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+/***********************************************************************
+ *
+ * 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*/