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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /nsprpub/pr/tests/bug1test.c
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
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Add m-esr52 at 52.6.0
Diffstat (limited to 'nsprpub/pr/tests/bug1test.c')
-rw-r--r--nsprpub/pr/tests/bug1test.c225
1 files changed, 225 insertions, 0 deletions
diff --git a/nsprpub/pr/tests/bug1test.c b/nsprpub/pr/tests/bug1test.c
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+++ b/nsprpub/pr/tests/bug1test.c
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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+Attached is a test program that uses the nspr1 to demonstrate a bug
+under NT4.0. The fix has already been mentioned (add a ResetEvent just
+before leaving the critical section in _PR_CondWait in hwmon.c).
+*/
+
+#include "prthread.h"
+#include "prtypes.h"
+#include "prinit.h"
+#include "prmon.h"
+#include "prlog.h"
+
+typedef struct Arg_s
+{
+ PRInt32 a, b;
+} Arg_t;
+
+PRMonitor* gMonitor; // the monitor
+PRInt32 gReading; // number of read locks
+PRInt32 gWriteWaiting; // number of threads waiting for write lock
+PRInt32 gReadWaiting; // number of threads waiting for read lock
+
+PRInt32 gCounter; // a counter
+
+ // stats
+PRInt32 gReads; // number of successful reads
+PRInt32 gMaxReads; // max number of simultaneous reads
+PRInt32 gMaxWriteWaits; // max number of writes that waited for read
+PRInt32 gMaxReadWaits; // max number of reads that waited for write wait
+
+
+void spin (PRInt32 aDelay)
+{
+ PRInt32 index;
+ PRInt32 delay = aDelay * 1000;
+
+ PR_Sleep(0);
+
+ // randomize delay a bit
+ delay = (delay / 2) + (PRInt32)((float)delay *
+ ((float)rand () / (float)RAND_MAX));
+
+ for (index = 0; index < delay * 10; index++)
+ // consume a bunch of cpu cycles
+ ;
+ PR_Sleep(0);
+}
+
+void doWriteThread (void* arg)
+{
+ PRInt32 last;
+ Arg_t *args = (Arg_t*)arg;
+ PRInt32 aWorkDelay = args->a, aWaitDelay = args->b;
+ PR_Sleep(0);
+
+ while (1)
+ {
+ // -- enter write lock
+ PR_EnterMonitor (gMonitor);
+
+ if (0 < gReading) // wait for read locks to go away
+ {
+ PRIntervalTime fiveSecs = PR_SecondsToInterval(5);
+
+ gWriteWaiting++;
+ if (gWriteWaiting > gMaxWriteWaits) // stats
+ gMaxWriteWaits = gWriteWaiting;
+ while (0 < gReading)
+ PR_Wait (gMonitor, fiveSecs);
+ gWriteWaiting--;
+ }
+ // -- write lock entered
+
+ last = gCounter;
+ gCounter++;
+
+ spin (aWorkDelay);
+
+ PR_ASSERT (gCounter == (last + 1)); // test invariance
+
+ // -- exit write lock
+// if (0 < gReadWaiting) // notify waiting reads (do it anyway to show off the CondWait bug)
+ PR_NotifyAll (gMonitor);
+
+ PR_ExitMonitor (gMonitor);
+ // -- write lock exited
+
+ spin (aWaitDelay);
+ }
+}
+
+void doReadThread (void* arg)
+{
+ PRInt32 last;
+ Arg_t *args = (Arg_t*)arg;
+ PRInt32 aWorkDelay = args->a, aWaitDelay = args->b;
+ PR_Sleep(0);
+
+ while (1)
+ {
+ // -- enter read lock
+ PR_EnterMonitor (gMonitor);
+
+ if (0 < gWriteWaiting) // give up the monitor to waiting writes
+ {
+ PRIntervalTime fiveSecs = PR_SecondsToInterval(5);
+
+ gReadWaiting++;
+ if (gReadWaiting > gMaxReadWaits) // stats
+ gMaxReadWaits = gReadWaiting;
+ while (0 < gWriteWaiting)
+ PR_Wait (gMonitor, fiveSecs);
+ gReadWaiting--;
+ }
+
+ gReading++;
+
+ gReads++; // stats
+ if (gReading > gMaxReads) // stats
+ gMaxReads = gReading;
+
+ PR_ExitMonitor (gMonitor);
+ // -- read lock entered
+
+ last = gCounter;
+
+ spin (aWorkDelay);
+
+ PR_ASSERT (gCounter == last); // test invariance
+
+ // -- exit read lock
+ PR_EnterMonitor (gMonitor); // read unlock
+ gReading--;
+
+// if ((0 == gReading) && (0 < gWriteWaiting)) // notify waiting writes (do it anyway to show off the CondWait bug)
+ PR_NotifyAll (gMonitor);
+ PR_ExitMonitor (gMonitor);
+ // -- read lock exited
+
+ spin (aWaitDelay);
+ }
+}
+
+
+void fireThread (
+ char* aName, void (*aProc)(void *arg), Arg_t *aArg)
+{
+ PRThread *thread = PR_CreateThread(
+ PR_USER_THREAD, aProc, aArg, PR_PRIORITY_NORMAL,
+ PR_LOCAL_THREAD, PR_UNJOINABLE_THREAD, 0);
+}
+
+int pseudoMain (int argc, char** argv, char *pad)
+{
+ PRInt32 lastWriteCount = gCounter;
+ PRInt32 lastReadCount = gReads;
+ Arg_t a1 = {500, 250};
+ Arg_t a2 = {500, 500};
+ Arg_t a3 = {250, 500};
+ Arg_t a4 = {750, 250};
+ Arg_t a5 = {100, 750};
+ Arg_t a6 = {100, 500};
+ Arg_t a7 = {100, 750};
+
+ gMonitor = PR_NewMonitor ();
+
+ fireThread ("R1", doReadThread, &a1);
+ fireThread ("R2", doReadThread, &a2);
+ fireThread ("R3", doReadThread, &a3);
+ fireThread ("R4", doReadThread, &a4);
+
+ fireThread ("W1", doWriteThread, &a5);
+ fireThread ("W2", doWriteThread, &a6);
+ fireThread ("W3", doWriteThread, &a7);
+
+ fireThread ("R5", doReadThread, &a1);
+ fireThread ("R6", doReadThread, &a2);
+ fireThread ("R7", doReadThread, &a3);
+ fireThread ("R8", doReadThread, &a4);
+
+ fireThread ("W4", doWriteThread, &a5);
+ fireThread ("W5", doWriteThread, &a6);
+ fireThread ("W6", doWriteThread, &a7);
+
+ while (1)
+ {
+ PRInt32 writeCount, readCount;
+ PRIntervalTime fiveSecs = PR_SecondsToInterval(5);
+ PR_Sleep (fiveSecs); // get out of the way
+
+ // print some stats, not threadsafe, informative only
+ writeCount = gCounter;
+ readCount = gReads;
+ printf ("\ntick %d writes (+%d), %d reads (+%d) [max %d, %d, %d]",
+ writeCount, writeCount - lastWriteCount,
+ readCount, readCount - lastReadCount,
+ gMaxReads, gMaxWriteWaits, gMaxReadWaits);
+ lastWriteCount = writeCount;
+ lastReadCount = readCount;
+ gMaxReads = gMaxWriteWaits = gMaxReadWaits = 0;
+ }
+ return 0;
+}
+
+
+static void padStack (int argc, char** argv)
+{
+ char pad[512]; /* Work around bug in nspr on windoze */
+ pseudoMain (argc, argv, pad);
+}
+
+int main(int argc, char **argv)
+{
+ PR_Init(PR_USER_THREAD, PR_PRIORITY_NORMAL, 0);
+ PR_STDIO_INIT();
+ padStack (argc, argv);
+}
+
+
+/* bug1test.c */