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-rw-r--r--Documentation/prctl/disable-tsc-test.c94
1 files changed, 0 insertions, 94 deletions
diff --git a/Documentation/prctl/disable-tsc-test.c b/Documentation/prctl/disable-tsc-test.c
deleted file mode 100644
index 843c81e..0000000
--- a/Documentation/prctl/disable-tsc-test.c
+++ /dev/null
@@ -1,94 +0,0 @@
-/*
- * Tests for prctl(PR_GET_TSC, ...) / prctl(PR_SET_TSC, ...)
- *
- * Basic test to test behaviour of PR_GET_TSC and PR_SET_TSC
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <signal.h>
-#include <inttypes.h>
-
-
-#include <sys/prctl.h>
-#include <linux/prctl.h>
-
-/* Get/set the process' ability to use the timestamp counter instruction */
-#ifndef PR_GET_TSC
-#define PR_GET_TSC 25
-#define PR_SET_TSC 26
-# define PR_TSC_ENABLE 1 /* allow the use of the timestamp counter */
-# define PR_TSC_SIGSEGV 2 /* throw a SIGSEGV instead of reading the TSC */
-#endif
-
-const char *tsc_names[] =
-{
- [0] = "[not set]",
- [PR_TSC_ENABLE] = "PR_TSC_ENABLE",
- [PR_TSC_SIGSEGV] = "PR_TSC_SIGSEGV",
-};
-
-uint64_t rdtsc() {
-uint32_t lo, hi;
-/* We cannot use "=A", since this would use %rax on x86_64 */
-__asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
-return (uint64_t)hi << 32 | lo;
-}
-
-void sigsegv_cb(int sig)
-{
- int tsc_val = 0;
-
- printf("[ SIG_SEGV ]\n");
- printf("prctl(PR_GET_TSC, &tsc_val); ");
- fflush(stdout);
-
- if ( prctl(PR_GET_TSC, &tsc_val) == -1)
- perror("prctl");
-
- printf("tsc_val == %s\n", tsc_names[tsc_val]);
- printf("prctl(PR_SET_TSC, PR_TSC_ENABLE)\n");
- fflush(stdout);
- if ( prctl(PR_SET_TSC, PR_TSC_ENABLE) == -1)
- perror("prctl");
-
- printf("rdtsc() == ");
-}
-
-int main(int argc, char **argv)
-{
- int tsc_val = 0;
-
- signal(SIGSEGV, sigsegv_cb);
-
- printf("rdtsc() == %llu\n", (unsigned long long)rdtsc());
- printf("prctl(PR_GET_TSC, &tsc_val); ");
- fflush(stdout);
-
- if ( prctl(PR_GET_TSC, &tsc_val) == -1)
- perror("prctl");
-
- printf("tsc_val == %s\n", tsc_names[tsc_val]);
- printf("rdtsc() == %llu\n", (unsigned long long)rdtsc());
- printf("prctl(PR_SET_TSC, PR_TSC_ENABLE)\n");
- fflush(stdout);
-
- if ( prctl(PR_SET_TSC, PR_TSC_ENABLE) == -1)
- perror("prctl");
-
- printf("rdtsc() == %llu\n", (unsigned long long)rdtsc());
- printf("prctl(PR_SET_TSC, PR_TSC_SIGSEGV)\n");
- fflush(stdout);
-
- if ( prctl(PR_SET_TSC, PR_TSC_SIGSEGV) == -1)
- perror("prctl");
-
- printf("rdtsc() == ");
- fflush(stdout);
- printf("%llu\n", (unsigned long long)rdtsc());
- fflush(stdout);
-
- exit(EXIT_SUCCESS);
-}
-