[S390] hwsampler: Set a sane default sampling rate

The sampling interval for the hardware sampler is specified in cycles.
(see SA23-2260-01 The Load-Program-Parameter and the CPU-Measurement
Facilities)
The current default value will therefore result in millions of samples.
This patch changes the default sampling interval to 4M, which will
result in ~1500 samples per second on a z196 reducing the overhead
of sampling.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/oprofile/init.c

@@ -25,7 +25,7 @@ extern void s390_backtrace(struct pt_regs * const regs, unsigned int depth);
 
 #include "hwsampler.h"
 
-#define DEFAULT_INTERVAL	4096
+#define DEFAULT_INTERVAL	4127518
 
 #define DEFAULT_SDBT_BLOCKS	1
 #define DEFAULT_SDB_BLOCKS	511