Merge branch 'perf-tools-for-linus' of git://github.com/acmel/linux

* 'perf-tools-for-linus' of git://github.com/acmel/linux:
  perf tools: Add support for disabling -Werror via WERROR=0
  perf top: Fix userspace sample addr map offset
  perf symbols: Fix issue with binaries using 16-bytes buildids (v2)
  perf tool: Fix endianness handling of u32 data in samples
  perf sort: Fix symbol sort output by separating unresolved samples by type
  perf symbols: Synthesize anonymous mmap events
  perf record: Create events initially disabled and enable after init
  perf symbols: Add some heuristics for choosing the best duplicate symbol
  perf symbols: Preserve symbol scope when parsing /proc/kallsyms
  perf symbols: /proc/kallsyms does not sort module symbols
  perf symbols: Fix ppc64 SEGV in dso__load_sym with debuginfo files
  perf probe: Fix regression of variable finder

13 files changed, 209 insertions, 57 deletions

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 3b8f7b80376b..e9d5c271db69 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -30,6 +30,8 @@ endif
 # Define EXTRA_CFLAGS=-m64 or EXTRA_CFLAGS=-m32 as appropriate for cross-builds.
 #
 # Define NO_DWARF if you do not want debug-info analysis feature at all.
+#
+# Define WERROR=0 to disable treating any warnings as errors.
 
 $(OUTPUT)PERF-VERSION-FILE: .FORCE-PERF-VERSION-FILE
         @$(SHELL_PATH) util/PERF-VERSION-GEN $(OUTPUT)
@@ -63,6 +65,11 @@ ifeq ($(ARCH),x86_64)
         endif
 endif
 
+# Treat warnings as errors unless directed not to
+ifneq ($(WERROR),0)
+        CFLAGS_WERROR := -Werror
+endif
+
 #
 # Include saner warnings here, which can catch bugs:
 #
@@ -95,7 +102,7 @@ ifndef PERF_DEBUG
   CFLAGS_OPTIMIZE = -O6
 endif
 
-CFLAGS = -fno-omit-frame-pointer -ggdb3 -Wall -Wextra -std=gnu99 -Werror $(CFLAGS_OPTIMIZE) -D_FORTIFY_SOURCE=2 $(EXTRA_WARNINGS) $(EXTRA_CFLAGS)
+CFLAGS = -fno-omit-frame-pointer -ggdb3 -Wall -Wextra -std=gnu99 $(CFLAGS_WERROR) $(CFLAGS_OPTIMIZE) -D_FORTIFY_SOURCE=2 $(EXTRA_WARNINGS) $(EXTRA_CFLAGS)
 EXTLIBS = -lpthread -lrt -lelf -lm
 ALL_CFLAGS = $(CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
 ALL_LDFLAGS = $(LDFLAGS)
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 6b0519f885e4..f4c3fbee4bad 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -161,6 +161,7 @@ static void config_attr(struct perf_evsel *evsel, struct perf_evlist *evlist)
         struct perf_event_attr *attr = &evsel->attr;
         int track = !evsel->idx; /* only the first counter needs these */
 
+        attr->disabled          = 1;
         attr->inherit           = !no_inherit;
         attr->read_format       = PERF_FORMAT_TOTAL_TIME_ENABLED |
                                   PERF_FORMAT_TOTAL_TIME_RUNNING |
@@ -671,6 +672,8 @@ static int __cmd_record(int argc, const char **argv)
                 }
         }
 
+        perf_evlist__enable(evsel_list);
+
         /*
          * Let the child rip
          */
diff --git a/tools/perf/builtin-test.c b/tools/perf/builtin-test.c
index 55f4c76f2821..efe696f936e2 100644
--- a/tools/perf/builtin-test.c
+++ b/tools/perf/builtin-test.c
@@ -561,7 +561,7 @@ static int test__basic_mmap(void)
                 }
 
                 err = perf_event__parse_sample(event, attr.sample_type, sample_size,
-                                               false, &sample);
+                                               false, &sample, false);
                 if (err) {
                         pr_err("Can't parse sample, err = %d\n", err);
                         goto out_munmap;
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index a43433f08300..d28013b7d61c 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -191,7 +191,8 @@ static void __zero_source_counters(struct sym_entry *syme)
         symbol__annotate_zero_histograms(sym);
 }
 
-static void record_precise_ip(struct sym_entry *syme, int counter, u64 ip)
+static void record_precise_ip(struct sym_entry *syme, struct map *map,
+                              int counter, u64 ip)
 {
         struct annotation *notes;
         struct symbol *sym;
@@ -205,8 +206,8 @@ static void record_precise_ip(struct sym_entry *syme, int counter, u64 ip)
         if (pthread_mutex_trylock(&notes->lock))
                 return;
 
-        ip = syme->map->map_ip(syme->map, ip);
-        symbol__inc_addr_samples(sym, syme->map, counter, ip);
+        ip = map->map_ip(map, ip);
+        symbol__inc_addr_samples(sym, map, counter, ip);
 
         pthread_mutex_unlock(&notes->lock);
 }
@@ -810,7 +811,7 @@ static void perf_event__process_sample(const union perf_event *event,
                 evsel = perf_evlist__id2evsel(top.evlist, sample->id);
                 assert(evsel != NULL);
                 syme->count[evsel->idx]++;
-                record_precise_ip(syme, evsel->idx, ip);
+                record_precise_ip(syme, al.map, evsel->idx, ip);
                 pthread_mutex_lock(&top.active_symbols_lock);
                 if (list_empty(&syme->node) || !syme->node.next) {
                         static bool first = true;
diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index 3c1b8a632101..437f8ca679a0 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -169,12 +169,17 @@ static int perf_event__synthesize_mmap_events(union perf_event *event,
                         continue;
                 pbf += n + 3;
                 if (*pbf == 'x') { /* vm_exec */
+                        char anonstr[] = "//anon\n";
                         char *execname = strchr(bf, '/');
 
                         /* Catch VDSO */
                         if (execname == NULL)
                                 execname = strstr(bf, "[vdso]");
 
+                        /* Catch anonymous mmaps */
+                        if ((execname == NULL) && !strstr(bf, "["))
+                                execname = anonstr;
+
                         if (execname == NULL)
                                 continue;
 
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index 1d7f66488a88..357a85b85248 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -186,6 +186,6 @@ const char *perf_event__name(unsigned int id);
 
 int perf_event__parse_sample(const union perf_event *event, u64 type,
                              int sample_size, bool sample_id_all,
-                             struct perf_sample *sample);
+                             struct perf_sample *sample, bool swapped);
 
 #endif /* __PERF_RECORD_H */
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index c12bd476c6f7..72e9f4886b6d 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -113,6 +113,19 @@ void perf_evlist__disable(struct perf_evlist *evlist)
         }
 }
 
+void perf_evlist__enable(struct perf_evlist *evlist)
+{
+        int cpu, thread;
+        struct perf_evsel *pos;
+
+        for (cpu = 0; cpu < evlist->cpus->nr; cpu++) {
+                list_for_each_entry(pos, &evlist->entries, node) {
+                        for (thread = 0; thread < evlist->threads->nr; thread++)
+                                ioctl(FD(pos, cpu, thread), PERF_EVENT_IOC_ENABLE);
+                }
+        }
+}
+
 int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
 {
         int nfds = evlist->cpus->nr * evlist->threads->nr * evlist->nr_entries;
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index ce85ae9ae57a..f34915002745 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -54,6 +54,7 @@ int perf_evlist__mmap(struct perf_evlist *evlist, int pages, bool overwrite);
 void perf_evlist__munmap(struct perf_evlist *evlist);
 
 void perf_evlist__disable(struct perf_evlist *evlist);
+void perf_evlist__enable(struct perf_evlist *evlist);
 
 static inline void perf_evlist__set_maps(struct perf_evlist *evlist,
                                          struct cpu_map *cpus,
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index a03a36b7908a..c5748c52318f 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -7,6 +7,8 @@
  * Released under the GPL v2. (and only v2, not any later version)
  */
 
+#include <byteswap.h>
+#include "asm/bug.h"
 #include "evsel.h"
 #include "evlist.h"
 #include "util.h"
@@ -342,10 +344,20 @@ static bool sample_overlap(const union perf_event *event,
 
 int perf_event__parse_sample(const union perf_event *event, u64 type,
                              int sample_size, bool sample_id_all,
-                             struct perf_sample *data)
+                             struct perf_sample *data, bool swapped)
 {
         const u64 *array;
 
+        /*
+         * used for cross-endian analysis. See git commit 65014ab3
+         * for why this goofiness is needed.
+         */
+        union {
+                u64 val64;
+                u32 val32[2];
+        } u;
+
+
         data->cpu = data->pid = data->tid = -1;
         data->stream_id = data->id = data->time = -1ULL;
 
@@ -366,9 +378,16 @@ int perf_event__parse_sample(const union perf_event *event, u64 type,
         }
 
         if (type & PERF_SAMPLE_TID) {
-                u32 *p = (u32 *)array;
-                data->pid = p[0];
-                data->tid = p[1];
+                u.val64 = *array;
+                if (swapped) {
+                        /* undo swap of u64, then swap on individual u32s */
+                        u.val64 = bswap_64(u.val64);
+                        u.val32[0] = bswap_32(u.val32[0]);
+                        u.val32[1] = bswap_32(u.val32[1]);
+                }
+
+                data->pid = u.val32[0];
+                data->tid = u.val32[1];
                 array++;
         }
 
@@ -395,8 +414,15 @@ int perf_event__parse_sample(const union perf_event *event, u64 type,
         }
 
         if (type & PERF_SAMPLE_CPU) {
-                u32 *p = (u32 *)array;
-                data->cpu = *p;
+
+                u.val64 = *array;
+                if (swapped) {
+                        /* undo swap of u64, then swap on individual u32s */
+                        u.val64 = bswap_64(u.val64);
+                        u.val32[0] = bswap_32(u.val32[0]);
+                }
+
+                data->cpu = u.val32[0];
                 array++;
         }
 
@@ -423,18 +449,24 @@ int perf_event__parse_sample(const union perf_event *event, u64 type,
         }
 
         if (type & PERF_SAMPLE_RAW) {
-                u32 *p = (u32 *)array;
+                u.val64 = *array;
+                if (WARN_ONCE(swapped,
+                              "Endianness of raw data not corrected!\n")) {
+                        /* undo swap of u64, then swap on individual u32s */
+                        u.val64 = bswap_64(u.val64);
+                        u.val32[0] = bswap_32(u.val32[0]);
+                        u.val32[1] = bswap_32(u.val32[1]);
+                }
 
                 if (sample_overlap(event, array, sizeof(u32)))
                         return -EFAULT;
 
-                data->raw_size = *p;
-                p++;
+                data->raw_size = u.val32[0];
 
-                if (sample_overlap(event, p, data->raw_size))
+                if (sample_overlap(event, &u.val32[1], data->raw_size))
                         return -EFAULT;
 
-                data->raw_data = p;
+                data->raw_data = &u.val32[1];
         }
 
         return 0;
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 555fc3864b90..5d732621a462 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -659,7 +659,7 @@ static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf)
                 if (!die_find_variable_at(&pf->cu_die, pf->pvar->var, 0, &vr_die))
                         ret = -ENOENT;
         }
-        if (ret == 0)
+        if (ret >= 0)
                 ret = convert_variable(&vr_die, pf);
 
         if (ret < 0)
diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h
index 170601e67d6b..974d0cbee5e9 100644
--- a/tools/perf/util/session.h
+++ b/tools/perf/util/session.h
@@ -162,7 +162,8 @@ static inline int perf_session__parse_sample(struct perf_session *session,
 {
         return perf_event__parse_sample(event, session->sample_type,
                                         session->sample_size,
-                                        session->sample_id_all, sample);
+                                        session->sample_id_all, sample,
+                                        session->header.needs_swap);
 }
 
 struct perf_evsel *perf_session__find_first_evtype(struct perf_session *session,
diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 401e220566fd..1ee8f1e40f18 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -151,11 +151,17 @@ sort__sym_cmp(struct hist_entry *left, struct hist_entry *right)
 {
         u64 ip_l, ip_r;
 
+        if (!left->ms.sym && !right->ms.sym)
+                return right->level - left->level;
+
+        if (!left->ms.sym || !right->ms.sym)
+                return cmp_null(left->ms.sym, right->ms.sym);
+
         if (left->ms.sym == right->ms.sym)
                 return 0;
 
-        ip_l = left->ms.sym ? left->ms.sym->start : left->ip;
-        ip_r = right->ms.sym ? right->ms.sym->start : right->ip;
+        ip_l = left->ms.sym->start;
+        ip_r = right->ms.sym->start;
 
         return (int64_t)(ip_r - ip_l);
 }
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 469c0264ed29..40eeaf07725b 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -74,16 +74,104 @@ static void dso__set_sorted_by_name(struct dso *dso, enum map_type type)
 
 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
 {
+        symbol_type = toupper(symbol_type);
+
         switch (map_type) {
         case MAP__FUNCTION:
                 return symbol_type == 'T' || symbol_type == 'W';
         case MAP__VARIABLE:
-                return symbol_type == 'D' || symbol_type == 'd';
+                return symbol_type == 'D';
         default:
                 return false;
         }
 }
 
+static int prefix_underscores_count(const char *str)
+{
+        const char *tail = str;
+
+        while (*tail == '_')
+                tail++;
+
+        return tail - str;
+}
+
+#define SYMBOL_A 0
+#define SYMBOL_B 1
+
+static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
+{
+        s64 a;
+        s64 b;
+
+        /* Prefer a symbol with non zero length */
+        a = syma->end - syma->start;
+        b = symb->end - symb->start;
+        if ((b == 0) && (a > 0))
+                return SYMBOL_A;
+        else if ((a == 0) && (b > 0))
+                return SYMBOL_B;
+
+        /* Prefer a non weak symbol over a weak one */
+        a = syma->binding == STB_WEAK;
+        b = symb->binding == STB_WEAK;
+        if (b && !a)
+                return SYMBOL_A;
+        if (a && !b)
+                return SYMBOL_B;
+
+        /* Prefer a global symbol over a non global one */
+        a = syma->binding == STB_GLOBAL;
+        b = symb->binding == STB_GLOBAL;
+        if (a && !b)
+                return SYMBOL_A;
+        if (b && !a)
+                return SYMBOL_B;
+
+        /* Prefer a symbol with less underscores */
+        a = prefix_underscores_count(syma->name);
+        b = prefix_underscores_count(symb->name);
+        if (b > a)
+                return SYMBOL_A;
+        else if (a > b)
+                return SYMBOL_B;
+
+        /* If all else fails, choose the symbol with the longest name */
+        if (strlen(syma->name) >= strlen(symb->name))
+                return SYMBOL_A;
+        else
+                return SYMBOL_B;
+}
+
+static void symbols__fixup_duplicate(struct rb_root *symbols)
+{
+        struct rb_node *nd;
+        struct symbol *curr, *next;
+
+        nd = rb_first(symbols);
+
+        while (nd) {
+                curr = rb_entry(nd, struct symbol, rb_node);
+again:
+                nd = rb_next(&curr->rb_node);
+                next = rb_entry(nd, struct symbol, rb_node);
+
+                if (!nd)
+                        break;
+
+                if (curr->start != next->start)
+                        continue;
+
+                if (choose_best_symbol(curr, next) == SYMBOL_A) {
+                        rb_erase(&next->rb_node, symbols);
+                        goto again;
+                } else {
+                        nd = rb_next(&curr->rb_node);
+                        rb_erase(&curr->rb_node, symbols);
+                }
+        }
+}
+
 static void symbols__fixup_end(struct rb_root *symbols)
 {
         struct rb_node *nd, *prevnd = rb_first(symbols);
@@ -438,18 +526,11 @@ int kallsyms__parse(const char *filename, void *arg,
         char *line = NULL;
         size_t n;
         int err = -1;
-        u64 prev_start = 0;
-        char prev_symbol_type = 0;
-        char *prev_symbol_name;
         FILE *file = fopen(filename, "r");
 
         if (file == NULL)
                 goto out_failure;
 
-        prev_symbol_name = malloc(KSYM_NAME_LEN);
-        if (prev_symbol_name == NULL)
-                goto out_close;
-
         err = 0;
 
         while (!feof(file)) {
@@ -470,7 +551,7 @@ int kallsyms__parse(const char *filename, void *arg,
                 if (len + 2 >= line_len)
                         continue;
 
-                symbol_type = toupper(line[len]);
+                symbol_type = line[len];
                 len += 2;
                 symbol_name = line + len;
                 len = line_len - len;
@@ -480,24 +561,18 @@ int kallsyms__parse(const char *filename, void *arg,
                         break;
                 }
 
-                if (prev_symbol_type) {
-                        u64 end = start;
-                        if (end != prev_start)
-                                --end;
-                        err = process_symbol(arg, prev_symbol_name,
-                                             prev_symbol_type, prev_start, end);
-                        if (err)
-                                break;
-                }
-
-                memcpy(prev_symbol_name, symbol_name, len + 1);
-                prev_symbol_type = symbol_type;
-                prev_start = start;
+                /*
+                 * module symbols are not sorted so we add all
+                 * symbols with zero length and rely on
+                 * symbols__fixup_end() to fix it up.
+                 */
+                err = process_symbol(arg, symbol_name,
+                                     symbol_type, start, start);
+                if (err)
+                        break;
         }
 
-        free(prev_symbol_name);
         free(line);
-out_close:
         fclose(file);
         return err;
 
@@ -703,6 +778,9 @@ int dso__load_kallsyms(struct dso *dso, const char *filename,
         if (dso__load_all_kallsyms(dso, filename, map) < 0)
                 return -1;
 
+        symbols__fixup_duplicate(&dso->symbols[map->type]);
+        symbols__fixup_end(&dso->symbols[map->type]);
+
         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
                 dso->symtab_type = SYMTAB__GUEST_KALLSYMS;
         else
@@ -1092,8 +1170,7 @@ static int dso__load_sym(struct dso *dso, struct map *map, const char *name,
         if (dso->has_build_id) {
                 u8 build_id[BUILD_ID_SIZE];
 
-                if (elf_read_build_id(elf, build_id,
-                                      BUILD_ID_SIZE) != BUILD_ID_SIZE)
+                if (elf_read_build_id(elf, build_id, BUILD_ID_SIZE) < 0)
                         goto out_elf_end;
 
                 if (!dso__build_id_equal(dso, build_id))
@@ -1111,6 +1188,8 @@ static int dso__load_sym(struct dso *dso, struct map *map, const char *name,
         }
 
         opdsec = elf_section_by_name(elf, &ehdr, &opdshdr, ".opd", &opdidx);
+        if (opdshdr.sh_type != SHT_PROGBITS)
+                opdsec = NULL;
         if (opdsec)
                 opddata = elf_rawdata(opdsec, NULL);
 
@@ -1276,6 +1355,7 @@ new_symbol:
          * For misannotated, zeroed, ASM function sizes.
          */
         if (nr > 0) {
+                symbols__fixup_duplicate(&dso->symbols[map->type]);
                 symbols__fixup_end(&dso->symbols[map->type]);
                 if (kmap) {
                         /*
@@ -1362,8 +1442,8 @@ static int elf_read_build_id(Elf *elf, void *bf, size_t size)
         ptr = data->d_buf;
         while (ptr < (data->d_buf + data->d_size)) {
                 GElf_Nhdr *nhdr = ptr;
-                int namesz = NOTE_ALIGN(nhdr->n_namesz),
-                    descsz = NOTE_ALIGN(nhdr->n_descsz);
+                size_t namesz = NOTE_ALIGN(nhdr->n_namesz),
+                       descsz = NOTE_ALIGN(nhdr->n_descsz);
                 const char *name;
 
                 ptr += sizeof(*nhdr);
@@ -1372,8 +1452,10 @@ static int elf_read_build_id(Elf *elf, void *bf, size_t size)
                 if (nhdr->n_type == NT_GNU_BUILD_ID &&
                     nhdr->n_namesz == sizeof("GNU")) {
                         if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
-                                memcpy(bf, ptr, BUILD_ID_SIZE);
-                                err = BUILD_ID_SIZE;
+                                size_t sz = min(size, descsz);
+                                memcpy(bf, ptr, sz);
+                                memset(bf + sz, 0, size - sz);
+                                err = descsz;
                                 break;
                         }
                 }
@@ -1425,7 +1507,7 @@ int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
         while (1) {
                 char bf[BUFSIZ];
                 GElf_Nhdr nhdr;
-                int namesz, descsz;
+                size_t namesz, descsz;
 
                 if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
                         break;
@@ -1434,15 +1516,16 @@ int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
                 descsz = NOTE_ALIGN(nhdr.n_descsz);
                 if (nhdr.n_type == NT_GNU_BUILD_ID &&
                     nhdr.n_namesz == sizeof("GNU")) {
-                        if (read(fd, bf, namesz) != namesz)
+                        if (read(fd, bf, namesz) != (ssize_t)namesz)
                                 break;
                         if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
-                                if (read(fd, build_id,
-                                    BUILD_ID_SIZE) == BUILD_ID_SIZE) {
+                                size_t sz = min(descsz, size);
+                                if (read(fd, build_id, sz) == (ssize_t)sz) {
+                                        memset(build_id + sz, 0, size - sz);
                                         err = 0;
                                         break;
                                 }
-                        } else if (read(fd, bf, descsz) != descsz)
+                        } else if (read(fd, bf, descsz) != (ssize_t)descsz)
                                 break;
                 } else {
                         int n = namesz + descsz;