Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fixes and cleanups from Ingo Molnar:
 "A kernel fix plus mostly tooling fixes, but also some tooling
  restructuring and cleanups"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
  perf: Fix building warning on ARM 32
  perf symbols: Fix use after free in filename__read_build_id
  perf evlist: Use roundup_pow_of_two
  tools: Adopt roundup_pow_of_two
  perf tools: Make the mmap length autotuning more robust
  tools: Adopt rounddown_pow_of_two and deps
  tools: Adopt fls_long and deps
  tools: Move bitops.h from tools/perf/util to tools/
  tools: Introduce asm-generic/bitops.h
  tools lib: Move asm-generic/bitops/find.h code to tools/include and tools/lib
  tools: Whitespace prep patches for moving bitops.h
  tools: Move code originally from asm-generic/atomic.h into tools/include/asm-generic/
  tools: Move code originally from linux/log2.h to tools/include/linux/
  tools: Move __ffs implementation to tools/include/asm-generic/bitops/__ffs.h
  perf evlist: Do not use hard coded value for a mmap_pages default
  perf trace: Let the perf_evlist__mmap autosize the number of pages to use
  perf evlist: Improve the strerror_mmap method
  perf evlist: Clarify sterror_mmap variable names
  perf evlist: Fixup brown paper bag on "hint" for --mmap-pages cmdline arg
  perf trace: Provide a better explanation when mmap fails
  ...

12 files changed, 114 insertions, 290 deletions

diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index e8d79e5bfaf7..0c72680a977f 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -410,21 +410,18 @@ int perf_session__cache_build_ids(struct perf_session *session)
 {
         struct rb_node *nd;
         int ret;
-        char debugdir[PATH_MAX];
 
         if (no_buildid_cache)
                 return 0;
 
-        snprintf(debugdir, sizeof(debugdir), "%s", buildid_dir);
-
-        if (mkdir(debugdir, 0755) != 0 && errno != EEXIST)
+        if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
                 return -1;
 
-        ret = machine__cache_build_ids(&session->machines.host, debugdir);
+        ret = machine__cache_build_ids(&session->machines.host, buildid_dir);
 
         for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
-                ret |= machine__cache_build_ids(pos, debugdir);
+                ret |= machine__cache_build_ids(pos, buildid_dir);
         }
         return ret ? -1 : 0;
 }
diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index cf524a35cc84..64b377e591e4 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -77,7 +77,7 @@ int parse_callchain_record_opt(const char *arg)
                                 ret = 0;
                         } else
                                 pr_err("callchain: No more arguments "
-                                       "needed for -g fp\n");
+                                       "needed for --call-graph fp\n");
                         break;
 
 #ifdef HAVE_DWARF_UNWIND_SUPPORT
diff --git a/tools/perf/util/config.c b/tools/perf/util/config.c
index 57ff826f150b..e18f653cd7db 100644
--- a/tools/perf/util/config.c
+++ b/tools/perf/util/config.c
@@ -522,7 +522,7 @@ static int buildid_dir_command_config(const char *var, const char *value,
         const char *v;
 
         /* same dir for all commands */
-        if (!prefixcmp(var, "buildid.") && !strcmp(var + 8, "dir")) {
+        if (!strcmp(var, "buildid.dir")) {
                 v = perf_config_dirname(var, value);
                 if (!v)
                         return -1;
@@ -539,12 +539,14 @@ static void check_buildid_dir_config(void)
         perf_config(buildid_dir_command_config, &c);
 }
 
-void set_buildid_dir(void)
+void set_buildid_dir(const char *dir)
 {
-        buildid_dir[0] = '\0';
+        if (dir)
+                scnprintf(buildid_dir, MAXPATHLEN-1, "%s", dir);
 
         /* try config file */
-        check_buildid_dir_config();
+        if (buildid_dir[0] == '\0')
+                check_buildid_dir_config();
 
         /* default to $HOME/.debug */
         if (buildid_dir[0] == '\0') {
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index cfbe2b99b9aa..cbab1fb77b1d 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -8,6 +8,7 @@
  */
 #include "util.h"
 #include <api/fs/debugfs.h>
+#include <api/fs/fs.h>
 #include <poll.h>
 #include "cpumap.h"
 #include "thread_map.h"
@@ -24,6 +25,7 @@
 
 #include <linux/bitops.h>
 #include <linux/hash.h>
+#include <linux/log2.h>
 
 static void perf_evlist__mmap_put(struct perf_evlist *evlist, int idx);
 static void __perf_evlist__munmap(struct perf_evlist *evlist, int idx);
@@ -892,10 +894,24 @@ out_unmap:
 
 static size_t perf_evlist__mmap_size(unsigned long pages)
 {
-        /* 512 kiB: default amount of unprivileged mlocked memory */
-        if (pages == UINT_MAX)
-                pages = (512 * 1024) / page_size;
-        else if (!is_power_of_2(pages))
+        if (pages == UINT_MAX) {
+                int max;
+
+                if (sysctl__read_int("kernel/perf_event_mlock_kb", &max) < 0) {
+                        /*
+                         * Pick a once upon a time good value, i.e. things look
+                         * strange since we can't read a sysctl value, but lets not
+                         * die yet...
+                         */
+                        max = 512;
+                } else {
+                        max -= (page_size / 1024);
+                }
+
+                pages = (max * 1024) / page_size;
+                if (!is_power_of_2(pages))
+                        pages = rounddown_pow_of_two(pages);
+        } else if (!is_power_of_2(pages))
                 return 0;
 
         return (pages + 1) * page_size;
@@ -932,7 +948,7 @@ static long parse_pages_arg(const char *str, unsigned long min,
                 /* leave number of pages at 0 */
         } else if (!is_power_of_2(pages)) {
                 /* round pages up to next power of 2 */
-                pages = next_pow2_l(pages);
+                pages = roundup_pow_of_two(pages);
                 if (!pages)
                         return -EINVAL;
                 pr_info("rounding mmap pages size to %lu bytes (%lu pages)\n",
@@ -1483,6 +1499,37 @@ int perf_evlist__strerror_open(struct perf_evlist *evlist __maybe_unused,
         return 0;
 }
 
+int perf_evlist__strerror_mmap(struct perf_evlist *evlist, int err, char *buf, size_t size)
+{
+        char sbuf[STRERR_BUFSIZE], *emsg = strerror_r(err, sbuf, sizeof(sbuf));
+        int pages_attempted = evlist->mmap_len / 1024, pages_max_per_user, printed = 0;
+
+        switch (err) {
+        case EPERM:
+                sysctl__read_int("kernel/perf_event_mlock_kb", &pages_max_per_user);
+                printed += scnprintf(buf + printed, size - printed,
+                                     "Error:\t%s.\n"
+                                     "Hint:\tCheck /proc/sys/kernel/perf_event_mlock_kb (%d kB) setting.\n"
+                                     "Hint:\tTried using %zd kB.\n",
+                                     emsg, pages_max_per_user, pages_attempted);
+
+                if (pages_attempted >= pages_max_per_user) {
+                        printed += scnprintf(buf + printed, size - printed,
+                                             "Hint:\tTry 'sudo sh -c \"echo %d > /proc/sys/kernel/perf_event_mlock_kb\"', or\n",
+                                             pages_max_per_user + pages_attempted);
+                }
+
+                printed += scnprintf(buf + printed, size - printed,
+                                     "Hint:\tTry using a smaller -m/--mmap-pages value.");
+                break;
+        default:
+                scnprintf(buf, size, "%s", emsg);
+                break;
+        }
+
+        return 0;
+}
+
 void perf_evlist__to_front(struct perf_evlist *evlist,
                            struct perf_evsel *move_evsel)
 {
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 649b0c597283..0ba93f67ab94 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -185,6 +185,7 @@ size_t perf_evlist__fprintf(struct perf_evlist *evlist, FILE *fp);
 
 int perf_evlist__strerror_tp(struct perf_evlist *evlist, int err, char *buf, size_t size);
 int perf_evlist__strerror_open(struct perf_evlist *evlist, int err, char *buf, size_t size);
+int perf_evlist__strerror_mmap(struct perf_evlist *evlist, int err, char *buf, size_t size);
 
 static inline unsigned int perf_mmap__read_head(struct perf_mmap *mm)
 {
diff --git a/tools/perf/util/include/linux/bitops.h b/tools/perf/util/include/linux/bitops.h
deleted file mode 100644
index c3294163de17..000000000000
--- a/tools/perf/util/include/linux/bitops.h
+++ /dev/null
@@ -1,162 +0,0 @@
-#ifndef _PERF_LINUX_BITOPS_H_
-#define _PERF_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 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)
-#define BIT_WORD(nr)            ((nr) / BITS_PER_LONG)
-#define BIT_MASK(nr)            (1UL << ((nr) % BITS_PER_LONG))
-
-#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 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;
-}
-
-static inline unsigned long hweight_long(unsigned long w)
-{
-        return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
-}
-
-#define BITOP_WORD(nr)          ((nr) / BITS_PER_LONG)
-
-/**
- * __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;
-}
-
-typedef const unsigned long __attribute__((__may_alias__)) long_alias_t;
-
-/*
- * Find the first set bit in a memory region.
- */
-static inline unsigned long
-find_first_bit(const unsigned long *addr, unsigned long size)
-{
-        long_alias_t *p = (long_alias_t *) addr;
-        unsigned long result = 0;
-        unsigned long tmp;
-
-        while (size & ~(BITS_PER_LONG-1)) {
-                if ((tmp = *(p++)))
-                        goto found;
-                result += BITS_PER_LONG;
-                size -= BITS_PER_LONG;
-        }
-        if (!size)
-                return result;
-
-        tmp = (*p) & (~0UL >> (BITS_PER_LONG - size));
-        if (tmp == 0UL)         /* Are any bits set? */
-                return result + size;   /* Nope. */
-found:
-        return result + __ffs(tmp);
-}
-
-/*
- * Find the next set bit in a memory region.
- */
-static inline unsigned long
-find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset)
-{
-        const unsigned long *p = addr + BITOP_WORD(offset);
-        unsigned long result = offset & ~(BITS_PER_LONG-1);
-        unsigned long tmp;
-
-        if (offset >= size)
-                return size;
-        size -= result;
-        offset %= BITS_PER_LONG;
-        if (offset) {
-                tmp = *(p++);
-                tmp &= (~0UL << offset);
-                if (size < BITS_PER_LONG)
-                        goto found_first;
-                if (tmp)
-                        goto found_middle;
-                size -= BITS_PER_LONG;
-                result += BITS_PER_LONG;
-        }
-        while (size & ~(BITS_PER_LONG-1)) {
-                if ((tmp = *(p++)))
-                        goto found_middle;
-                result += BITS_PER_LONG;
-                size -= BITS_PER_LONG;
-        }
-        if (!size)
-                return result;
-        tmp = *p;
-
-found_first:
-        tmp &= (~0UL >> (BITS_PER_LONG - size));
-        if (tmp == 0UL)         /* Are any bits set? */
-                return result + size;   /* Nope. */
-found_middle:
-        return result + __ffs(tmp);
-}
-
-#endif
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 15dd0a9691ce..94de3e48b490 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1385,19 +1385,46 @@ struct mem_info *sample__resolve_mem(struct perf_sample *sample,
 static int add_callchain_ip(struct thread *thread,
                             struct symbol **parent,
                             struct addr_location *root_al,
-                            int cpumode,
+                            bool branch_history,
                             u64 ip)
 {
         struct addr_location al;
 
         al.filtered = 0;
         al.sym = NULL;
-        if (cpumode == -1)
+        if (branch_history)
                 thread__find_cpumode_addr_location(thread, MAP__FUNCTION,
                                                    ip, &al);
-        else
+        else {
+                u8 cpumode = PERF_RECORD_MISC_USER;
+
+                if (ip >= PERF_CONTEXT_MAX) {
+                        switch (ip) {
+                        case PERF_CONTEXT_HV:
+                                cpumode = PERF_RECORD_MISC_HYPERVISOR;
+                                break;
+                        case PERF_CONTEXT_KERNEL:
+                                cpumode = PERF_RECORD_MISC_KERNEL;
+                                break;
+                        case PERF_CONTEXT_USER:
+                                cpumode = PERF_RECORD_MISC_USER;
+                                break;
+                        default:
+                                pr_debug("invalid callchain context: "
+                                         "%"PRId64"\n", (s64) ip);
+                                /*
+                                 * It seems the callchain is corrupted.
+                                 * Discard all.
+                                 */
+                                callchain_cursor_reset(&callchain_cursor);
+                                return 1;
+                        }
+                        return 0;
+                }
                 thread__find_addr_location(thread, cpumode, MAP__FUNCTION,
                                    ip, &al);
+        }
+
         if (al.sym != NULL) {
                 if (sort__has_parent && !*parent &&
                     symbol__match_regex(al.sym, &parent_regex))
@@ -1480,11 +1507,8 @@ static int thread__resolve_callchain_sample(struct thread *thread,
                                              struct addr_location *root_al,
                                              int max_stack)
 {
-        u8 cpumode = PERF_RECORD_MISC_USER;
         int chain_nr = min(max_stack, (int)chain->nr);
-        int i;
-        int j;
-        int err;
+        int i, j, err;
         int skip_idx = -1;
         int first_call = 0;
 
@@ -1542,10 +1566,10 @@ static int thread__resolve_callchain_sample(struct thread *thread,
 
                 for (i = 0; i < nr; i++) {
                         err = add_callchain_ip(thread, parent, root_al,
-                                               -1, be[i].to);
+                                               true, be[i].to);
                         if (!err)
                                 err = add_callchain_ip(thread, parent, root_al,
-                                                       -1, be[i].from);
+                                                       true, be[i].from);
                         if (err == -EINVAL)
                                 break;
                         if (err)
@@ -1574,36 +1598,10 @@ check_calls:
 #endif
                 ip = chain->ips[j];
 
-                if (ip >= PERF_CONTEXT_MAX) {
-                        switch (ip) {
-                        case PERF_CONTEXT_HV:
-                                cpumode = PERF_RECORD_MISC_HYPERVISOR;
-                                break;
-                        case PERF_CONTEXT_KERNEL:
-                                cpumode = PERF_RECORD_MISC_KERNEL;
-                                break;
-                        case PERF_CONTEXT_USER:
-                                cpumode = PERF_RECORD_MISC_USER;
-                                break;
-                        default:
-                                pr_debug("invalid callchain context: "
-                                         "%"PRId64"\n", (s64) ip);
-                                /*
-                                 * It seems the callchain is corrupted.
-                                 * Discard all.
-                                 */
-                                callchain_cursor_reset(&callchain_cursor);
-                                return 0;
-                        }
-                        continue;
-                }
+                err = add_callchain_ip(thread, parent, root_al, false, ip);
 
-                err = add_callchain_ip(thread, parent, root_al,
-                                       cpumode, ip);
-                if (err == -EINVAL)
-                        break;
                 if (err)
-                        return err;
+                        return (err < 0) ? err : 0;
         }
 
         return 0;
diff --git a/tools/perf/util/record.c b/tools/perf/util/record.c
index cf69325b985f..8acd0df88b5c 100644
--- a/tools/perf/util/record.c
+++ b/tools/perf/util/record.c
@@ -137,16 +137,7 @@ void perf_evlist__config(struct perf_evlist *evlist, struct record_opts *opts)
 
 static int get_max_rate(unsigned int *rate)
 {
-        char path[PATH_MAX];
-        const char *procfs = procfs__mountpoint();
-
-        if (!procfs)
-                return -1;
-
-        snprintf(path, PATH_MAX,
-                 "%s/sys/kernel/perf_event_max_sample_rate", procfs);
-
-        return filename__read_int(path, (int *) rate);
+        return sysctl__read_int("kernel/perf_event_max_sample_rate", (int *)rate);
 }
 
 static int record_opts__config_freq(struct record_opts *opts)
diff --git a/tools/perf/util/srcline.c b/tools/perf/util/srcline.c
index e73b6a5c9e0f..c93fb0c5bd0b 100644
--- a/tools/perf/util/srcline.c
+++ b/tools/perf/util/srcline.c
@@ -20,7 +20,7 @@
 
 struct a2l_data {
         const char      *input;
-        unsigned long   addr;
+        u64             addr;
 
         bool            found;
         const char      *filename;
@@ -147,7 +147,7 @@ static void addr2line_cleanup(struct a2l_data *a2l)
         free(a2l);
 }
 
-static int addr2line(const char *dso_name, unsigned long addr,
+static int addr2line(const char *dso_name, u64 addr,
                      char **file, unsigned int *line, struct dso *dso)
 {
         int ret = 0;
@@ -193,7 +193,7 @@ void dso__free_a2l(struct dso *dso)
 
 #else /* HAVE_LIBBFD_SUPPORT */
 
-static int addr2line(const char *dso_name, unsigned long addr,
+static int addr2line(const char *dso_name, u64 addr,
                      char **file, unsigned int *line_nr,
                      struct dso *dso __maybe_unused)
 {
@@ -252,7 +252,7 @@ void dso__free_a2l(struct dso *dso __maybe_unused)
  */
 #define A2L_FAIL_LIMIT 123
 
-char *get_srcline(struct dso *dso, unsigned long addr, struct symbol *sym,
+char *get_srcline(struct dso *dso, u64 addr, struct symbol *sym,
                   bool show_sym)
 {
         char *file = NULL;
@@ -293,10 +293,10 @@ out:
                 dso__free_a2l(dso);
         }
         if (sym) {
-                if (asprintf(&srcline, "%s+%ld", show_sym ? sym->name : "",
+                if (asprintf(&srcline, "%s+%" PRIu64, show_sym ? sym->name : "",
                                         addr - sym->start) < 0)
                         return SRCLINE_UNKNOWN;
-        } else if (asprintf(&srcline, "%s[%lx]", dso->short_name, addr) < 0)
+        } else if (asprintf(&srcline, "%s[%" PRIx64 "]", dso->short_name, addr) < 0)
                 return SRCLINE_UNKNOWN;
         return srcline;
 }
diff --git a/tools/perf/util/symbol-minimal.c b/tools/perf/util/symbol-minimal.c
index fa585c63f56a..d7efb03b3f9a 100644
--- a/tools/perf/util/symbol-minimal.c
+++ b/tools/perf/util/symbol-minimal.c
@@ -129,6 +129,7 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
 
                 for (i = 0, phdr = buf; i < ehdr.e_phnum; i++, phdr++) {
                         void *tmp;
+                        long offset;
 
                         if (need_swap) {
                                 phdr->p_type = bswap_32(phdr->p_type);
@@ -140,12 +141,13 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
                                 continue;
 
                         buf_size = phdr->p_filesz;
+                        offset = phdr->p_offset;
                         tmp = realloc(buf, buf_size);
                         if (tmp == NULL)
                                 goto out_free;
 
                         buf = tmp;
-                        fseek(fp, phdr->p_offset, SEEK_SET);
+                        fseek(fp, offset, SEEK_SET);
                         if (fread(buf, buf_size, 1, fp) != 1)
                                 goto out_free;
 
@@ -178,6 +180,7 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
 
                 for (i = 0, phdr = buf; i < ehdr.e_phnum; i++, phdr++) {
                         void *tmp;
+                        long offset;
 
                         if (need_swap) {
                                 phdr->p_type = bswap_32(phdr->p_type);
@@ -189,12 +192,13 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
                                 continue;
 
                         buf_size = phdr->p_filesz;
+                        offset = phdr->p_offset;
                         tmp = realloc(buf, buf_size);
                         if (tmp == NULL)
                                 goto out_free;
 
                         buf = tmp;
-                        fseek(fp, phdr->p_offset, SEEK_SET);
+                        fseek(fp, offset, SEEK_SET);
                         if (fread(buf, buf_size, 1, fp) != 1)
                                 goto out_free;
 
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index d5eab3f3323f..b86744f29eef 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -442,23 +442,6 @@ unsigned long parse_tag_value(const char *str, struct parse_tag *tags)
         return (unsigned long) -1;
 }
 
-int filename__read_int(const char *filename, int *value)
-{
-        char line[64];
-        int fd = open(filename, O_RDONLY), err = -1;
-
-        if (fd < 0)
-                return -1;
-
-        if (read(fd, line, sizeof(line)) > 0) {
-                *value = atoi(line);
-                err = 0;
-        }
-
-        close(fd);
-        return err;
-}
-
 int filename__read_str(const char *filename, char **buf, size_t *sizep)
 {
         size_t size = 0, alloc_size = 0;
@@ -523,16 +506,9 @@ const char *get_filename_for_perf_kvm(void)
 
 int perf_event_paranoid(void)
 {
-        char path[PATH_MAX];
-        const char *procfs = procfs__mountpoint();
         int value;
 
-        if (!procfs)
-                return INT_MAX;
-
-        scnprintf(path, PATH_MAX, "%s/sys/kernel/perf_event_paranoid", procfs);
-
-        if (filename__read_int(path, &value))
+        if (sysctl__read_int("kernel/perf_event_paranoid", &value))
                 return INT_MAX;
 
         return value;
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 419bee030f83..027a5153495c 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -153,7 +153,7 @@ extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)))
 extern void set_die_routine(void (*routine)(const char *err, va_list params) NORETURN);
 
 extern int prefixcmp(const char *str, const char *prefix);
-extern void set_buildid_dir(void);
+extern void set_buildid_dir(const char *dir);
 
 static inline const char *skip_prefix(const char *str, const char *prefix)
 {
@@ -269,35 +269,6 @@ void event_attr_init(struct perf_event_attr *attr);
 #define _STR(x) #x
 #define STR(x) _STR(x)
 
-/*
- *  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));
-}
-
-static inline unsigned next_pow2(unsigned x)
-{
-        if (!x)
-                return 1;
-        return 1ULL << (32 - __builtin_clz(x - 1));
-}
-
-static inline unsigned long next_pow2_l(unsigned long x)
-{
-#if BITS_PER_LONG == 64
-        if (x <= (1UL << 31))
-                return next_pow2(x);
-        return (unsigned long)next_pow2(x >> 32) << 32;
-#else
-        return next_pow2(x);
-#endif
-}
-
 size_t hex_width(u64 v);
 int hex2u64(const char *ptr, u64 *val);
 
@@ -339,11 +310,10 @@ static inline int path__join3(char *bf, size_t size,
 struct dso;
 struct symbol;
 
-char *get_srcline(struct dso *dso, unsigned long addr, struct symbol *sym,
+char *get_srcline(struct dso *dso, u64 addr, struct symbol *sym,
                   bool show_sym);
 void free_srcline(char *srcline);
 
-int filename__read_int(const char *filename, int *value);
 int filename__read_str(const char *filename, char **buf, size_t *sizep);
 int perf_event_paranoid(void);