michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /*
michael@0: ** File:            switch.cpp
michael@0: ** Description:     trying to time context switches
michael@0: */
michael@0: 
michael@0: #include "rccv.h"
michael@0: #include "rcinrval.h"
michael@0: #include "rclock.h"
michael@0: #include "rcthread.h"
michael@0: 
michael@0: #include <prio.h>
michael@0: #include <prlog.h>
michael@0: #include <prprf.h>
michael@0: #include <plerror.h>
michael@0: #include <plgetopt.h>
michael@0: 
michael@0: #include <stdlib.h>
michael@0: 
michael@0: #define INNER_LOOPS 100
michael@0: #define DEFAULT_LOOPS 100
michael@0: #define DEFAULT_THREADS 10
michael@0: 
michael@0: static PRFileDesc *debug_out = NULL;
michael@0: static PRBool debug_mode = PR_FALSE, verbosity = PR_FALSE, failed = PR_FALSE;
michael@0: 
michael@0: class Home: public RCCondition
michael@0: {
michael@0: public:
michael@0:     virtual ~Home();
michael@0:     Home(Home *link, RCLock* ml);
michael@0: 
michael@0: public:
michael@0:     Home *next;
michael@0:     RCLock* ml;
michael@0:     PRBool twiddle;
michael@0: };  /* Home */
michael@0: 
michael@0: Home::~Home() { }
michael@0: 
michael@0: Home::Home(Home *link, RCLock* lock): RCCondition(lock)
michael@0: {
michael@0:     ml = lock;
michael@0:     next = link;
michael@0:     twiddle = PR_FALSE;
michael@0: }  /* Home::Home */
michael@0: 
michael@0: class Shared: public Home, public RCThread
michael@0: {
michael@0: public:
michael@0:     Shared(RCThread::Scope scope, Home* link, RCLock* ml);
michael@0: 
michael@0: private:
michael@0:     ~Shared();
michael@0:     void RootFunction();
michael@0: };  /* Shared */
michael@0: 
michael@0: Shared::Shared(RCThread::Scope scope, Home* link, RCLock* lock):
michael@0:     Home(link, lock), RCThread(scope, RCThread::joinable) { }
michael@0: 
michael@0: Shared::~Shared() { }
michael@0: 
michael@0: void Shared::RootFunction()
michael@0: {
michael@0:     PRStatus status = PR_SUCCESS;
michael@0:     while (PR_SUCCESS == status)
michael@0:     {
michael@0:         RCEnter entry(ml);
michael@0:         while (twiddle && (PR_SUCCESS == status)) status = Wait();
michael@0: 		if (verbosity) PR_fprintf(debug_out, "+");
michael@0:         twiddle = PR_TRUE;
michael@0:         next->twiddle = PR_FALSE;
michael@0:         next->Notify();
michael@0:     }
michael@0: }  /* Shared::RootFunction */
michael@0: 
michael@0: static void Help(void)
michael@0: {
michael@0:     debug_out = PR_STDOUT;
michael@0: 
michael@0:     PR_fprintf(
michael@0: 		debug_out, "Usage: >./switch [-d] [-c n] [-t n] [-T n] [-G]\n");
michael@0:     PR_fprintf(
michael@0: 		debug_out, "-c n\tloops at thread level (default: %d)\n", DEFAULT_LOOPS);
michael@0:     PR_fprintf(
michael@0: 		debug_out, "-t n\tnumber of threads (default: %d)\n", DEFAULT_THREADS);
michael@0:     PR_fprintf(debug_out, "-d\tturn on debugging output (default: FALSE)\n");
michael@0:     PR_fprintf(debug_out, "-v\tturn on verbose output (default: FALSE)\n");
michael@0:     PR_fprintf(debug_out, "-G n\tglobal threads only (default: FALSE)\n");
michael@0:     PR_fprintf(debug_out, "-C n\tconcurrency setting (default: 1)\n");
michael@0: }  /* Help */
michael@0: 
michael@0: PRIntn main(PRIntn argc, char **argv)
michael@0: {
michael@0: 	PLOptStatus os;
michael@0:     PRStatus status;
michael@0:     PRBool help = PR_FALSE;
michael@0:     PRUintn concurrency = 1;
michael@0:     RCThread::Scope thread_scope = RCThread::local;
michael@0:     PRUintn thread_count, inner_count, loop_count, average;
michael@0:     PRUintn thread_limit = DEFAULT_THREADS, loop_limit = DEFAULT_LOOPS;
michael@0: 	PLOptState *opt = PL_CreateOptState(argc, argv, "hdvc:t:C:G");
michael@0: 	while (PL_OPT_EOL != (os = PL_GetNextOpt(opt)))
michael@0:     {
michael@0: 		if (PL_OPT_BAD == os) continue;
michael@0:         switch (opt->option)
michael@0:         {
michael@0:         case 'v':  /* verbose mode */
michael@0: 			verbosity = PR_TRUE;
michael@0:         case 'd':  /* debug mode */
michael@0: 			debug_mode = PR_TRUE;
michael@0:             break;
michael@0:         case 'c':  /* loop counter */
michael@0: 			loop_limit = atoi(opt->value);
michael@0:             break;
michael@0:         case 't':  /* thread limit */
michael@0: 			thread_limit = atoi(opt->value);
michael@0:             break;
michael@0:         case 'C':  /* Concurrency limit */
michael@0: 			concurrency = atoi(opt->value);
michael@0:             break;
michael@0:         case 'G':  /* global threads only */
michael@0: 			thread_scope = RCThread::global;
michael@0:             break;
michael@0:         case 'h':  /* help message */
michael@0: 			Help();
michael@0: 			help = PR_TRUE;
michael@0:             break;
michael@0:          default:
michael@0:             break;
michael@0:         }
michael@0:     }
michael@0: 	PL_DestroyOptState(opt);
michael@0: 
michael@0:     if (help) return -1;
michael@0: 
michael@0: 	if (PR_TRUE == debug_mode)
michael@0: 	{
michael@0: 		debug_out = PR_STDOUT;
michael@0: 		PR_fprintf(debug_out, "Test parameters\n");
michael@0: 		PR_fprintf(debug_out, "\tThreads involved: %d\n", thread_limit);
michael@0: 		PR_fprintf(debug_out, "\tIteration limit: %d\n", loop_limit);
michael@0: 		PR_fprintf(debug_out, "\tConcurrency: %d\n", concurrency);
michael@0: 		PR_fprintf(
michael@0: 			debug_out, "\tThread type: %s\n",
michael@0: 			(PR_GLOBAL_THREAD == thread_scope) ? "GLOBAL" : "LOCAL");
michael@0: 	}
michael@0: 
michael@0:     /*
michael@0:     ** The interesting part starts here
michael@0:     */
michael@0:     RCLock lock;
michael@0:     Shared* shared;
michael@0:     Home home(NULL, &lock);
michael@0:     Home* link = &home;
michael@0:     RCInterval timein, timeout = 0;
michael@0: 
michael@0:     /* Build up the string of objects */
michael@0:     for (thread_count = 1; thread_count <= thread_limit; ++thread_count)
michael@0:     {
michael@0:         shared = new Shared(thread_scope, link, &lock);
michael@0:         shared->Start();  /* make it run */
michael@0:         link = (Home*)shared;
michael@0: 	}
michael@0: 
michael@0:     /* Pass the message around the horn a few times */
michael@0:     for (loop_count = 1; loop_count <= loop_limit; ++loop_count)
michael@0:     {
michael@0: 		timein.SetToNow();
michael@0: 		for (inner_count = 0; inner_count < INNER_LOOPS; ++inner_count)
michael@0: 		{
michael@0: 			RCEnter entry(&lock);
michael@0: 			home.twiddle = PR_TRUE;
michael@0: 			shared->twiddle = PR_FALSE;
michael@0: 			shared->Notify();
michael@0: 			while (home.twiddle)
michael@0:             {
michael@0: 				failed = (PR_FAILURE == home.Wait()) ? PR_TRUE : PR_FALSE;
michael@0:             }
michael@0: 		}
michael@0: 		timeout += (RCInterval(RCInterval::now) - timein);
michael@0: 	}
michael@0: 
michael@0:     /* Figure out how well we did */
michael@0: 	if (debug_mode)
michael@0: 	{
michael@0: 		average = timeout.ToMicroseconds()
michael@0: 			/ (INNER_LOOPS * loop_limit * thread_count);
michael@0: 		PR_fprintf(
michael@0: 			debug_out, "Average switch times %d usecs for %d threads\n",
michael@0:             average, thread_limit);
michael@0: 	}
michael@0: 
michael@0:     /* Start reclamation process */
michael@0:     link = shared;
michael@0:     for (thread_count = 1; thread_count <= thread_limit; ++thread_count)
michael@0:     {
michael@0:         if (&home == link) break;
michael@0:         status = ((Shared*)link)->Interrupt();
michael@0: 		if (PR_SUCCESS != status)
michael@0:         {
michael@0:             failed = PR_TRUE;
michael@0:             if (debug_mode)
michael@0: 			    PL_FPrintError(debug_out, "Failed to interrupt");
michael@0:         }
michael@0: 		link = link->next; 
michael@0:     }
michael@0: 
michael@0:     for (thread_count = 1; thread_count <= thread_limit; ++thread_count)
michael@0:     {
michael@0:         link = shared->next;
michael@0:         status = shared->Join();
michael@0: 		if (PR_SUCCESS != status)
michael@0: 		{
michael@0:             failed = PR_TRUE;
michael@0:             if (debug_mode)
michael@0: 			    PL_FPrintError(debug_out, "Failed to join");
michael@0:         }
michael@0:         if (&home == link) break;
michael@0:         shared = (Shared*)link;
michael@0:     }
michael@0: 
michael@0:     PR_fprintf(PR_STDOUT, ((failed) ? "FAILED\n" : "PASSED\n"));
michael@0: 
michael@0:     failed |= (PR_SUCCESS == RCPrimordialThread::Cleanup());
michael@0: 
michael@0:     return ((failed) ? 1 : 0);
michael@0: }  /* main */
michael@0: 
michael@0: /* switch.c */