clocksource: Replace vread with generic arch data

The vread field was bloating struct clocksource everywhere except
x86_64, and I want to change the way this works on x86_64, so let's
split it out into per-arch data.

Cc: x86@kernel.org
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: linux-ia64@vger.kernel.org
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/3ae5ec76a168eaaae63f08a2a1060b91aa0b7759.1310563276.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

2 files changed, 12 insertions, 2 deletions

diff --git a/include/asm-generic/clocksource.h b/include/asm-generic/clocksource.h
new file mode 100644
index 000000000000..0a462d3fb05e
--- /dev/null
+++ b/include/asm-generic/clocksource.h
@@ -0,0 +1,4 @@
+/*
+ * Architectures should override this file to add private userspace
+ * clock magic if needed.
+ */
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index d4646b48dc4a..0fb83c224471 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -22,6 +22,8 @@
 typedef u64 cycle_t;
 struct clocksource;
 
+#include <asm/clocksource.h>
+
 /**
  * struct cyclecounter - hardware abstraction for a free running counter
  *      Provides completely state-free accessors to the underlying hardware.
@@ -153,7 +155,7 @@ extern u64 timecounter_cyc2time(struct timecounter *tc,
  * @shift:              cycle to nanosecond divisor (power of two)
  * @max_idle_ns:        max idle time permitted by the clocksource (nsecs)
  * @flags:              flags describing special properties
- * @vread:              vsyscall based read
+ * @archdata:           arch-specific data
  * @suspend:            suspend function for the clocksource, if necessary
  * @resume:             resume function for the clocksource, if necessary
  */
@@ -175,10 +177,14 @@ struct clocksource {
 #else
 #define CLKSRC_FSYS_MMIO_SET(mmio, addr)      do { } while (0)
 #endif
+
+#ifdef __ARCH_HAS_CLOCKSOURCE_DATA
+        struct arch_clocksource_data archdata;
+#endif
+
         const char *name;
         struct list_head list;
         int rating;
-        cycle_t (*vread)(void);
         int (*enable)(struct clocksource *cs);
         void (*disable)(struct clocksource *cs);
         unsigned long flags;