[LTP] Question about kernel/syscall/signal/signal06.c

[Hongzhi, Song]

Hi Wang,

Sorry for bother you.

I find signal06 fails on qemux86-64 when qemu has a small number cores, 
e.g. "qemu -smp 1/2/4/6".

ERROR INFO:

signal06    0  TINFO  :  loop = 23
signal06    1  TFAIL  :  signal06.c:87: Bug Reproduced!

But if boot qemu with "-smp 16", the case has great chance to pass.


I have two questions about this case:

1. I don't know why multi-core will affect the case.

2. On failure situation, what does break the "while loop" shown in below 
code.

     while (D == VALUE && loop < LOOPS) {
         /* sys_tkill(pid, SIGHUP); asm to avoid save/reload
          * fp regs around c call */
         asm ("" : : "a"(__NR_tkill), "D"(pid), "S"(SIGHUP));
         asm ("syscall" : : : "ax");

         loop++;
     }

     ...

     if (loop == LOOPS) {
         tst_resm(TPASS, "%s call succeeded", TCID);
     } else {
 >>> tst_resm(TFAIL, "Bug Reproduced!");
         tst_exit();
     }


Thanks.

--Hongzhi