alpha: cleanup in bitops.h

Remove 2 functions private to the alpha implemetation,
in favor of similar functions in <linux/log2.h>.

Provide a more efficient version of the fls64 function
for pre-ev67 alphas.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Richard Henderson 2007-05-29 16:01:35 -07:00 committed by Linus Torvalds
parent f54496f55a
commit 74fd1b687f
5 changed files with 73 additions and 24 deletions

View file

@ -7,6 +7,7 @@
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/bootmem.h>
#include <linux/log2.h>
#include <asm/io.h>
#include <asm/hwrpb.h>
@ -53,7 +54,7 @@ size_for_memory(unsigned long max)
{
unsigned long mem = max_low_pfn << PAGE_SHIFT;
if (mem < max)
max = 1UL << ceil_log2(mem);
max = roundup_pow_of_two(mem);
return max;
}

View file

@ -43,6 +43,7 @@
#include <linux/notifier.h>
#include <asm/setup.h>
#include <asm/io.h>
#include <linux/log2.h>
extern struct atomic_notifier_head panic_notifier_list;
static int alpha_panic_event(struct notifier_block *, unsigned long, void *);
@ -1303,7 +1304,7 @@ external_cache_probe(int minsize, int width)
long size = minsize, maxsize = MAX_BCACHE_SIZE * 2;
if (maxsize > (max_low_pfn + 1) << PAGE_SHIFT)
maxsize = 1 << (floor_log2(max_low_pfn + 1) + PAGE_SHIFT);
maxsize = 1 << (ilog2(max_low_pfn + 1) + PAGE_SHIFT);
/* Get the first block cached. */
read_mem_block(__va(0), stride, size);

View file

@ -37,7 +37,8 @@ lib-y = __divqu.o __remqu.o __divlu.o __remlu.o \
$(ev6-y)clear_page.o \
$(ev6-y)copy_page.o \
fpreg.o \
callback_srm.o srm_puts.o srm_printk.o
callback_srm.o srm_puts.o srm_printk.o \
fls.o
lib-$(CONFIG_SMP) += dec_and_lock.o

38
arch/alpha/lib/fls.c Normal file
View file

@ -0,0 +1,38 @@
/*
* arch/alpha/lib/fls.c
*/
#include <linux/module.h>
#include <asm/bitops.h>
/* This is fls(x)-1, except zero is held to zero. This allows most
efficent input into extbl, plus it allows easy handling of fls(0)=0. */
const unsigned char __flsm1_tab[256] =
{
0,
0,
1, 1,
2, 2, 2, 2,
3, 3, 3, 3, 3, 3, 3, 3,
4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
};
EXPORT_SYMBOL(__flsm1_tab);

View file

@ -313,32 +313,29 @@ static inline int ffs(int word)
* fls: find last bit set.
*/
#if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67)
static inline int fls(int word)
static inline int fls64(unsigned long word)
{
return 64 - __kernel_ctlz(word & 0xffffffff);
return 64 - __kernel_ctlz(word);
}
#else
#include <asm-generic/bitops/fls.h>
#endif
#include <asm-generic/bitops/fls64.h>
extern const unsigned char __flsm1_tab[256];
/* Compute powers of two for the given integer. */
static inline long floor_log2(unsigned long word)
static inline int fls64(unsigned long x)
{
#if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67)
return 63 - __kernel_ctlz(word);
#else
long bit;
for (bit = -1; word ; bit++)
word >>= 1;
return bit;
#endif
unsigned long t, a, r;
t = __kernel_cmpbge (x, 0x0101010101010101);
a = __flsm1_tab[t];
t = __kernel_extbl (x, a);
r = a*8 + __flsm1_tab[t] + (x != 0);
return r;
}
#endif
static inline long ceil_log2(unsigned long word)
static inline int fls(int x)
{
long bit = floor_log2(word);
return bit + (word > (1UL << bit));
return fls64((unsigned int) x);
}
/*
@ -353,9 +350,20 @@ static inline unsigned long hweight64(unsigned long w)
return __kernel_ctpop(w);
}
#define hweight32(x) (unsigned int) hweight64((x) & 0xfffffffful)
#define hweight16(x) (unsigned int) hweight64((x) & 0xfffful)
#define hweight8(x) (unsigned int) hweight64((x) & 0xfful)
static inline unsigned int hweight32(unsigned int w)
{
return hweight64(w);
}
static inline unsigned int hweight16(unsigned int w)
{
return hweight64(w & 0xffff);
}
static inline unsigned int hweight8(unsigned int w)
{
return hweight64(w & 0xff);
}
#else
#include <asm-generic/bitops/hweight.h>
#endif