X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=lib%2Flfsr.c;h=1ef6ebbf1a22d39b6a4ff86d936bfebb08e32f96;hb=b57f4fd4e42672f1686fd119da522eace09d1d27;hp=329ef85a8bf7a4e9529838c201482ee0eab78641;hpb=c3afb7639f41e58e44481151e3aa4caa6be789f6;p=fio.git

diff --git a/lib/lfsr.c b/lib/lfsr.c
index 329ef85a..1ef6ebbf 100644
--- a/lib/lfsr.c
+++ b/lib/lfsr.c
@@ -1,5 +1,4 @@
 #include <stdio.h>
-#include <math.h>
 
 #include "lfsr.h"
 #include "../compiler/compiler.h"
@@ -11,7 +10,7 @@
  * The memory overhead of the following tap table should be relatively small,
  * no more than 400 bytes.
  */
-static uint8_t taps[64][FIO_MAX_TAPS] =
+static uint8_t lfsr_taps[64][FIO_MAX_TAPS] =
 {
 	{0}, {0}, {0},		//LFSRs with less that 3-bits cannot exist
 	{3, 2},			//Tap position for 3-bit LFSR
@@ -79,7 +78,7 @@ static uint8_t taps[64][FIO_MAX_TAPS] =
 
 #define __LFSR_NEXT(__fl, __v)						\
 	__v = ((__v >> 1) | __fl->cached_bit) ^			\
-			(((__v & 1UL) - 1UL) & __fl->xormask);
+			(((__v & 1ULL) - 1ULL) & __fl->xormask);
 
 static inline void __lfsr_next(struct fio_lfsr *fl, unsigned int spin)
 {
@@ -89,21 +88,37 @@ static inline void __lfsr_next(struct fio_lfsr *fl, unsigned int spin)
 	 */
 	switch (spin) {
 		case 15: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case 14: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case 13: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case 12: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case 11: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case 10: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case  9: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case  8: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case  7: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case  6: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case  5: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case  4: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case  3: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case  2: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case  1: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		case  0: __LFSR_NEXT(fl, fl->last_val);
+		/* fall through */
 		default: break;
 	}
 }
@@ -124,7 +139,7 @@ static inline void __lfsr_next(struct fio_lfsr *fl, unsigned int spin)
  * c. Check if the calculated value exceeds the desirable range. In this case,
  *    go back to b, else return.
  */
-int lfsr_next(struct fio_lfsr *fl, uint64_t *off, uint64_t last)
+int lfsr_next(struct fio_lfsr *fl, uint64_t *off)
 {
 	if (fl->num_vals++ > fl->max_val)
 		return 1;
@@ -147,7 +162,7 @@ static uint64_t lfsr_create_xormask(uint8_t *taps)
 	uint64_t xormask = 0;
 
 	for(i = 0; i < FIO_MAX_TAPS && taps[i] != 0; i++)
-		xormask |= 1UL << (taps[i] - 1);
+		xormask |= 1ULL << (taps[i] - 1);
 
 	return xormask;
 }
@@ -158,12 +173,12 @@ static uint8_t *find_lfsr(uint64_t size)
 
 	/*
 	 * For an LFSR, there is always a prohibited state (all ones).
-	 * Thus, if we need to find the proper LFSR for our size, we must take that
-	 * into account.
+	 * Thus, if we need to find the proper LFSR for our size, we must
+	 * take that into account.
 	 */
 	for (i = 3; i < 64; i++)
-		if ((1UL << i) > size)
-			return taps[i];
+		if ((1ULL << i) > size)
+			return lfsr_taps[i];
 
 	return NULL;
 }
@@ -217,7 +232,7 @@ static int prepare_spin(struct fio_lfsr *fl, unsigned int spin)
 	return 0;
 }
 
-int lfsr_reset(struct fio_lfsr *fl, unsigned long seed)
+int lfsr_reset(struct fio_lfsr *fl, uint64_t seed)
 {
 	uint64_t bitmask = (fl->cached_bit << 1) - 1;
 
@@ -231,18 +246,18 @@ int lfsr_reset(struct fio_lfsr *fl, unsigned long seed)
 	return 0;
 }
 
-int lfsr_init(struct fio_lfsr *fl, uint64_t nums, unsigned long seed,
-		unsigned int spin)
+int lfsr_init(struct fio_lfsr *fl, uint64_t nums, uint64_t seed,
+	      unsigned int spin)
 {
-	uint8_t *lfsr_taps;
+	uint8_t *taps;
 
-	lfsr_taps = find_lfsr(nums);
-	if (!lfsr_taps)
+	taps = find_lfsr(nums);
+	if (!taps)
 		return 1;
 
 	fl->max_val = nums - 1;
-	fl->xormask = lfsr_create_xormask(lfsr_taps);
-	fl->cached_bit = 1UL << (lfsr_taps[0] - 1);
+	fl->xormask = lfsr_create_xormask(taps);
+	fl->cached_bit = 1ULL << (taps[0] - 1);
 
 	if (prepare_spin(fl, spin))
 		return 1;