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1 files changed, 1044 insertions, 0 deletions

diff --git a/jittertest/JitterTest.c b/jittertest/JitterTest.c
new file mode 100644
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--- /dev/null
+++ b/jittertest/JitterTest.c
@@ -0,0 +1,1044 @@
+/***********************************************************************
+ *
+ *  Copyright:          Daniel Measurement and Control, Inc.
+ *                           9753 Pine Lake Drive
+ *                             Houston, TX 77055
+ *
+ *  Created by: Vipin Malik and Gail Murray
+ *  Released under GPL by permission of Daniel Industries.
+ *
+ * This software is licensed under the GPL version 2. Plese see the file
+ * COPYING for details on the license.
+ *
+ * NO WARRANTY: Absolutely no claims of warranty or fitness of purpose
+ *              are made in this software. Please use at your own risk.
+ *
+ *  Filename:     JitterTest.c
+ *
+ *  Description:  Program to be used to measure wake jitter.
+ *                See README file for more info.
+ *
+ *
+ *  Revision History:
+ *  $Id: JitterTest.c,v 1.13 2005/11/07 11:15:20 gleixner Exp $
+ *  $Log: JitterTest.c,v $
+ *  Revision 1.13  2005/11/07 11:15:20  gleixner
+ *  [MTD / JFFS2] Clean up trailing white spaces
+ *
+ *  Revision 1.12  2001/08/10 19:23:11  vipin
+ *  Ready to be released under GPL! Added proper headers etc.
+ *
+ *  Revision 1.11  2001/07/09 15:35:50  vipin
+ *  Couple of new features:1. The program runs by default as a "regular"
+ *  (SCHED_OTHER) task by default, unless the -p n cmd line parameter is
+ *  specified. It then runs as SCHED_RR at that priority.
+ *  2. Added ability to send SIGSTOP/SIGCONT to a specified PID. This
+ *  would presumably be the PID of the JFFS2 GC task. SIGSTOP is sent
+ *  before writing to the fs, and a SIGCONT after the write is done.
+ *  3. The "pad" data now written to the file on the "fs under test" is
+ *  random, not sequential as previously.
+ *
+ *  Revision 1.10  2001/06/27 19:14:24  vipin
+ *  Now console file to log at can be specified from cmd line. This can enable
+ *  you to run two instances of the program- one logging to the /dev/console
+ *  and another to a regular file (if you want the data) or /dev/null if you don't.
+ *
+ *  Revision 1.9  2001/06/25 20:21:31  vipin
+ *  This is the latest version, NOT the one last checked in!
+ *
+ *  Revision 1.7  2001/06/18 22:36:19  vipin
+ *  Fix minor typo that excluded '\n' from msg on console.
+ *
+ *  Revision 1.6  2001/06/18 21:17:50  vipin
+ *  Added option to specify the amount of data written to outfile each period.
+ *  The regular info is written, but is then padded to the requested size.
+ *  This will enable testing of different sized writes to JFFS fs.
+ *
+ *  Revision 1.5  2001/06/08 19:36:23  vipin
+ *  All write() are now checked for return err code.
+ *
+ *  Revision 1.4  2001/06/06 23:10:31  vipin
+ *  Added README file.
+ *  In JitterTest.c: Changed operation of periodic timer to one shot. The timer is now
+ *  reset when the task wakes. This way every "jitter" is from the last time and
+ *  jitters from previous times are not accumulated and screw aroud with our display.
+ *
+ *  All jitter is now +ve. (as it should be). Also added a "read file" functionality
+ *  to test for jitter in task if we have to read from JFFS fs.
+ *  The program now also prints data to console- where it can be logged, interspersed with
+ *  other "interesting" printk's from the kernel and drivers (flash sector erases etc.)
+ *
+ *  Revision 1.3  2001/03/01 19:20:39  gmurray
+ *  Add priority scheduling. Shortened name of default output file.
+ *  Changed default interrupt period. Output delta time and jitter
+ *  instead of time of day.
+ *
+ *  Revision 1.2  2001/02/28 16:20:19  vipin
+ *  Added version control Id and log fields.
+ *
+ ***********************************************************************/
+/*************************** Included Files ***************************/
+#include <stdio.h>      /* fopen, printf, fprintf, fclose */
+#include <string.h>     /* strcpy, strcmp */
+#include <stdlib.h>     /* exit, atol, atoi */
+#include <sys/time.h>   /* setitimer, settimeofday, gettimeofday */
+#include <signal.h>     /* signal */
+#include <sched.h>      /* sched_setscheduler, sched_get_priority_min,*/
+/*   sched_get_priority_max */
+#include <unistd.h>     /* gettimeofday, sleep */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+
+
+
+/**************************** Enumerations ****************************/
+enum timerActions
+    {
+        ONESHOT,
+        AUTORESETTING
+    };
+
+
+
+/****************************** Constants *****************************/
+/* Exit error codes */
+#define EXIT_FILE_OPEN_ERR        (1)     /* error opening output file*/
+#define EXIT_REG_SIGALRM_ERR      (2)     /* error registering SIGALRM*/
+#define EXIT_REG_SIGINT_ERR       (3)     /* error registering SIGINT */
+#define EXIT_INV_INT_PERIOD       (4)     /* error invalid int. period*/
+#define EXIT_MIN_PRIORITY_ERR     (5)     /* error, minimum priority  */
+#define EXIT_MAX_PRIORITY_ERR     (6)     /* error, maximum priority  */
+#define EXIT_INV_SCHED_PRIORITY   (7)     /* error, invalid priority  */
+#define EXIT_SET_SCHEDULER_ERR    (8)     /* error, set scheduler     */
+#define EXIT_PREV_TIME_OF_DAY_ERR (9)     /* error, init. prev.       */
+/*   time of day            */
+
+#define MAX_FILE_NAME_LEN         (32)    /* maximum file name length */
+
+#define STRINGS_EQUAL             ((int) 0) /* strcmp value if equal  */
+
+#define MIN_INT_PERIOD_MILLISEC   (   5L) /* minimum interrupt period */
+#define MAX_INT_PERIOD_MILLISEC   (5000L) /* maximum interrupt period */
+#define DEF_INT_PERIOD_MILLISEC   (  10L) /* default interrupt period */
+
+#define READ_FILE_MESSAGE "This is a junk file. Must contain at least 1 byte though!\n"
+
+/* The user can specify that the program pad out the write file to
+   a given number of bytes. But a minimum number needs to be written. This
+   will contain the jitter info.
+*/
+#define MIN_WRITE_BYTES     30
+#define DEFAULT_WRITE_BYTES 30
+#define MAX_WRITE_BYTES 4096
+
+/* used for gen a printable ascii random # between spc and '~' */
+#define MIN_ASCII 32     /* <SPACE> can be char*/
+#define MAX_ASCII 126.0 /* needs to be float. See man rand()  */
+
+/*----------------------------------------------------------------------
+ * It appears that the preprocessor can't handle multi-line #if
+ * statements. Thus, the check on the default is divided into two
+ * #if statements.
+ *---------------------------------------------------------------------*/
+#if (DEF_INT_PERIOD_MILLISEC < MIN_INT_PERIOD_MILLISEC)
+#error *** Invalid default interrupt period. ***
+#endif
+
+#if (DEF_INT_PERIOD_MILLISEC > MAX_INT_PERIOD_MILLISEC)
+#error *** Invalid default interrupt period. ***
+#endif
+
+
+#define TRUE                      1  /* Boolean true value       */
+#define FALSE                     0
+
+/* Time conversion constants. */
+#define MILLISEC_PER_SEC          (1000L) /* milliseconds per second  */
+#define MICROSEC_PER_MILLISEC     (1000L) /* microsecs per millisec   */
+#define MICROSEC_PER_SEC          (1000000L) /* microsecs per second  */
+
+#define PRIORITY_POLICY           ((int) SCHED_RR) /* If specified iwth "-p" */
+
+
+
+/************************** Module Variables **************************/
+/* version identifier (value supplied by CVS)*/
+static const char Version[] = "$Id: JitterTest.c,v 1.13 2005/11/07 11:15:20 gleixner Exp $";
+
+static char OutFileName[MAX_FILE_NAME_LEN+1];  /* output file name            */
+static char LogFile[MAX_FILE_NAME_LEN+1] = "/dev/console"; /* default */
+static char ReadFile[MAX_FILE_NAME_LEN+1]; /* This file is read. Should
+                                              contain at least 1 byte */
+
+static int WriteBytes = DEFAULT_WRITE_BYTES; /* pad out file to these many bytes. */
+static int Fd1;                        /* fd where the above buffer if o/p */
+static int Cfd;                        /* fd to console (or file specified) */
+static int Fd2;                        /* fd for the ReadFile         */
+static int DoRead = FALSE;             /* should we attempt to ReadFile?*/
+static long InterruptPeriodMilliSec;   /* interrupt period, millisec  */
+static int MinPriority;                /* minimum scheduler priority  */
+static int MaxPriority;                /* maximum scheduler priority  */
+static int RequestedPriority;          /* requested priority          */
+static struct itimerval ITimer;        /* interrupt timer structure   */
+static struct timeval PrevTimeVal;     /* previous time structure     */
+static struct timeval CurrTimeVal;     /* current time structure      */
+static long LastMaxDiff = 0; /* keeps track of worst jitter encountered */
+
+static int GrabKProfile = FALSE; /* To help determine system bottle necks
+                                    this parameter can be set. This causes
+                                    the /proc/profile file to be read and
+                                    stored in unique filenames in current
+                                    dir, and indication to be o/p on the
+                                    /dev/console also.
+                                 */
+static long ProfileTriggerMSecs = 15000l; /* Jitter time in seconds that triggers
+                                       a snapshot of the profile to be taken
+
+                                    */
+static int SignalGCTask = FALSE; /* should be signal SIGSTOP/SIGCONT to gc task?*/
+static int GCTaskPID;
+
+static int RunAsRTTask = FALSE; /* default action unless priority is
+				   specified on cmd line */
+
+
+/********************* Local Function Prototypes **********************/
+void HandleCmdLineArgs(int argc, char *argv[]);
+void SetFileName(char * pFileName);
+void SetInterruptPeriod(char * pASCIIInterruptPeriodMilliSec);
+void SetSchedulerPriority(char * pASCIISchedulerPriority);
+
+void PrintVersionInfo(void);
+void PrintHelpInfo(void);
+
+int Write(int fd, void *buf, size_t bytes, int lineNo);
+
+void InitITimer(struct itimerval * pITimer, int action);
+
+/* For catching timer interrupts (SIGALRM). */
+void AlarmHandler(int sigNum);
+
+/* For catching Ctrl+C SIGINT. */
+void SignalHandler(int sigNum);
+
+
+
+/***********************************************************************
+ *  main function
+ *  return: exit code
+ ***********************************************************************/
+int main(
+    int argc,
+    char *argv[])
+{
+    struct sched_param schedParam;
+
+    int mypri;
+    char tmpBuf[200];
+
+
+    strcpy(OutFileName,"jitter.dat");
+    InterruptPeriodMilliSec = MIN_INT_PERIOD_MILLISEC;
+
+    /* Get the minimum and maximum priorities. */
+    MinPriority = sched_get_priority_min(PRIORITY_POLICY);
+    MaxPriority = sched_get_priority_max(PRIORITY_POLICY);
+    if (MinPriority == -1) {
+        printf("\n*** Unable to get minimum priority. ***\n");
+        exit(EXIT_MIN_PRIORITY_ERR);
+    }
+    if (MaxPriority == -1) {
+        printf("\n*** Unable to get maximum priority. ***\n");
+        exit(EXIT_MAX_PRIORITY_ERR);
+    }
+
+    /* Set requested priority to minimum value as default. */
+    RequestedPriority = MinPriority;
+
+    HandleCmdLineArgs(argc, argv);
+
+    if(mlockall(MCL_CURRENT|MCL_FUTURE) < 0){
+        printf("Could not lock task into memory. Bye\n");
+        perror("Error");
+    }
+
+    if(RunAsRTTask){
+
+        /* Set the priority. */
+        schedParam.sched_priority = RequestedPriority;
+	if (sched_setscheduler(
+			       0,
+			       PRIORITY_POLICY,
+			       &schedParam) != (int) 0) {
+	  printf("Exiting: Unsuccessful sched_setscheduler.\n");
+	  close(Fd1);
+	  exit(EXIT_SET_SCHEDULER_ERR);
+	}
+
+
+	/* Double check as I have some doubts that it's really
+	   running at realtime priority! */
+	if((mypri = sched_getscheduler(0)) != RequestedPriority)
+	  {
+	    printf("Not running with request priority %i. running with priority %i instead!\n",
+		   RequestedPriority, mypri);
+	  }else
+	    {
+	      printf("Running with %i priority. Good!\n", mypri);
+	    }
+
+    }
+
+    /*------------------------- Initializations --------------------------*/
+    if((Fd1 = open(OutFileName, O_RDWR|O_CREAT|O_SYNC)) <= 0)
+    {
+        perror("Cannot open outfile for write:");
+        exit(1);
+    }
+
+    /* If a request is made to read from a specified file, then create that
+       file and fill with junk data so that there is something there to read.
+    */
+    if(DoRead)
+    {
+
+        if((Fd2 = open(ReadFile, O_RDWR|O_CREAT|O_SYNC|O_TRUNC)) <= 0)
+        {
+            perror("cannot open read file:");
+            exit(1);
+        }else
+        {
+
+            /* Don't really care how much we write here */
+            if(write(Fd2, READ_FILE_MESSAGE, strlen(READ_FILE_MESSAGE)) < 0)
+            {
+                perror("Problems writing to readfile:");
+                exit(1);
+            }
+            lseek(Fd2, 0, SEEK_SET); /* position back to byte #0 */
+        }
+    }
+
+
+
+    /* Also log output to console. This way we can capture it
+       on a serial console to a log file.
+    */
+    if((Cfd   = open(LogFile, O_WRONLY|O_SYNC)) <= 0)
+    {
+        perror("cannot open o/p logfile:");
+        exit(1);
+    }
+
+
+    /* Set-up handler for periodic interrupt. */
+    if (signal(SIGALRM, &AlarmHandler) == SIG_ERR) {
+        printf("Couldn't register signal handler for SIGALRM.\n");
+        sprintf(tmpBuf,
+                "Couldn't register signal handler for SIGALRM.\n");
+        Write(Fd1, tmpBuf, strlen(tmpBuf), __LINE__);
+
+        close(Fd1);
+        exit(EXIT_REG_SIGALRM_ERR);
+    }
+
+    /* Set-up handler for Ctrl+C to exit the program. */
+    if (signal(SIGINT, &SignalHandler) == SIG_ERR) {
+        printf("Couldn't register signal handler for SIGINT.\n");
+        sprintf(tmpBuf,
+                "Couldn't register signal handler for SIGINT.\n");
+        Write(Fd1, tmpBuf, strlen(tmpBuf), __LINE__);
+
+        close(Fd1);
+        exit(EXIT_REG_SIGINT_ERR);
+    }
+
+    printf("Press Ctrl+C to exit the program.\n");
+    printf("Output File:        %s\n", OutFileName);
+    printf("Scheduler priority: %d\n", RequestedPriority);
+    sprintf(tmpBuf, "\nScheduler priority: %d\n",
+            RequestedPriority);
+    Write(Fd1, tmpBuf, strlen(tmpBuf), __LINE__);
+
+    Write(Cfd, tmpBuf, strlen(tmpBuf), __LINE__);
+
+    printf("Interrupt period:   %ld milliseconds\n",
+           InterruptPeriodMilliSec);
+    sprintf(tmpBuf, "Interrupt period:   %ld milliseconds\n",
+            InterruptPeriodMilliSec);
+
+    Write(Fd1, tmpBuf, strlen(tmpBuf), __LINE__);
+
+    Write(Cfd, tmpBuf, strlen(tmpBuf), __LINE__);
+
+
+    fflush(0);
+
+
+
+    /* Initialize the periodic timer. */
+    InitITimer(&ITimer, ONESHOT);
+
+    /* Initialize "previous" time. */
+    if (gettimeofday(&PrevTimeVal, NULL) != (int) 0) {
+        printf("Exiting - ");
+        printf("Unable to initialize previous time of day.\n");
+        sprintf(tmpBuf, "Exiting - ");
+        Write(Fd1, tmpBuf, strlen(tmpBuf), __LINE__);
+
+        sprintf(tmpBuf,
+                "Unable to initialize previous time of day.\n");
+
+        Write(Fd1, tmpBuf, strlen(tmpBuf), __LINE__);
+
+    }
+
+    /* Start the periodic timer. */
+    setitimer(ITIMER_REAL, &ITimer, NULL);
+
+
+    while(TRUE) {    /* Intentional infinite loop. */
+        /* Sleep for one second. */
+        sleep((unsigned int) 1);
+    }
+
+    /* Just in case. File should be closed in SignalHandler. */
+    close(Fd1);
+    close(Cfd);
+
+    return 0;
+}
+
+
+
+
+/***********************************************************************
+ *                                SignalHandler
+ *  This is a handler for the SIGINT signal. It is assumed that the
+ *  SIGINT is due to the user pressing Ctrl+C to halt the program.
+ *  output: N/A
+ ***********************************************************************/
+void SignalHandler(
+    int sigNum)
+{
+
+    char tmpBuf[200];
+
+    /* Note sigNum not used. */
+    printf("Ctrl+C detected. Worst Jitter time was:%fms.\nJitterTest exiting.\n",
+           (float)LastMaxDiff/1000.0);
+
+    sprintf(tmpBuf,
+            "\nCtrl+C detected. Worst Jitter time was:%fms\nJitterTest exiting.\n",
+            (float)LastMaxDiff/1000.0);
+    Write(Fd1, tmpBuf, strlen(tmpBuf), __LINE__);
+
+    Write(Cfd, tmpBuf, strlen(tmpBuf), __LINE__);
+
+    close(Fd1);
+    close(Cfd);
+    exit(0);
+}
+
+
+
+
+
+/*
+  A snapshot of the /proc/profile needs to be taken.
+  This is stored as a new file every time, and the
+  stats reset by doing a (any) write to the /proc/profile
+  file.
+ */
+void doGrabKProfile(int jitterusec, char *fileName)
+{
+    int fdSnapshot;
+    int fdProfile;
+    int readBytes;
+    char readBuf[4096];
+
+    if((fdSnapshot = open(fileName, O_WRONLY | O_CREAT)) <= 0)
+    {
+        fprintf(stderr, "Could not open file %s.\n", fileName);
+        perror("Error:");
+        return;
+    }
+
+    if((fdProfile = open("/proc/profile", O_RDWR)) <= 0)
+    {
+        fprintf(stderr, "Could not open file /proc/profile. Make sure you booted with profile=2\n");
+        close(fdSnapshot);
+        return;
+    }
+
+    while((readBytes = read(fdProfile, readBuf, sizeof(readBuf))) > 0)
+    {
+        write(fdSnapshot, readBuf, readBytes);
+    }
+
+    close(fdSnapshot);
+
+    if(write(fdProfile, readBuf, 1) != 1)
+    {
+        perror("Could Not clear profile by writing to /proc/profile:");
+    }
+
+    close(fdProfile);
+
+
+
+}/* end doGrabKProfile()*/
+
+
+/*
+  Call this routine to clear the kernel profiling buffer /proc/profile
+*/
+void clearProfileBuf(void){
+
+
+  int fdProfile;
+  char readBuf[10];
+
+
+  if((fdProfile = open("/proc/profile", O_RDWR)) <= 0)
+    {
+      fprintf(stderr, "Could not open file /proc/profile. Make sure you booted with profile=2\n");
+      return;
+    }
+
+
+  if(write(fdProfile, readBuf, 1) != 1)
+    {
+      perror("Could Not clear profile by writing to /proc/profile:");
+    }
+
+  close(fdProfile);
+
+
+}/* end clearProfileBuf() */
+
+
+
+
+
+/***********************************************************************
+ *                                AlarmHandler
+ *  This is a handler for the SIGALRM signal (due to the periodic
+ *  timer interrupt). It prints the time (seconds) to
+ *  the output file.
+ *  output: N/A
+ ***********************************************************************/
+void AlarmHandler(
+    int sigNum)                     /* signal number (not used)         */
+{
+
+    long timeDiffusec;  /* diff time in micro seconds */
+    long intervalusec;
+
+
+    char tmpBuf[MAX_WRITE_BYTES];
+    int cntr;
+    char padChar;
+
+    static int profileFileNo = 0;
+    char profileFileName[150];
+
+    static int seedStarter = 0; /* carries over rand info to next time
+				   where time() will be the same as this time
+				   if invoked < 1sec apart.
+				*/
+
+    if (gettimeofday(&CurrTimeVal, NULL) == (int) 0) {
+
+        /*----------------------------------------------------------------
+         * Compute the elapsed time between the current and previous
+         * time of day values and store the result.
+         *
+         * Print the elapsed time to the output file.
+         *---------------------------------------------------------------*/
+
+        timeDiffusec = (long)(((((long long)CurrTimeVal.tv_sec) * 1000000L) + CurrTimeVal.tv_usec) -
+                        (((long long)PrevTimeVal.tv_sec * 1000000L) + PrevTimeVal.tv_usec));
+
+        sprintf(tmpBuf," %f ms  ", (float)timeDiffusec/1000.0);
+
+        intervalusec = InterruptPeriodMilliSec * 1000L;
+
+        timeDiffusec = timeDiffusec - intervalusec;
+
+        sprintf(&tmpBuf[strlen(tmpBuf)]," %f ms", (float)timeDiffusec/1000.0);
+
+
+	/* should we send a SIGSTOP/SIGCONT to the specified PID? */
+	if(SignalGCTask){
+
+	  if(kill(GCTaskPID, SIGSTOP) < 0){
+
+	    perror("error:");
+	  }
+	}
+
+
+        /* Store some historical #'s */
+        if(abs(timeDiffusec) > LastMaxDiff)
+	{
+            LastMaxDiff = abs(timeDiffusec);
+            sprintf(&tmpBuf[strlen(tmpBuf)],"!");
+
+	    if((GrabKProfile == TRUE) && (ProfileTriggerMSecs < (abs(timeDiffusec)/1000)))
+	      {
+		  sprintf(profileFileName, "JitterTest.profilesnap-%i", profileFileNo);
+
+		  /* go and grab the kernel performance profile. */
+		  doGrabKProfile(timeDiffusec, profileFileName);
+		  profileFileNo++; /* unique name next time */
+
+		  /* Say so on the console so that a marker gets put in the console log */
+		  sprintf(&tmpBuf[strlen(tmpBuf)],"<Profile saved in file:%s>",
+			  profileFileName);
+
+	      }
+
+        }
+
+
+
+
+        sprintf(&tmpBuf[strlen(tmpBuf)],"\n"); /* CR for the data going out of the console */
+
+        Write(Cfd, tmpBuf, strlen(tmpBuf), __LINE__);
+
+
+        /* The "-1" below takes out the '\n' at the end that we appended for the msg printed on
+         the console.*/
+        sprintf(&tmpBuf[strlen(tmpBuf)-1]," PadBytes:");
+
+        /* Now pad the output file if requested by user. */
+        if(WriteBytes > MIN_WRITE_BYTES)
+        {
+
+	    /* start from a new place every time */
+	    srand(time(NULL) + seedStarter);
+
+            /* already written MIN_WRITE_BYTES by now */
+            for(cntr = strlen(tmpBuf); cntr < WriteBytes - 1 ; cntr++) /* "-1" adj for '\n' at end */
+            {
+	        /* don't accept any # < 'SPACE' */
+	        padChar = (char)(MIN_ASCII+(int)((MAX_ASCII-(float)MIN_ASCII)*rand()/(RAND_MAX+1.0)));
+
+
+                /*
+                padChar = (cntr % (126-33)) + 33;
+		*/
+
+                tmpBuf[cntr] = padChar;
+            }
+
+	    seedStarter = tmpBuf[cntr-1]; /* save for next time */
+
+            tmpBuf[cntr] = '\n'; /* CR for the data going into the outfile. */
+            tmpBuf[cntr+1] = '\0'; /* NULL terminate the string */
+        }
+
+        /* write out the entire line to the output file. */
+        Write(Fd1, tmpBuf, strlen(tmpBuf), __LINE__);
+
+
+        /* Read a byte from the specified file */
+        if(DoRead)
+        {
+
+            read(Fd2, tmpBuf, 1);
+            lseek(Fd2, 0, SEEK_SET); /* back to start */
+        }
+
+
+        /* Start the periodic timer again. */
+        setitimer(ITIMER_REAL, &ITimer, NULL);
+
+
+        /* Update previous time with current time. */
+        PrevTimeVal.tv_sec  = CurrTimeVal.tv_sec;
+        PrevTimeVal.tv_usec = CurrTimeVal.tv_usec;
+    }
+
+    else {
+        sprintf(tmpBuf, "gettimeofday error \n");
+        Write(Fd1, tmpBuf, strlen(tmpBuf), __LINE__);
+
+        printf("gettimeofday error \n");
+    }
+
+    /* now clear the profiling buffer */
+    if(GrabKProfile == TRUE){
+
+      clearProfileBuf();
+    }
+
+    /* should we send a SIGSTOP/SIGCONT to the specified PID? */
+    if(SignalGCTask){
+
+      if(kill(GCTaskPID, SIGCONT) < 0){
+
+	perror("error:");
+      }
+    }
+
+
+    return;
+}
+
+
+
+/***********************************************************************
+ *                                 InitITimer
+ *  This function initializes the 'struct itimerval' structure whose
+ *  address is passed to interrupt every InterruptPeriodMilliSec.
+ *  output: N/A
+ ***********************************************************************/
+void InitITimer(
+    struct itimerval * pITimer,      /* pointer to interrupt timer struct*/
+    int action)                      /* ONESHOT or autosetting? */
+{
+    long seconds;                   /* seconds portion of int. period   */
+    long microSeconds;              /* microsec. portion of int. period */
+
+    /*--------------------------------------------------------------------
+     * Divide the desired interrupt period into its seconds and
+     * microseconds components.
+     *-------------------------------------------------------------------*/
+    if (InterruptPeriodMilliSec < MILLISEC_PER_SEC)  {
+        seconds = 0L;
+        microSeconds = InterruptPeriodMilliSec * MICROSEC_PER_MILLISEC;
+    }
+    else {
+        seconds = InterruptPeriodMilliSec / MILLISEC_PER_SEC;
+        microSeconds =
+            (InterruptPeriodMilliSec - (seconds * MILLISEC_PER_SEC)) *
+            MICROSEC_PER_MILLISEC;
+    }
+
+    /* Initialize the interrupt period structure. */
+    pITimer->it_value.tv_sec     = seconds;
+    pITimer->it_value.tv_usec    = microSeconds;
+
+    if(action == ONESHOT)
+    {
+        /* This will (should) prevent the timer from restarting itself */
+        pITimer->it_interval.tv_sec  = 0;
+        pITimer->it_interval.tv_usec = 0;
+    }else
+    {
+        pITimer->it_interval.tv_sec  = seconds;
+        pITimer->it_interval.tv_usec = microSeconds;
+
+    }
+
+    return;
+}
+
+
+/***********************************************************************
+ *                             HandleCmdLineArgs
+ *  This function handles the command line arguments.
+ *  output: stack size
+ ***********************************************************************/
+void HandleCmdLineArgs(
+    int argc,                       /* number of command-line arguments */
+    char *argv[])                   /* ptrs to command-line arguments   */
+{
+    int argNum;                     /* argument number                  */
+
+    if (argc > (int) 1) {
+
+        for (argNum = (int) 1; argNum < argc; argNum++) {
+
+            /* The command line contains an argument. */
+
+            if ((strcmp(argv[argNum],"--version") == STRINGS_EQUAL) ||
+                (strcmp(argv[argNum],"-v")        == STRINGS_EQUAL)) {
+                /* Print version information and exit. */
+                PrintVersionInfo();
+                exit(0);
+            }
+
+            else if ((strcmp(argv[argNum],"--help") == STRINGS_EQUAL) ||
+                     (strcmp(argv[argNum],"-h")     == STRINGS_EQUAL) ||
+                     (strcmp(argv[argNum],"-?")     == STRINGS_EQUAL)) {
+                /* Print help information and exit. */
+                PrintHelpInfo();
+                exit(0);
+            }
+
+            else if ((strcmp(argv[argNum],"--file") == STRINGS_EQUAL) ||
+                     (strcmp(argv[argNum],"-f")     == STRINGS_EQUAL)) {
+                /* Set the name of the output file. */
+                ++argNum;
+                if (argNum < argc) {
+                    SetFileName(argv[argNum]);
+                }
+                else {
+                    printf("*** Output file name not specified. ***\n");
+                    printf("Default output file name will be used.\n");
+                }
+            }
+
+            else if ((strcmp(argv[argNum],"--time") == STRINGS_EQUAL) ||
+                     (strcmp(argv[argNum],"-t")     == STRINGS_EQUAL)) {
+                /* Set the interrupt period. */
+                ++argNum;
+                if (argNum < argc) {
+                    SetInterruptPeriod(argv[argNum]);
+                }
+                else {
+                    printf("*** Interrupt period not specified. ***\n");
+                    printf("Default interrupt period will be used.\n");
+                }
+
+            }
+
+            else if ((strcmp(argv[argNum],"--priority") ==
+                      STRINGS_EQUAL) ||
+                     (strcmp(argv[argNum],"-p")       == STRINGS_EQUAL)) {
+                /* Set the scheduler priority. */
+                ++argNum;
+                if (argNum < argc) {
+                    SetSchedulerPriority(argv[argNum]);
+                }
+                else {
+                    printf("*** Scheduler priority not specified. ***\n");
+                    printf("Default scheduler priority will be used.\n");
+                }
+
+            }
+
+            else if ((strcmp(argv[argNum],"--readfile") ==
+                      STRINGS_EQUAL) ||
+                     (strcmp(argv[argNum],"-r")       == STRINGS_EQUAL)) {
+                /* Set the file to read*/
+                ++argNum;
+
+                strncpy(ReadFile, argv[argNum], sizeof(ReadFile));
+                DoRead = TRUE;
+            }
+
+            else if ((strcmp(argv[argNum],"--write_bytes") ==
+                      STRINGS_EQUAL) ||
+                     (strcmp(argv[argNum],"-w")       == STRINGS_EQUAL)) {
+                /* Set the file to read*/
+                ++argNum;
+
+                WriteBytes = atoi(argv[argNum]);
+
+                if(WriteBytes < MIN_WRITE_BYTES)
+                {
+                    printf("Writing less than %i bytes is not allowed. Bye.\n",
+                           MIN_WRITE_BYTES);
+                    exit(0);
+                }
+
+
+            }
+
+            else if ((strcmp(argv[argNum],"--consolefile") ==
+                      STRINGS_EQUAL) ||
+                     (strcmp(argv[argNum],"-c")       == STRINGS_EQUAL)) {
+	      /* Set the file to log console log on. */
+	      ++argNum;
+
+	      strncpy(LogFile, argv[argNum], sizeof(LogFile));
+            }
+
+            else if ((strcmp(argv[argNum],"--grab_kprofile") ==
+                      STRINGS_EQUAL))
+	      {
+                /* We will read the /proc/profile file on configurable timeout */
+                GrabKProfile = TRUE;
+
+                ++argNum;
+
+                /* If the jittter is > this #, then the profile is grabbed. */
+                ProfileTriggerMSecs = (long) atoi(argv[argNum]);
+
+		if(ProfileTriggerMSecs <= 0){
+
+		  printf("Illegal value for profile trigger threshold.\n");
+		  exit(0);
+		}
+	      }
+
+            else if ((strcmp(argv[argNum],"--siggc") ==
+                      STRINGS_EQUAL))
+	      {
+                /* We will SIGSTOP/SIGCONT the specified pid */
+                SignalGCTask = TRUE;
+
+                ++argNum;
+
+                GCTaskPID = atoi(argv[argNum]);
+
+		if(ProfileTriggerMSecs <= 0){
+
+		  printf("Illegal value for JFFS(2) GC task pid.\n");
+		  exit(0);
+		}
+	      }
+
+
+            else {
+	      /* Unknown argument. Print help information and exit. */
+	      printf("Invalid option %s\n", argv[argNum]);
+	      printf("Try 'JitterTest --help' for more information.\n");
+	      exit(0);
+            }
+        }
+    }
+
+    return;
+}
+
+
+/***********************************************************************
+ *                                SetFileName
+ *  This function sets the output file name.
+ *  output: N/A
+ ***********************************************************************/
+void SetFileName(
+    char * pFileName)               /* ptr to desired output file name  */
+{
+    size_t fileNameLen;             /* file name length (bytes)         */
+
+    /* Check file name length. */
+    fileNameLen = strlen(pFileName);
+    if (fileNameLen > (size_t) MAX_FILE_NAME_LEN) {
+        printf("File name %s exceeds maximum length %d.\n",
+               pFileName, MAX_FILE_NAME_LEN);
+        exit(0);
+    }
+
+    /* File name length is OK so save the file name. */
+    strcpy(OutFileName, pFileName);
+
+    return;
+}
+
+
+/***********************************************************************
+ *                             SetInterruptPeriod
+ *  This function sets the interrupt period.
+ *  output: N/A
+ ***********************************************************************/
+void SetInterruptPeriod(
+    char *                          /* ptr to desired interrupt period  */
+    pASCIIInterruptPeriodMilliSec)
+{
+    long period;                    /* interrupt period                 */
+
+    period = atol(pASCIIInterruptPeriodMilliSec);
+    if ((period < MIN_INT_PERIOD_MILLISEC) ||
+        (period > MAX_INT_PERIOD_MILLISEC)) {
+        printf("Invalid interrupt period: %ld ms.\n", period);
+        exit(EXIT_INV_INT_PERIOD);
+    }
+    else {
+        InterruptPeriodMilliSec = period;
+    }
+    return;
+}
+
+
+/***********************************************************************
+ *                            SetSchedulerPriority
+ *  This function sets the desired scheduler priority.
+ *  output: N/A
+ ***********************************************************************/
+void SetSchedulerPriority(
+    char * pASCIISchedulerPriority) /* ptr to desired scheduler priority*/
+{
+    int priority;                   /* desired scheduler priority value */
+
+    priority = atoi(pASCIISchedulerPriority);
+    if ((priority < MinPriority) ||
+        (priority > MaxPriority)) {
+        printf("Scheduler priority %d outside of range [%d, %d]\n",
+               priority, MinPriority, MaxPriority);
+        exit(EXIT_INV_SCHED_PRIORITY);
+    }
+    else {
+        RequestedPriority = priority;
+	RunAsRTTask = TRUE; /* We shall run as a POSIX real time task */
+    }
+    return;
+}
+
+
+/***********************************************************************
+ *                              PrintVersionInfo
+ *  This function prints version information.
+ *  output: N/A
+ ***********************************************************************/
+void PrintVersionInfo(void)
+{
+    printf("JitterTest version %s\n", Version);
+    printf("Copyright (c) 2001, Daniel Industries, Inc.\n");
+    return;
+}
+
+
+/***********************************************************************
+ *                               PrintHelpInfo
+ *  This function prints help information.
+ *  output: N/A
+ ***********************************************************************/
+void PrintHelpInfo(void)
+{
+    printf("Usage: JitterTest [options]\n");
+    printf("       *** Requires root privileges. ***\n");
+    printf("Option:\n");
+    printf("  [-h, --help, -?]           Print this message and exit.\n");
+    printf("  [-v, --version]            ");
+    printf(         "Print the version number of JitterTest and exit.\n");
+    printf("  [-f FILE, --file FILE]     Set output file name to FILE. Typically you would put this on the fs under test\n");
+    printf("  [-c FILE, --consolefile]   Set device or file to write the console log to.\n\tTypically you would set this to /dev/console and save it on another computer.\n");
+    printf("  [-w BYTES, --write_bytes BYTES  Write BYTES to FILE each period.\n");
+    printf("  [-r FILE, --readfile FILE]     Also read 1 byte every cycle from FILE. FILE will be created and filled with data.\n");
+    printf("  [-t <n>, --time <n>]       ");
+    printf(         "Set interrupt period to <n> milliseconds.\n");
+    printf("                           ");
+    printf(         "Range: [%ld, %ld] milliseconds.\n",
+                    MIN_INT_PERIOD_MILLISEC, MAX_INT_PERIOD_MILLISEC);
+    printf("  [-p <n>, --priority <n>]  ");
+    printf(         "Set scheduler priority to <n>.\n");
+    printf("                           ");
+    printf(         "Range: [%d, %d] (higher number = higher priority)\n",
+                    MinPriority, MaxPriority);
+    printf("  [--grab_kprofile <THRESHOLD in ms>]    Read the /proc/profile if jitter is > THRESHOLD and store in file.\n");
+    printf("  [--siggc <PID>]   Before writing to fs send SIGSTOP to PID. After write send SIGCONT\n");
+    return;
+
+}
+
+
+/* A common write that checks for write errors and exits. Pass it __LINE__ for lineNo */
+int Write(int fd, void *buf, size_t bytes, int lineNo)
+{
+
+    int err;
+
+    err = write(fd, buf, bytes);
+
+    if(err < bytes)
+    {
+
+        printf("Write Error at line %i! Wanted to write %i bytes, but wrote only %i bytes.\n",
+               lineNo, bytes, err);
+        perror("Write did not complete. Error. Bye:"); /* show error from errno. */
+	exit(1);
+
+    }
+
+    return err;
+
+}/* end Write*/