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-rw-r--r--include/asm-i386/timex.h52
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diff --git a/include/asm-i386/timex.h b/include/asm-i386/timex.h
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+/*
+ * linux/include/asm-i386/timex.h
+ *
+ * i386 architecture timex specifications
+ */
+#ifndef _ASMi386_TIMEX_H
+#define _ASMi386_TIMEX_H
+
+#include <linux/config.h>
+#include <asm/processor.h>
+
+#ifdef CONFIG_X86_ELAN
+# define CLOCK_TICK_RATE 1189200 /* AMD Elan has different frequency! */
+#else
+# define CLOCK_TICK_RATE 1193182 /* Underlying HZ */
+#endif
+
+
+/*
+ * Standard way to access the cycle counter on i586+ CPUs.
+ * Currently only used on SMP.
+ *
+ * If you really have a SMP machine with i486 chips or older,
+ * compile for that, and this will just always return zero.
+ * That's ok, it just means that the nicer scheduling heuristics
+ * won't work for you.
+ *
+ * We only use the low 32 bits, and we'd simply better make sure
+ * that we reschedule before that wraps. Scheduling at least every
+ * four billion cycles just basically sounds like a good idea,
+ * regardless of how fast the machine is.
+ */
+typedef unsigned long long cycles_t;
+
+static inline cycles_t get_cycles (void)
+{
+ unsigned long long ret=0;
+
+#ifndef CONFIG_X86_TSC
+ if (!cpu_has_tsc)
+ return 0;
+#endif
+
+#if defined(CONFIG_X86_GENERIC) || defined(CONFIG_X86_TSC)
+ rdtscll(ret);
+#endif
+ return ret;
+}
+
+extern unsigned long cpu_khz;
+
+#endif
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