linux/tools/perf/builtin-kmem.c
Ian Munsie 21ef97f05a perf session: Fallback to unordered processing if no sample_id_all
If we are running the new perf on an old kernel without support for
sample_id_all, we should fall back to the old unordered processing of
events. If we didn't than we would *always* process events without
timestamps out of order, whether or not we hit a reordering race. In
other words, instead of there being a chance of not attributing samples
correctly, we would guarantee that samples would not be attributed.

While processing all events without timestamps before events with
timestamps may seem like an intuitive solution, it falls down as
PERF_RECORD_EXIT events would also be processed before any samples.
Even with a workaround for that case, samples before/after an exec would
not be attributed correctly.

This patch allows commands to indicate whether they need to fall back to
unordered processing, so that commands that do not care about timestamps
on every event will not be affected. If we do fallback, this will print
out a warning if report -D was invoked.

This patch adds the test in perf_session__new so that we only need to
test once per session. Commands that do not use an event_ops (such as
record and top) can simply pass NULL in it's place.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <1291951882-sup-6069@au1.ibm.com>
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-12-21 20:17:51 -02:00

778 lines
17 KiB
C

#include "builtin.h"
#include "perf.h"
#include "util/util.h"
#include "util/cache.h"
#include "util/symbol.h"
#include "util/thread.h"
#include "util/header.h"
#include "util/session.h"
#include "util/parse-options.h"
#include "util/trace-event.h"
#include "util/debug.h"
#include <linux/rbtree.h>
struct alloc_stat;
typedef int (*sort_fn_t)(struct alloc_stat *, struct alloc_stat *);
static char const *input_name = "perf.data";
static int alloc_flag;
static int caller_flag;
static int alloc_lines = -1;
static int caller_lines = -1;
static bool raw_ip;
static char default_sort_order[] = "frag,hit,bytes";
static int *cpunode_map;
static int max_cpu_num;
struct alloc_stat {
u64 call_site;
u64 ptr;
u64 bytes_req;
u64 bytes_alloc;
u32 hit;
u32 pingpong;
short alloc_cpu;
struct rb_node node;
};
static struct rb_root root_alloc_stat;
static struct rb_root root_alloc_sorted;
static struct rb_root root_caller_stat;
static struct rb_root root_caller_sorted;
static unsigned long total_requested, total_allocated;
static unsigned long nr_allocs, nr_cross_allocs;
#define PATH_SYS_NODE "/sys/devices/system/node"
static void init_cpunode_map(void)
{
FILE *fp;
int i;
fp = fopen("/sys/devices/system/cpu/kernel_max", "r");
if (!fp) {
max_cpu_num = 4096;
return;
}
if (fscanf(fp, "%d", &max_cpu_num) < 1)
die("Failed to read 'kernel_max' from sysfs");
max_cpu_num++;
cpunode_map = calloc(max_cpu_num, sizeof(int));
if (!cpunode_map)
die("calloc");
for (i = 0; i < max_cpu_num; i++)
cpunode_map[i] = -1;
fclose(fp);
}
static void setup_cpunode_map(void)
{
struct dirent *dent1, *dent2;
DIR *dir1, *dir2;
unsigned int cpu, mem;
char buf[PATH_MAX];
init_cpunode_map();
dir1 = opendir(PATH_SYS_NODE);
if (!dir1)
return;
while ((dent1 = readdir(dir1)) != NULL) {
if (dent1->d_type != DT_DIR ||
sscanf(dent1->d_name, "node%u", &mem) < 1)
continue;
snprintf(buf, PATH_MAX, "%s/%s", PATH_SYS_NODE, dent1->d_name);
dir2 = opendir(buf);
if (!dir2)
continue;
while ((dent2 = readdir(dir2)) != NULL) {
if (dent2->d_type != DT_LNK ||
sscanf(dent2->d_name, "cpu%u", &cpu) < 1)
continue;
cpunode_map[cpu] = mem;
}
}
}
static void insert_alloc_stat(unsigned long call_site, unsigned long ptr,
int bytes_req, int bytes_alloc, int cpu)
{
struct rb_node **node = &root_alloc_stat.rb_node;
struct rb_node *parent = NULL;
struct alloc_stat *data = NULL;
while (*node) {
parent = *node;
data = rb_entry(*node, struct alloc_stat, node);
if (ptr > data->ptr)
node = &(*node)->rb_right;
else if (ptr < data->ptr)
node = &(*node)->rb_left;
else
break;
}
if (data && data->ptr == ptr) {
data->hit++;
data->bytes_req += bytes_req;
data->bytes_alloc += bytes_alloc;
} else {
data = malloc(sizeof(*data));
if (!data)
die("malloc");
data->ptr = ptr;
data->pingpong = 0;
data->hit = 1;
data->bytes_req = bytes_req;
data->bytes_alloc = bytes_alloc;
rb_link_node(&data->node, parent, node);
rb_insert_color(&data->node, &root_alloc_stat);
}
data->call_site = call_site;
data->alloc_cpu = cpu;
}
static void insert_caller_stat(unsigned long call_site,
int bytes_req, int bytes_alloc)
{
struct rb_node **node = &root_caller_stat.rb_node;
struct rb_node *parent = NULL;
struct alloc_stat *data = NULL;
while (*node) {
parent = *node;
data = rb_entry(*node, struct alloc_stat, node);
if (call_site > data->call_site)
node = &(*node)->rb_right;
else if (call_site < data->call_site)
node = &(*node)->rb_left;
else
break;
}
if (data && data->call_site == call_site) {
data->hit++;
data->bytes_req += bytes_req;
data->bytes_alloc += bytes_alloc;
} else {
data = malloc(sizeof(*data));
if (!data)
die("malloc");
data->call_site = call_site;
data->pingpong = 0;
data->hit = 1;
data->bytes_req = bytes_req;
data->bytes_alloc = bytes_alloc;
rb_link_node(&data->node, parent, node);
rb_insert_color(&data->node, &root_caller_stat);
}
}
static void process_alloc_event(void *data,
struct event *event,
int cpu,
u64 timestamp __used,
struct thread *thread __used,
int node)
{
unsigned long call_site;
unsigned long ptr;
int bytes_req;
int bytes_alloc;
int node1, node2;
ptr = raw_field_value(event, "ptr", data);
call_site = raw_field_value(event, "call_site", data);
bytes_req = raw_field_value(event, "bytes_req", data);
bytes_alloc = raw_field_value(event, "bytes_alloc", data);
insert_alloc_stat(call_site, ptr, bytes_req, bytes_alloc, cpu);
insert_caller_stat(call_site, bytes_req, bytes_alloc);
total_requested += bytes_req;
total_allocated += bytes_alloc;
if (node) {
node1 = cpunode_map[cpu];
node2 = raw_field_value(event, "node", data);
if (node1 != node2)
nr_cross_allocs++;
}
nr_allocs++;
}
static int ptr_cmp(struct alloc_stat *, struct alloc_stat *);
static int callsite_cmp(struct alloc_stat *, struct alloc_stat *);
static struct alloc_stat *search_alloc_stat(unsigned long ptr,
unsigned long call_site,
struct rb_root *root,
sort_fn_t sort_fn)
{
struct rb_node *node = root->rb_node;
struct alloc_stat key = { .ptr = ptr, .call_site = call_site };
while (node) {
struct alloc_stat *data;
int cmp;
data = rb_entry(node, struct alloc_stat, node);
cmp = sort_fn(&key, data);
if (cmp < 0)
node = node->rb_left;
else if (cmp > 0)
node = node->rb_right;
else
return data;
}
return NULL;
}
static void process_free_event(void *data,
struct event *event,
int cpu,
u64 timestamp __used,
struct thread *thread __used)
{
unsigned long ptr;
struct alloc_stat *s_alloc, *s_caller;
ptr = raw_field_value(event, "ptr", data);
s_alloc = search_alloc_stat(ptr, 0, &root_alloc_stat, ptr_cmp);
if (!s_alloc)
return;
if (cpu != s_alloc->alloc_cpu) {
s_alloc->pingpong++;
s_caller = search_alloc_stat(0, s_alloc->call_site,
&root_caller_stat, callsite_cmp);
assert(s_caller);
s_caller->pingpong++;
}
s_alloc->alloc_cpu = -1;
}
static void
process_raw_event(event_t *raw_event __used, void *data,
int cpu, u64 timestamp, struct thread *thread)
{
struct event *event;
int type;
type = trace_parse_common_type(data);
event = trace_find_event(type);
if (!strcmp(event->name, "kmalloc") ||
!strcmp(event->name, "kmem_cache_alloc")) {
process_alloc_event(data, event, cpu, timestamp, thread, 0);
return;
}
if (!strcmp(event->name, "kmalloc_node") ||
!strcmp(event->name, "kmem_cache_alloc_node")) {
process_alloc_event(data, event, cpu, timestamp, thread, 1);
return;
}
if (!strcmp(event->name, "kfree") ||
!strcmp(event->name, "kmem_cache_free")) {
process_free_event(data, event, cpu, timestamp, thread);
return;
}
}
static int process_sample_event(event_t *event, struct sample_data *sample,
struct perf_session *session)
{
struct thread *thread = perf_session__findnew(session, event->ip.pid);
if (thread == NULL) {
pr_debug("problem processing %d event, skipping it.\n",
event->header.type);
return -1;
}
dump_printf(" ... thread: %s:%d\n", thread->comm, thread->pid);
process_raw_event(event, sample->raw_data, sample->cpu,
sample->time, thread);
return 0;
}
static struct perf_event_ops event_ops = {
.sample = process_sample_event,
.comm = event__process_comm,
.ordered_samples = true,
};
static double fragmentation(unsigned long n_req, unsigned long n_alloc)
{
if (n_alloc == 0)
return 0.0;
else
return 100.0 - (100.0 * n_req / n_alloc);
}
static void __print_result(struct rb_root *root, struct perf_session *session,
int n_lines, int is_caller)
{
struct rb_node *next;
struct machine *machine;
printf("%.102s\n", graph_dotted_line);
printf(" %-34s |", is_caller ? "Callsite": "Alloc Ptr");
printf(" Total_alloc/Per | Total_req/Per | Hit | Ping-pong | Frag\n");
printf("%.102s\n", graph_dotted_line);
next = rb_first(root);
machine = perf_session__find_host_machine(session);
if (!machine) {
pr_err("__print_result: couldn't find kernel information\n");
return;
}
while (next && n_lines--) {
struct alloc_stat *data = rb_entry(next, struct alloc_stat,
node);
struct symbol *sym = NULL;
struct map *map;
char buf[BUFSIZ];
u64 addr;
if (is_caller) {
addr = data->call_site;
if (!raw_ip)
sym = machine__find_kernel_function(machine, addr, &map, NULL);
} else
addr = data->ptr;
if (sym != NULL)
snprintf(buf, sizeof(buf), "%s+%Lx", sym->name,
addr - map->unmap_ip(map, sym->start));
else
snprintf(buf, sizeof(buf), "%#Lx", addr);
printf(" %-34s |", buf);
printf(" %9llu/%-5lu | %9llu/%-5lu | %8lu | %8lu | %6.3f%%\n",
(unsigned long long)data->bytes_alloc,
(unsigned long)data->bytes_alloc / data->hit,
(unsigned long long)data->bytes_req,
(unsigned long)data->bytes_req / data->hit,
(unsigned long)data->hit,
(unsigned long)data->pingpong,
fragmentation(data->bytes_req, data->bytes_alloc));
next = rb_next(next);
}
if (n_lines == -1)
printf(" ... | ... | ... | ... | ... | ... \n");
printf("%.102s\n", graph_dotted_line);
}
static void print_summary(void)
{
printf("\nSUMMARY\n=======\n");
printf("Total bytes requested: %lu\n", total_requested);
printf("Total bytes allocated: %lu\n", total_allocated);
printf("Total bytes wasted on internal fragmentation: %lu\n",
total_allocated - total_requested);
printf("Internal fragmentation: %f%%\n",
fragmentation(total_requested, total_allocated));
printf("Cross CPU allocations: %lu/%lu\n", nr_cross_allocs, nr_allocs);
}
static void print_result(struct perf_session *session)
{
if (caller_flag)
__print_result(&root_caller_sorted, session, caller_lines, 1);
if (alloc_flag)
__print_result(&root_alloc_sorted, session, alloc_lines, 0);
print_summary();
}
struct sort_dimension {
const char name[20];
sort_fn_t cmp;
struct list_head list;
};
static LIST_HEAD(caller_sort);
static LIST_HEAD(alloc_sort);
static void sort_insert(struct rb_root *root, struct alloc_stat *data,
struct list_head *sort_list)
{
struct rb_node **new = &(root->rb_node);
struct rb_node *parent = NULL;
struct sort_dimension *sort;
while (*new) {
struct alloc_stat *this;
int cmp = 0;
this = rb_entry(*new, struct alloc_stat, node);
parent = *new;
list_for_each_entry(sort, sort_list, list) {
cmp = sort->cmp(data, this);
if (cmp)
break;
}
if (cmp > 0)
new = &((*new)->rb_left);
else
new = &((*new)->rb_right);
}
rb_link_node(&data->node, parent, new);
rb_insert_color(&data->node, root);
}
static void __sort_result(struct rb_root *root, struct rb_root *root_sorted,
struct list_head *sort_list)
{
struct rb_node *node;
struct alloc_stat *data;
for (;;) {
node = rb_first(root);
if (!node)
break;
rb_erase(node, root);
data = rb_entry(node, struct alloc_stat, node);
sort_insert(root_sorted, data, sort_list);
}
}
static void sort_result(void)
{
__sort_result(&root_alloc_stat, &root_alloc_sorted, &alloc_sort);
__sort_result(&root_caller_stat, &root_caller_sorted, &caller_sort);
}
static int __cmd_kmem(void)
{
int err = -EINVAL;
struct perf_session *session = perf_session__new(input_name, O_RDONLY,
0, false, &event_ops);
if (session == NULL)
return -ENOMEM;
if (perf_session__create_kernel_maps(session) < 0)
goto out_delete;
if (!perf_session__has_traces(session, "kmem record"))
goto out_delete;
setup_pager();
err = perf_session__process_events(session, &event_ops);
if (err != 0)
goto out_delete;
sort_result();
print_result(session);
out_delete:
perf_session__delete(session);
return err;
}
static const char * const kmem_usage[] = {
"perf kmem [<options>] {record|stat}",
NULL
};
static int ptr_cmp(struct alloc_stat *l, struct alloc_stat *r)
{
if (l->ptr < r->ptr)
return -1;
else if (l->ptr > r->ptr)
return 1;
return 0;
}
static struct sort_dimension ptr_sort_dimension = {
.name = "ptr",
.cmp = ptr_cmp,
};
static int callsite_cmp(struct alloc_stat *l, struct alloc_stat *r)
{
if (l->call_site < r->call_site)
return -1;
else if (l->call_site > r->call_site)
return 1;
return 0;
}
static struct sort_dimension callsite_sort_dimension = {
.name = "callsite",
.cmp = callsite_cmp,
};
static int hit_cmp(struct alloc_stat *l, struct alloc_stat *r)
{
if (l->hit < r->hit)
return -1;
else if (l->hit > r->hit)
return 1;
return 0;
}
static struct sort_dimension hit_sort_dimension = {
.name = "hit",
.cmp = hit_cmp,
};
static int bytes_cmp(struct alloc_stat *l, struct alloc_stat *r)
{
if (l->bytes_alloc < r->bytes_alloc)
return -1;
else if (l->bytes_alloc > r->bytes_alloc)
return 1;
return 0;
}
static struct sort_dimension bytes_sort_dimension = {
.name = "bytes",
.cmp = bytes_cmp,
};
static int frag_cmp(struct alloc_stat *l, struct alloc_stat *r)
{
double x, y;
x = fragmentation(l->bytes_req, l->bytes_alloc);
y = fragmentation(r->bytes_req, r->bytes_alloc);
if (x < y)
return -1;
else if (x > y)
return 1;
return 0;
}
static struct sort_dimension frag_sort_dimension = {
.name = "frag",
.cmp = frag_cmp,
};
static int pingpong_cmp(struct alloc_stat *l, struct alloc_stat *r)
{
if (l->pingpong < r->pingpong)
return -1;
else if (l->pingpong > r->pingpong)
return 1;
return 0;
}
static struct sort_dimension pingpong_sort_dimension = {
.name = "pingpong",
.cmp = pingpong_cmp,
};
static struct sort_dimension *avail_sorts[] = {
&ptr_sort_dimension,
&callsite_sort_dimension,
&hit_sort_dimension,
&bytes_sort_dimension,
&frag_sort_dimension,
&pingpong_sort_dimension,
};
#define NUM_AVAIL_SORTS \
(int)(sizeof(avail_sorts) / sizeof(struct sort_dimension *))
static int sort_dimension__add(const char *tok, struct list_head *list)
{
struct sort_dimension *sort;
int i;
for (i = 0; i < NUM_AVAIL_SORTS; i++) {
if (!strcmp(avail_sorts[i]->name, tok)) {
sort = malloc(sizeof(*sort));
if (!sort)
die("malloc");
memcpy(sort, avail_sorts[i], sizeof(*sort));
list_add_tail(&sort->list, list);
return 0;
}
}
return -1;
}
static int setup_sorting(struct list_head *sort_list, const char *arg)
{
char *tok;
char *str = strdup(arg);
if (!str)
die("strdup");
while (true) {
tok = strsep(&str, ",");
if (!tok)
break;
if (sort_dimension__add(tok, sort_list) < 0) {
error("Unknown --sort key: '%s'", tok);
return -1;
}
}
free(str);
return 0;
}
static int parse_sort_opt(const struct option *opt __used,
const char *arg, int unset __used)
{
if (!arg)
return -1;
if (caller_flag > alloc_flag)
return setup_sorting(&caller_sort, arg);
else
return setup_sorting(&alloc_sort, arg);
return 0;
}
static int parse_caller_opt(const struct option *opt __used,
const char *arg __used, int unset __used)
{
caller_flag = (alloc_flag + 1);
return 0;
}
static int parse_alloc_opt(const struct option *opt __used,
const char *arg __used, int unset __used)
{
alloc_flag = (caller_flag + 1);
return 0;
}
static int parse_line_opt(const struct option *opt __used,
const char *arg, int unset __used)
{
int lines;
if (!arg)
return -1;
lines = strtoul(arg, NULL, 10);
if (caller_flag > alloc_flag)
caller_lines = lines;
else
alloc_lines = lines;
return 0;
}
static const struct option kmem_options[] = {
OPT_STRING('i', "input", &input_name, "file",
"input file name"),
OPT_CALLBACK_NOOPT(0, "caller", NULL, NULL,
"show per-callsite statistics",
parse_caller_opt),
OPT_CALLBACK_NOOPT(0, "alloc", NULL, NULL,
"show per-allocation statistics",
parse_alloc_opt),
OPT_CALLBACK('s', "sort", NULL, "key[,key2...]",
"sort by keys: ptr, call_site, bytes, hit, pingpong, frag",
parse_sort_opt),
OPT_CALLBACK('l', "line", NULL, "num",
"show n lines",
parse_line_opt),
OPT_BOOLEAN(0, "raw-ip", &raw_ip, "show raw ip instead of symbol"),
OPT_END()
};
static const char *record_args[] = {
"record",
"-a",
"-R",
"-f",
"-c", "1",
"-e", "kmem:kmalloc",
"-e", "kmem:kmalloc_node",
"-e", "kmem:kfree",
"-e", "kmem:kmem_cache_alloc",
"-e", "kmem:kmem_cache_alloc_node",
"-e", "kmem:kmem_cache_free",
};
static int __cmd_record(int argc, const char **argv)
{
unsigned int rec_argc, i, j;
const char **rec_argv;
rec_argc = ARRAY_SIZE(record_args) + argc - 1;
rec_argv = calloc(rec_argc + 1, sizeof(char *));
if (rec_argv == NULL)
return -ENOMEM;
for (i = 0; i < ARRAY_SIZE(record_args); i++)
rec_argv[i] = strdup(record_args[i]);
for (j = 1; j < (unsigned int)argc; j++, i++)
rec_argv[i] = argv[j];
return cmd_record(i, rec_argv, NULL);
}
int cmd_kmem(int argc, const char **argv, const char *prefix __used)
{
argc = parse_options(argc, argv, kmem_options, kmem_usage, 0);
if (!argc)
usage_with_options(kmem_usage, kmem_options);
symbol__init();
if (!strncmp(argv[0], "rec", 3)) {
return __cmd_record(argc, argv);
} else if (!strcmp(argv[0], "stat")) {
setup_cpunode_map();
if (list_empty(&caller_sort))
setup_sorting(&caller_sort, default_sort_order);
if (list_empty(&alloc_sort))
setup_sorting(&alloc_sort, default_sort_order);
return __cmd_kmem();
} else
usage_with_options(kmem_usage, kmem_options);
return 0;
}