* [parisc-linux] uniline ?
@ 2004-06-06 19:22 Joel Soete
[not found] ` <200407310929.29022.mszick@goquest.com>
0 siblings, 1 reply; 3+ messages in thread
From: Joel Soete @ 2004-06-06 19:22 UTC (permalink / raw)
To: parisc-linux
Hello all,
reading this:
ChangeSet 2004/06/04 16:17:51-07:00, akpm @ osdl.org [diffview]
[PATCH] ia64: uninline find_next_bit on ia64
From: Paul Jackson <pj@sgi.com>
Move the page of code (~700 bytes of instructions) for find_next_bit and
find_next_zero_bit from inline in include/asm-ia64/bitops.h to a real function
in arch/ia64/lib/bitops.c, leaving a declaration and macro wrapper behind.
The other arch's with almost this same code might want to also uninline it:
alpha, parisc, ppc, sh, sparc, sparc64.
These are too big to inline.
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David Mosberger <davidm@hpl.hp.com>
I play to make an equivalent patch for paric:
diff -Naur linux-2.6.a/arch/parisc/lib/bitops.c linux-2.6.b/arch/parisc/lib/bitops.c
--- linux-2.6.a/arch/parisc/lib/bitops.c 2004-06-06 15:16:28.000000000 +0200
+++ linux-2.6.b/arch/parisc/lib/bitops.c 2004-06-06 19:53:09.312540000 +0200
@@ -11,6 +11,7 @@
#include <linux/spinlock.h>
#include <asm/system.h>
#include <asm/atomic.h>
+#include <asm/bitops.h>
#ifdef CONFIG_SMP
atomic_lock_t __atomic_hash[ATOMIC_HASH_SIZE] __lock_aligned = {
@@ -82,3 +83,126 @@
atomic_spin_unlock_irqrestore(ATOMIC_HASH(ptr), flags);
return (unsigned long)prev;
}
+
+/*
+ * This implementation of find_{first,next}_zero_bit was stolen from
+ * Linus' asm-alpha/bitops.h.
+ */
+unsigned long __find_next_zero_bit(void * addr, unsigned long size, unsigned long offset)
+{
+ unsigned long * p = ((unsigned long *) addr) + (offset >> SHIFT_PER_LONG);
+ unsigned long result = offset & ~(BITS_PER_LONG-1);
+ unsigned long tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= (BITS_PER_LONG-1);
+ if (offset) {
+ tmp = *(p++);
+ tmp |= ~0UL >> (BITS_PER_LONG-offset);
+ if (size < BITS_PER_LONG)
+ goto found_first;
+ if (~tmp)
+ goto found_middle;
+ size -= BITS_PER_LONG;
+ result += BITS_PER_LONG;
+ }
+ while (size & ~(BITS_PER_LONG -1)) {
+ if (~(tmp = *(p++)))
+ goto found_middle;
+ result += BITS_PER_LONG;
+ size -= BITS_PER_LONG;
+ }
+ if (!size)
+ return result;
+ tmp = *p;
+found_first:
+ tmp |= ~0UL << size;
+found_middle:
+ return result + ffz(tmp);
+}
+EXPORT_SYMBOL(__find_next_zero_bit);
+
+
+unsigned long __find_next_bit(unsigned long *addr, unsigned long size, unsigned long offset)
+{
+ unsigned long *p = addr + (offset >> 6);
+ unsigned long result = offset & ~(BITS_PER_LONG-1);
+ unsigned long tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= (BITS_PER_LONG-1);
+ if (offset) {
+ tmp = *(p++);
+ tmp &= (~0UL << offset);
+ if (size < BITS_PER_LONG)
+ goto found_first;
+ if (tmp)
+ goto found_middle;
+ size -= BITS_PER_LONG;
+ result += BITS_PER_LONG;
+ }
+ while (size & ~(BITS_PER_LONG-1)) {
+ if ((tmp = *(p++)))
+ goto found_middle;
+ result += BITS_PER_LONG;
+ size -= BITS_PER_LONG;
+ }
+ if (!size)
+ return result;
+ tmp = *p;
+
+found_first:
+ tmp &= (~0UL >> (BITS_PER_LONG - size));
+ if (tmp == 0UL) /* Are any bits set? */
+ return result + size; /* Nope. */
+found_middle:
+ return result + __ffs(tmp);
+}
+EXPORT_SYMBOL(__find_next_bit);
+
+/*
+ * This implementation of ext2_find_{first,next}_zero_bit was stolen from
+ * Linus' asm-alpha/bitops.h and modified for a big-endian machine.
+ */
+
+extern unsigned long __ext2_find_next_zero_bit(void *addr,
+ unsigned long size, unsigned long offset)
+{
+ unsigned int *p = ((unsigned int *) addr) + (offset >> 5);
+ unsigned int result = offset & ~31UL;
+ unsigned int tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= 31UL;
+ if (offset) {
+ tmp = cpu_to_le32p(p++);
+ tmp |= ~0UL >> (32-offset);
+ if (size < 32)
+ goto found_first;
+ if (tmp != ~0U)
+ goto found_middle;
+ size -= 32;
+ result += 32;
+ }
+ while (size >= 32) {
+ if ((tmp = cpu_to_le32p(p++)) != ~0U)
+ goto found_middle;
+ result += 32;
+ size -= 32;
+ }
+ if (!size)
+ return result;
+ tmp = cpu_to_le32p(p);
+found_first:
+ tmp |= ~0U << size;
+found_middle:
+ return result + ffz(tmp);
+}
+EXPORT_SYMBOL(__ext2_find_next_zero_bit);
+
diff -Naur linux-2.6.a/include/asm-parisc/bitops.h linux-2.6.b/include/asm-parisc/bitops.h
--- linux-2.6.a/include/asm-parisc/bitops.h 2004-06-06 15:17:31.000000000 +0200
+++ linux-2.6.b/include/asm-parisc/bitops.h 2004-06-06 19:53:20.232540000 +0200
@@ -354,78 +354,15 @@
#define find_first_zero_bit(addr, size) \
find_next_zero_bit((addr), (size), 0)
-static __inline__ unsigned long find_next_zero_bit(void * addr, unsigned long size, unsigned long offset)
-{
- unsigned long * p = ((unsigned long *) addr) + (offset >> SHIFT_PER_LONG);
- unsigned long result = offset & ~(BITS_PER_LONG-1);
-
- if (offset >= size)
- return size;
- size -= result;
- offset &= (BITS_PER_LONG-1);
- if (offset) {
- tmp = *(p++);
- tmp |= ~0UL >> (BITS_PER_LONG-offset);
- if (size < BITS_PER_LONG)
- goto found_first;
- if (~tmp)
- goto found_middle;
- size -= BITS_PER_LONG;
- result += BITS_PER_LONG;
- }
- while (size & ~(BITS_PER_LONG -1)) {
- if (~(tmp = *(p++)))
- goto found_middle;
- result += BITS_PER_LONG;
- size -= BITS_PER_LONG;
- }
- if (!size)
- return result;
- tmp = *p;
-found_first:
- tmp |= ~0UL << size;
-found_middle:
- return result + ffz(tmp);
-}
+#define find_next_zero_bit(addr, size, offset) \
+ __find_next_zero_bit((addr), (size), (offset))
-static __inline__ unsigned long find_next_bit(unsigned long *addr, unsigned long size, unsigned long offset)
-{
- unsigned long *p = addr + (offset >> 6);
- unsigned long result = offset & ~(BITS_PER_LONG-1);
- unsigned long tmp;
-
- if (offset >= size)
- return size;
- size -= result;
- offset &= (BITS_PER_LONG-1);
- if (offset) {
- tmp = *(p++);
- tmp &= (~0UL << offset);
- if (size < BITS_PER_LONG)
- goto found_first;
- if (tmp)
- goto found_middle;
- size -= BITS_PER_LONG;
- result += BITS_PER_LONG;
- }
- while (size & ~(BITS_PER_LONG-1)) {
- if ((tmp = *(p++)))
- goto found_middle;
- result += BITS_PER_LONG;
- size -= BITS_PER_LONG;
- }
- if (!size)
- return result;
- tmp = *p;
-
-found_first:
- tmp &= (~0UL >> (BITS_PER_LONG - size));
- if (tmp == 0UL) /* Are any bits set? */
- return result + size; /* Nope. */
-found_middle:
- return result + __ffs(tmp);
-}
+extern unsigned long __find_next_zero_bit(void * addr, unsigned long size, unsigned long offset);
+
+#define find_next_bit(addr, size, offset) \
+ __find_next_bit((addr), (size), (offset))
+
+extern unsigned long __find_next_bit(unsigned long *addr, unsigned long size, unsigned long offset);
/**
* find_first_bit - find the first set bit in a memory region
@@ -474,41 +411,10 @@
#define ext2_find_first_zero_bit(addr, size) \
ext2_find_next_zero_bit((addr), (size), 0)
-extern __inline__ unsigned long ext2_find_next_zero_bit(void *addr,
- unsigned long size, unsigned long offset)
-{
- unsigned int *p = ((unsigned int *) addr) + (offset >> 5);
- unsigned int result = offset & ~31UL;
- unsigned int tmp;
-
- if (offset >= size)
- return size;
- size -= result;
- offset &= 31UL;
- if (offset) {
- tmp = cpu_to_le32p(p++);
- tmp |= ~0UL >> (32-offset);
- if (size < 32)
- goto found_first;
- if (tmp != ~0U)
- goto found_middle;
- size -= 32;
- result += 32;
- }
- while (size >= 32) {
- if ((tmp = cpu_to_le32p(p++)) != ~0U)
- goto found_middle;
- result += 32;
- size -= 32;
- }
- if (!size)
- return result;
- tmp = cpu_to_le32p(p);
-found_first:
- tmp |= ~0U << size;
-found_middle:
- return result + ffz(tmp);
-}
+#define ext2_find_next_zero_bit(addr, size, offset) \
+ __ext2_find_next_zero_bit((addr), (size), (offset))
+
+extern unsigned long __ext2_find_next_zero_bit(void *addr, unsigned long size, unsigned long offset);
/* Bitmap functions for the minix filesystem. */
#define minix_test_and_set_bit(nr,addr) ext2_set_bit(nr,addr)
========><======
What's your opinion about its relievence for parisc?
hth,
Joel
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parisc-linux@lists.parisc-linux.org
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^ permalink raw reply [flat|nested] 3+ messages in thread[parent not found: <200407310929.29022.mszick@goquest.com>]
[parent not found: <1091293141.1920.34.camel@mulgrave>]
* Re: [parisc-linux] uninline in bitops.c as ia64 or sparc64? [not found] ` <1091293141.1920.34.camel@mulgrave> @ 2004-08-09 14:54 ` Michael S. Zick 2004-08-09 17:15 ` Michael S. Zick 0 siblings, 1 reply; 3+ messages in thread From: Michael S. Zick @ 2004-08-09 14:54 UTC (permalink / raw) To: James Bottomley; +Cc: PARISC list [-- Attachment #1: Type: text/plain, Size: 3351 bytes --] On Sat July 31 2004 11:58, James Bottomley wrote: > On Sat, 2004-07-31 at 10:29, Michael S. Zick wrote: > > How about a different algorithm? > > Say:: 3 * Log_2 (Register Size) > > This algorithm is a more complex form of generic_ffz() in linux/bitops.h > > perhaps we should use generic_ffz as the basis for this? > generic_ffz is defined as integer - is 'integer' the same size cpu32 and cpu64? If not, that routine needs a size-conditional test for the other 32 bits on cpu64. Here is a suggested fix for include/asm-parisc/bitops.h - NOTE 1: I have no way to test this - some needs to check my work. NOTE 2: I did try to do this on (electronic) pencil and paper - You can get the pictures at: <www.goquest.com/~mszick> as: hpbitfinder.ps.bz2 NOTE 3: Same diff is attached as in-lined, just in case my mail agent trashes it. Mike Index: include/asm-parisc/bitops.h =================================================================== RCS file: /opt/lib/cvs/parisc/include/asm-parisc/bitops.h,v retrieving revision 1.1.1.1 diff -u -3 -p -r1.1.1.1 bitops.h --- a/include/asm-parisc/bitops.h 13 Jul 2004 05:40:29 -0000 1.1.1.1 +++ b/include/asm-parisc/bitops.h 9 Aug 2004 14:33:03 -0000 @@ -217,11 +217,16 @@ static __inline__ int test_bit(int nr, c * * This algorithm avoids branches by making use of nullification. * One side effect of "extr" instructions is it sets PSW[N] bit. - * How PSW[N] (nullify next insn) gets set is determined by the + * How PSW[N] (nullify next insn) gets set is determined by the * "condition" field (eg "<>" or "TR" below) in the extr* insn. * Only the 1st and one of either the 2cd or 3rd insn will get executed. * Each set of 3 insn will get executed in 2 cycles on PA8x00 vs 16 or so * cycles for each mispredicted branch. + * + * Provide either a u64 or u32 version based on cpu register size. + * Note that the hard coded field indexes depend on cpu register size; + * and the extract instruction generates a right-justified result. + * The index numbers are hp-bit-position not radix 2 numbers. <msz> */ static __inline__ unsigned long __ffs(unsigned long x) @@ -229,14 +234,27 @@ static __inline__ unsigned long __ffs(un unsigned long ret; __asm__( -#if BITS_PER_LONG > 32 +#ifdef __LP64__ " ldi 63,%1\n" " extrd,u,*<> %0,63,32,%%r0\n" " extrd,u,*TR %0,31,32,%0\n" /* move top 32-bits down */ " addi -32,%1,%1\n" + " extrd,u,*<> %0,63,16,%%r0\n" + " extrd,u,*TR %0,47,16,%0\n" /* xxxx0000 -> 0000xxxx */ + " addi -16,%1,%1\n" + " extrd,u,*<> %0,63,8,%%r0\n" + " extrd,u,*TR %0,55,8,%0\n" /* 0000xx00 -> 000000xx */ + " addi -8,%1,%1\n" + " extrd,u,*<> %0,63,4,%%r0\n" + " extrd,u,*TR %0,59,4,%0\n" /* 000000x0 -> 0000000x */ + " addi -4,%1,%1\n" + " extrd,u,*<> %0,63,2,%%r0\n" + " extrd,u,*TR %0,61,2,%0\n" /* 0000000y, 1100b -> 0011b */ + " addi -2,%1,%1\n" + " extrd,u,*= %0,63,1,%%r0\n" /* check last bit */ + " addi -1,%1,%1\n" #else " ldi 31,%1\n" -#endif " extru,<> %0,31,16,%%r0\n" " extru,TR %0,15,16,%0\n" /* xxxx0000 -> 0000xxxx */ " addi -16,%1,%1\n" @@ -251,6 +269,7 @@ static __inline__ unsigned long __ffs(un " addi -2,%1,%1\n" " extru,= %0,31,1,%%r0\n" /* check last bit */ " addi -1,%1,%1\n" +#endif : "+r" (x), "=r" (ret) ); return ret; } [-- Attachment #2: bitops.h.diff.bz2 --] [-- Type: application/x-bzip2, Size: 1171 bytes --] [-- Attachment #3: Type: text/plain, Size: 169 bytes --] _______________________________________________ parisc-linux mailing list parisc-linux@lists.parisc-linux.org http://lists.parisc-linux.org/mailman/listinfo/parisc-linux ^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [parisc-linux] uninline in bitops.c as ia64 or sparc64? 2004-08-09 14:54 ` [parisc-linux] uninline in bitops.c as ia64 or sparc64? Michael S. Zick @ 2004-08-09 17:15 ` Michael S. Zick 0 siblings, 0 replies; 3+ messages in thread From: Michael S. Zick @ 2004-08-09 17:15 UTC (permalink / raw) To: parisc-linux On Mon August 9 2004 09:54, Michael S. Zick wrote: > ------- > > Mike > > Index: include/asm-parisc/bitops.h > =================================================================== > RCS file: /opt/lib/cvs/parisc/include/asm-parisc/bitops.h,v > retrieving revision 1.1.1.1 > diff -u -3 -p -r1.1.1.1 bitops.h Sorry for the self-reply... If compiled with 32-bit compiler the NOT(__LP64__) path will compile. If the resultant program is loaded on a 64-bit machine running 'narrow mode'; it will fail. Since the mode bit only changes the addressing not the bit-position numbering.(1) Translation: As submitted, it should compile for 64-bit and run 64-Wide; it should compile for 32-bit and run 32-bit. It is only the case of compiling for 32-bit and then trying to run it on a 64-bit machine in narrow mode that should fail. I'll work on this - I probably will abuse the shift-right-double instruction to come up with a compiles correctly, runs anywhere version. Two other problems I am considering: 1) It only beats on two (not counting GR0) registers; it will probably cause register stalls on pipelined machines. 2) It is bigger than a cache line, probably executes in less than a memory cycle - so it will probably 'starve' the cpu; waiting for the next memory cycle to fill the next i-cache line. Taken all together - an interesting problem. Mike (1) Does 32-bit gcc ever generate extract/deposit? This might cause problems running anything 32-bit on 64-bit-narrow. _______________________________________________ parisc-linux mailing list parisc-linux@lists.parisc-linux.org http://lists.parisc-linux.org/mailman/listinfo/parisc-linux ^ permalink raw reply [flat|nested] 3+ messages in thread
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2004-06-06 19:22 [parisc-linux] uniline ? Joel Soete
[not found] ` <200407310929.29022.mszick@goquest.com>
[not found] ` <1091293141.1920.34.camel@mulgrave>
2004-08-09 14:54 ` [parisc-linux] uninline in bitops.c as ia64 or sparc64? Michael S. Zick
2004-08-09 17:15 ` Michael S. Zick
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