Merge tag 'perf-tools-2020-12-19' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull perf tools updates from Arnaldo Carvalho de Melo:
 "perf record:
   - Fix memory leak when using '--user-regs=?' to list registers

  aarch64 support:
   - Add aarch64 registers to 'perf record's' --user-regs command line
     option

  aarch64 hw tracing support:
   - Decode memory tagging properties
   - Improve ARM's auxtrace support
   - Add support for ARMv8.3-SPE

  perf kvm:
   - Add kvm-stat for arm64

  perf stat:
   - Add --quiet option

  Cleanups:
   - Fixup function names wrt what is in libperf and what is in
     tools/perf

  Build:
   - Allow building without libbpf in older systems

  New kernel features:
   - Initial support for data/code page size sample type, more to come

  perf annotate:
   - Support MIPS instruction extended support

  perf stack unwinding:
   - Fix separate debug info files when using elfutils' libdw's unwinder

  perf vendor events:
   - Update Intel's Skylake client events to v50
   - Add JSON metrics for ARM's imx8mm DDR Perf
   - Support printing metric groups for system PMUs

  perf build id:
   - Prep work for supporting having the build id provided by the kernel
     in PERF_RECORD_MMAP2 metadata events

  perf stat:
   - Support regex pattern in --for-each-cgroup

  pipe mode:
   - Allow to use stdio functions for pipe mode
   - Support 'perf report's' --header-only for pipe mode
   - Support pipe mode display in 'perf evlist'

  Documentation:
   - Update information about CAP_PERFMON"

* tag 'perf-tools-2020-12-19' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (134 commits)
  perf mem: Factor out a function to generate sort order
  perf sort: Add sort option for data page size
  perf script: Support data page size
  tools headers UAPI: Update asm-generic/unistd.h
  tools headers cpufeatures: Sync with the kernel sources
  tools headers UAPI: Sync linux/prctl.h with the kernel sources
  tools headers UAPI: Sync linux/fscrypt.h with the kernel sources
  tools headers UAPI: Sync linux/const.h with the kernel headers
  tools arch x86: Sync the msr-index.h copy with the kernel sources
  perf trace beauty: Update copy of linux/socket.h with the kernel sources
  tools headers: Update linux/ctype.h with the kernel sources
  tools headers: Add conditional __has_builtin()
  tools headers: Get tools's linux/compiler.h closer to the kernel's
  tools headers UAPI: Sync linux/stat.h with the kernel sources
  tools headers: Syncronize linux/build_bug.h with the kernel sources
  perf tools: Reformat record's control fd man text
  perf config: Fix example command in manpage to conform to syntax specified in the SYNOPSIS section.
  perf test: Make sample-parsing test aware of PERF_SAMPLE_{CODE,DATA}_PAGE_SIZE
  perf tools: Add support to read build id from compressed elf
  perf debug: Add debug_set_file function
  ...

1 files changed, 58 insertions, 0 deletions

diff --git a/tools/lib/string.c b/tools/lib/string.c
index f645343815de..8b6892f959ab 100644
--- a/tools/lib/string.c
+++ b/tools/lib/string.c
@@ -168,3 +168,61 @@ char *strreplace(char *s, char old, char new)
 			*s = new;
 	return s;
 }
+
+static void *check_bytes8(const u8 *start, u8 value, unsigned int bytes)
+{
+	while (bytes) {
+		if (*start != value)
+			return (void *)start;
+		start++;
+		bytes--;
+	}
+	return NULL;
+}
+
+/**
+ * memchr_inv - Find an unmatching character in an area of memory.
+ * @start: The memory area
+ * @c: Find a character other than c
+ * @bytes: The size of the area.
+ *
+ * returns the address of the first character other than @c, or %NULL
+ * if the whole buffer contains just @c.
+ */
+void *memchr_inv(const void *start, int c, size_t bytes)
+{
+	u8 value = c;
+	u64 value64;
+	unsigned int words, prefix;
+
+	if (bytes <= 16)
+		return check_bytes8(start, value, bytes);
+
+	value64 = value;
+	value64 |= value64 << 8;
+	value64 |= value64 << 16;
+	value64 |= value64 << 32;
+
+	prefix = (unsigned long)start % 8;
+	if (prefix) {
+		u8 *r;
+
+		prefix = 8 - prefix;
+		r = check_bytes8(start, value, prefix);
+		if (r)
+			return r;
+		start += prefix;
+		bytes -= prefix;
+	}
+
+	words = bytes / 8;
+
+	while (words) {
+		if (*(u64 *)start != value64)
+			return check_bytes8(start, value, 8);
+		start += 8;
+		words--;
+	}
+
+	return check_bytes8(start, value, bytes % 8);
+}