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authorLinus Torvalds <torvalds@linux-foundation.org>2016-10-14 15:17:12 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-10-14 15:17:12 -0700
commit5d89d9f502f9c33ed0270d716f238429861e1942 (patch)
tree6a353640e6836ca465f2dcf00323a7f8a793ae59 /Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c
parent50cff89837a43a7c62ac080de9742a298d6418b3 (diff)
parentfecf861e765b2f9ce1a0487c3940afaed80ef7a8 (diff)
downloadlinux-next-5d89d9f502f9c33ed0270d716f238429861e1942.tar.gz
Merge tag 'linux-kselftest-4.9-rc1-update' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kselftest updates from Shuah Khan: "This update consists of: - Fixes and improvements to existing tests - Moving code from Documentation to selftests, samples, and tools: * Moves dnotify_test, prctl, ptp, vDSO, ia64, watchdog, and networking tests from Documentation to selftests. * Moves mic/mpssd, misc-devices/mei, timers, watchdog, auxdisplay, and blackfin examples from Documentation to samples. * Moves accounting, laptops/dslm, and pcmcia/crc32hash tools from Documentation to tools. * Deletes BUILD_DOCSRC and its dependencies" * tag 'linux-kselftest-4.9-rc1-update' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (21 commits) selftests/futex: Check ANSI terminal color support Doc: update 00-INDEX files to reflect the runnable code move samples: move blackfin gptimers-example from Documentation tools: move pcmcia crc32hash tool from Documentation tools: move laptops dslm tool from Documentation tools: move accounting tool from Documentation samples: move auxdisplay example code from Documentation samples: move watchdog example code from Documentation samples: move timers example code from Documentation samples: move misc-devices/mei example code from Documentation samples: move mic/mpssd example code from Documentation selftests: Move networking/timestamping from Documentation selftests: move watchdog tests from Documentation/watchdog selftests: move ia64 tests from Documentation/ia64 selftests: move vDSO tests from Documentation/vDSO selftests: move ptp tests from Documentation/ptp selftests: move prctl tests from Documentation/prctl selftests: move dnotify_test from Documentation/filesystems selftests/timers: Add missing error code assignment before test selftests/zram: replace ZRAM_LZ4_COMPRESS ...
Diffstat (limited to 'Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c')
-rw-r--r--Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c97
1 files changed, 0 insertions, 97 deletions
diff --git a/Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c b/Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c
deleted file mode 100644
index f7499d1c0415..000000000000
--- a/Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c
+++ /dev/null
@@ -1,97 +0,0 @@
-/*
- * Tests for prctl(PR_GET_TSC, ...) / prctl(PR_SET_TSC, ...)
- *
- * Tests if the control register is updated correctly
- * at context switches
- *
- * Warning: this test will cause a very high load for a few seconds
- *
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <signal.h>
-#include <inttypes.h>
-#include <wait.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
-
-static uint64_t rdtsc(void)
-{
-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;
-}
-
-static void sigsegv_expect(int sig)
-{
- /* */
-}
-
-static void segvtask(void)
-{
- if (prctl(PR_SET_TSC, PR_TSC_SIGSEGV) < 0)
- {
- perror("prctl");
- exit(0);
- }
- signal(SIGSEGV, sigsegv_expect);
- alarm(10);
- rdtsc();
- fprintf(stderr, "FATAL ERROR, rdtsc() succeeded while disabled\n");
- exit(0);
-}
-
-
-static void sigsegv_fail(int sig)
-{
- fprintf(stderr, "FATAL ERROR, rdtsc() failed while enabled\n");
- exit(0);
-}
-
-static void rdtsctask(void)
-{
- if (prctl(PR_SET_TSC, PR_TSC_ENABLE) < 0)
- {
- perror("prctl");
- exit(0);
- }
- signal(SIGSEGV, sigsegv_fail);
- alarm(10);
- for(;;) rdtsc();
-}
-
-
-int main(void)
-{
- int n_tasks = 100, i;
-
- fprintf(stderr, "[No further output means we're allright]\n");
-
- for (i=0; i<n_tasks; i++)
- if (fork() == 0)
- {
- if (i & 1)
- segvtask();
- else
- rdtsctask();
- }
-
- for (i=0; i<n_tasks; i++)
- wait(NULL);
-
- exit(0);
-}
-