diff options
author | David S. Miller <davem@davemloft.net> | 2016-10-30 12:42:58 -0400 |
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committer | David S. Miller <davem@davemloft.net> | 2016-10-30 12:42:58 -0400 |
commit | 27058af401e49d88a905df000dd26f443fcfa8ce (patch) | |
tree | 819f32113d3b8374b9fbf72e2202d4c4d4511a60 /tools/testing/selftests/vDSO/vdso_test.c | |
parent | 357f4aae859b5d74554b0ccbb18556f1df4166c3 (diff) | |
parent | 2a26d99b251b8625d27aed14e97fc10707a3a81f (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Mostly simple overlapping changes.
For example, David Ahern's adjacency list revamp in 'net-next'
conflicted with an adjacency list traversal bug fix in 'net'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'tools/testing/selftests/vDSO/vdso_test.c')
-rw-r--r-- | tools/testing/selftests/vDSO/vdso_test.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/tools/testing/selftests/vDSO/vdso_test.c b/tools/testing/selftests/vDSO/vdso_test.c new file mode 100644 index 000000000000..8daeb7d7032c --- /dev/null +++ b/tools/testing/selftests/vDSO/vdso_test.c @@ -0,0 +1,52 @@ +/* + * vdso_test.c: Sample code to test parse_vdso.c + * Copyright (c) 2014 Andy Lutomirski + * Subject to the GNU General Public License, version 2 + * + * Compile with: + * gcc -std=gnu99 vdso_test.c parse_vdso.c + * + * Tested on x86, 32-bit and 64-bit. It may work on other architectures, too. + */ + +#include <stdint.h> +#include <elf.h> +#include <stdio.h> +#include <sys/auxv.h> +#include <sys/time.h> + +extern void *vdso_sym(const char *version, const char *name); +extern void vdso_init_from_sysinfo_ehdr(uintptr_t base); +extern void vdso_init_from_auxv(void *auxv); + +int main(int argc, char **argv) +{ + unsigned long sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR); + if (!sysinfo_ehdr) { + printf("AT_SYSINFO_EHDR is not present!\n"); + return 0; + } + + vdso_init_from_sysinfo_ehdr(getauxval(AT_SYSINFO_EHDR)); + + /* Find gettimeofday. */ + typedef long (*gtod_t)(struct timeval *tv, struct timezone *tz); + gtod_t gtod = (gtod_t)vdso_sym("LINUX_2.6", "__vdso_gettimeofday"); + + if (!gtod) { + printf("Could not find __vdso_gettimeofday\n"); + return 1; + } + + struct timeval tv; + long ret = gtod(&tv, 0); + + if (ret == 0) { + printf("The time is %lld.%06lld\n", + (long long)tv.tv_sec, (long long)tv.tv_usec); + } else { + printf("__vdso_gettimeofday failed\n"); + } + + return 0; +} |