kern
changeset 71:c7bd6ec7b946
changed test_proc to modify memory after the fork in order to try out copy-on-write,
by pushing the result of getpid on the stack.
| author | John Tsiombikas <nuclear@member.fsf.org> |
|---|---|
| date | Thu, 13 Oct 2011 05:22:35 +0300 |
| parents | 219974492c7d |
| children | 3941e82b07f2 |
| files | src/test_proc.S |
| diffstat | 1 files changed, 11 insertions(+), 11 deletions(-) [+] |
line diff
1.1 --- a/src/test_proc.S Wed Oct 12 14:46:00 2011 +0300 1.2 +++ b/src/test_proc.S Thu Oct 13 05:22:35 2011 +0300 1.3 @@ -8,6 +8,12 @@ 1.4 movl $SYS_FORK, %eax 1.5 int $SYSCALL_INT 1.6 1.7 + /* test copy-on-write by pushing the pid to the stack 1.8 + * then use this value from the stack times 2 as a sleep 1.9 + * interval in the loop. 1.10 + */ 1.11 + movl $SYS_GETPID, %eax 1.12 + int $SYSCALL_INT 1.13 push %eax 1.14 1.15 infloop: 1.16 @@ -15,20 +21,14 @@ 1.17 movl $SYS_HELLO, %eax 1.18 int $SYSCALL_INT 1.19 1.20 - /* --- call getpid --- 1.21 - * we'll use the process id, multiplied by two as a 1.22 - * sleep interval, to avoid having the two test processes 1.23 - * sleep for identical amounts of time. 1.24 - */ 1.25 - movl $SYS_GETPID, %eax 1.26 - int $SYSCALL_INT 1.27 - movl %eax, %ebx 1.28 - shl $1, %ebx 1.29 1.30 /* --- sleep for (pid * 2) seconds --- 1.31 - * ebx (the argument to sleep) already contains the 1.32 - * correct value 1.33 + * grab the pid from the stack and shift it left to 1.34 + * multiply the pid by 2. Then use that as a sleep interval 1.35 + * in seconds. 1.36 */ 1.37 + movl (%esp), %ebx 1.38 + shl $1, %ebx 1.39 movl $SYS_SLEEP, %eax 1.40 int $SYSCALL_INT 1.41