pre -capture-pre)
(set! capture-act -capture-act)
(set! capture-post -capture-post)
(set! pre-thunk -pre-thunk)
(set! act-thunk -act-thunk)
(set! post-thunk -post-thunk)
(set! pre-semaphore-wait -pre-semaphore-wait)
(set! act-semaphore-wait -act-semaphore-wait)
(set! post-semaphore-wait -post-semaphore-wait))
;; initially, thread hasn't gotten anywhere:
(set! did-pre1 #f) (set! did-pre2 #f)
(set! did-act1 #f) (set! did-act2 #f)
(set! did-post1 #f) (set! did-post2 #f)
(set! did-done #f)
(thread
(lambda ()
(current-error-port /dev/null-for-err)
(when break-off?
(break-enabled #f))
(init ;; init function gets to decide whether to do the normal body:
(lambda ()
(printf "here ~s\n" (procedure? capture-pre))
(dynamic-wind
(lambda ()
(printf "here3 ~s\n" (procedure? capture-pre))
(capture-pre
reset
(lambda ()
(printf "here4\n")
(set! did-pre1 #t)
(semaphore-post p)
(pre-thunk)
(pre-semaphore-wait s)
(set! did-pre2 #t))))
(lambda ()
(printf "here2\n")
(capture-act
reset
(lambda ()
(set! did-act1 #t)
(semaphore-post p)
(act-thunk)
(act-semaphore-wait s)
(set! did-act2 #t))))
(lambda ()
(capture-post
reset
(lambda ()
(set! did-post1 #t)
(semaphore-post p)
(post-thunk)
(post-semaphore-wait s)
(set! did-post2 #t)))))
(set! did-done #t))))))])
;; `go' runs the tests, parameterized by when to break the other
;; thread and when it should take effect in the other thread
(define (go
mk-t* break-off?
pre-thunk act-thunk post-thunk
pre-semaphore-wait act-semaphore-wait post-semaphore-wait
try-pre-break
should-pre-break?
should-preact-break?
try-act-break
should-act-break?
try-post-break
should-post-break?
should-done-break?)
;; print the state for this test:
(test #t list? (list 'go
pre-thunk act-thunk post-thunk
pre-semaphore-wait act-semaphore-wait post-semaphore-wait
try-pre-break
should-pre-break?
should-preact-break?
try-act-break
should-act-break?
try-post-break
should-post-break?
should-done-break?))
;; create fresh semaphores
(set! s (make-semaphore))
(set! p (make-semaphore))
(printf "mk ~s\n" mk-t*)
;; create the thread
(let ([t (mk-t* break-off?
pre-thunk act-thunk post-thunk
pre-semaphore-wait act-semaphore-wait post-semaphore-wait)])
(semaphore-wait p)
(test #t 'pre1 did-pre1)
(try-pre-break t)
(semaphore-post s)
(if should-pre-break?
(begin
(thread-wait t)
(test #f 'pre2 did-pre2))
(if should-preact-break?
(begin
(semaphore-post s) ; for post
(thread-wait t)
(test #t 'pre2 did-pre2)
(test #f 'act1 did-act1))
(begin
(semaphore-wait p)
(test #t 'pre2 did-pre2)
(test #t 'act1 did-act1)
(try-act-break t)
(semaphore-post s)
(if should-act-break?
(begin
(semaphore-post s) ; for post
(thread-wait t)
(test #f 'act2 did-act2))
(begin
(semaphore-wait p)
(test #t 'act2 did-act2)
(test #t 'post1 did-post1)
(try-post-break t)
(semaphore-post s)
(if should-post-break?
(begin
(thread-wait t)
(test #f 'post2 did-post2))
(begin
(thread-wait t)
(test #t 'post2 did-post2)
(test (not should-done-break?) 'done did-done))))))))))
(for-each
(lambda (mk-t)
(for-each
(lambda (nada)
;; Basic checks --- dynamic-wind thunks don't explicitly enable breaks
(go mk-t #f nada nada nada sw sw sw void #f #f void #f void #f #f)
(go mk-t #f nada nada nada sw sw sw break-thread #f 'pre-act void #f void #f #f)
(go mk-t #f nada nada nada sw sw sw void #f #f break-thread 'act void #f #f)
(go mk-t #f nada nada nada sw sw sw void #f #f void #f break-thread #f 'done)
;; All dynamic-wind thunks enable breaks
(map (lambda (break-on sw)
(go mk-t #f break-on break-on break-on sw sw sw void #f #f void #f void #f #f)
(go mk-t #f break-on break-on break-on sw sw sw break-thread 'pre #f void #f void #f #f)
(go mk-t #f break-on break-on break-on sw sw sw void #f #f break-thread 'act void #f #f)
(go mk-t #f break-on break-on break-on sw sw sw void #f #f void #f break-thread 'post #f))
(list break-on void)
(list sw semaphore-wait/enable-break))
;; Enable break in pre or act shouldn't affect post
(go mk-t #f break-on nada nada sw sw sw void #f #f void #f break-thread #f 'done)
(go mk-t #f nada break-on nada sw sw sw void #f #f void #f break-thread #f 'done)
;; Enable break in pre shouldn't affect act/done
(go mk-t #t break-on nada nada sw sw sw void #f #f break-thread #f void #f #f)
(go mk-t #t break-on nada nada sw sw sw void #f #f void #f break-thread #f #f))
(list void sleep)))
;; We'll make threads in three modes: normal, restore a continuation into pre,
;; and restore a continuation into act
(let* ([no-capture (lambda (reset body) (body))]
[plain-mk-t (lambda args
(apply mk-t
(lambda (f) (f))
no-capture no-capture no-capture
args))]
[mk-capturing (lambda (which)
(let* ([k+reset #f]
[capture (lambda (reset body)
(let/cc k
(set! k+reset (cons k reset)))
(body))])
;; Grab a continuation for the dyn-wind's pre/act/post
(go (lambda args
(printf "here???\n")
(printf "??? ~s\n" k+reset)
(printf "??? ~s\n" capture)
(apply mk-t
(lambda (f) (f))
(if (eq? which 'pre) capture no-capture)
(if (eq? which 'act) capture no-capture)
(if (eq? which 'post) capture no-capture)
args))
#f void void void sw sw sw void #f #f void #f void #f #f)
(lambda args
(apply mk-t
(lambda (f)
;; First, reset the arguments that are in the continuation's
;; state
(apply (cdr k+reset) no-capture no-capture no-capture args)
;; Now restore the continuation
((car k+reset)))
no-capture no-capture no-capture
args))))])
(list plain-mk-t
(mk-capturing 'pre)
(mk-capturing 'act))))))
;; ----------------------------------------
;; Check wrap-evt result superceded by internally
;; installed constant (i.e., the input port):
(let ([p (make-input-port
'test
(lambda (bstr) never-evt)
(lambda (bstr skip-count progress-evt)
(wrap-evt always-evt (lambda (_) 17)))
void)])
;; Make sure we don't get 17
(test p sync p))
;; ----------------------------------------
(report-errs)