[LTP] [PATCH] ltp/numa: add new test11

[Li Wang]

On Wed, Jan 25, 2017 at 3:33 AM, Cyril Hrubis <chrubis@suse.cz> wrote:
> Hi!
>> +# Verification of hugepage memory allocated on a node
>> +test11()
>> +{
>> +     Mem_huge=0
>> +
>> +     if [ ! -d "/sys/kernel/mm/hugepages/" ]; then
>> +             tst_brk TCONF "hugepage is not supported"
>
> This should be tst_res followed by a return on a next line. The
> tst_brk will exit the whole test just because hugepages are not
> supported.

Good catch, that would probably happened when we have new testcase12 in next.

>
>> +     fi
>> +
>> +     for node in $nodes_list; do
>> +             Ori_hpgs=$(cat /sys/devices/system/node/node${node}/hugepages/hugepages-${HPAGE_SIZE}kB/nr_hugepages)
>> +             echo 1 >/sys/devices/system/node/node${node}/hugepages/hugepages-${HPAGE_SIZE}kB/nr_hugepages
>
> Uh, so this sysfs knob controlls how much hugepages can be allocated on
> a node right? What if it was set to nonzero and some hugepages are
> allocated already? Shouldn't we rather set it to current value + 1 ?

Yes, we should consider that situation.

   echo '$Ori_hpgs + 1' > /sys/...

And, if it failed to allocate new hugepage, exit is necessary.

>
>> +             numactl --cpunodebind=$node --membind=$node support_numa $HUGE_PAGE &
>> +             pid=$!
>> +             wait_for_support_numa $pid
>> +
>> +             Mem_huge=$(echo $(numastat -p $pid |grep '^Huge' |awk '{print $'$((node+2))'}'))
>> +             Mem_huge=$(echo "$Mem_huge * 1024" |bc)
>
> Eh, why not just $((Mem_huge * 1024)) ?
>
>> +             if [ $(echo "$Mem_huge < $HPAGE_SIZE" | bc) -eq 1 ]; then
>
> Here as well, why not just if [ "$Mem_huge" -lt "$HPAGE_SIZE" ]; then

agree!

>
>> +                     tst_res TFAIL \
>> +                             "NUMA memory allocated in node$node is less than expected"
>> +                     return
>> +             fi
>> +
>> +             kill -CONT $pid >/dev/null 2>&1
>> +             echo $Ori_hpgs >/sys/devices/system/node/node${node}/hugepages/hugepages-${HPAGE_SIZE}kB/nr_hugepages
>> +     done
>> +
>> +     tst_res TPASS "NUMA local node hugepage memory allocated"
>> +}
>> +
>>  tst_run
>> diff --git a/testcases/kernel/numa/support_numa.c b/testcases/kernel/numa/support_numa.c
>> index eaf63e3..0241a19 100644
>> --- a/testcases/kernel/numa/support_numa.c
>> +++ b/testcases/kernel/numa/support_numa.c
>> @@ -22,7 +22,7 @@
>>  /*                                                                            */
>>  /* File:        support_numa.c                                                */
>>  /*                                                                            */
>> -/* Description: Allocates 1MB of memory and touches it to verify numa         */
>> +/* Description: Allocates memory and touches it to verify numa                */
>>  /*                                                                            */
>>  /* Author:      Sivakumar Chinnaiah  Sivakumar.C@in.ibm.com                   */
>>  /*                                                                            */
>> @@ -52,16 +52,43 @@ static void help(void)
>>       printf("Input:  Describe input arguments to this program\n");
>>       printf("        argv[1] == 1 then allocate 1MB of memory\n");
>>       printf("        argv[1] == 2 then allocate 1MB of share memory\n");
>> -     printf("        argv[1] == 3 then pause the program to catch sigint\n");
>> +     printf("        argv[1] == 3 then allocate 1HUGE PAGE SIZE of memory\n");
>> +     printf("        argv[1] == 4 then pause the program to catch sigint\n");
>>       printf("Exit:   On failure - Exits with non-zero value\n");
>>       printf("        On success - exits with 0 exit value\n");
>>
>>       exit(1);
>>  }
>>
>> +static int read_hugepagesize(void)
>> +{
>> +       FILE *fp;
>> +       char line[BUFSIZ], buf[BUFSIZ];
>> +       int val;
>> +
>> +       fp = fopen("/proc/meminfo", "r");
>> +       if (fp == NULL) {
>> +               fprintf(stderr, "Failed to open /proc/meminfo");
>> +               return 1;
>> +       }
>> +
>> +       while (fgets(line, BUFSIZ, fp) != NULL) {
>> +               if (sscanf(line, "%64s %d", buf, &val) == 2)
>> +                       if (strcmp(buf, "Hugepagesize:") == 0) {
>> +                               fclose(fp);
>> +                               return 1024 * val;
>> +                       }
>> +       }
>> +
>> +       fclose(fp);
>> +       fprintf(stderr, "can't find \"%s\" in %s", "Hugepagesize:", "/proc/meminfo");
>> +
>> +       return 1;
>> +}
>
> We should rather return 0 on a failure so that we can easily check
> hpsz != 0 in the main()

Sure.

>
>>  int main(int argc, char *argv[])
>>  {
>> -     int i, fd, rc;
>> +     int i, fd, rc, hpsz;
>>       char *buf = NULL;
>>       struct stat sb;
>>
>> @@ -114,6 +141,24 @@ int main(int argc, char *argv[])
>>               remove(TEST_SFILE);
>>               break;
>>       case 3:
>> +             hpsz = read_hugepagesize();
>
> Eh, we do not check for a failure and gracefully try to allocate 1 byte
> here? That does not sound right.

Yes, let me do that in next PATCH version.

>
>> +             buf = mmap(NULL, hpsz, PROT_READ | PROT_WRITE,
>> +                             MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB,
>> +                             -1, 0);
>> +
>> +             if (buf == MAP_FAILED){
>> +                     fprintf(stderr, "mmap failed\n");
>
> What about errno? We should rather use perror() here. Also coding style
> is wrong, you should use checkpatch.pl to check for common mistakes.

sure, thanks!

>
>> +                     exit(1);
>> +             }
>> +
>> +             memset(buf, 'a', hpsz);
>> +
>> +             raise(SIGSTOP);
>> +
>> +             munmap(buf, hpsz);
>> +             break;
>> +     case 4:
>>               raise(SIGSTOP);
>>               break;
>>       default:
>> --
>> 1.8.3.1
>>
>
> --
> Cyril Hrubis
> chrubis@suse.cz



-- 
Regards,
Li Wang
Email: liwang@redhat.com