Add symbol resolution to tracker

This commit is contained in:
Søren Sandmann Pedersen
2009-09-07 20:43:22 -04:00
parent cdc7ce7e12
commit d34a1cf460
3 changed files with 504 additions and 362 deletions

View File

@ -513,7 +513,6 @@ collector_start (Collector *collector,
* starting collection, so the parsing doesn't interfere
* with the profiling.
*/
process_is_kernel_address (0);
for (list = collector->counters; list != NULL; list = list->next)
counter_enable (list->data);
@ -710,6 +709,8 @@ resolve_symbols (StackLink *trace, gint size, gpointer data)
Profile *
collector_create_profile (Collector *collector)
{
return tracker_create_profile (collector->tracker);
ResolveInfo info;
Profile *profile;

289
process.c
View File

@ -485,295 +485,6 @@ find_kernel_binary (void)
return binary;
}
typedef struct
{
gulong address;
char *name;
} KernelSymbol;
static void
parse_kallsym_line (const char *line,
GArray *table)
{
char **tokens = g_strsplit_set (line, " \t", -1);
if (tokens[0] && tokens[1] && tokens[2])
{
glong address;
char *endptr;
address = strtoul (tokens[0], &endptr, 16);
if (*endptr == '\0' &&
(strcmp (tokens[1], "T") == 0 ||
strcmp (tokens[1], "t") == 0))
{
KernelSymbol sym;
sym.address = address;
sym.name = g_strdup (tokens[2]);
g_array_append_val (table, sym);
}
}
g_strfreev (tokens);
}
static gboolean
parse_kallsyms (const char *kallsyms,
GArray *table)
{
const char *sol;
const char *eol;
sol = kallsyms;
eol = strchr (sol, '\n');
while (eol)
{
char *line = g_strndup (sol, eol - sol);
parse_kallsym_line (line, table);
g_free (line);
sol = eol + 1;
eol = strchr (sol, '\n');
}
if (table->len <= 1)
return FALSE;
return TRUE;
}
static int
compare_syms (gconstpointer a, gconstpointer b)
{
const KernelSymbol *sym_a = a;
const KernelSymbol *sym_b = b;
if (sym_a->address > sym_b->address)
return 1;
else if (sym_a->address == sym_b->address)
return 0;
else
return -1;
}
static GArray *
get_kernel_symbols (void)
{
static GArray *kernel_syms;
static gboolean initialized = FALSE;
find_kernel_binary();
if (!initialized)
{
char *kallsyms;
if (g_file_get_contents ("/proc/kallsyms", &kallsyms, NULL, NULL))
{
if (kallsyms)
{
kernel_syms = g_array_new (TRUE, TRUE, sizeof (KernelSymbol));
if (parse_kallsyms (kallsyms, kernel_syms))
{
g_array_sort (kernel_syms, compare_syms);
}
else
{
g_array_free (kernel_syms, TRUE);
kernel_syms = NULL;
}
}
g_free (kallsyms);
}
if (!kernel_syms)
g_print ("Warning: /proc/kallsyms could not be "
"read. Kernel symbols will not be available\n");
initialized = TRUE;
}
return kernel_syms;
}
gboolean
process_is_kernel_address (gulong address)
{
GArray *ksyms = get_kernel_symbols ();
if (ksyms &&
address >= g_array_index (ksyms, KernelSymbol, 0).address &&
address < g_array_index (ksyms, KernelSymbol, ksyms->len - 1).address)
{
return TRUE;
}
return FALSE;
}
static KernelSymbol *
do_lookup (KernelSymbol *symbols,
gulong address,
int first,
int last)
{
if (address >= symbols[last].address)
{
return &(symbols[last]);
}
else if (last - first < 3)
{
while (last >= first)
{
if (address >= symbols[last].address)
return &(symbols[last]);
last--;
}
return NULL;
}
else
{
int mid = (first + last) / 2;
if (symbols[mid].address > address)
return do_lookup (symbols, address, first, mid);
else
return do_lookup (symbols, address, mid, last);
}
}
const char *
process_lookup_kernel_symbol (gulong address,
gulong *offset)
{
GArray *ksyms = get_kernel_symbols ();
KernelSymbol *result;
if (offset)
{
/* If we don't have any offset, just return 1, so it doesn't
* look like a callback
*/
*offset = 1;
}
if (ksyms->len == 0)
return NULL;
result = do_lookup ((KernelSymbol *)ksyms->data, address, 0, ksyms->len - 1);
if (result && offset)
*offset = address - result->address;
return result? result->name : NULL;
}
const char *
process_lookup_symbol (Process *process, gulong address, gulong *offset)
{
static const char *const kernel = "[kernel]";
const BinSymbol *result;
Map *map = process_locate_map (process, address);
/* g_print ("addr: %x\n", address); */
if (offset)
{
/* If we don't have any offset, just return 1, so it doesn't
* look like a callback
*/
*offset = 1;
}
if (address == 0x1)
{
return kernel;
}
else if (!map)
{
if (!process->undefined)
{
process->undefined =
g_strdup_printf ("No map (%s)", process->cmdline);
}
return process->undefined;
}
#if 0
if (strcmp (map->filename, "/home/ssp/sysprof/sysprof") == 0)
{
g_print ("YES\n");
g_print ("map address: %lx\n", map->start);
g_print ("map offset: %lx\n", map->offset);
g_print ("address before: %lx (%s)\n", address, map->filename);
}
g_print ("address before: \n");
#endif
#if 0
g_print ("%s is mapped at %lx + %lx\n", map->filename, map->start, map->offset);
g_print ("incoming address: %lx\n", address);
#endif
address -= map->start;
address += map->offset;
#if 0
if (strcmp (map->filename, "[vdso]") == 0)
{
g_print ("address after: %lx\n", address);
}
#endif
if (!map->bin_file)
map->bin_file = bin_file_new (map->filename);
/* g_print ("%s: start: %p, load: %p\n", */
/* map->filename, map->start, bin_file_get_load_address (map->bin_file)); */
if (!bin_file_check_inode (map->bin_file, map->inode))
{
/* If the inodes don't match, it's probably because the
* file has changed since the process was started. Just return
* the undefined symbol in that case.
*/
address = 0x0;
}
result = bin_file_lookup_symbol (map->bin_file, address);
#if 0
g_print (" ---> %s\n", result->name);
#endif
/* g_print ("(%x) %x %x name; %s\n", address, map->start,
* map->offset, result->name);
*/
#if 0
g_print ("name: %s (in %s)\n", bin_symbol_get_name (map->bin_file, result), map->filename);
g_print (" in addr: %lx\n", address);
g_print (" out addr: %lx\n", bin_symbol_get_address (map->bin_file, result));
g_print (" map start: %lx\n", map->start);
g_print (" map offset: %lx\n", map->offset);
#endif
if (offset)
*offset = address - bin_symbol_get_address (map->bin_file, result);
return bin_symbol_get_name (map->bin_file, result);
}
const char *
process_get_cmdline (Process *process)
{

574
tracker.c
View File

@ -6,6 +6,8 @@
#include "tracker.h"
#include "stackstash.h"
#include "binfile.h"
#include "elfparser.h"
#include "perf_counter.h"
typedef struct new_process_t new_process_t;
typedef struct new_map_t new_map_t;
@ -14,7 +16,7 @@ typedef struct sample_t sample_t;
struct tracker_t
{
StackStash *stash;
size_t n_event_bytes;
size_t n_allocated_bytes;
uint8_t * events;
@ -54,41 +56,22 @@ struct sample_t
#define DEFAULT_SIZE (1024 * 1024 * 4)
static void
tracker_append (tracker_t *tracker,
void *event,
int n_bytes)
{
if (tracker->n_allocated_bytes - tracker->n_event_bytes < n_bytes)
{
size_t new_size = tracker->n_allocated_bytes * 2;
tracker->events = g_realloc (tracker->events, new_size);
tracker->n_allocated_bytes = new_size;
}
g_assert (tracker->n_allocated_bytes - tracker->n_event_bytes >= n_bytes);
memcpy (tracker->events + tracker->n_event_bytes, event, n_bytes);
}
static char **
get_lines (const char *format, pid_t pid)
{
char *filename = g_strdup_printf (format, pid);
char **result = NULL;
char *contents;
if (g_file_get_contents (filename, &contents, NULL, NULL))
{
result = g_strsplit (contents, "\n", -1);
g_free (contents);
}
g_free (filename);
return result;
}
@ -96,11 +79,11 @@ static void
fake_new_process (tracker_t *tracker, pid_t pid)
{
char **lines;
if ((lines = get_lines ("/proc/%d/status", pid)))
{
int i;
for (i = 0; lines[i] != NULL; ++i)
{
if (strncmp ("Name:", lines[i], 5) == 0)
@ -109,7 +92,7 @@ fake_new_process (tracker_t *tracker, pid_t pid)
break;
}
}
g_strfreev (lines);
}
}
@ -118,11 +101,11 @@ static void
fake_new_map (tracker_t *tracker, pid_t pid)
{
char **lines;
if ((lines = get_lines ("/proc/%d/maps", pid)))
{
int i;
for (i = 0; lines[i] != NULL; ++i)
{
char file[256];
@ -131,13 +114,13 @@ fake_new_map (tracker_t *tracker, pid_t pid)
gulong offset;
gulong inode;
int count;
file[255] = '\0';
count = sscanf (
lines[i], "%lx-%lx %*15s %lx %*x:%*x %lu %255s",
&start, &end, &offset, &inode, file);
if (count == 5)
{
if (strcmp (file, "[vdso]") == 0)
@ -151,11 +134,11 @@ fake_new_map (tracker_t *tracker, pid_t pid)
offset = 0;
inode = 0;
}
tracker_add_map (tracker, pid, start, end, offset, inode, file);
}
}
g_strfreev (lines);
}
}
@ -165,24 +148,24 @@ populate_from_proc (tracker_t *tracker)
{
GDir *proc = g_dir_open ("/proc", 0, NULL);
const char *name;
if (!proc)
return;
while ((name = g_dir_read_name (proc)))
{
pid_t pid;
char *end;
pid = strtol (name, &end, 10);
if (*end == 0)
{
fake_new_process (tracker, pid);
fake_new_map (tracker, pid);
}
}
g_dir_close (proc);
}
@ -207,21 +190,21 @@ tracker_t *
tracker_new (void)
{
tracker_t *tracker = g_new0 (tracker_t, 1);
tracker->n_event_bytes = 0;
tracker->n_allocated_bytes = DEFAULT_SIZE;
tracker->events = g_malloc (DEFAULT_SIZE);
tracker->stash = stack_stash_new (NULL);
GTimeVal before, after;
g_get_current_time (&before);
populate_from_proc (tracker);
g_get_current_time (&after);
g_print ("Time to populate %f\n", time_diff (&after, &before));
return tracker;
@ -242,7 +225,28 @@ tracker_free (tracker_t *tracker)
dest[sizeof (dest) - 1] = 0; \
} \
while (0)
static void
tracker_append (tracker_t *tracker,
void *event,
int n_bytes)
{
if (tracker->n_allocated_bytes - tracker->n_event_bytes < n_bytes)
{
size_t new_size = tracker->n_allocated_bytes * 2;
tracker->events = g_realloc (tracker->events, new_size);
tracker->n_allocated_bytes = new_size;
}
g_assert (tracker->n_allocated_bytes - tracker->n_event_bytes >= n_bytes);
memcpy (tracker->events + tracker->n_event_bytes, event, n_bytes);
tracker->n_event_bytes += n_bytes;
}
void
tracker_add_process (tracker_t * tracker,
@ -250,13 +254,13 @@ tracker_add_process (tracker_t * tracker,
const char *command_line)
{
new_process_t event;
event.type = NEW_PROCESS;
event.pid = pid;
COPY_STRING (event.command_line, command_line);
tracker_append (tracker, &event, sizeof (event));
#if 0
g_print ("Added new process: %d (%s)\n", pid, command_line);
#endif
@ -272,7 +276,7 @@ tracker_add_map (tracker_t * tracker,
const char *filename)
{
new_map_t event;
event.type = NEW_MAP;
event.pid = pid;
COPY_STRING (event.filename, filename);
@ -280,9 +284,9 @@ tracker_add_map (tracker_t * tracker,
event.end = end;
event.offset = offset;
event.inode = inode;
tracker_append (tracker, &event, sizeof (event));
#if 0
g_print (" Added new map: %d (%s)\n", pid, filename);
#endif
@ -295,11 +299,11 @@ tracker_add_sample (tracker_t *tracker,
int n_ips)
{
sample_t event;
event.type = SAMPLE;
event.pid = pid;
event.trace = stack_stash_add_trace (tracker->stash, ips, n_ips, 1);
tracker_append (tracker, &event, sizeof (event));
}
@ -311,10 +315,10 @@ typedef struct map_t map_t;
struct process_t
{
pid_t pid;
char * comm;
char * undefined;
GPtrArray * maps;
};
@ -325,13 +329,15 @@ struct map_t
uint64_t end;
uint64_t offset;
uint64_t inode;
BinFile * bin_file;
};
struct state_t
{
GHashTable *processes_by_pid;
GHashTable *unique_comms;
GHashTable *unique_symbols;
};
static void
@ -353,22 +359,22 @@ create_map (state_t *state, new_map_t *new_map)
process = g_hash_table_lookup (
state->processes_by_pid, GINT_TO_POINTER (new_map->pid));
if (!process)
return;
map = g_new0 (map_t, 1);
map->filename = g_strdup (new_map->filename);
map->start = new_map->start;
map->end = new_map->end;
map->offset = new_map->offset;
map->inode = new_map->inode;
/* Remove existing maps that overlap the new one */
for (i = 0; i < process->maps->len; ++i)
{
map_t *m = process->maps->pdata[i];
if (m->start < map->end && m->end > map->start)
{
destroy_map (m);
@ -376,7 +382,7 @@ create_map (state_t *state, new_map_t *new_map)
g_ptr_array_remove_index (process->maps, i);
}
}
g_ptr_array_add (process->maps, map);
}
@ -403,12 +409,12 @@ static void
create_process (state_t *state, new_process_t *new_process)
{
process_t *process = g_new0 (process_t, 1);
process->pid = new_process->pid;
process->comm = g_strdup (new_process->command_line);
process->undefined = NULL;
process->maps = g_ptr_array_new ();
g_hash_table_insert (
state->processes_by_pid, GINT_TO_POINTER (process->pid), process);
}
@ -425,16 +431,438 @@ static state_t *
state_new (void)
{
state_t *state = g_new0 (state_t, 1);
state->processes_by_pid =
g_hash_table_new_full (g_direct_hash, g_direct_equal, NULL, free_process);
g_hash_table_new_full (g_direct_hash, g_direct_equal,
NULL, free_process);
state->unique_symbols = g_hash_table_new (g_direct_hash, g_direct_equal);
state->unique_comms = g_hash_table_new (g_str_hash, g_str_equal);
return state;
}
static void
process_sample (state_t *tracker, sample_t *sample)
typedef struct
{
gulong address;
char *name;
} kernel_symbol_t;
static void
parse_kallsym_line (const char *line,
GArray *table)
{
char **tokens = g_strsplit_set (line, " \t", -1);
if (tokens[0] && tokens[1] && tokens[2])
{
glong address;
char *endptr;
address = strtoul (tokens[0], &endptr, 16);
if (*endptr == '\0' &&
(strcmp (tokens[1], "T") == 0 ||
strcmp (tokens[1], "t") == 0))
{
kernel_symbol_t sym;
sym.address = address;
sym.name = g_strdup (tokens[2]);
g_array_append_val (table, sym);
}
}
g_strfreev (tokens);
}
static gboolean
parse_kallsyms (const char *kallsyms,
GArray *table)
{
const char *sol;
const char *eol;
sol = kallsyms;
eol = strchr (sol, '\n');
while (eol)
{
char *line = g_strndup (sol, eol - sol);
parse_kallsym_line (line, table);
g_free (line);
sol = eol + 1;
eol = strchr (sol, '\n');
}
if (table->len <= 1)
return FALSE;
return TRUE;
}
static int
compare_syms (gconstpointer a, gconstpointer b)
{
const kernel_symbol_t *sym_a = a;
const kernel_symbol_t *sym_b = b;
if (sym_a->address > sym_b->address)
return 1;
else if (sym_a->address == sym_b->address)
return 0;
else
return -1;
}
static kernel_symbol_t *
do_lookup (kernel_symbol_t *symbols,
gulong address,
int first,
int last)
{
if (address >= symbols[last].address)
{
return &(symbols[last]);
}
else if (last - first < 3)
{
while (last >= first)
{
if (address >= symbols[last].address)
return &(symbols[last]);
last--;
}
return NULL;
}
else
{
int mid = (first + last) / 2;
if (symbols[mid].address > address)
return do_lookup (symbols, address, first, mid);
else
return do_lookup (symbols, address, mid, last);
}
}
static GArray *
get_kernel_symbols (void)
{
static GArray *kernel_syms;
static gboolean initialized = FALSE;
#if 0
find_kernel_binary();
#endif
if (!initialized)
{
char *kallsyms;
if (g_file_get_contents ("/proc/kallsyms", &kallsyms, NULL, NULL))
{
if (kallsyms)
{
kernel_syms = g_array_new (TRUE, TRUE, sizeof (kernel_symbol_t));
if (parse_kallsyms (kallsyms, kernel_syms))
{
g_array_sort (kernel_syms, compare_syms);
}
else
{
g_array_free (kernel_syms, TRUE);
kernel_syms = NULL;
}
}
g_free (kallsyms);
}
if (!kernel_syms)
g_print ("Warning: /proc/kallsyms could not be "
"read. Kernel symbols will not be available\n");
initialized = TRUE;
}
return kernel_syms;
}
const char *
lookup_kernel_symbol (gulong address)
{
kernel_symbol_t *result;
GArray *ksyms = get_kernel_symbols ();
if (ksyms->len == 0)
return NULL;
result = do_lookup ((kernel_symbol_t *)ksyms->data, address, 0, ksyms->len - 1);
return result? result->name : NULL;
}
/* Note that 'unique_symbols' is a direct_hash table. Ie., we
* rely on the address of symbol strings being different for different
* symbols.
*/
static char *
unique_dup (GHashTable *unique_symbols, const char *sym)
{
char *result;
result = g_hash_table_lookup (unique_symbols, sym);
if (!result)
{
result = elf_demangle (sym);
g_hash_table_insert (unique_symbols, (char *)sym, result);
}
return result;
}
static map_t *
process_locate_map (process_t *process, gulong addr)
{
int i;
for (i = 0; i < process->maps->len; ++i)
{
map_t *map = process->maps->pdata[i];
if (addr >= map->start && addr < map->end)
return map;
}
return NULL;
}
const char *
lookup_user_symbol (process_t *process, gulong address)
{
static const char *const kernel = "[kernel]";
const BinSymbol *result;
map_t *map = process_locate_map (process, address);
#if 0
g_print ("addr: %x\n", address);
#endif
if (address == 0x1)
{
return kernel;
}
else if (!map)
{
if (!process->undefined)
{
process->undefined =
g_strdup_printf ("No map (%s)", process->comm);
}
return process->undefined;
}
#if 0
if (strcmp (map->filename, "/home/ssp/sysprof/sysprof") == 0)
{
g_print ("YES\n");
g_print ("map address: %lx\n", map->start);
g_print ("map offset: %lx\n", map->offset);
g_print ("address before: %lx (%s)\n", address, map->filename);
}
g_print ("address before: \n");
#endif
#if 0
g_print ("%s is mapped at %lx + %lx\n", map->filename, map->start, map->offset);
g_print ("incoming address: %lx\n", address);
#endif
address -= map->start;
address += map->offset;
#if 0
if (strcmp (map->filename, "[vdso]") == 0)
{
g_print ("address after: %lx\n", address);
}
#endif
if (!map->bin_file)
map->bin_file = bin_file_new (map->filename);
/* g_print ("%s: start: %p, load: %p\n", */
/* map->filename, map->start, bin_file_get_load_address (map->bin_file)); */
if (!bin_file_check_inode (map->bin_file, map->inode))
{
/* If the inodes don't match, it's probably because the
* file has changed since the process was started. Just return
* the undefined symbol in that case.
*/
address = 0x0;
}
result = bin_file_lookup_symbol (map->bin_file, address);
#if 0
g_print (" ---> %s\n", result->name);
#endif
/* g_print ("(%x) %x %x name; %s\n", address, map->start,
* map->offset, result->name);
*/
#if 0
g_print ("name: %s (in %s)\n", bin_symbol_get_name (map->bin_file, result), map->filename);
g_print (" in addr: %lx\n", address);
g_print (" out addr: %lx\n", bin_symbol_get_address (map->bin_file, result));
g_print (" map start: %lx\n", map->start);
g_print (" map offset: %lx\n", map->offset);
#endif
return bin_symbol_get_name (map->bin_file, result);
}
static char *
lookup_symbol (state_t *state,
process_t *process,
uint64_t address,
gboolean kernel)
{
const char *sym;
g_assert (process);
if (kernel)
{
sym = lookup_kernel_symbol (address);
}
else
{
sym = lookup_user_symbol (process, address);
}
if (sym)
return unique_dup (state->unique_symbols, sym);
else
return NULL;
}
typedef struct context_info_t context_info_t;
struct context_info_t
{
enum perf_callchain_context context;
char name[32];
};
static const context_info_t context_info[] =
{
{ PERF_CONTEXT_HV, "- - hypervisor - -" },
{ PERF_CONTEXT_KERNEL, "- - kernel - -" },
{ PERF_CONTEXT_USER, "- - user - - " },
{ PERF_CONTEXT_GUEST, "- - guest - - " },
{ PERF_CONTEXT_GUEST_KERNEL, "- - guest kernel - -" },
{ PERF_CONTEXT_GUEST_USER, "- - guest user - -" },
};
static const char *const everything = "[Everything]";
static const context_info_t *
get_context_info (enum perf_callchain_context context)
{
int i;
for (i = 0; i < sizeof (context_info) / sizeof (context_info[0]); ++i)
{
const context_info_t *info = &context_info[i];
if (info->context == context)
return info;
}
return NULL;
}
static void
process_sample (state_t *state, StackStash *resolved, sample_t *sample)
{
const context_info_t *context = NULL;
uint64_t *resolved_traces;
process_t *process;
StackNode *n;
int len;
process = g_hash_table_lookup (
state->processes_by_pid, GINT_TO_POINTER (sample->pid));
if (!process)
{
g_warning ("sample for unknown process %d\n", sample->pid);
return;
}
len = 4;
for (n = sample->trace; n != NULL; n = n->parent)
len++;
resolved_traces = g_new (uint64_t, len);
len = 0;
for (n = sample->trace; n != NULL; n = n->parent)
{
uint64_t address = n->data;
const context_info_t *new_context;
const char *symbol;
new_context = get_context_info (address);
if (new_context)
{
if (context)
symbol = context->name;
else
symbol = NULL;
context = new_context;
}
else
{
gboolean kernel = context && context->context == PERF_CONTEXT_KERNEL;
symbol = lookup_symbol (state, process, address, kernel);
}
if (symbol)
resolved_traces[len++] = POINTER_TO_U64 (symbol);
}
char *cmdline;
cmdline = g_hash_table_lookup (
state->unique_comms, process->comm);
if (!cmdline)
{
cmdline = g_strdup (process->comm);
g_hash_table_insert (state->unique_comms, cmdline, cmdline);
}
resolved_traces[len++] = POINTER_TO_U64 (cmdline);
resolved_traces[len++] = POINTER_TO_U64 (
unique_dup (state->unique_symbols, everything));
stack_stash_add_trace (resolved, resolved_traces, len, 1);
g_free (resolved_traces);
}
Profile *
@ -453,27 +881,29 @@ tracker_create_profile (tracker_t *tracker)
while (event < end)
{
event_type_t type = *(event_type_t *)event;
switch (type)
{
case NEW_PROCESS:
create_process (state, (new_process_t *)event);
event += sizeof (new_process_t);
break;
case NEW_MAP:
create_map (state, (new_map_t *)event);
event += sizeof (new_map_t);
break;
case SAMPLE:
process_sample (state, (sample_t *)event);
process_sample (state, resolved_stash, (sample_t *)event);
event += sizeof (sample_t);
break;
}
}
profile = profile_new (resolved_stash);
stack_stash_unref (resolved_stash);
return profile;
}