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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/tools/perf/arch/x86/util/tsc.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/tools/perf/arch/x86/util/tsc.c')
-rw-r--r--kernel/tools/perf/arch/x86/util/tsc.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/kernel/tools/perf/arch/x86/util/tsc.c b/kernel/tools/perf/arch/x86/util/tsc.c
new file mode 100644
index 000000000..fd2868490
--- /dev/null
+++ b/kernel/tools/perf/arch/x86/util/tsc.c
@@ -0,0 +1,48 @@
+#include <stdbool.h>
+#include <errno.h>
+
+#include <linux/perf_event.h>
+
+#include "../../perf.h"
+#include <linux/types.h>
+#include "../../util/debug.h"
+#include "../../util/tsc.h"
+#include "tsc.h"
+
+int perf_read_tsc_conversion(const struct perf_event_mmap_page *pc,
+ struct perf_tsc_conversion *tc)
+{
+ bool cap_user_time_zero;
+ u32 seq;
+ int i = 0;
+
+ while (1) {
+ seq = pc->lock;
+ rmb();
+ tc->time_mult = pc->time_mult;
+ tc->time_shift = pc->time_shift;
+ tc->time_zero = pc->time_zero;
+ cap_user_time_zero = pc->cap_user_time_zero;
+ rmb();
+ if (pc->lock == seq && !(seq & 1))
+ break;
+ if (++i > 10000) {
+ pr_debug("failed to get perf_event_mmap_page lock\n");
+ return -EINVAL;
+ }
+ }
+
+ if (!cap_user_time_zero)
+ return -EOPNOTSUPP;
+
+ return 0;
+}
+
+u64 rdtsc(void)
+{
+ unsigned int low, high;
+
+ asm volatile("rdtsc" : "=a" (low), "=d" (high));
+
+ return low | ((u64)high) << 32;
+}