Bug #332002 “SEMAPHORE-MULTIPLE-WAITERS failure” : Bugs : SBCL

Revision history for this message

Gábor Melis (melisgl) wrote on 2009-02-20:

#1

Further info from Bob:

The Linux kernel version is 2.6.18.5. I believe it is a regression for me
and that SBCL 1.0.24.44 passes the test. Any suggestions for ways to debug
this?

Revision history for this message

Gábor Melis (melisgl) wrote on 2009-02-20:

#2

semaphore-test.lisp Edit (2.8 KiB, text/plain)

Could you please run the attached file and report the output? Also include the backtrace from the debugger, if any.

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Gábor Melis (melisgl) wrote on 2009-02-20:

#3

Oh, please change the timeout in the above code from 0.1 to 10.

Revision history for this message

Robert Brown (robert-brown) wrote on 2009-02-20:

#4

Download full text (33.1 KiB)

I changed the timeout to 10 and changed backtrace to sb-debug:backtrace.

paradicsom <11> cat semaphore-test.lisp
(defparameter *count* 0)

(let ((semaphore (sb-thread:make-semaphore :name "test sem")))
  (labels
      ((make-readers (n i)
         (values
          (loop for r from 0 below n
                collect
                (sb-thread:make-thread
                 (lambda ()
                   (let ((sem semaphore)
                         (*count* 0))
                     (dotimes (s i)
                       (incf *count*)
                       (sb-thread:wait-on-semaphore sem))))
                 :name (format nil "reader ~S" r)))
          (* n i)))
       (make-writers (n readers i)
         (let ((j (* readers i)))
           (multiple-value-bind (k rem) (truncate j n)
             (values
              (let ((writers
                     (loop for w from 0 below n
                           collect
                           (sb-thread:make-thread
                            (lambda ()
                              (let ((sem semaphore)
                                    (*count* 0))
                                (dotimes (s k)
                                  (incf *count*)
                                  (sb-thread:signal-semaphore sem))))
                            :name (format nil "writer ~S" w)))))
                (assert (zerop rem))
                writers)
              (+ rem (* n k))))))
       (test (r w n)
         (format *debug-io* "TEST ~S ~S ~S ~S~%" r w n (get-internal-real-time))
         (force-output t)
         (multiple-value-bind (readers x) (make-readers r n)
           (assert (= (length readers) r))
           (multiple-value-bind (writers y) (make-writers w r n)
             (assert (= (length writers) w))
             (assert (= x y))
             (handler-case
                 (sb-ext:with-timeout 10.0
                   (mapc #'sb-thread:join-thread writers)
                   (mapc #'sb-thread:join-thread readers))
               (sb-ext:timeout ()
                 (mapc (lambda (thread)
                         (format *debug-io* "BACKTRACE FOR ~A~%" thread)
                         (handler-case
                             (sb-thread:interrupt-thread
                              thread
                              (lambda ()
                                (format *debug-io* "Count=~S~%" *count*)
                                (sb-debug:backtrace)))
                           (sb-thread:interrupt-thread-error (c)
                             (declare (ignore c))
                             (format *debug-io*
                                     "Thread exited in the meantime ...~%")))
                         (sleep 0.1))
                       (append readers writers)))))
           (assert (zerop (sb-thread:semaphore-count semaphore)))
           (values))))
    (test 1 1 100)
    (test 2 2 10000)
    (test 4 2 10000)
    (test 4 2 10000)
    (test 10 10 10000)
    (test 10 1 10000)))

paradicsom <12> sbcl
This is SBCL 1.0.25.55, an implementation of ANSI Common Lisp.
More information about SBCL is available at <http://www.sbcl.org/>.

SBCL is free software, provided as is, with...

I changed the timeout to 10 and changed backtrace to sb-debug:backtrace.

paradicsom <11>  cat semaphore-test.lisp
(defparameter *count* 0)

(let ((semaphore (sb-thread:make-semaphore :name "test sem")))
  (labels
      ((make-readers (n i)
         (values
          (loop for r from 0 below n
                collect
                (sb-thread:make-thread
                 (lambda ()
                   (let ((sem semaphore)
                         (*count* 0))
                     (dotimes (s i)
                       (incf *count*)
                       (sb-thread:wait-on-semaphore sem))))
                 :name (format nil "reader ~S" r)))
          (* n i)))
       (make-writers (n readers i)
         (let ((j (* readers i)))
           (multiple-value-bind (k rem) (truncate j n)
             (values
              (let ((writers
                     (loop for w from 0 below n
                           collect
                           (sb-thread:make-thread
                            (lambda ()
                              (let ((sem semaphore)
                                    (*count* 0))
                                (dotimes (s k)
                                  (incf *count*)
                                  (sb-thread:signal-semaphore sem))))
                            :name (format nil "writer ~S" w)))))
                (assert (zerop rem))
                writers)
              (+ rem (* n k))))))
       (test (r w n)
         (format *debug-io* "TEST ~S ~S ~S ~S~%" r w n (get-internal-real-time))
         (force-output t)
         (multiple-value-bind (readers x) (make-readers r n)
           (assert (= (length readers) r))
           (multiple-value-bind (writers y) (make-writers w r n)
             (assert (= (length writers) w))
             (assert (= x y))
             (handler-case
                 (sb-ext:with-timeout 10.0
                   (mapc #'sb-thread:join-thread writers)
                   (mapc #'sb-thread:join-thread readers))
               (sb-ext:timeout ()
                 (mapc (lambda (thread)
                         (format *debug-io* "BACKTRACE FOR ~A~%" thread)
                         (handler-case
                             (sb-thread:interrupt-thread
                              thread
                              (lambda ()
                                (format *debug-io* "Count=~S~%" *count*)
                                (sb-debug:backtrace)))
                           (sb-thread:interrupt-thread-error (c)
                             (declare (ignore c))
                             (format *debug-io*
                                     "Thread exited in the meantime ...~%")))
                         (sleep 0.1))
                       (append readers writers)))))
           (assert (zerop (sb-thread:semaphore-count semaphore)))
           (values))))
    (test 1 1 100)
    (test 2 2 10000)
    (test 4 2 10000)
    (test 4 2 10000)
    (test 10 10 10000)
    (test 10 1 10000)))

paradicsom <12>  sbcl
This is SBCL 1.0.25.55, an implementation of ANSI Common Lisp.
More information about SBCL is available at <http://www.sbcl.org/>.

SBCL is free software, provided as is, with absolutely no warranty.
It is mostly in the public domain; some portions are provided under
BSD-style licenses.  See the CREDITS and COPYING files in the
distribution for more information.
* (compile-file "semaphore-test.lisp")

; compiling file "/home/brown/semaphore-test.lisp" (written 20 FEB 2009 10:46:03 AM):
; compiling (DEFPARAMETER *COUNT* ...)
; compiling (LET (#) ...)
; file: /home/brown/semaphore-test.lisp
; in: LET ((SEMAPHORE (SB-THREAD:MAKE-SEMAPHORE :NAME "test sem")))
;     #'SB-THREAD:JOIN-THREAD
;
; note: deleting unreachable code

;     (MAPC #'SB-THREAD:JOIN-THREAD BOB::WRITERS)
; --> LET LET
; ==>
;   BOB::WRITERS
;
; note: deleting unreachable code

;     #'SB-THREAD:JOIN-THREAD
;
; note: deleting unreachable code

;     (MAPC #'SB-THREAD:JOIN-THREAD BOB::READERS)
; --> LET LET
; ==>
;   BOB::READERS
;
; note: deleting unreachable code
;
; compilation unit finished
;   printed 4 notes

; /home/brown/semaphore-test.fasl written
; compilation finished in 0:00:00.148
#P"/home/brown/semaphore-test.fasl"
NIL
NIL
* (load "semaphore-test.fasl")
TEST 1 1 100 12935
TEST 2 2 10000 12937
TEST 4 2 10000 12979
TEST 4 2 10000 13448
TEST 10 10 10000 13741
TEST 10 1 10000 14859
BACKTRACE FOR #<THREAD "reader 0" RUNNING {1002F69BA1}>
Count=2890
0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {1002F62259}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE
    1152921504606846975
    #<SYNONYM-STREAM :SYMBOL *TERMINAL-IO* {10001D4551}>)
2: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITH-SYSTEM-MUTEX-THUNK]1011))
3: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17]27))
4: ((FLET #:WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17))
5: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAD35FC99}>)
6: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAD35FC99}>)[:EXTERNAL]
7: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAD3601D0)
    #.(SB-SYS:INT-SAP #X2AAAAD3600A0))
8: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAD3601D0)
    #.(SB-SYS:INT-SAP #X2AAAAD3600A0))[:OPTIONAL]
9: ((FLET SB-UNIX::RUN-HANDLER))[:EXTERNAL]
10: ("foreign function: #x41F993")
11: ("foreign function: #x40BABE")
12: ("foreign function: #x412385")
13: ("foreign function: #x41254F")
14: ("bogus stack frame")
15: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CONDITION-WAIT]356))
16: (SB-THREAD:CONDITION-WAIT
     #S(SB-THREAD:WAITQUEUE
        :NAME NIL
        :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {1002F74371}>)
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0))[:EXTERNAL]
17: ((FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK))
18: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS]303))
19: (SB-THREAD::CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS
     #<CLOSURE (FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK) {2AAAAD3608A9}>
     #S(SB-THREAD:MUTEX
        :NAME NIL
        :%OWNER #<SB-THREAD:THREAD "writer 0" RUNNING {1002F74371}>
        :STATE 2))
20: (SB-THREAD:WAIT-ON-SEMAPHORE
     #S(SB-THREAD:SEMAPHORE
        :NAME "test sem"
        :%COUNT 1127
        :WAITCOUNT 8
        :MUTEX #S(SB-THREAD:MUTEX
                  :NAME NIL
                  :%OWNER #<SB-THREAD:THREAD "writer 0" RUNNING {1002F74371}>
                  :STATE 0)
        :QUEUE #S(SB-THREAD:WAITQUEUE
                  :NAME NIL
                  :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {1002F74371}>)))
21: ((LAMBDA ()))
22: ((FLET #:WITHOUT-INTERRUPTS-BODY-[G844]850))
23: ((FLET SB-THREAD::WITH-MUTEX-THUNK))
24: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-MUTEX]446))
25: (SB-THREAD::CALL-WITH-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-MUTEX-THUNK) {2AAAAD360FD9}>
     #S(SB-THREAD:MUTEX
        :NAME "thread result lock"
        :%OWNER #<SB-THREAD:THREAD "reader 0" RUNNING {1002F69BA1}>
        :STATE 1)
     #<SB-THREAD:THREAD "reader 0" RUNNING {1002F69BA1}>
     T)
26: ((LAMBDA ()))
27: ("foreign function: #x41F993")
28: ("foreign function: #x4170F3")
BACKTRACE FOR #<THREAD "reader 1" RUNNING {1002F69F81}>
Count=2866
0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {1002FC9FC9}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE
    1152921504606846975
    #<SYNONYM-STREAM :SYMBOL *TERMINAL-IO* {10001D4551}>)
2: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITH-SYSTEM-MUTEX-THUNK]1011))
3: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17]27))
4: ((FLET #:WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17))
5: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAD7AAC99}>)
6: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAD7AAC99}>)[:EXTERNAL]
7: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAD7AB1D0)
    #.(SB-SYS:INT-SAP #X2AAAAD7AB0A0))
8: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAD7AB1D0)
    #.(SB-SYS:INT-SAP #X2AAAAD7AB0A0))[:OPTIONAL]
9: ((FLET SB-UNIX::RUN-HANDLER))[:EXTERNAL]
10: ("foreign function: #x41F993")
11: ("foreign function: #x40BABE")
12: ("foreign function: #x412385")
13: ("foreign function: #x41254F")
14: ("bogus stack frame")
15: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CONDITION-WAIT]356))
16: (SB-THREAD:CONDITION-WAIT
     #S(SB-THREAD:WAITQUEUE
        :NAME NIL
        :DATA #<SB-THREAD:THREAD "reader 2" RUNNING {1002F6A431}>)
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0))[:EXTERNAL]
17: ((FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK))
18: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS]303))
19: (SB-THREAD::CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS
     #<CLOSURE (FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK) {2AAAAD7AB8A9}>
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0))
20: (SB-THREAD:WAIT-ON-SEMAPHORE
     #S(SB-THREAD:SEMAPHORE
        :NAME "test sem"
        :%COUNT 0
        :WAITCOUNT 10
        :MUTEX #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0)
        :QUEUE #S(SB-THREAD:WAITQUEUE
                  :NAME NIL
                  :DATA #<SB-THREAD:THREAD "reader 2" RUNNING {1002F6A431}>)))
21: ((LAMBDA ()))
22: ((FLET #:WITHOUT-INTERRUPTS-BODY-[G844]850))
23: ((FLET SB-THREAD::WITH-MUTEX-THUNK))
24: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-MUTEX]446))
25: (SB-THREAD::CALL-WITH-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-MUTEX-THUNK) {2AAAAD7ABFD9}>
     #S(SB-THREAD:MUTEX
        :NAME "thread result lock"
        :%OWNER #<SB-THREAD:THREAD "reader 1" RUNNING {1002F69F81}>
        :STATE 1)
     #<SB-THREAD:THREAD "reader 1" RUNNING {1002F69F81}>
     T)
26: ((LAMBDA ()))
27: ("foreign function: #x41F993")
28: ("foreign function: #x4170F3")
BACKTRACE FOR #<THREAD "reader 2" RUNNING {1002F6A431}>
Count=3415
0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {1002FF5E59}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE
    1152921504606846975
    #<SYNONYM-STREAM :SYMBOL *TERMINAL-IO* {10001D4551}>)
2: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITH-SYSTEM-MUTEX-THUNK]1011))
3: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17]27))
4: ((FLET #:WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17))
5: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAADBF5C99}>)
6: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAADBF5C99}>)[:EXTERNAL]
7: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAADBF61D0)
    #.(SB-SYS:INT-SAP #X2AAAADBF60A0))
8: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAADBF61D0)
    #.(SB-SYS:INT-SAP #X2AAAADBF60A0))[:OPTIONAL]
9: ((FLET SB-UNIX::RUN-HANDLER))[:EXTERNAL]
10: ("foreign function: #x41F993")
11: ("foreign function: #x40BABE")
12: ("foreign function: #x412385")
13: ("foreign function: #x41254F")
14: ("bogus stack frame")
15: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CONDITION-WAIT]356))
16: (SB-THREAD:CONDITION-WAIT
     #S(SB-THREAD:WAITQUEUE
        :NAME NIL
        :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {1002F74371}>)
     #S(SB-THREAD:MUTEX
        :NAME NIL
        :%OWNER #<SB-THREAD:THREAD "writer 0" RUNNING {1002F74371}>
        :STATE 0))[:EXTERNAL]
17: ((FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK))
18: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS]303))
19: (SB-THREAD::CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS
     #<CLOSURE (FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK) {2AAAADBF68A9}>
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0))
20: (SB-THREAD:WAIT-ON-SEMAPHORE
     #S(SB-THREAD:SEMAPHORE
        :NAME "test sem"
        :%COUNT 0
        :WAITCOUNT 10
        :MUTEX #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0)
        :QUEUE #S(SB-THREAD:WAITQUEUE
                  :NAME NIL
                  :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {1002F74371}>)))
21: ((LAMBDA ()))
22: ((FLET #:WITHOUT-INTERRUPTS-BODY-[G844]850))
23: ((FLET SB-THREAD::WITH-MUTEX-THUNK))
24: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-MUTEX]446))
25: (SB-THREAD::CALL-WITH-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-MUTEX-THUNK) {2AAAADBF6FD9}>
     #S(SB-THREAD:MUTEX
        :NAME "thread result lock"
        :%OWNER #<SB-THREAD:THREAD "reader 2" RUNNING {1002F6A431}>
        :STATE 1)
     #<SB-THREAD:THREAD "reader 2" RUNNING {1002F6A431}>
     T)
26: ((LAMBDA ()))
27: ("foreign function: #x41F993")
28: ("foreign function: #x4170F3")
BACKTRACE FOR #<THREAD "reader 3" RUNNING {1002F6A811}>
Count=4101
0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {10032EBF69}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE
    1152921504606846975
    #<SYNONYM-STREAM :SYMBOL *TERMINAL-IO* {10001D4551}>)
2: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITH-SYSTEM-MUTEX-THUNK]1011))
3: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17]27))
4: ((FLET #:WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17))
5: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAE040C99}>)
6: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAE040C99}>)[:EXTERNAL]
7: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAE0411D0)
    #.(SB-SYS:INT-SAP #X2AAAAE0410A0))
8: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAE0411D0)
    #.(SB-SYS:INT-SAP #X2AAAAE0410A0))[:OPTIONAL]
9: ((FLET SB-UNIX::RUN-HANDLER))[:EXTERNAL]
10: ("foreign function: #x41F993")
11: ("foreign function: #x40BABE")
12: ("foreign function: #x412385")
13: ("foreign function: #x41254F")
14: ("bogus stack frame")
15: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CONDITION-WAIT]356))
16: (SB-THREAD:CONDITION-WAIT
     #S(SB-THREAD:WAITQUEUE
        :NAME NIL
        :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>)
     #S(SB-THREAD:MUTEX
        :NAME NIL
        :%OWNER #<SB-THREAD:THREAD "reader 5" RUNNING {1003278171}>
        :STATE 2))[:EXTERNAL]
17: ((FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK))
18: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS]303))
19: (SB-THREAD::CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS
     #<CLOSURE (FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK) {2AAAAE0418A9}>
     #S(SB-THREAD:MUTEX
        :NAME NIL
        :%OWNER #<SB-THREAD:THREAD "reader 5" RUNNING {1003278171}>
        :STATE 2))
20: (SB-THREAD:WAIT-ON-SEMAPHORE
     #S(SB-THREAD:SEMAPHORE
        :NAME "test sem"
        :%COUNT 0
        :WAITCOUNT 9
        :MUTEX #S(SB-THREAD:MUTEX
                  :NAME NIL
                  :%OWNER #<SB-THREAD:THREAD "reader 5" RUNNING {1003278171}>
                  :STATE 2)
        :QUEUE #S(SB-THREAD:WAITQUEUE
                  :NAME NIL
                  :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>)))
21: ((LAMBDA ()))
22: ((FLET #:WITHOUT-INTERRUPTS-BODY-[G844]850))
23: ((FLET SB-THREAD::WITH-MUTEX-THUNK))
24: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-MUTEX]446))
25: (SB-THREAD::CALL-WITH-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-MUTEX-THUNK) {2AAAAE041FD9}>
     #S(SB-THREAD:MUTEX
        :NAME "thread result lock"
        :%OWNER #<SB-THREAD:THREAD "reader 3" RUNNING {1003273951}>
        :STATE 1)
     #<SB-THREAD:THREAD "reader 3" RUNNING {1003273951}>
     T)
26: ((LAMBDA ()))
27: ("foreign function: #x41F993")
28: ("foreign function: #x4170F3")
BACKTRACE FOR #<THREAD "reader 4" RUNNING {1003273D31}>
Count=5834
0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {1003314E59}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE
    1152921504606846975
    #<SYNONYM-STREAM :SYMBOL *TERMINAL-IO* {10001D4551}>)
2: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITH-SYSTEM-MUTEX-THUNK]1011))
3: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17]27))
4: ((FLET #:WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17))
5: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAE8D5C99}>)
6: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAE8D5C99}>)[:EXTERNAL]
7: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAE8D61D0)
    #.(SB-SYS:INT-SAP #X2AAAAE8D60A0))
8: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAE8D61D0)
    #.(SB-SYS:INT-SAP #X2AAAAE8D60A0))[:OPTIONAL]
9: ((FLET SB-UNIX::RUN-HANDLER))[:EXTERNAL]
10: ("foreign function: #x41F993")
11: ("foreign function: #x40BABE")
12: ("foreign function: #x412385")
13: ("foreign function: #x41254F")
14: ("bogus stack frame")
15: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CONDITION-WAIT]356))
16: (SB-THREAD:CONDITION-WAIT
     #S(SB-THREAD:WAITQUEUE
        :NAME NIL
        :DATA #<SB-THREAD:THREAD "reader 8" RUNNING {1003278D11}>)
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0))[:EXTERNAL]
17: ((FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK))
18: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS]303))
19: (SB-THREAD::CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS
     #<CLOSURE (FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK) {2AAAAE8D68A9}>
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 2))
20: (SB-THREAD:WAIT-ON-SEMAPHORE
     #S(SB-THREAD:SEMAPHORE
        :NAME "test sem"
        :%COUNT 8794
        :WAITCOUNT 1
        :MUTEX #S(SB-THREAD:MUTEX
                  :NAME NIL
                  :%OWNER #<SB-THREAD:THREAD "reader 0" RUNNING {1003272CC1}>
                  :STATE 0)
        :QUEUE #S(SB-THREAD:WAITQUEUE
                  :NAME NIL
                  :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>)))
21: ((LAMBDA ()))
22: ((FLET #:WITHOUT-INTERRUPTS-BODY-[G844]850))
23: ((FLET SB-THREAD::WITH-MUTEX-THUNK))
24: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-MUTEX]446))
25: (SB-THREAD::CALL-WITH-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-MUTEX-THUNK) {2AAAAE8D6FD9}>
     #S(SB-THREAD:MUTEX
        :NAME "thread result lock"
        :%OWNER #<SB-THREAD:THREAD "reader 4" RUNNING {1003273D31}>
        :STATE 1)
     #<SB-THREAD:THREAD "reader 4" RUNNING {1003273D31}>
     T)
26: ((LAMBDA ()))
27: ("foreign function: #x41F993")
28: ("foreign function: #x4170F3")
BACKTRACE FOR #<THREAD "reader 5" RUNNING {1003278171}>
BACKTRACE FOR #<THREAD "reader 5" RUNNING {1003278171}>
Count=6865
0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {10027397D9}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE
    1152921504606846975
    #<SYNONYM-STREAM :SYMBOL *TERMINAL-IO* {10001D4551}>)
2: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITH-SYSTEM-MUTEX-THUNK]1011))
3: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17]27))
4: ((FLET #:WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17))
5: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAED20A49}>)
6: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAED20A49}>)[:EXTERNAL]
7: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAEF6D010)
    #.(SB-SYS:INT-SAP #X2AAAAED210D0))
8: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAEF6D010)
    #.(SB-SYS:INT-SAP #X2AAAAED210D0))[:OPTIONAL]
9: ((FLET SB-UNIX::RUN-HANDLER))[:EXTERNAL]
10: ("foreign function: #x41F993")
11: ("foreign function: #x40BABE")
12: ("foreign function: #x412385")
13: ("foreign function: #x411B78")
14: ("foreign function: #x411F76")
15: ("foreign function: #x40FD4B")
16: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CONDITION-WAIT]356))
17: (SB-THREAD:CONDITION-WAIT
     #S(SB-THREAD:WAITQUEUE
        :NAME NIL
        :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>)
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 1))[:EXTERNAL]
18: ((FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK))
19: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS]303))
20: (SB-THREAD::CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS
     #<CLOSURE (FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK) {2AAAAED218A9}>
     #S(SB-THREAD:MUTEX
        :NAME NIL
        :%OWNER #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>
        :STATE 0))
21: (SB-THREAD:WAIT-ON-SEMAPHORE
     #S(SB-THREAD:SEMAPHORE
        :NAME "test sem"
        :%COUNT 826
        :WAITCOUNT 6
        :MUTEX #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0)
        :QUEUE #S(SB-THREAD:WAITQUEUE
                  :NAME NIL
                  :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>)))
22: ((LAMBDA ()))
23: ((FLET #:WITHOUT-INTERRUPTS-BODY-[G844]850))
24: ((FLET SB-THREAD::WITH-MUTEX-THUNK))
25: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-MUTEX]446))
26: (SB-THREAD::CALL-WITH-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-MUTEX-THUNK) {2AAAAED21FD9}>
     #S(SB-THREAD:MUTEX
        :NAME "thread result lock"
        :%OWNER #<SB-THREAD:THREAD "reader 5" RUNNING {1003278171}>
        :STATE 1)
     #<SB-THREAD:THREAD "reader 5" RUNNING {1003278171}>
     T)
27: ((LAMBDA ()))
28: ("foreign function: #x41F993")
29: ("foreign function: #x4170F3")
BACKTRACE FOR #<THREAD "reader 6" RUNNING {1003278551}>
Count=9343
0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {1002778599}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE
    1152921504606846975
    #<SYNONYM-STREAM :SYMBOL *TERMINAL-IO* {10001D4551}>)
2: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITH-SYSTEM-MUTEX-THUNK]1011))
3: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17]27))
4: ((FLET #:WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17))
5: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAF16BA49}>)
6: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAF16BA49}>)[:EXTERNAL]
7: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAF3B8010)
    #.(SB-SYS:INT-SAP #X2AAAAF16C0D0))
8: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAF3B8010)
    #.(SB-SYS:INT-SAP #X2AAAAF16C0D0))[:OPTIONAL]
9: ((FLET SB-UNIX::RUN-HANDLER))[:EXTERNAL]
10: ("foreign function: #x41F993")
11: ("foreign function: #x40BABE")
12: ("foreign function: #x412385")
13: ("foreign function: #x411B78")
14: ("foreign function: #x411F76")
15: ("foreign function: #x40FD4B")
16: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CONDITION-WAIT]356))
17: (SB-THREAD:CONDITION-WAIT
     #S(SB-THREAD:WAITQUEUE
        :NAME NIL
        :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>)
     #S(SB-THREAD:MUTEX
        :NAME NIL
        :%OWNER #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>
        :STATE 1))[:EXTERNAL]
18: ((FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK))
19: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS]303))
20: (SB-THREAD::CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS
     #<CLOSURE (FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK) {2AAAAF16C8A9}>
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0))
21: (SB-THREAD:WAIT-ON-SEMAPHORE
     #S(SB-THREAD:SEMAPHORE
        :NAME "test sem"
        :%COUNT 32
        :WAITCOUNT 9
        :MUTEX #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0)
        :QUEUE #S(SB-THREAD:WAITQUEUE
                  :NAME NIL
                  :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>)))
22: ((LAMBDA ()))
23: ((FLET #:WITHOUT-INTERRUPTS-BODY-[G844]850))
24: ((FLET SB-THREAD::WITH-MUTEX-THUNK))
25: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-MUTEX]446))
26: (SB-THREAD::CALL-WITH-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-MUTEX-THUNK) {2AAAAF16CFD9}>
     #S(SB-THREAD:MUTEX
        :NAME "thread result lock"
        :%OWNER #<SB-THREAD:THREAD "reader 6" RUNNING {1003278551}>
        :STATE 1)
     #<SB-THREAD:THREAD "reader 6" RUNNING {1003278551}>
     T)
27: ((LAMBDA ()))
28: ("foreign function: #x41F993")
29: ("foreign function: #x4170F3")
BACKTRACE FOR #<THREAD "reader 7" RUNNING {1003278931}>
Count=8234
0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {10027B7259}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE
    1152921504606846975
    #<SYNONYM-STREAM :SYMBOL *TERMINAL-IO* {10001D4551}>)
2: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITH-SYSTEM-MUTEX-THUNK]1011))
3: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17]27))
4: ((FLET #:WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17))
5: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAF5B6A49}>)
6: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAF5B6A49}>)[:EXTERNAL]
7: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAF803010)
    #.(SB-SYS:INT-SAP #X2AAAAF5B70D0))
8: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAF803010)
    #.(SB-SYS:INT-SAP #X2AAAAF5B70D0))[:OPTIONAL]
9: ((FLET SB-UNIX::RUN-HANDLER))[:EXTERNAL]
10: ("foreign function: #x41F993")
11: ("foreign function: #x40BABE")
12: ("foreign function: #x412385")
13: ("foreign function: #x411B78")
14: ("foreign function: #x411F76")
15: ("foreign function: #x40FD4B")
16: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CONDITION-WAIT]356))
17: (SB-THREAD:CONDITION-WAIT
     #S(SB-THREAD:WAITQUEUE
        :NAME NIL
        :DATA #<SB-THREAD:THREAD "reader 6" RUNNING {1003278551}>)
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0))[:EXTERNAL]
18: ((FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK))
19: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS]303))
20: (SB-THREAD::CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS
     #<CLOSURE (FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK) {2AAAAF5B78A9}>
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0))
21: (SB-THREAD:WAIT-ON-SEMAPHORE
     #S(SB-THREAD:SEMAPHORE
        :NAME "test sem"
        :%COUNT 0
        :WAITCOUNT 10
        :MUTEX #S(SB-THREAD:MUTEX
                  :NAME NIL
                  :%OWNER #<SB-THREAD:THREAD "reader 6" RUNNING {1003278551}>
                  :STATE 1)
        :QUEUE #S(SB-THREAD:WAITQUEUE
                  :NAME NIL
                  :DATA #<SB-THREAD:THREAD "reader 6" RUNNING {1003278551}>)))
22: ((LAMBDA ()))
23: ((FLET #:WITHOUT-INTERRUPTS-BODY-[G844]850))
24: ((FLET SB-THREAD::WITH-MUTEX-THUNK))
25: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-MUTEX]446))
26: (SB-THREAD::CALL-WITH-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-MUTEX-THUNK) {2AAAAF5B7FD9}>
     #S(SB-THREAD:MUTEX
        :NAME "thread result lock"
        :%OWNER #<SB-THREAD:THREAD "reader 7" RUNNING {1003278931}>
        :STATE 1)
     #<SB-THREAD:THREAD "reader 7" RUNNING {1003278931}>
     T)
27: ((LAMBDA ()))
28: ("foreign function: #x41F993")
29: ("foreign function: #x4170F3")
BACKTRACE FOR #<THREAD "reader 8" RUNNING {1003278D11}>
Count=6374
0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {10027F55C9}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE
    1152921504606846975
    #<SYNONYM-STREAM :SYMBOL *TERMINAL-IO* {10001D4551}>)
2: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITH-SYSTEM-MUTEX-THUNK]1011))
3: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17]27))
4: ((FLET #:WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17))
5: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAFA01E59}>)
6: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAFA01E59}>)[:EXTERNAL]
7: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAFA02390)
    #.(SB-SYS:INT-SAP #X2AAAAFA02260))
8: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAFA02390)
    #.(SB-SYS:INT-SAP #X2AAAAFA02260))[:OPTIONAL]
9: ((FLET SB-UNIX::RUN-HANDLER))[:EXTERNAL]
10: ("foreign function: #x41F993")
11: ("foreign function: #x40BABE")
12: ("foreign function: #x412385")
13: ("foreign function: #x41254F")
14: ("bogus stack frame")
15: (SB-THREAD:GET-MUTEX
     #<unavailable argument>
     #<unavailable argument>
     #<unavailable argument>)
16: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS]303))
17: (SB-THREAD::CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS
     #<CLOSURE (FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK) {2AAAAFA028A9}>
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0))
18: (SB-THREAD:WAIT-ON-SEMAPHORE
     #S(SB-THREAD:SEMAPHORE
        :NAME "test sem"
        :%COUNT 0
        :WAITCOUNT 8
        :MUTEX #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0)
        :QUEUE #S(SB-THREAD:WAITQUEUE
                  :NAME NIL
                  :DATA #<SB-THREAD:THREAD "reader 4" RUNNING {1003273D31}>)))
19: ((LAMBDA ()))
20: ((FLET #:WITHOUT-INTERRUPTS-BODY-[G844]850))
21: ((FLET SB-THREAD::WITH-MUTEX-THUNK))
22: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-MUTEX]446))
23: (SB-THREAD::CALL-WITH-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-MUTEX-THUNK) {2AAAAFA02FD9}>
     #S(SB-THREAD:MUTEX
        :NAME "thread result lock"
        :%OWNER #<SB-THREAD:THREAD "reader 8" RUNNING {1003278D11}>
        :STATE 1)
     #<SB-THREAD:THREAD "reader 8" RUNNING {1003278D11}>
     T)
24: ((LAMBDA ()))
25: ("foreign function: #x41F993")
26: ("foreign function: #x4170F3")
BACKTRACE FOR #<THREAD "reader 9" RUNNING {100327D171}>
Count=7355
0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {1002822E59}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE
    1152921504606846975
    #<SYNONYM-STREAM :SYMBOL *TERMINAL-IO* {10001D4551}>)
2: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITH-SYSTEM-MUTEX-THUNK]1011))
3: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17]27))
4: ((FLET #:WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17))
5: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAFE4CE59}>)
6: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAAFE4CE59}>)[:EXTERNAL]
7: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAFE4D390)
    #.(SB-SYS:INT-SAP #X2AAAAFE4D260))
8: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAAFE4D390)
    #.(SB-SYS:INT-SAP #X2AAAAFE4D260))[:OPTIONAL]
9: ((FLET SB-UNIX::RUN-HANDLER))[:EXTERNAL]
10: ("foreign function: #x41F993")
11: ("foreign function: #x40BABE")
12: ("foreign function: #x412385")
13: ("foreign function: #x41254F")
14: ("bogus stack frame")
15: (SB-THREAD:GET-MUTEX
     #<unavailable argument>
     #<unavailable argument>
     #<unavailable argument>)
16: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS]303))
17: (SB-THREAD::CALL-WITH-SYSTEM-MUTEX/ALLOW-WITH-INTERRUPTS
     #<CLOSURE (FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK) {2AAAAFE4D8A9}>
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 1))
18: (SB-THREAD:WAIT-ON-SEMAPHORE
     #S(SB-THREAD:SEMAPHORE
        :NAME "test sem"
        :%COUNT 1
        :WAITCOUNT 9
        :MUTEX #S(SB-THREAD:MUTEX
                  :NAME NIL
                  :%OWNER #<SB-THREAD:THREAD "reader 4" RUNNING {1003273D31}>
                  :STATE 1)
        :QUEUE #S(SB-THREAD:WAITQUEUE
                  :NAME NIL
                  :DATA #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>)))
19: ((LAMBDA ()))
20: ((FLET #:WITHOUT-INTERRUPTS-BODY-[G844]850))
21: ((FLET SB-THREAD::WITH-MUTEX-THUNK))
22: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-MUTEX]446))
23: (SB-THREAD::CALL-WITH-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-MUTEX-THUNK) {2AAAAFE4DFD9}>
     #S(SB-THREAD:MUTEX
        :NAME "thread result lock"
        :%OWNER #<SB-THREAD:THREAD "reader 9" RUNNING {100327D171}>
        :STATE 1)
     #<SB-THREAD:THREAD "reader 9" RUNNING {100327D171}>
     T)
24: ((LAMBDA ()))
25: ("foreign function: #x41F993")
26: ("foreign function: #x4170F3")
BACKTRACE FOR #<THREAD "writer 0" RUNNING {100327D561}>
Count=81266
0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {1002866259}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE
    1152921504606846975
    #<SYNONYM-STREAM :SYMBOL *TERMINAL-IO* {10001D4551}>)
2: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITH-SYSTEM-MUTEX-THUNK]1011))
3: ((FLET #:WITHOUT-INTERRUPTS-BODY-[WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17]27))
4: ((FLET #:WITHOUT-INTERRUPTS-BODY-[INVOKE-INTERRUPTION]17))
5: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAB0297C89}>)
6: (SB-SYS:INVOKE-INTERRUPTION
    #<CLOSURE (FLET SB-UNIX::INTERRUPTION) {2AAAB0297C89}>)[:EXTERNAL]
7: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAB04E4010)
    #.(SB-SYS:INT-SAP #X2AAAB0298310))
8: ((FLET SB-UNIX::RUN-HANDLER)
    13
    #.(SB-SYS:INT-SAP #X2AAAB04E4010)
    #.(SB-SYS:INT-SAP #X2AAAB0298310))[:OPTIONAL]
9: ((FLET SB-UNIX::RUN-HANDLER))[:EXTERNAL]
10: ("foreign function: #x41F993")
11: ("foreign function: #x40BABE")
12: ("foreign function: #x412385")
13: ("foreign function: #x411B78")
14: ("foreign function: #x411F76")
15: ("foreign function: #x40FD4B")
16: ((FLET #:CLEANUP-FUN-[CALL-WITH-SYSTEM-MUTEX]257))[:CLEANUP]
17: (SB-THREAD::CALL-WITH-SYSTEM-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-SYSTEM-MUTEX-THUNK) {2AAAB02988E9}>
     #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0))
18: (SB-THREAD:SIGNAL-SEMAPHORE
     #S(SB-THREAD:SEMAPHORE
        :NAME "test sem"
        :%COUNT 0
        :WAITCOUNT 8
        :MUTEX #S(SB-THREAD:MUTEX :NAME NIL :%OWNER NIL :STATE 0)
        :QUEUE #S(SB-THREAD:WAITQUEUE
                  :NAME NIL
                  :DATA #<SB-THREAD:THREAD "reader 2" RUNNING {1003273571}>))
     1)
19: ((LAMBDA ()))
20: ((FLET #:WITHOUT-INTERRUPTS-BODY-[G844]850))
21: ((FLET SB-THREAD::WITH-MUTEX-THUNK))
22: ((FLET #:WITHOUT-INTERRUPTS-BODY-[CALL-WITH-MUTEX]446))
23: (SB-THREAD::CALL-WITH-MUTEX
     #<CLOSURE (FLET SB-THREAD::WITH-MUTEX-THUNK) {2AAAB0298FD9}>
     #S(SB-THREAD:MUTEX
        :NAME "thread result lock"
        :%OWNER #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>
        :STATE 2)
     #<SB-THREAD:THREAD "writer 0" RUNNING {100327D561}>
     T)
24: ((LAMBDA ()))
25: ("foreign function: #x41F993")
26: ("foreign function: #x4170F3")

T
* (load "semaphore-test.fasl")
TEST 1 1 100 47146
TEST 2 2 10000 47148
TEST 4 2 10000 47172
TEST 4 2 10000 47377
TEST 10 10 10000 47480
TEST 10 1 10000 48008

T
* (load "semaphore-test.fasl")
TEST 1 1 100 229995
TEST 2 2 10000 229997
TEST 4 2 10000 230106
TEST 4 2 10000 230260
TEST 10 10 10000 230578
TEST 10 1 10000 230892

T
*

Revision history for this message

Robert Brown (robert-brown) wrote on 2009-02-20:

#5

I ran the test code using sbcl 1.0.24.44. It consistently passes.
The failure rate with sbcl 1.0.25.55 is about 50 percent.

Revision history for this message

Gábor Melis (melisgl) wrote on 2009-02-23:

#6

It consistently passes for me.

However, I found a few related issues and made fixes available on the waitqueue branch [2] of my git tree [1].

The test that's added in the "less pessimal waitqueues" commit displays rather erratic behaviour on my system: it finishes in 2s or it hangs for a few seconds here and there and then continues. The strange thing is that it can affect the system to the point where X becomes unresponsive, and even switching between character based virtual terminals is impossible. Then it unwedges and life goes on. Is this similar behaviour to what you observe?

I suspect what I see is kernel issue, mine is 2.6.26. Reading [3] made me add the FUTEX_WAIT_PRIVATE, FUTEX_WAKE_PRIVATE flags to the relevant calls but they didn't help much, save for measurably reducing contention between mmap and futex.

Could you please test this branch? The last commit (the futex private one) may not work on your kernel, use the one before it.

[1] http://quotenil.com/git/sbcl.git
[2] http://quotenil.com/git/?p=sbcl.git;a=shortlog;h=waitqueue
[3] http://blogs.sun.com/roland/entry/real_time_java_and_futexes

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Robert Brown (robert-brown) wrote on 2009-02-25: Re: [Bug 332002] Re: SEMAPHORE-MULTIPLE-WAITERS failure

#7

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I just noticed your email. I'll give it a try later tonight if I have the time.

bob

==========

On Mon, Feb 23, 2009 at 10:20 AM, Gábor Melis <email address hidden> wrote:
> It consistently passes for me.
>
> However, I found a few related issues and made fixes available on the
> waitqueue branch [2] of my git tree [1].
>
> The test that's added in the "less pessimal waitqueues" commit displays
> rather erratic behaviour on my system: it finishes in 2s or it hangs for
> a few seconds here and there and then continues. The strange thing is
> that it can affect the system to the point where X becomes unresponsive,
> and even switching between character based virtual terminals is
> impossible. Then it unwedges and life goes on. Is this similar behaviour
> to what you observe?
>
> I suspect what I see is kernel issue, mine is 2.6.26. Reading [3] made
> me add the FUTEX_WAIT_PRIVATE, FUTEX_WAKE_PRIVATE flags to the relevant
> calls but they didn't help much, save for measurably reducing contention
> between mmap and futex.
>
> Could you please test this branch? The last commit (the futex private
> one) may not work on your kernel, use the one before it.
>
> [1] http://quotenil.com/git/sbcl.git
> [2] http://quotenil.com/git/?p=sbcl.git;a=shortlog;h=waitqueue
> [3] http://blogs.sun.com/roland/entry/real_time_java_and_futexes
>
> --
> SEMAPHORE-MULTIPLE-WAITERS failure
> https://bugs.launchpad.net/bugs/332002
> You received this bug notification because you are a direct subscriber
> of the bug.
>
> Status in Steel Bank Common Lisp: New
>
> Bug description:
> Reported by Robert Brown:
>
> I just compiled SBCL 1.0.25.55 and ran the tests. I'm getting a failure of
> test SEMAPHORE-MULTIPLE-WAITERS. My system is a 2 CPU dual core Opteron
> running Ubuntu Linux in 64-bit mode. I compiled the same SBCL version on my
> netbook, 32-bit Atom running Ubuntu 8.10 and same test passes.
>
> bob
>
> ====================
>
> paradicsom [51] sh ./run-tests.sh threads.pure.lisp
> /running tests on
> '/usr/local/google/local-brown/software/source-trees/sbcl/tests/../src/runtime/sbcl
> --core
> /usr/local/google/local-brown/software/source-trees/sbcl/tests/../output/sbcl.core
> --noinform --no-sysinit --no-userinit --noprint --disable-debugger'
> ; loading system definition from
> ;
> /usr/local/google/local-brown/software/source-trees/sbcl/contrib/sb-posix/sb-posix.asd
> ; into #<PACKAGE "ASDF0">
> ; loading system definition from
> ;
> /usr/local/google/local-brown/software/source-trees/sbcl/contrib/sb-grovel/sb-grovel.asd
> ; into #<PACKAGE "ASDF1">
> ; registering #<SYSTEM SB-GROVEL {1002FB15A1}> as SB-GROVEL
> ; registering #<SYSTEM SB-POSIX {1002F0A581}> as SB-POSIX
> ; registering #<SYSTEM SB-POSIX-TESTS {10031458F1}> as SB-POSIX-TESTS
> STYLE-WARNING: Couldn't grovel for SIGEMT (unknown to the C compiler).
> STYLE-WARNING: Couldn't grovel for S_IFWHT (unknown to the C compiler).
> STYLE-WARNING: Couldn't grovel for O_NOFOLLOW (unknown to the C compiler).
> STYLE-WARNING: Couldn't grovel for O_DIRECTORY (unknown to the C compiler).
> STYLE-WARNING: Couldn't grovel for O_DIRECT (unknown to the C compiler).
> STYLE-WARNING: Couldn't grovel for O_LARGEFILE (unknown...

SBCL

SEMAPHORE-MULTIPLE-WAITERS failure

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Changed in sbcl:
status:	New → Invalid