mirror of
https://github.com/freebsd/freebsd-src
synced 2024-09-06 01:01:06 +00:00
mlock tests: Add a regression test
The test tries to trigger creation of a superpage mapping in an mlock()ed region. MFC after: 2 weeks
This commit is contained in:
parent
aa3bcaad51
commit
8f26ed01bd
|
@ -28,11 +28,15 @@
|
|||
#include <sys/cdefs.h>
|
||||
#include <sys/mman.h>
|
||||
#include <sys/ptrace.h>
|
||||
#include <sys/resource.h>
|
||||
#include <sys/wait.h>
|
||||
|
||||
#include <errno.h>
|
||||
#include <fcntl.h>
|
||||
#include <signal.h>
|
||||
#include <stdatomic.h>
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include <string.h>
|
||||
#include <unistd.h>
|
||||
|
||||
|
@ -161,12 +165,122 @@ ATF_TC_BODY(mlock__truncate_and_unlock, tc)
|
|||
ATF_REQUIRE(munlock(addr, len) == 0);
|
||||
}
|
||||
|
||||
/*
|
||||
* Exercise a corner case involving an interaction between mlock() and superpage
|
||||
* creation: a truncation of the object backing a mapping results in the
|
||||
* truncated region being unmapped by the pmap, but does not affect the logical
|
||||
* mapping. In particular, the truncated region remains mlock()ed. If the
|
||||
* mapping is later extended, a page fault in the formerly truncated region can
|
||||
* result in superpage creation via a call to pmap_enter(psind = 1).
|
||||
*/
|
||||
ATF_TC(mlock__superpage_fault);
|
||||
ATF_TC_HEAD(mlock__superpage_fault, tc)
|
||||
{
|
||||
atf_tc_set_md_var(tc, "require.user", "root");
|
||||
}
|
||||
ATF_TC_BODY(mlock__superpage_fault, tc)
|
||||
{
|
||||
struct rlimit rlim;
|
||||
void *addr1, *addr2;
|
||||
size_t len, pagesizes[MAXPAGESIZES];
|
||||
int count, error, shmfd;
|
||||
char vec;
|
||||
|
||||
count = getpagesizes(pagesizes, MAXPAGESIZES);
|
||||
ATF_REQUIRE_MSG(count >= 1,
|
||||
"failed to get page sizes: %s", strerror(errno));
|
||||
if (count == 1)
|
||||
atf_tc_skip("system does not support multiple page sizes");
|
||||
len = pagesizes[1];
|
||||
|
||||
error = getrlimit(RLIMIT_MEMLOCK, &rlim);
|
||||
ATF_REQUIRE_MSG(error == 0, "getrlimit: %s", strerror(errno));
|
||||
rlim.rlim_cur += len;
|
||||
rlim.rlim_max += len;
|
||||
error = setrlimit(RLIMIT_MEMLOCK, &rlim);
|
||||
ATF_REQUIRE_MSG(error == 0, "setrlimit: %s", strerror(errno));
|
||||
|
||||
shmfd = shm_open(SHM_ANON, O_RDWR | O_CREAT, 0600);
|
||||
ATF_REQUIRE_MSG(shmfd >= 0, "shm_open: %s", strerror(errno));
|
||||
error = ftruncate(shmfd, len);
|
||||
ATF_REQUIRE_MSG(error == 0, "ftruncate: %s", strerror(errno));
|
||||
|
||||
addr1 = mmap(NULL, len, PROT_READ | PROT_WRITE,
|
||||
MAP_SHARED | MAP_ALIGNED_SUPER, shmfd, 0);
|
||||
ATF_REQUIRE_MSG(addr1 != MAP_FAILED, "mmap: %s", strerror(errno));
|
||||
ATF_REQUIRE_MSG(((uintptr_t)addr1 & (len - 1)) == 0,
|
||||
"addr %p is misaligned", addr1);
|
||||
addr2 = mmap(NULL, len, PROT_READ,
|
||||
MAP_SHARED | MAP_ALIGNED_SUPER, shmfd, 0);
|
||||
ATF_REQUIRE_MSG(addr2 != MAP_FAILED, "mmap: %s", strerror(errno));
|
||||
ATF_REQUIRE_MSG(((uintptr_t)addr2 & (len - 1)) == 0,
|
||||
"addr %p is misaligned", addr2);
|
||||
|
||||
memset(addr1, 0x42, len);
|
||||
error = mincore(addr1, pagesizes[0], &vec);
|
||||
ATF_REQUIRE_MSG(error == 0, "mincore: %s", strerror(errno));
|
||||
if ((vec & MINCORE_SUPER) == 0)
|
||||
atf_tc_skip("initial superpage promotion failed");
|
||||
|
||||
error = mlock(addr2, len);
|
||||
ATF_REQUIRE_MSG(error == 0, "mlock: %s", strerror(errno));
|
||||
error = mincore(addr2, pagesizes[0], &vec);
|
||||
ATF_REQUIRE_MSG(error == 0, "mincore: %s", strerror(errno));
|
||||
ATF_REQUIRE((vec & MINCORE_SUPER) != 0);
|
||||
|
||||
/*
|
||||
* Free a page back to the superpage reservation, demoting both
|
||||
* mappings.
|
||||
*/
|
||||
error = ftruncate(shmfd, len - pagesizes[0]);
|
||||
ATF_REQUIRE_MSG(error == 0, "ftruncate: %s", strerror(errno));
|
||||
|
||||
/*
|
||||
* Extend the mapping back to its original size.
|
||||
*/
|
||||
error = ftruncate(shmfd, len);
|
||||
ATF_REQUIRE_MSG(error == 0, "ftruncate: %s", strerror(errno));
|
||||
|
||||
/*
|
||||
* Trigger re-promotion.
|
||||
*/
|
||||
error = mincore(addr1, pagesizes[0], &vec);
|
||||
ATF_REQUIRE_MSG(error == 0, "mincore: %s", strerror(errno));
|
||||
ATF_REQUIRE((vec & MINCORE_SUPER) == 0);
|
||||
memset((char *)addr1 + len - pagesizes[0], 0x43, pagesizes[0]);
|
||||
error = mincore(addr1, pagesizes[0], &vec);
|
||||
ATF_REQUIRE_MSG(error == 0, "mincore: %s", strerror(errno));
|
||||
ATF_REQUIRE((vec & MINCORE_SUPER) != 0);
|
||||
|
||||
/*
|
||||
* Trigger a read fault, which should install a superpage mapping
|
||||
* without promotion.
|
||||
*/
|
||||
error = mincore(addr2, pagesizes[0], &vec);
|
||||
ATF_REQUIRE_MSG(error == 0, "mincore: %s", strerror(errno));
|
||||
ATF_REQUIRE((vec & MINCORE_SUPER) == 0);
|
||||
(void)atomic_load(
|
||||
(_Atomic int *)(void *)((char *)addr2 + len - pagesizes[0]));
|
||||
error = mincore(addr2, pagesizes[0], &vec);
|
||||
ATF_REQUIRE_MSG(error == 0, "mincore: %s", strerror(errno));
|
||||
ATF_REQUIRE((vec & MINCORE_SUPER) != 0);
|
||||
|
||||
/*
|
||||
* Trigger demotion of the wired mapping.
|
||||
*/
|
||||
error = munlock(addr2, pagesizes[0]);
|
||||
ATF_REQUIRE_MSG(error == 0, "munlock: %s", strerror(errno));
|
||||
|
||||
ATF_REQUIRE(close(shmfd) == 0);
|
||||
}
|
||||
|
||||
ATF_TP_ADD_TCS(tp)
|
||||
{
|
||||
ATF_TP_ADD_TC(tp, mlock__copy_on_write_anon);
|
||||
ATF_TP_ADD_TC(tp, mlock__copy_on_write_vnode);
|
||||
ATF_TP_ADD_TC(tp, mlock__truncate_and_resize);
|
||||
ATF_TP_ADD_TC(tp, mlock__truncate_and_unlock);
|
||||
ATF_TP_ADD_TC(tp, mlock__superpage_fault);
|
||||
|
||||
return (atf_no_error());
|
||||
}
|
||||
|
|
Loading…
Reference in a new issue