Merge tag 'perf-core-for-mingo-2' of git://git.kernel.org/pub/scm/lin…

…ux/kernel/git/acme/linux into perf/urgent

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

User visible changes:

- The mmap address range for the ring buffer now is calculated using the
  contents of /proc/sys/kernel/perf_event_mlock_kb.

  This fixes an -EPERM case where 'trace' was trying to use more than what
  is configured on perf_event_mlock_kb. (Arnaldo Carvalho de Melo)

Infrastructure changes:

- Move bitops definitions so that they match the header file hierarchy
  in the kernel sources where that code came from. (Arnaldo Carvalho de Melo)

- Adopt round{down,up}_pow_of_two from the kernel and use it instead of
  equivalent code, so that we reuse more kernel code and make tools/ look
  more like kernel source code, to encourage further contributions from
  kernel hackers (Arnaldo Carvalho de Melo)

- Fix use after free in filename__read_build_id (Mitchell Krome)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

tools/include/asm-generic/bitops.h

@@ -0,0 +1,27 @@
+#ifndef __TOOLS_ASM_GENERIC_BITOPS_H
+#define __TOOLS_ASM_GENERIC_BITOPS_H
+
+/*
+ * tools/ copied this from include/asm-generic/bitops.h, bit by bit as it needed
+ * some functions.
+ *
+ * For the benefit of those who are trying to port Linux to another
+ * architecture, here are some C-language equivalents.  You should
+ * recode these in the native assembly language, if at all possible.
+ *
+ * C language equivalents written by Theodore Ts'o, 9/26/92
+ */
+
+#include <asm-generic/bitops/__ffs.h>
+#include <asm-generic/bitops/fls.h>
+#include <asm-generic/bitops/__fls.h>
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/find.h>
+
+#ifndef _TOOLS_LINUX_BITOPS_H_
+#error only <linux/bitops.h> can be included directly
+#endif
+
+#include <asm-generic/bitops/atomic.h>
+
+#endif /* __TOOLS_ASM_GENERIC_BITOPS_H */

tools/include/asm-generic/bitops/__ffs.h

@@ -0,0 +1,43 @@
+#ifndef _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_
+#define _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_
+
+#include <asm/types.h>
+
+/**
+ * __ffs - find first bit in word.
+ * @word: The word to search
+ *
+ * Undefined if no bit exists, so code should check against 0 first.
+ */
+static __always_inline unsigned long __ffs(unsigned long word)
+{
+	int num = 0;
+
+#if __BITS_PER_LONG == 64
+	if ((word & 0xffffffff) == 0) {
+		num += 32;
+		word >>= 32;
+	}
+#endif
+	if ((word & 0xffff) == 0) {
+		num += 16;
+		word >>= 16;
+	}
+	if ((word & 0xff) == 0) {
+		num += 8;
+		word >>= 8;
+	}
+	if ((word & 0xf) == 0) {
+		num += 4;
+		word >>= 4;
+	}
+	if ((word & 0x3) == 0) {
+		num += 2;
+		word >>= 2;
+	}
+	if ((word & 0x1) == 0)
+		num += 1;
+	return num;
+}
+
+#endif /* _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_ */

tools/include/asm-generic/bitops/__fls.h

@@ -0,0 +1 @@
+#include <../../../../include/asm-generic/bitops/__fls.h>

tools/include/asm-generic/bitops/atomic.h

@@ -0,0 +1,22 @@
+#ifndef _TOOLS_LINUX_ASM_GENERIC_BITOPS_ATOMIC_H_
+#define _TOOLS_LINUX_ASM_GENERIC_BITOPS_ATOMIC_H_
+
+#include <asm/types.h>
+
+static inline void set_bit(int nr, unsigned long *addr)
+{
+	addr[nr / __BITS_PER_LONG] |= 1UL << (nr % __BITS_PER_LONG);
+}
+
+static inline void clear_bit(int nr, unsigned long *addr)
+{
+	addr[nr / __BITS_PER_LONG] &= ~(1UL << (nr % __BITS_PER_LONG));
+}
+
+static __always_inline int test_bit(unsigned int nr, const unsigned long *addr)
+{
+	return ((1UL << (nr % __BITS_PER_LONG)) &
+		(((unsigned long *)addr)[nr / __BITS_PER_LONG])) != 0;
+}
+
+#endif /* _TOOLS_LINUX_ASM_GENERIC_BITOPS_ATOMIC_H_ */

tools/include/asm-generic/bitops/find.h

@@ -0,0 +1,33 @@
+#ifndef _TOOLS_LINUX_ASM_GENERIC_BITOPS_FIND_H_
+#define _TOOLS_LINUX_ASM_GENERIC_BITOPS_FIND_H_
+
+#ifndef find_next_bit
+/**
+ * find_next_bit - find the next set 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 for the next set bit
+ * If no bits are set, returns @size.
+ */
+extern unsigned long find_next_bit(const unsigned long *addr, unsigned long
+		size, unsigned long offset);
+#endif
+
+#ifndef find_first_bit
+
+/**
+ * find_first_bit - find the first set 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 set bit.
+ * If no bits are set, returns @size.
+ */
+extern unsigned long find_first_bit(const unsigned long *addr,
+				    unsigned long size);
+
+#endif /* find_first_bit */
+
+#endif /*_TOOLS_LINUX_ASM_GENERIC_BITOPS_FIND_H_ */

tools/include/asm-generic/bitops/fls.h

@@ -0,0 +1 @@
+#include <../../../../include/asm-generic/bitops/fls.h>

tools/include/asm-generic/bitops/fls64.h

@@ -0,0 +1 @@
+#include <../../../../include/asm-generic/bitops/fls64.h>

tools/include/linux/bitops.h

@@ -0,0 +1,53 @@
+#ifndef _TOOLS_LINUX_BITOPS_H_
+#define _TOOLS_LINUX_BITOPS_H_
+
+#include <linux/kernel.h>
+#include <linux/compiler.h>
+#include <asm/hweight.h>
+
+#ifndef __WORDSIZE
+#define __WORDSIZE (__SIZEOF_LONG__ * 8)
+#endif
+
+#define BITS_PER_LONG __WORDSIZE
+
+#define BIT_MASK(nr)		(1UL << ((nr) % BITS_PER_LONG))
+#define BIT_WORD(nr)		((nr) / BITS_PER_LONG)
+#define BITS_PER_BYTE		8
+#define BITS_TO_LONGS(nr)	DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
+#define BITS_TO_U64(nr)		DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u64))
+#define BITS_TO_U32(nr)		DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u32))
+#define BITS_TO_BYTES(nr)	DIV_ROUND_UP(nr, BITS_PER_BYTE)
+
+/*
+ * Include this here because some architectures need generic_ffs/fls in
+ * scope
+ *
+ * XXX: this needs to be asm/bitops.h, when we get to per arch optimizations
+ */
+#include <asm-generic/bitops.h>
+
+#define for_each_set_bit(bit, addr, size) \
+	for ((bit) = find_first_bit((addr), (size));		\
+	     (bit) < (size);					\
+	     (bit) = find_next_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));	\
+	     (bit) < (size);					\
+	     (bit) = find_next_bit((addr), (size), (bit) + 1))
+
+static inline unsigned long hweight_long(unsigned long w)
+{
+	return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
+}
+
+static inline unsigned fls_long(unsigned long l)
+{
+	if (sizeof(l) == 4)
+		return fls(l);
+	return fls64(l);
+}
+
+#endif

tools/include/linux/log2.h

@@ -0,0 +1,185 @@
+/* Integer base 2 logarithm calculation
+ *
+ * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _TOOLS_LINUX_LOG2_H
+#define _TOOLS_LINUX_LOG2_H
+
+/*
+ * deal with unrepresentable constant logarithms
+ */
+extern __attribute__((const, noreturn))
+int ____ilog2_NaN(void);
+
+/*
+ * non-constant log of base 2 calculators
+ * - the arch may override these in asm/bitops.h if they can be implemented
+ *   more efficiently than using fls() and fls64()
+ * - the arch is not required to handle n==0 if implementing the fallback
+ */
+static inline __attribute__((const))
+int __ilog2_u32(u32 n)
+{
+	return fls(n) - 1;
+}
+
+static inline __attribute__((const))
+int __ilog2_u64(u64 n)
+{
+	return fls64(n) - 1;
+}
+
+/*
+ *  Determine whether some value is a power of two, where zero is
+ * *not* considered a power of two.
+ */
+
+static inline __attribute__((const))
+bool is_power_of_2(unsigned long n)
+{
+	return (n != 0 && ((n & (n - 1)) == 0));
+}
+
+/*
+ * round up to nearest power of two
+ */
+static inline __attribute__((const))
+unsigned long __roundup_pow_of_two(unsigned long n)
+{
+	return 1UL << fls_long(n - 1);
+}
+
+/*
+ * round down to nearest power of two
+ */
+static inline __attribute__((const))
+unsigned long __rounddown_pow_of_two(unsigned long n)
+{
+	return 1UL << (fls_long(n) - 1);
+}
+
+/**
+ * ilog2 - log of base 2 of 32-bit or a 64-bit unsigned value
+ * @n - parameter
+ *
+ * constant-capable log of base 2 calculation
+ * - this can be used to initialise global variables from constant data, hence
+ *   the massive ternary operator construction
+ *
+ * selects the appropriately-sized optimised version depending on sizeof(n)
+ */
+#define ilog2(n)				\
+(						\
+	__builtin_constant_p(n) ? (		\
+		(n) < 1 ? ____ilog2_NaN() :	\
+		(n) & (1ULL << 63) ? 63 :	\
+		(n) & (1ULL << 62) ? 62 :	\
+		(n) & (1ULL << 61) ? 61 :	\
+		(n) & (1ULL << 60) ? 60 :	\
+		(n) & (1ULL << 59) ? 59 :	\
+		(n) & (1ULL << 58) ? 58 :	\
+		(n) & (1ULL << 57) ? 57 :	\
+		(n) & (1ULL << 56) ? 56 :	\
+		(n) & (1ULL << 55) ? 55 :	\
+		(n) & (1ULL << 54) ? 54 :	\
+		(n) & (1ULL << 53) ? 53 :	\
+		(n) & (1ULL << 52) ? 52 :	\
+		(n) & (1ULL << 51) ? 51 :	\
+		(n) & (1ULL << 50) ? 50 :	\
+		(n) & (1ULL << 49) ? 49 :	\
+		(n) & (1ULL << 48) ? 48 :	\
+		(n) & (1ULL << 47) ? 47 :	\
+		(n) & (1ULL << 46) ? 46 :	\
+		(n) & (1ULL << 45) ? 45 :	\
+		(n) & (1ULL << 44) ? 44 :	\
+		(n) & (1ULL << 43) ? 43 :	\
+		(n) & (1ULL << 42) ? 42 :	\
+		(n) & (1ULL << 41) ? 41 :	\
+		(n) & (1ULL << 40) ? 40 :	\
+		(n) & (1ULL << 39) ? 39 :	\
+		(n) & (1ULL << 38) ? 38 :	\
+		(n) & (1ULL << 37) ? 37 :	\
+		(n) & (1ULL << 36) ? 36 :	\
+		(n) & (1ULL << 35) ? 35 :	\
+		(n) & (1ULL << 34) ? 34 :	\
+		(n) & (1ULL << 33) ? 33 :	\
+		(n) & (1ULL << 32) ? 32 :	\
+		(n) & (1ULL << 31) ? 31 :	\
+		(n) & (1ULL << 30) ? 30 :	\
+		(n) & (1ULL << 29) ? 29 :	\
+		(n) & (1ULL << 28) ? 28 :	\
+		(n) & (1ULL << 27) ? 27 :	\
+		(n) & (1ULL << 26) ? 26 :	\
+		(n) & (1ULL << 25) ? 25 :	\
+		(n) & (1ULL << 24) ? 24 :	\
+		(n) & (1ULL << 23) ? 23 :	\
+		(n) & (1ULL << 22) ? 22 :	\
+		(n) & (1ULL << 21) ? 21 :	\
+		(n) & (1ULL << 20) ? 20 :	\
+		(n) & (1ULL << 19) ? 19 :	\
+		(n) & (1ULL << 18) ? 18 :	\
+		(n) & (1ULL << 17) ? 17 :	\
+		(n) & (1ULL << 16) ? 16 :	\
+		(n) & (1ULL << 15) ? 15 :	\
+		(n) & (1ULL << 14) ? 14 :	\
+		(n) & (1ULL << 13) ? 13 :	\
+		(n) & (1ULL << 12) ? 12 :	\
+		(n) & (1ULL << 11) ? 11 :	\
+		(n) & (1ULL << 10) ? 10 :	\
+		(n) & (1ULL <<  9) ?  9 :	\
+		(n) & (1ULL <<  8) ?  8 :	\
+		(n) & (1ULL <<  7) ?  7 :	\
+		(n) & (1ULL <<  6) ?  6 :	\
+		(n) & (1ULL <<  5) ?  5 :	\
+		(n) & (1ULL <<  4) ?  4 :	\
+		(n) & (1ULL <<  3) ?  3 :	\
+		(n) & (1ULL <<  2) ?  2 :	\
+		(n) & (1ULL <<  1) ?  1 :	\
+		(n) & (1ULL <<  0) ?  0 :	\
+		____ilog2_NaN()			\
+				   ) :		\
+	(sizeof(n) <= 4) ?			\
+	__ilog2_u32(n) :			\
+	__ilog2_u64(n)				\
+ )
+
+/**
+ * roundup_pow_of_two - round the given value up to nearest power of two
+ * @n - parameter
+ *
+ * round the given value up to the nearest power of two
+ * - the result is undefined when n == 0
+ * - this can be used to initialise global variables from constant data
+ */
+#define roundup_pow_of_two(n)			\
+(						\
+	__builtin_constant_p(n) ? (		\
+		(n == 1) ? 1 :			\
+		(1UL << (ilog2((n) - 1) + 1))	\
+				   ) :		\
+	__roundup_pow_of_two(n)			\
+ )
+
+/**
+ * rounddown_pow_of_two - round the given value down to nearest power of two
+ * @n - parameter
+ *
+ * round the given value down to the nearest power of two
+ * - the result is undefined when n == 0
+ * - this can be used to initialise global variables from constant data
+ */
+#define rounddown_pow_of_two(n)			\
+(						\
+	__builtin_constant_p(n) ? (		\
+		(1UL << ilog2(n))) :		\
+	__rounddown_pow_of_two(n)		\
+ )
+
+#endif /* _TOOLS_LINUX_LOG2_H */