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tools lib: Add for_each_clear_bit macro

Jiri Olsa lkml 1 version New

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  1. v1 Latest0 of 6 patches 0 repliesNew

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Cover letter [PATCH 0/6] tools lib: Add for_each_clear_bit macro
Quoted 11 lines · Jiri Olsa

hi,
sending few perf.data header fixes and adding
two new c2c report options.

Also available in:
git://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
perf/fixes

thanks,
jirka

Quoted 9 lines

---
Jiri Olsa (6):
perf report: Move captured info to generic header info perf header: Display missing features
perf header: Display feature name on write failure perf header: Set nr_numa_nodes only when we parsed all the data perf c2c report: Add --no-source option
perf c2c report: Add --show-all option

oops, forgot to send the initial patch.. it's part of the branch

jirka

---
Adding for_each_clear_bit macro plus all its the necessary backbone functions. Taken from related kernel code. It will be used in following patch.

Link http://lkml.kernel.org/n/[email protected] open here
Signed-off-by Jiri Olsa <[email protected]>
---
 tools/include/asm-generic/bitops.h       |  1 +
 tools/include/asm-generic/bitops/__ffz.h | 12 ++++++++++++
 tools/include/asm-generic/bitops/find.h  | 28 ++++++++++++++++++++++++++++
 tools/include/linux/bitops.h             |  5 +++++
 tools/lib/find_bit.c                     | 25 +++++++++++++++++++++++++
 tools/perf/MANIFEST                      |  1 +
 6 files changed, 72 insertions(+)
 create mode 100644 tools/include/asm-generic/bitops/__ffz.h
tools/include/asm-generic/bitops.h +1 -0
index 653d1bad77de..0304600121da 100644
@@ -13,6 +13,7 @@
  */
 
 #include <asm-generic/bitops/__ffs.h>
+#include <asm-generic/bitops/__ffz.h>
 #include <asm-generic/bitops/fls.h>
 #include <asm-generic/bitops/__fls.h>
 #include <asm-generic/bitops/fls64.h>
tools/include/asm-generic/bitops/__ffz.h new file +12 -0
new file mode 100644
index 000000000000..6744bd4cdf46
@@ -0,0 +1,12 @@
+#ifndef _ASM_GENERIC_BITOPS_FFZ_H_
+#define _ASM_GENERIC_BITOPS_FFZ_H_
+
+/*
+ * ffz - find first zero in word.
+ * @word: The word to search
+ *
+ * Undefined if no zero exists, so code should check against ~0UL first.
+ */
+#define ffz(x)  __ffs(~(x))
+
+#endif /* _ASM_GENERIC_BITOPS_FFZ_H_ */
tools/include/asm-generic/bitops/find.h +28 -0
index 31f51547fcd4..5538ecdc964a 100644
@@ -15,6 +15,21 @@ extern unsigned long find_next_bit(const unsigned long *addr, unsigned long
 		size, unsigned long offset);
 #endif
 
+#ifndef find_next_zero_bit
+
+/**
+ * find_next_zero_bit - find the next cleared bit in a memory region
+ * @addr: The address to base the search on
+ * @offset: The bitnumber to start searching at
+ * @size: The bitmap size in bits
+ *
+ * Returns the bit number of the next zero bit
+ * If no bits are zero, returns @size.
+ */
+unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
+				 unsigned long offset);
+#endif
+
 #ifndef find_first_bit
 
 /**

@@ -30,4 +45,17 @@ extern unsigned long find_first_bit(const unsigned long *addr,
 
 #endif /* find_first_bit */
 
+#ifndef find_first_zero_bit
+
+/**
+ * find_first_zero_bit - find the first cleared bit in a memory region
+ * @addr: The address to start the search at
+ * @size: The maximum number of bits to search
+ *
+ * Returns the bit number of the first cleared bit.
+ * If no bits are zero, returns @size.
+ */
+unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size);
+#endif
+
 #endif /*_TOOLS_LINUX_ASM_GENERIC_BITOPS_FIND_H_ */
tools/include/linux/bitops.h +5 -0
index 49c929a104ee..fc446343ff41 100644
@@ -39,6 +39,11 @@ extern unsigned long __sw_hweight64(__u64 w);
 	     (bit) < (size);					\
 	     (bit) = find_next_bit((addr), (size), (bit) + 1))
 
+#define for_each_clear_bit(bit, addr, size) \
+	for ((bit) = find_first_zero_bit((addr), (size));       \
+	     (bit) < (size);                                    \
+	     (bit) = find_next_zero_bit((addr), (size), (bit) + 1))
+
 /* same as for_each_set_bit() but use bit as value to start with */
 #define for_each_set_bit_from(bit, addr, size) \
 	for ((bit) = find_next_bit((addr), (size), (bit));	\
tools/lib/find_bit.c +25 -0
index 9122a9e80046..6d8b8f22cf55 100644
@@ -82,3 +82,28 @@ unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
 	return size;
 }
 #endif
+
+#ifndef find_first_zero_bit
+/*
+ * Find the first cleared bit in a memory region.
+ */
+unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size)
+{
+	unsigned long idx;
+
+	for (idx = 0; idx * BITS_PER_LONG < size; idx++) {
+		if (addr[idx] != ~0UL)
+			return min(idx * BITS_PER_LONG + ffz(addr[idx]), size);
+	}
+
+	return size;
+}
+#endif
+
+#ifndef find_next_zero_bit
+unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
+				 unsigned long offset)
+{
+	return _find_next_bit(addr, size, offset, ~0UL);
+}
+#endif
tools/perf/MANIFEST +1 -0
index 0bda2cca2b3a..a511e5f31e36 100644
@@ -51,6 +51,7 @@ tools/include/asm-generic/bitops/arch_hweight.h
 tools/include/asm-generic/bitops/atomic.h
 tools/include/asm-generic/bitops/const_hweight.h
 tools/include/asm-generic/bitops/__ffs.h
+tools/include/asm-generic/bitops/__ffz.h
 tools/include/asm-generic/bitops/__fls.h
 tools/include/asm-generic/bitops/find.h
 tools/include/asm-generic/bitops/fls64.h
Signature · 1 line
2.7.4

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