diff options
| -rw-r--r-- | Makefile | 1 | ||||
| -rw-r--r-- | user/cow.c | 196 |
2 files changed, 0 insertions, 197 deletions
@@ -129,7 +129,6 @@ UPROGS=\ $U/_usertests\ $U/_wc\ $U/_zombie\ - $U/_cow\ fs.img: mkfs/mkfs README $(UPROGS) mkfs/mkfs fs.img README $(UPROGS) diff --git a/user/cow.c b/user/cow.c deleted file mode 100644 index 0426600..0000000 --- a/user/cow.c +++ /dev/null @@ -1,196 +0,0 @@ -// -// tests for copy-on-write fork() assignment. -// - -#include "kernel/types.h" -#include "kernel/memlayout.h" -#include "user/user.h" - -// allocate more than half of physical memory, -// then fork. this will fail in the default -// kernel, which does not support copy-on-write. -void -simpletest() -{ - uint64 phys_size = PHYSTOP - KERNBASE; - int sz = (phys_size / 3) * 2; - - printf(1, "simple: "); - - char *p = sbrk(sz); - if(p == (char*)0xffffffffffffffffL){ - printf(1, "sbrk(%d) failed\n", sz); - exit(); - } - - for(char *q = p; q < p + sz; q += 4096){ - *(int*)q = getpid(); - } - - int pid = fork(); - if(pid < 0){ - printf(1, "fork() failed\n"); - exit(); - } - - if(pid == 0) - exit(); - - wait(); - - if(sbrk(-sz) == (char*)0xffffffffffffffffL){ - printf(1, "sbrk(-%d) failed\n", sz); - exit(); - } - - printf(1, "ok\n"); -} - -// three processes all write COW memory. -// this causes more than half of physical memory -// to be allocated, so it also checks whether -// copied pages are freed. -void -threetest() -{ - uint64 phys_size = PHYSTOP - KERNBASE; - int sz = phys_size / 4; - int pid1, pid2; - - printf(1, "three: "); - - char *p = sbrk(sz); - if(p == (char*)0xffffffffffffffffL){ - printf(1, "sbrk(%d) failed\n", sz); - exit(); - } - - pid1 = fork(); - if(pid1 < 0){ - printf(1, "fork failed\n"); - exit(); - } - if(pid1 == 0){ - pid2 = fork(); - if(pid2 < 0){ - printf(1, "fork failed"); - exit(); - } - if(pid2 == 0){ - for(char *q = p; q < p + (sz/5)*4; q += 4096){ - *(int*)q = getpid(); - } - for(char *q = p; q < p + (sz/5)*4; q += 4096){ - if(*(int*)q != getpid()){ - printf(1, "wrong content\n"); - exit(); - } - } - exit(); - } - for(char *q = p; q < p + (sz/2); q += 4096){ - *(int*)q = 9999; - } - exit(); - } - - for(char *q = p; q < p + sz; q += 4096){ - *(int*)q = getpid(); - } - - wait(); - - sleep(1); - - for(char *q = p; q < p + sz; q += 4096){ - if(*(int*)q != getpid()){ - printf(1, "wrong content\n"); - exit(); - } - } - - if(sbrk(-sz) == (char*)0xffffffffffffffffL){ - printf(1, "sbrk(-%d) failed\n", sz); - exit(); - } - - printf(1, "ok\n"); -} - -char junk1[4096]; -int fds[2]; -char junk2[4096]; -char buf[4096]; -char junk3[4096]; - -// test whether copyout() simulates COW faults. -void -filetest() -{ - int parent = getpid(); - - printf(1, "file: "); - - buf[0] = 99; - - for(int i = 0; i < 4; i++){ - if(pipe(fds) != 0){ - printf(1, "pipe() failed\n"); - exit(); - } - int pid = fork(); - if(pid < 0){ - printf(1, "fork failed\n"); - exit(); - } - if(pid == 0){ - sleep(1); - if(read(fds[0], buf, sizeof(i)) != sizeof(i)){ - printf(1, "read failed\n"); - kill(parent); - exit(); - } - sleep(1); - int j = *(int*)buf; - if(j != i){ - printf(1, "read the wrong value\n"); - kill(parent); - exit(); - } - exit(); - } - if(write(fds[1], &i, sizeof(i)) != sizeof(i)){ - printf(1, "write failed\n"); - exit(); - } - } - - for(int i = 0; i < 4; i++) - wait(); - - if(buf[0] != 99){ - printf(1, "child overwrote parent\n"); - exit(); - } - - printf(1, "ok\n"); -} - -int -main(int argc, char *argv[]) -{ - simpletest(); - - // check that the first simpletest() freed the physical memory. - simpletest(); - - threetest(); - threetest(); - threetest(); - - filetest(); - - printf(1, "ALL COW TESTS PASSED\n"); - - exit(); -} |