From: Jens Axboe <jens.axboe@oracle.com>
Date: Sun, 1 Jun 2008 17:45:10 +0000 (+0200)
Subject: Readd the arch ffz functions
X-Git-Tag: fio-1.21-rc4~10
X-Git-Url: https://git.kernel.dk/?p=fio.git;a=commitdiff_plain;h=8f7e39dd35a40d088a31f33f12402a1eaf31b2c4

Readd the arch ffz functions

May as well use the single op version if we have them, it's
generally a lot faster than the generic_ffz()

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---

diff --git a/arch/arch-ia64.h b/arch/arch-ia64.h
index 9c8b406c..6dd8196d 100644
--- a/arch/arch-ia64.h
+++ b/arch/arch-ia64.h
@@ -21,4 +21,17 @@
 #define nop		asm volatile ("hint @pause" ::: "memory");
 #define read_barrier()	asm volatile ("mf" ::: "memory")
 
+#define ia64_popcnt(x)							\
+({									\
+	unsigned long ia64_intri_res;					\
+	asm ("popcnt %0=%1" : "=r" (ia64_intri_res) : "r" (x));		\
+	ia64_intri_res;							\
+})
+
+static inline unsigned long arch_ffz(unsigned long bitmask)
+{
+	return ia64_popcnt(bitmask & (~bitmask - 1));
+}
+#define ARCH_HAVE_FFZ
+
 #endif
diff --git a/arch/arch-ppc.h b/arch/arch-ppc.h
index 4d771052..6256d056 100644
--- a/arch/arch-ppc.h
+++ b/arch/arch-ppc.h
@@ -28,4 +28,20 @@
 	__asm__ __volatile__ ("sync" : : : "memory")
 #endif
 
+static inline int __ilog2(unsigned long bitmask)
+{
+	int lz;
+
+	asm ("cntlzw %0,%1" : "=r" (lz) : "r" (bitmask));
+	return 31 - lz;
+}
+
+static inline int arch_ffz(unsigned long bitmask)
+{
+	if ((bitmask = ~bitmask) == 0)
+		return 32;
+	return  __ilog2(bitmask & -bitmask);
+}
+#define ARCH_HAVE_FFZ
+
 #endif
diff --git a/arch/arch-x86.h b/arch/arch-x86.h
index 4d7ea49d..a396c850 100644
--- a/arch/arch-x86.h
+++ b/arch/arch-x86.h
@@ -32,4 +32,11 @@
 #define nop		__asm__ __volatile__("rep;nop": : :"memory")
 #define read_barrier()	asm volatile ("": : :"memory")
 
+static inline unsigned long arch_ffz(unsigned long bitmask)
+{
+	__asm__("bsfl %1,%0" :"=r" (bitmask) :"r" (~bitmask));
+	return bitmask;
+}
+#define ARCH_HAVE_FFZ
+
 #endif
diff --git a/arch/arch-x86_64.h b/arch/arch-x86_64.h
index b49fd5f1..972c623a 100644
--- a/arch/arch-x86_64.h
+++ b/arch/arch-x86_64.h
@@ -32,4 +32,11 @@
 #define nop		__asm__ __volatile__("rep;nop": : :"memory")
 #define read_barrier()	asm volatile("lfence":::"memory")
 
+static inline unsigned long arch_ffz(unsigned long bitmask)
+{
+	__asm__("bsfq %1,%0" :"=r" (bitmask) :"r" (~bitmask));
+	return bitmask;
+}
+#define ARCH_HAVE_FFZ
+
 #endif
diff --git a/arch/arch.h b/arch/arch.h
index 8d06c911..f4eb855e 100644
--- a/arch/arch.h
+++ b/arch/arch.h
@@ -32,4 +32,10 @@ enum {
 #error "Unsupported arch"
 #endif
 
+#ifdef ARCH_HAVE_FFZ
+#define ffz(bitmask)	arch_ffz(bitmask)
+#else
+#include "../lib/ffz.h"
+#endif
+
 #endif
diff --git a/io_u.c b/io_u.c
index a6d1f1d0..c662470a 100644
--- a/io_u.c
+++ b/io_u.c
@@ -7,7 +7,6 @@
 
 #include "fio.h"
 #include "hash.h"
-#include "lib/ffz.h"
 
 /*
  * Change this define to play with the timeout handling