The Inbox: System-ael.488.mcz

A new version of System was added to project The Inbox:
http://source.squeak.org/inbox/System-ael.488.mcz

==================== Summary ====================

Name: System-ael.488
Author: ael
Time: 10 July 2012, 1:56:20.102 pm
UUID: 18e76459-4ed0-478c-b2b3-9d587d1f6b3d
Ancestors: System-eem.487

Tentative fix for 'tally is already running' error when profiling from ProcessBrowser.

=============== Diff against System-eem.487 ===============

Item was changed:
  ----- Method: MessageTally>>spyEvery:onProcess:forMilliseconds: (in category 'initialize-release') -----
  spyEvery: millisecs onProcess: aProcess forMilliseconds: msecDuration
  "Create a spy and spy on the given process at the specified rate."
  | myDelay time0 endTime observedProcess sem |
  (aProcess isKindOf: Process)
  ifFalse: [self error: 'spy needs a Process here'].
  self class: aProcess suspendedContext receiver class method: aProcess suspendedContext method.
  "set up the probe"
  observedProcess := aProcess.
  myDelay := Delay forMilliseconds: millisecs.
  time0 := Time millisecondClockValue.
  endTime := time0 + msecDuration.
  sem := Semaphore new.
  gcStats := SmalltalkImage current getVMParameters.
  Timer ifNotNil: [ self error: 'it seems a tally is already running' ].
  Timer := [
  [
  | startTime |
  startTime := Time millisecondClockValue.
  myDelay wait.
  self
  tally: Processor preemptedProcess suspendedContext
  in: (observedProcess == Processor preemptedProcess
  ifTrue: [ observedProcess ]
  ifFalse: [ nil ])
  "tally can be > 1 if ran a long primitive"
  by: (Time millisecondClockValue - startTime) // millisecs.
  startTime < endTime
  ] whileTrue.
  sem signal.
  ] newProcess.
  Timer priority: Processor timingPriority-1.
  "activate the probe and evaluate the block"
  Timer resume.
  "activate the probe and wait for it to finish"
  sem wait.
+ Timer ifNotNil: [
+ Timer terminate.
+ Timer := nil ].
  "Collect gc statistics"
  SmalltalkImage current getVMParameters keysAndValuesDo: [ :idx :gcVal |
  gcVal ifNotNil: [ gcStats at: idx put: (gcVal - (gcStats at: idx)) ] ].
  time := Time millisecondClockValue - time0!