[73/90] sparc: Use popc when possible for ffs/__ffs/ffz.
From: Greg KH
Date: Sun Aug 14 2011 - 12:13:57 EST
3.0-stable review patch. If anyone has any objections, please let us know.
------------------
From: "David S. Miller" <davem@xxxxxxxxxxxxx>
[ Upstream commit 56d205cc5c0a3032a605121d4253e111193bf923 ]
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
arch/sparc/include/asm/bitops_64.h | 7 +--
arch/sparc/kernel/entry.h | 7 +++
arch/sparc/kernel/setup_64.c | 34 +++++++++-----
arch/sparc/kernel/sparc_ksyms_64.c | 4 +
arch/sparc/kernel/vmlinux.lds.S | 5 ++
arch/sparc/lib/Makefile | 2
arch/sparc/lib/ffs.S | 84 +++++++++++++++++++++++++++++++++++++
7 files changed, 127 insertions(+), 16 deletions(-)
create mode 100644 arch/sparc/lib/ffs.S
--- a/arch/sparc/include/asm/bitops_64.h
+++ b/arch/sparc/include/asm/bitops_64.h
@@ -26,16 +26,17 @@ extern void change_bit(unsigned long nr,
#define smp_mb__before_clear_bit() barrier()
#define smp_mb__after_clear_bit() barrier()
-#include <asm-generic/bitops/ffz.h>
-#include <asm-generic/bitops/__ffs.h>
#include <asm-generic/bitops/fls.h>
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/fls64.h>
#ifdef __KERNEL__
+extern int ffs(int x);
+extern unsigned long __ffs(unsigned long);
+
+#include <asm-generic/bitops/ffz.h>
#include <asm-generic/bitops/sched.h>
-#include <asm-generic/bitops/ffs.h>
/*
* hweightN: returns the hamming weight (i.e. the number
--- a/arch/sparc/kernel/entry.h
+++ b/arch/sparc/kernel/entry.h
@@ -49,6 +49,13 @@ struct popc_3insn_patch_entry {
extern struct popc_3insn_patch_entry __popc_3insn_patch,
__popc_3insn_patch_end;
+struct popc_6insn_patch_entry {
+ unsigned int addr;
+ unsigned int insns[6];
+};
+extern struct popc_6insn_patch_entry __popc_6insn_patch,
+ __popc_6insn_patch_end;
+
extern void __init per_cpu_patch(void);
extern void __init sun4v_patch(void);
extern void __init boot_cpu_id_too_large(int cpu);
--- a/arch/sparc/kernel/setup_64.c
+++ b/arch/sparc/kernel/setup_64.c
@@ -275,25 +275,35 @@ void __init sun4v_patch(void)
static void __init popc_patch(void)
{
struct popc_3insn_patch_entry *p3;
+ struct popc_6insn_patch_entry *p6;
p3 = &__popc_3insn_patch;
while (p3 < &__popc_3insn_patch_end) {
- unsigned long addr = p3->addr;
+ unsigned long i, addr = p3->addr;
- *(unsigned int *) (addr + 0) = p3->insns[0];
- wmb();
- __asm__ __volatile__("flush %0" : : "r" (addr + 0));
-
- *(unsigned int *) (addr + 4) = p3->insns[1];
- wmb();
- __asm__ __volatile__("flush %0" : : "r" (addr + 4));
-
- *(unsigned int *) (addr + 8) = p3->insns[2];
- wmb();
- __asm__ __volatile__("flush %0" : : "r" (addr + 4));
+ for (i = 0; i < 3; i++) {
+ *(unsigned int *) (addr + (i * 4)) = p3->insns[i];
+ wmb();
+ __asm__ __volatile__("flush %0"
+ : : "r" (addr + (i * 4)));
+ }
p3++;
}
+
+ p6 = &__popc_6insn_patch;
+ while (p6 < &__popc_6insn_patch_end) {
+ unsigned long i, addr = p6->addr;
+
+ for (i = 0; i < 6; i++) {
+ *(unsigned int *) (addr + (i * 4)) = p6->insns[i];
+ wmb();
+ __asm__ __volatile__("flush %0"
+ : : "r" (addr + (i * 4)));
+ }
+
+ p6++;
+ }
}
#ifdef CONFIG_SMP
--- a/arch/sparc/kernel/sparc_ksyms_64.c
+++ b/arch/sparc/kernel/sparc_ksyms_64.c
@@ -45,5 +45,9 @@ EXPORT_SYMBOL(__arch_hweight16);
EXPORT_SYMBOL(__arch_hweight32);
EXPORT_SYMBOL(__arch_hweight64);
+/* from ffs_ffz.S */
+EXPORT_SYMBOL(ffs);
+EXPORT_SYMBOL(__ffs);
+
/* Exporting a symbol from /init/main.c */
EXPORT_SYMBOL(saved_command_line);
--- a/arch/sparc/kernel/vmlinux.lds.S
+++ b/arch/sparc/kernel/vmlinux.lds.S
@@ -112,6 +112,11 @@ SECTIONS
*(.popc_3insn_patch)
__popc_3insn_patch_end = .;
}
+ .popc_6insn_patch : {
+ __popc_6insn_patch = .;
+ *(.popc_6insn_patch)
+ __popc_6insn_patch_end = .;
+ }
PERCPU_SECTION(SMP_CACHE_BYTES)
. = ALIGN(PAGE_SIZE);
--- a/arch/sparc/lib/Makefile
+++ b/arch/sparc/lib/Makefile
@@ -37,7 +37,7 @@ lib-$(CONFIG_SPARC64) += GENmemcpy.o GEN
lib-$(CONFIG_SPARC64) += GENpatch.o GENpage.o GENbzero.o
lib-$(CONFIG_SPARC64) += copy_in_user.o user_fixup.o memmove.o
-lib-$(CONFIG_SPARC64) += mcount.o ipcsum.o xor.o hweight.o
+lib-$(CONFIG_SPARC64) += mcount.o ipcsum.o xor.o hweight.o ffs.o
obj-y += iomap.o
obj-$(CONFIG_SPARC32) += atomic32.o
--- /dev/null
+++ b/arch/sparc/lib/ffs.S
@@ -0,0 +1,84 @@
+#include <linux/linkage.h>
+
+ .register %g2,#scratch
+
+ .text
+ .align 32
+
+ENTRY(ffs)
+ brnz,pt %o0, 1f
+ mov 1, %o1
+ retl
+ clr %o0
+ nop
+ nop
+ENTRY(__ffs)
+ sllx %o0, 32, %g1 /* 1 */
+ srlx %o0, 32, %g2
+
+ clr %o1 /* 2 */
+ movrz %g1, %g2, %o0
+
+ movrz %g1, 32, %o1 /* 3 */
+1: clr %o2
+
+ sllx %o0, (64 - 16), %g1 /* 4 */
+ srlx %o0, 16, %g2
+
+ movrz %g1, %g2, %o0 /* 5 */
+ clr %o3
+
+ movrz %g1, 16, %o2 /* 6 */
+ clr %o4
+
+ and %o0, 0xff, %g1 /* 7 */
+ srlx %o0, 8, %g2
+
+ movrz %g1, %g2, %o0 /* 8 */
+ clr %o5
+
+ movrz %g1, 8, %o3 /* 9 */
+ add %o2, %o1, %o2
+
+ and %o0, 0xf, %g1 /* 10 */
+ srlx %o0, 4, %g2
+
+ movrz %g1, %g2, %o0 /* 11 */
+ add %o2, %o3, %o2
+
+ movrz %g1, 4, %o4 /* 12 */
+
+ and %o0, 0x3, %g1 /* 13 */
+ srlx %o0, 2, %g2
+
+ movrz %g1, %g2, %o0 /* 14 */
+ add %o2, %o4, %o2
+
+ movrz %g1, 2, %o5 /* 15 */
+
+ and %o0, 0x1, %g1 /* 16 */
+
+ add %o2, %o5, %o2 /* 17 */
+ xor %g1, 0x1, %g1
+
+ retl /* 18 */
+ add %o2, %g1, %o0
+ENDPROC(ffs)
+ENDPROC(__ffs)
+
+ .section .popc_6insn_patch, "ax"
+ .word ffs
+ brz,pn %o0, 98f
+ neg %o0, %g1
+ xnor %o0, %g1, %o1
+ popc %o1, %o0
+98: retl
+ nop
+ .word __ffs
+ neg %o0, %g1
+ xnor %o0, %g1, %o1
+ popc %o1, %o0
+ retl
+ sub %o0, 1, %o0
+ nop
+ .previous
--
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