perf_counter tools: Add 'perf annotate' feature

Add new perf sub-command to display annotated source code:

 $ perf annotate decode_tree_entry

------------------------------------------------
 Percent |	Source code & Disassembly of /home/mingo/git/git
------------------------------------------------
         :
         :	/home/mingo/git/git:     file format elf64-x86-64
         :
         :
         :	Disassembly of section .text:
         :
         :	00000000004a0da0 <decode_tree_entry>:
         :		*modep = mode;
         :		return str;
         :	}
         :
         :	static void decode_tree_entry(struct tree_desc *desc, const char *buf, unsigned long size)
         :	{
    3.82 :	  4a0da0:	41 54                	push   %r12
         :		const char *path;
         :		unsigned int mode, len;
         :
         :		if (size < 24 || buf[size - 21])
    0.17 :	  4a0da2:	48 83 fa 17          	cmp    $0x17,%rdx
         :		*modep = mode;
         :		return str;
         :	}
         :
         :	static void decode_tree_entry(struct tree_desc *desc, const char *buf, unsigned long size)
         :	{
    0.00 :	  4a0da6:	49 89 fc             	mov    %rdi,%r12
    0.00 :	  4a0da9:	55                   	push   %rbp
    3.37 :	  4a0daa:	53                   	push   %rbx
         :		const char *path;
         :		unsigned int mode, len;
         :
         :		if (size < 24 || buf[size - 21])
    0.08 :	  4a0dab:	76 73                	jbe    4a0e20 <decode_tree_entry+0x80>
    0.00 :	  4a0dad:	80 7c 16 eb 00       	cmpb   $0x0,-0x15(%rsi,%rdx,1)
    3.48 :	  4a0db2:	75 6c                	jne    4a0e20 <decode_tree_entry+0x80>
         :	static const char *get_mode(const char *str, unsigned int *modep)
         :	{
         :		unsigned char c;
         :		unsigned int mode = 0;
         :
         :		if (*str == ' ')
    1.94 :	  4a0db4:	0f b6 06             	movzbl (%rsi),%eax
    0.39 :	  4a0db7:	3c 20                	cmp    $0x20,%al
    0.00 :	  4a0db9:	74 65                	je     4a0e20 <decode_tree_entry+0x80>
         :			return NULL;
         :
         :		while ((c = *str++) != ' ') {
    0.06 :	  4a0dbb:	89 c2                	mov    %eax,%edx
         :			if (c < '0' || c > '7')
    1.99 :	  4a0dbd:	31 ed                	xor    %ebp,%ebp
         :		unsigned int mode = 0;
         :
         :		if (*str == ' ')
         :			return NULL;
         :
         :		while ((c = *str++) != ' ') {
    1.74 :	  4a0dbf:	48 8d 5e 01          	lea    0x1(%rsi),%rbx
         :			if (c < '0' || c > '7')
    0.00 :	  4a0dc3:	8d 42 d0             	lea    -0x30(%rdx),%eax
    0.17 :	  4a0dc6:	3c 07                	cmp    $0x7,%al
    0.00 :	  4a0dc8:	76 0d                	jbe    4a0dd7 <decode_tree_entry+0x37>
    0.00 :	  4a0dca:	eb 54                	jmp    4a0e20 <decode_tree_entry+0x80>
    0.00 :	  4a0dcc:	0f 1f 40 00          	nopl   0x0(%rax)
   16.57 :	  4a0dd0:	8d 42 d0             	lea    -0x30(%rdx),%eax
    0.14 :	  4a0dd3:	3c 07                	cmp    $0x7,%al
    0.00 :	  4a0dd5:	77 49                	ja     4a0e20 <decode_tree_entry+0x80>
         :				return NULL;
         :			mode = (mode << 3) + (c - '0');
    3.12 :	  4a0dd7:	0f b6 c2             	movzbl %dl,%eax
         :		unsigned int mode = 0;
         :
         :		if (*str == ' ')
         :			return NULL;
         :
         :		while ((c = *str++) != ' ') {
    0.00 :	  4a0dda:	0f b6 13             	movzbl (%rbx),%edx
   16.74 :	  4a0ddd:	48 83 c3 01          	add    $0x1,%rbx
         :			if (c < '0' || c > '7')
         :				return NULL;
         :			mode = (mode << 3) + (c - '0');

The first column is the percentage of samples that arrived on that
particular line - relative to the total cost of the function.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

4 files changed, 229 insertions, 139 deletions

diff --git a/Documentation/perf_counter/Documentation/perf-annotate.txt b/Documentation/perf_counter/Documentation/perf-annotate.txt
index a9d6d5ee2701..c9dcade06831 100644
--- a/Documentation/perf_counter/Documentation/perf-annotate.txt
+++ b/Documentation/perf_counter/Documentation/perf-annotate.txt
@@ -3,7 +3,7 @@ perf-annotate(1)
 
 NAME
 ----
-perf-annotate - Read perf.data (created by perf record) and annotate functions
+perf-annotate - Read perf.data (created by perf record) and display annotated code
 
 SYNOPSIS
 --------
@@ -12,8 +12,11 @@ SYNOPSIS
 
 DESCRIPTION
 -----------
-This command displays the performance counter profile information recorded
-via perf record.
+This command reads the input file and displays an annotated version of the
+code. If the object file has debug symbols then the source code will be
+displayed alongside assembly code.
+
+If there is no debug info in the object, then annotated assembly is displayed.
 
 OPTIONS
 -------
diff --git a/Documentation/perf_counter/builtin-annotate.c b/Documentation/perf_counter/builtin-annotate.c
index d656484ec983..116a3978b44c 100644
--- a/Documentation/perf_counter/builtin-annotate.c
+++ b/Documentation/perf_counter/builtin-annotate.c
@@ -28,7 +28,7 @@
 static char             const *input_name = "perf.data";
 static char             *vmlinux = NULL;
 
-static char             default_sort_order[] = "comm,dso";
+static char             default_sort_order[] = "comm,symbol";
 static char             *sort_order = default_sort_order;
 
 static int              input;
@@ -38,7 +38,6 @@ static int		dump_trace = 0;
 #define dprintf(x...)   do { if (dump_trace) printf(x); } while (0)
 
 static int              verbose;
-static int              full_paths;
 
 static unsigned long    page_size;
 static unsigned long    mmap_window = 32;
@@ -89,6 +88,7 @@ static LIST_HEAD(dsos);
 static struct dso *kernel_dso;
 static struct dso *vdso;
 
+
 static void dsos__add(struct dso *dso)
 {
         list_add_tail(&dso->node, &dsos);
@@ -176,20 +176,6 @@ static int load_kernel(void)
         return err;
 }
 
-static char __cwd[PATH_MAX];
-static char *cwd = __cwd;
-static int cwdlen;
-
-static int strcommon(const char *pathname)
-{
-        int n = 0;
-
-        while (pathname[n] == cwd[n] && n < cwdlen)
-                ++n;
-
-        return n;
-}
-
 struct map {
         struct list_head node;
         uint64_t         start;
@@ -215,17 +201,6 @@ static struct map *map__new(struct mmap_event *event)
 
         if (self != NULL) {
                 const char *filename = event->filename;
-                char newfilename[PATH_MAX];
-
-                if (cwd) {
-                        int n = strcommon(filename);
-
-                        if (n == cwdlen) {
-                                snprintf(newfilename, sizeof(newfilename),
-                                         ".%s", filename + n);
-                                filename = newfilename;
-                        }
-                }
 
                 self->start = event->start;
                 self->end   = event->start + event->len;
@@ -669,44 +644,36 @@ hist_entry__collapse(struct hist_entry *left, struct hist_entry *right)
         return cmp;
 }
 
-static size_t
-hist_entry__fprintf(FILE *fp, struct hist_entry *self, uint64_t total_samples)
+/*
+ * collect histogram counts
+ */
+static void hist_hit(struct hist_entry *he, uint64_t ip)
 {
-        struct sort_entry *se;
-        size_t ret;
+        unsigned int sym_size, offset;
+        struct symbol *sym = he->sym;
 
-        if (total_samples) {
-                double percent = self->count * 100.0 / total_samples;
-                char *color = PERF_COLOR_NORMAL;
+        he->count++;
 
-                /*
-                 * We color high-overhead entries in red, low-overhead
-                 * entries in green - and keep the middle ground normal:
-                 */
-                if (percent >= 5.0)
-                        color = PERF_COLOR_RED;
-                if (percent < 0.5)
-                        color = PERF_COLOR_GREEN;
+        if (!sym || !sym->hist)
+                return;
 
-                ret = color_fprintf(fp, color, "   %6.2f%%",
-                                (self->count * 100.0) / total_samples);
-        } else
-                ret = fprintf(fp, "%12d ", self->count);
+        sym_size = sym->end - sym->start;
+        offset = ip - sym->start;
 
-        list_for_each_entry(se, &hist_entry__sort_list, list) {
-                fprintf(fp, "  ");
-                ret += se->print(fp, self);
-        }
+        if (offset >= sym_size)
+                return;
 
-        ret += fprintf(fp, "\n");
+        sym->hist_sum++;
+        sym->hist[offset]++;
 
-        return ret;
+        if (verbose >= 3)
+                printf("%p %s: count++ [ip: %p, %08Lx] => %Ld\n",
+                        (void *)he->sym->start,
+                        he->sym->name,
+                        (void *)ip, ip - he->sym->start,
+                        sym->hist[offset]);
 }
 
-/*
- * collect histogram counts
- */
-
 static int
 hist_entry__add(struct thread *thread, struct map *map, struct dso *dso,
                 struct symbol *sym, uint64_t ip, char level)
@@ -732,7 +699,8 @@ hist_entry__add(struct thread *thread, struct map *map, struct dso *dso,
                 cmp = hist_entry__cmp(&entry, he);
 
                 if (!cmp) {
-                        he->count++;
+                        hist_hit(he, ip);
+
                         return 0;
                 }
 
@@ -856,50 +824,6 @@ static void output__resort(void)
         }
 }
 
-static size_t output__fprintf(FILE *fp, uint64_t total_samples)
-{
-        struct hist_entry *pos;
-        struct sort_entry *se;
-        struct rb_node *nd;
-        size_t ret = 0;
-
-        fprintf(fp, "\n");
-        fprintf(fp, "#\n");
-        fprintf(fp, "# (%Ld samples)\n", (__u64)total_samples);
-        fprintf(fp, "#\n");
-
-        fprintf(fp, "# Overhead");
-        list_for_each_entry(se, &hist_entry__sort_list, list)
-                fprintf(fp, "  %s", se->header);
-        fprintf(fp, "\n");
-
-        fprintf(fp, "# ........");
-        list_for_each_entry(se, &hist_entry__sort_list, list) {
-                int i;
-
-                fprintf(fp, "  ");
-                for (i = 0; i < strlen(se->header); i++)
-                        fprintf(fp, ".");
-        }
-        fprintf(fp, "\n");
-
-        fprintf(fp, "#\n");
-
-        for (nd = rb_first(&output_hists); nd; nd = rb_next(nd)) {
-                pos = rb_entry(nd, struct hist_entry, rb_node);
-                ret += hist_entry__fprintf(fp, pos, total_samples);
-        }
-
-        if (!strcmp(sort_order, default_sort_order)) {
-                fprintf(fp, "#\n");
-                fprintf(fp, "# (For more details, try: perf annotate --sort comm,dso,symbol)\n");
-                fprintf(fp, "#\n");
-        }
-        fprintf(fp, "\n");
-
-        return ret;
-}
-
 static void register_idle_thread(void)
 {
         struct thread *thread = threads__findnew(0);
@@ -1106,6 +1030,149 @@ process_event(event_t *event, unsigned long offset, unsigned long head)
         return 0;
 }
 
+static int
+parse_line(FILE *file, struct symbol *sym, uint64_t start, uint64_t len)
+{
+        char *line = NULL, *tmp, *tmp2;
+        unsigned int offset;
+        size_t line_len;
+        __u64 line_ip;
+        int ret;
+        char *c;
+
+        if (getline(&line, &line_len, file) < 0)
+                return -1;
+        if (!line)
+                return -1;
+
+        c = strchr(line, '\n');
+        if (c)
+                *c = 0;
+
+        line_ip = -1;
+        offset = 0;
+        ret = -2;
+
+        /*
+         * Strip leading spaces:
+         */
+        tmp = line;
+        while (*tmp) {
+                if (*tmp != ' ')
+                        break;
+                tmp++;
+        }
+
+        if (*tmp) {
+                /*
+                 * Parse hexa addresses followed by ':'
+                 */
+                line_ip = strtoull(tmp, &tmp2, 16);
+                if (*tmp2 != ':')
+                        line_ip = -1;
+        }
+
+        if (line_ip != -1) {
+                unsigned int hits = 0;
+                double percent = 0.0;
+                char *color = PERF_COLOR_NORMAL;
+
+                offset = line_ip - start;
+                if (offset < len)
+                        hits = sym->hist[offset];
+
+                if (sym->hist_sum)
+                        percent = 100.0 * hits / sym->hist_sum;
+
+                /*
+                 * We color high-overhead entries in red, low-overhead
+                 * entries in green - and keep the middle ground normal:
+                 */
+                if (percent >= 5.0)
+                        color = PERF_COLOR_RED;
+                else {
+                        if (percent > 0.5)
+                                color = PERF_COLOR_GREEN;
+                }
+
+                color_fprintf(stdout, color, " %7.2f", percent);
+                printf(" :      ");
+                color_fprintf(stdout, PERF_COLOR_BLUE, "%s\n", line);
+        } else {
+                if (!*line)
+                        printf("         :\n");
+                else
+                        printf("         :      %s\n", line);
+        }
+
+        return 0;
+}
+
+static void annotate_sym(struct dso *dso, struct symbol *sym)
+{
+        char *filename = dso->name;
+        uint64_t start, end, len;
+        char command[PATH_MAX*2];
+        FILE *file;
+
+        if (!filename)
+                return;
+        if (dso == kernel_dso)
+                filename = vmlinux;
+
+        printf("\n------------------------------------------------\n");
+        printf(" Percent |      Source code & Disassembly of %s\n", filename);
+        printf("------------------------------------------------\n");
+
+        if (verbose >= 2)
+                printf("annotating [%p] %30s : [%p] %30s\n", dso, dso->name, sym, sym->name);
+
+        start = sym->obj_start;
+        if (!start)
+                start = sym->start;
+
+        end = start + sym->end - sym->start + 1;
+        len = sym->end - sym->start;
+
+        sprintf(command, "objdump --start-address=0x%016Lx --stop-address=0x%016Lx -dS %s", (__u64)start, (__u64)end, filename);
+
+        if (verbose >= 3)
+                printf("doing: %s\n", command);
+
+        file = popen(command, "r");
+        if (!file)
+                return;
+
+        while (!feof(file)) {
+                if (parse_line(file, sym, start, len) < 0)
+                        break;
+        }
+
+        pclose(file);
+}
+
+static void find_annotations(void)
+{
+        struct rb_node *nd;
+        struct dso *dso;
+        int count = 0;
+
+        list_for_each_entry(dso, &dsos, node) {
+
+                for (nd = rb_first(&dso->syms); nd; nd = rb_next(nd)) {
+                        struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
+
+                        if (sym->hist) {
+                                annotate_sym(dso, sym);
+                                count++;
+                        }
+                }
+        }
+
+        if (!count)
+                printf(" Error: symbol '%s' not present amongst the samples.\n", sym_hist_filter);
+}
+
 static int __cmd_annotate(void)
 {
         int ret, rc = EXIT_FAILURE;
@@ -1140,16 +1207,6 @@ static int __cmd_annotate(void)
                 return EXIT_FAILURE;
         }
 
-        if (!full_paths) {
-                if (getcwd(__cwd, sizeof(__cwd)) == NULL) {
-                        perror("failed to get the current directory");
-                        return EXIT_FAILURE;
-                }
-                cwdlen = strlen(cwd);
-        } else {
-                cwd = NULL;
-                cwdlen = 0;
-        }
 remap:
         buf = (char *)mmap(NULL, page_size * mmap_window, PROT_READ,
                            MAP_SHARED, input, offset);
@@ -1229,7 +1286,8 @@ more:
 
         collapse__resort();
         output__resort();
-        output__fprintf(stdout, total);
+
+        find_annotations();
 
         return rc;
 }
@@ -1242,15 +1300,13 @@ static const char * const annotate_usage[] = {
 static const struct option options[] = {
         OPT_STRING('i', "input", &input_name, "file",
                     "input file name"),
+        OPT_STRING('s', "symbol", &sym_hist_filter, "file",
+                    "symbol to annotate"),
         OPT_BOOLEAN('v', "verbose", &verbose,
                     "be more verbose (show symbol address, etc)"),
         OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
                     "dump raw trace in ASCII"),
         OPT_STRING('k', "vmlinux", &vmlinux, "file", "vmlinux pathname"),
-        OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
-                   "sort by key(s): pid, comm, dso, symbol. Default: pid,symbol"),
-        OPT_BOOLEAN('P', "full-paths", &full_paths,
-                    "Don't shorten the pathnames taking into account the cwd"),
         OPT_END()
 };
 
@@ -1279,10 +1335,18 @@ int cmd_annotate(int argc, const char **argv, const char *prefix)
 
         setup_sorting();
 
-        /*
-         * Any (unrecognized) arguments left?
-         */
-        if (argc)
+        if (argc) {
+                /*
+                 * Special case: if there's an argument left then assume tha
+                 * it's a symbol filter:
+                 */
+                if (argc > 1)
+                        usage_with_options(annotate_usage, options);
+
+                sym_hist_filter = argv[0];
+        }
+
+        if (!sym_hist_filter)
                 usage_with_options(annotate_usage, options);
 
         setup_pager();
diff --git a/Documentation/perf_counter/util/symbol.c b/Documentation/perf_counter/util/symbol.c
index a06bbfba8350..23f4f7b3b83d 100644
--- a/Documentation/perf_counter/util/symbol.c
+++ b/Documentation/perf_counter/util/symbol.c
@@ -7,21 +7,36 @@
 #include <gelf.h>
 #include <elf.h>
 
+const char *sym_hist_filter;
+
 static struct symbol *symbol__new(uint64_t start, uint64_t len,
-                                  const char *name, unsigned int priv_size)
+                                  const char *name, unsigned int priv_size,
+                                  uint64_t obj_start, int verbose)
 {
         size_t namelen = strlen(name) + 1;
-        struct symbol *self = malloc(priv_size + sizeof(*self) + namelen);
+        struct symbol *self = calloc(1, priv_size + sizeof(*self) + namelen);
 
-        if (self != NULL) {
-                if (priv_size) {
-                        memset(self, 0, priv_size);
-                        self = ((void *)self) + priv_size;
-                }
-                self->start = start;
-                self->end   = start + len - 1;
-                memcpy(self->name, name, namelen);
+        if (!self)
+                return NULL;
+
+        if (verbose >= 2)
+                printf("new symbol: %016Lx [%08lx]: %s, hist: %p, obj_start: %p\n",
+                        (__u64)start, len, name, self->hist, (void *)obj_start);
+
+        self->obj_start= obj_start;
+        self->hist = NULL;
+        self->hist_sum = 0;
+
+        if (sym_hist_filter && !strcmp(name, sym_hist_filter))
+                self->hist = calloc(sizeof(__u64), len);
+
+        if (priv_size) {
+                memset(self, 0, priv_size);
+                self = ((void *)self) + priv_size;
         }
+        self->start = start;
+        self->end   = start + len - 1;
+        memcpy(self->name, name, namelen);
 
         return self;
 }
@@ -166,7 +181,7 @@ static int dso__load_kallsyms(struct dso *self, symbol_filter_t filter, int verb
                  * Well fix up the end later, when we have all sorted.
                  */
                 sym = symbol__new(start, 0xdead, line + len + 2,
-                                  self->sym_priv_size);
+                                  self->sym_priv_size, 0, verbose);
 
                 if (sym == NULL)
                         goto out_delete_line;
@@ -272,7 +287,7 @@ static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
 static int dso__synthesize_plt_symbols(struct  dso *self, Elf *elf,
                                        GElf_Ehdr *ehdr, Elf_Scn *scn_dynsym,
                                        GElf_Shdr *shdr_dynsym,
-                                       size_t dynsym_idx)
+                                       size_t dynsym_idx, int verbose)
 {
         uint32_t nr_rel_entries, idx;
         GElf_Sym sym;
@@ -335,7 +350,7 @@ static int dso__synthesize_plt_symbols(struct  dso *self, Elf *elf,
                                  "%s@plt", elf_sym__name(&sym, symstrs));
 
                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
-                                        sympltname, self->sym_priv_size);
+                                        sympltname, self->sym_priv_size, 0, verbose);
                         if (!f)
                                 return -1;
 
@@ -353,7 +368,7 @@ static int dso__synthesize_plt_symbols(struct  dso *self, Elf *elf,
                                  "%s@plt", elf_sym__name(&sym, symstrs));
 
                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
-                                        sympltname, self->sym_priv_size);
+                                        sympltname, self->sym_priv_size, 0, verbose);
                         if (!f)
                                 return -1;
 
@@ -410,7 +425,7 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
         if (sec_dynsym != NULL) {
                 nr = dso__synthesize_plt_symbols(self, elf, &ehdr,
                                                  sec_dynsym, &shdr,
-                                                 dynsym_idx);
+                                                 dynsym_idx, verbose);
                 if (nr < 0)
                         goto out_elf_end;
         }
@@ -444,6 +459,7 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
 
         elf_symtab__for_each_symbol(syms, nr_syms, index, sym) {
                 struct symbol *f;
+                uint64_t obj_start;
 
                 if (!elf_sym__is_function(&sym))
                         continue;
@@ -453,11 +469,13 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
                         goto out_elf_end;
 
                 gelf_getshdr(sec, &shdr);
+                obj_start = sym.st_value;
+
                 sym.st_value -= shdr.sh_addr - shdr.sh_offset;
 
                 f = symbol__new(sym.st_value, sym.st_size,
                                 elf_sym__name(&sym, symstrs),
-                                self->sym_priv_size);
+                                self->sym_priv_size, obj_start, verbose);
                 if (!f)
                         goto out_elf_end;
 
diff --git a/Documentation/perf_counter/util/symbol.h b/Documentation/perf_counter/util/symbol.h
index e23cc3126684..4839d68f14f0 100644
--- a/Documentation/perf_counter/util/symbol.h
+++ b/Documentation/perf_counter/util/symbol.h
@@ -9,6 +9,9 @@ struct symbol {
         struct rb_node  rb_node;
         __u64           start;
         __u64           end;
+        __u64           obj_start;
+        __u64           hist_sum;
+        __u64           *hist;
         char            name[0];
 };
 
@@ -20,6 +23,8 @@ struct dso {
         char             name[0];
 };
 
+const char *sym_hist_filter;
+
 typedef int (*symbol_filter_t)(struct dso *self, struct symbol *sym);
 
 struct dso *dso__new(const char *name, unsigned int sym_priv_size);