System call for current machine load ?

System call for current machine load ?

Post by Marco A. Hernand » Thu, 10 Oct 1996 04:00:00

Hi all:

        Under solaris 2.5 which system call would give you the current and
average load on the machine ....

        Any pointers appreciated.


Marco Hernandez


System call for current machine load ?

Post by Vic Abe » Thu, 10 Oct 1996 04:00:00


>    Under solaris 2.5 which system call would give you the current and
>average load on the machine ....

Check out the kstat(3K) interface.  I believe load averages are
available in the "unix" module named "system_misc".  Call kstat_open(),
then locate "system_misc" with kstat_lookup().  Use its returned
pointer to kstat_read() the values.  Then use kstat_data_lookup()
to find its "avenrun_1min", "avenrun_5min", and "avenrun_15min"
data.  Treat their value.l contents as doubles and divide them by
1<<8 to get the same numbers that uptime(1) reports.


1. Kernel Extension(system call) loaded but could not call it !!!!

Hi ,
can anybody tell me why I am unable to call my own system call.

/* This is the kernel extension I wrote */

testcall_entry(int cmd, struct uio *uio)

   if (cmd == CFG_INIT) {
      if (pincode(testcall_entry) != 0) { /* pin the kernel ext into
memory */
         return(ENOMEM);                  /* report error  */
   else {

/* These are the steps I followed to compile the extension */
cc -c -O -qlist -qsource testcall.c
ld -e testcall_entry -T512 -H512 -bI:./testcall.exp -bI:./kernex.exp
testcall.o -o testcall

/* this is a test system call */
int testcall()
        return 10;

Yes I did load the kernel extension and it was loaded successfully and
gave me kmid also.

/* This is a sample file to test system call */
main ()

        int val = 0;

        printf ("value before testcall %d\n",val);
        val = testcall ();
        printf ("value after testcall %d\n",val);

/* This is what I use to compile this program */
cc -bI:./kernex.exp -bI:./testcall.exp sample.c

/* This is the error it gives  when I run the a.out file */
exec(): 0509-036 Cannot load program a.out because of the following
        0509-023 Symbol testcall in a.out is not defined.
        0509-026 System error: Cannot run a file that does not have a
valid format.


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