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authorHitoshi Mitake <mitake@dcl.info.waseda.ac.jp>2010-01-30 20:43:33 +0900
committerIngo Molnar <mingo@elte.hu>2010-01-31 09:08:26 +0100
commit9b5e350c7a46a471d5b452836dbafe9aeaeca435 (patch)
treee9c434ba978ad35712941a2531e3741a03361215 /tools
parentc965be10ca3cb0bdd04016c852764afaf8e647c8 (diff)
perf lock: Introduce new tool "perf lock", for analyzing lock statistics
Adding new subcommand "perf lock" to perf. I have a lot of remaining ToDos, but for now perf lock can already provide minimal functionality for analyzing lock statistics. Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1264851813-8413-12-git-send-email-mitake@dcl.info.waseda.ac.jp> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'tools')
-rw-r--r--tools/perf/Makefile1
-rw-r--r--tools/perf/builtin-lock.c724
-rw-r--r--tools/perf/builtin.h1
-rw-r--r--tools/perf/perf.c1
4 files changed, 727 insertions, 0 deletions
diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index b2bce1fb4ae..42969303e20 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -456,6 +456,7 @@ BUILTIN_OBJS += builtin-top.o
BUILTIN_OBJS += builtin-trace.o
BUILTIN_OBJS += builtin-probe.o
BUILTIN_OBJS += builtin-kmem.o
+BUILTIN_OBJS += builtin-lock.o
PERFLIBS = $(LIB_FILE)
diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
new file mode 100644
index 00000000000..2b5f88754c2
--- /dev/null
+++ b/tools/perf/builtin-lock.c
@@ -0,0 +1,724 @@
+#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/parse-options.h"
+#include "util/trace-event.h"
+
+#include "util/debug.h"
+#include "util/session.h"
+
+#include <sys/types.h>
+#include <sys/prctl.h>
+#include <semaphore.h>
+#include <pthread.h>
+#include <math.h>
+#include <limits.h>
+
+#include <linux/list.h>
+#include <linux/hash.h>
+
+/* based on kernel/lockdep.c */
+#define LOCKHASH_BITS 12
+#define LOCKHASH_SIZE (1UL << LOCKHASH_BITS)
+
+static struct list_head lockhash_table[LOCKHASH_SIZE];
+
+#define __lockhashfn(key) hash_long((unsigned long)key, LOCKHASH_BITS)
+#define lockhashentry(key) (lockhash_table + __lockhashfn((key)))
+
+#define LOCK_STATE_UNLOCKED 0 /* initial state */
+#define LOCK_STATE_LOCKED 1
+
+struct lock_stat {
+ struct list_head hash_entry;
+ struct rb_node rb; /* used for sorting */
+
+ /* FIXME: raw_field_value() returns unsigned long long,
+ * so address of lockdep_map should be dealed as 64bit.
+ * Is there more better solution? */
+ void *addr; /* address of lockdep_map, used as ID */
+ char *name; /* for strcpy(), we cannot use const */
+ char *file;
+ unsigned int line;
+
+ int state;
+ u64 prev_event_time; /* timestamp of previous event */
+
+ unsigned int nr_acquired;
+ unsigned int nr_acquire;
+ unsigned int nr_contended;
+ unsigned int nr_release;
+
+ /* these times are in nano sec. */
+ u64 wait_time_total;
+ u64 wait_time_min;
+ u64 wait_time_max;
+};
+
+/* build simple key function one is bigger than two */
+#define SINGLE_KEY(member) \
+ static int lock_stat_key_ ## member(struct lock_stat *one, \
+ struct lock_stat *two) \
+ { \
+ return one->member > two->member; \
+ }
+
+SINGLE_KEY(nr_acquired)
+SINGLE_KEY(nr_contended)
+SINGLE_KEY(wait_time_total)
+SINGLE_KEY(wait_time_min)
+SINGLE_KEY(wait_time_max)
+
+struct lock_key {
+ /*
+ * name: the value for specify by user
+ * this should be simpler than raw name of member
+ * e.g. nr_acquired -> acquired, wait_time_total -> wait_total
+ */
+ const char *name;
+ int (*key)(struct lock_stat*, struct lock_stat*);
+};
+
+static const char *sort_key = "acquired";
+static int (*compare)(struct lock_stat *, struct lock_stat *);
+
+#define DEF_KEY_LOCK(name, fn_suffix) \
+ { #name, lock_stat_key_ ## fn_suffix }
+struct lock_key keys[] = {
+ DEF_KEY_LOCK(acquired, nr_acquired),
+ DEF_KEY_LOCK(contended, nr_contended),
+ DEF_KEY_LOCK(wait_total, wait_time_total),
+ DEF_KEY_LOCK(wait_min, wait_time_min),
+ DEF_KEY_LOCK(wait_max, wait_time_max),
+
+ /* extra comparisons much complicated should be here */
+
+ { NULL, NULL }
+};
+
+static void select_key(void)
+{
+ int i;
+
+ for (i = 0; keys[i].name; i++) {
+ if (!strcmp(keys[i].name, sort_key)) {
+ compare = keys[i].key;
+ return;
+ }
+ }
+
+ die("Unknown compare key:%s\n", sort_key);
+}
+
+static struct rb_root result; /* place to store sorted data */
+
+static void insert_to_result(struct lock_stat *st,
+ int (*bigger)(struct lock_stat *,
+ struct lock_stat *))
+{
+ struct rb_node **rb = &result.rb_node;
+ struct rb_node *parent = NULL;
+ struct lock_stat *p;
+
+ while (*rb) {
+ p = container_of(*rb, struct lock_stat, rb);
+ parent = *rb;
+
+ if (bigger(st, p))
+ rb = &(*rb)->rb_left;
+ else
+ rb = &(*rb)->rb_right;
+ }
+
+ rb_link_node(&st->rb, parent, rb);
+ rb_insert_color(&st->rb, &result);
+}
+
+/* returns left most element of result, and erase it */
+static struct lock_stat *pop_from_result(void)
+{
+ struct rb_node *node = result.rb_node;
+
+ if (!node)
+ return NULL;
+
+ while (node->rb_left)
+ node = node->rb_left;
+
+ rb_erase(node, &result);
+ return container_of(node, struct lock_stat, rb);
+}
+
+static struct lock_stat *lock_stat_findnew(void *addr, const char *name,
+ const char *file, unsigned int line)
+{
+ struct list_head *entry = lockhashentry(addr);
+ struct lock_stat *ret, *new;
+
+ list_for_each_entry(ret, entry, hash_entry) {
+ if (ret->addr == addr)
+ return ret;
+ }
+
+ new = zalloc(sizeof(struct lock_stat));
+ if (!new)
+ goto alloc_failed;
+
+ new->addr = addr;
+ new->name = zalloc(sizeof(char) * strlen(name) + 1);
+ if (!new->name)
+ goto alloc_failed;
+ strcpy(new->name, name);
+ new->file = zalloc(sizeof(char) * strlen(file) + 1);
+ if (!new->file)
+ goto alloc_failed;
+ strcpy(new->file, file);
+ new->line = line;
+
+ /* LOCK_STATE_UNLOCKED == 0 isn't guaranteed forever */
+ new->state = LOCK_STATE_UNLOCKED;
+ new->wait_time_min = ULLONG_MAX;
+
+ list_add(&new->hash_entry, entry);
+ return new;
+
+alloc_failed:
+ die("memory allocation failed\n");
+}
+
+static char const *input_name = "perf.data";
+
+static int profile_cpu = -1;
+
+struct raw_event_sample {
+ u32 size;
+ char data[0];
+};
+
+struct trace_acquire_event {
+ void *addr;
+ const char *name;
+ const char *file;
+ unsigned int line;
+};
+
+struct trace_acquired_event {
+ void *addr;
+ const char *name;
+ const char *file;
+ unsigned int line;
+};
+
+struct trace_contended_event {
+ void *addr;
+ const char *name;
+ const char *file;
+ unsigned int line;
+};
+
+struct trace_release_event {
+ void *addr;
+ const char *name;
+ const char *file;
+ unsigned int line;
+};
+
+struct trace_lock_handler {
+ void (*acquire_event)(struct trace_acquire_event *,
+ struct event *,
+ int cpu,
+ u64 timestamp,
+ struct thread *thread);
+
+ void (*acquired_event)(struct trace_acquired_event *,
+ struct event *,
+ int cpu,
+ u64 timestamp,
+ struct thread *thread);
+
+ void (*contended_event)(struct trace_contended_event *,
+ struct event *,
+ int cpu,
+ u64 timestamp,
+ struct thread *thread);
+
+ void (*release_event)(struct trace_release_event *,
+ struct event *,
+ int cpu,
+ u64 timestamp,
+ struct thread *thread);
+};
+
+static void prof_lock_acquire_event(struct trace_acquire_event *acquire_event,
+ struct event *__event __used,
+ int cpu __used,
+ u64 timestamp,
+ struct thread *thread __used)
+{
+ struct lock_stat *st;
+
+ st = lock_stat_findnew(acquire_event->addr, acquire_event->name,
+ acquire_event->file, acquire_event->line);
+
+ switch (st->state) {
+ case LOCK_STATE_UNLOCKED:
+ break;
+ case LOCK_STATE_LOCKED:
+ break;
+ default:
+ BUG_ON(1);
+ break;
+ }
+
+ st->prev_event_time = timestamp;
+}
+
+static void prof_lock_acquired_event(struct trace_acquired_event *acquired_event,
+ struct event *__event __used,
+ int cpu __used,
+ u64 timestamp,
+ struct thread *thread __used)
+{
+ struct lock_stat *st;
+
+ st = lock_stat_findnew(acquired_event->addr, acquired_event->name,
+ acquired_event->file, acquired_event->line);
+
+ switch (st->state) {
+ case LOCK_STATE_UNLOCKED:
+ st->state = LOCK_STATE_LOCKED;
+ st->nr_acquired++;
+ break;
+ case LOCK_STATE_LOCKED:
+ break;
+ default:
+ BUG_ON(1);
+ break;
+ }
+
+ st->prev_event_time = timestamp;
+}
+
+static void prof_lock_contended_event(struct trace_contended_event *contended_event,
+ struct event *__event __used,
+ int cpu __used,
+ u64 timestamp,
+ struct thread *thread __used)
+{
+ struct lock_stat *st;
+
+ st = lock_stat_findnew(contended_event->addr, contended_event->name,
+ contended_event->file, contended_event->line);
+
+ switch (st->state) {
+ case LOCK_STATE_UNLOCKED:
+ break;
+ case LOCK_STATE_LOCKED:
+ st->nr_contended++;
+ break;
+ default:
+ BUG_ON(1);
+ break;
+ }
+
+ st->prev_event_time = timestamp;
+}
+
+static void prof_lock_release_event(struct trace_release_event *release_event,
+ struct event *__event __used,
+ int cpu __used,
+ u64 timestamp,
+ struct thread *thread __used)
+{
+ struct lock_stat *st;
+ u64 hold_time;
+
+ st = lock_stat_findnew(release_event->addr, release_event->name,
+ release_event->file, release_event->line);
+
+ switch (st->state) {
+ case LOCK_STATE_UNLOCKED:
+ break;
+ case LOCK_STATE_LOCKED:
+ st->state = LOCK_STATE_UNLOCKED;
+ hold_time = timestamp - st->prev_event_time;
+
+ if (timestamp < st->prev_event_time) {
+ /* terribly, this can happen... */
+ goto end;
+ }
+
+ if (st->wait_time_min > hold_time)
+ st->wait_time_min = hold_time;
+ if (st->wait_time_max < hold_time)
+ st->wait_time_max = hold_time;
+ st->wait_time_total += hold_time;
+
+ st->nr_release++;
+ break;
+ default:
+ BUG_ON(1);
+ break;
+ }
+
+end:
+ st->prev_event_time = timestamp;
+}
+
+/* lock oriented handlers */
+/* TODO: handlers for CPU oriented, thread oriented */
+static struct trace_lock_handler prof_lock_ops = {
+ .acquire_event = prof_lock_acquire_event,
+ .acquired_event = prof_lock_acquired_event,
+ .contended_event = prof_lock_contended_event,
+ .release_event = prof_lock_release_event,
+};
+
+static struct trace_lock_handler *trace_handler;
+
+static void
+process_lock_acquire_event(void *data,
+ struct event *event __used,
+ int cpu __used,
+ u64 timestamp __used,
+ struct thread *thread __used)
+{
+ struct trace_acquire_event acquire_event;
+ u64 tmp; /* this is required for casting... */
+
+ tmp = raw_field_value(event, "lockdep_addr", data);
+ memcpy(&acquire_event.addr, &tmp, sizeof(void *));
+ acquire_event.name = (char *)raw_field_ptr(event, "name", data);
+ acquire_event.file = (char *)raw_field_ptr(event, "file", data);
+ acquire_event.line =
+ (unsigned int)raw_field_value(event, "line", data);
+
+ if (trace_handler->acquire_event) {
+ trace_handler->acquire_event(&acquire_event,
+ event, cpu, timestamp, thread);
+ }
+}
+
+static void
+process_lock_acquired_event(void *data,
+ struct event *event __used,
+ int cpu __used,
+ u64 timestamp __used,
+ struct thread *thread __used)
+{
+ struct trace_acquired_event acquired_event;
+ u64 tmp; /* this is required for casting... */
+
+ tmp = raw_field_value(event, "lockdep_addr", data);
+ memcpy(&acquired_event.addr, &tmp, sizeof(void *));
+ acquired_event.name = (char *)raw_field_ptr(event, "name", data);
+ acquired_event.file = (char *)raw_field_ptr(event, "file", data);
+ acquired_event.line =
+ (unsigned int)raw_field_value(event, "line", data);
+
+ if (trace_handler->acquire_event) {
+ trace_handler->acquired_event(&acquired_event,
+ event, cpu, timestamp, thread);
+ }
+}
+
+static void
+process_lock_contended_event(void *data,
+ struct event *event __used,
+ int cpu __used,
+ u64 timestamp __used,
+ struct thread *thread __used)
+{
+ struct trace_contended_event contended_event;
+ u64 tmp; /* this is required for casting... */
+
+ tmp = raw_field_value(event, "lockdep_addr", data);
+ memcpy(&contended_event.addr, &tmp, sizeof(void *));
+ contended_event.name = (char *)raw_field_ptr(event, "name", data);
+ contended_event.file = (char *)raw_field_ptr(event, "file", data);
+ contended_event.line =
+ (unsigned int)raw_field_value(event, "line", data);
+
+ if (trace_handler->acquire_event) {
+ trace_handler->contended_event(&contended_event,
+ event, cpu, timestamp, thread);
+ }
+}
+
+static void
+process_lock_release_event(void *data,
+ struct event *event __used,
+ int cpu __used,
+ u64 timestamp __used,
+ struct thread *thread __used)
+{
+ struct trace_release_event release_event;
+ u64 tmp; /* this is required for casting... */
+
+ tmp = raw_field_value(event, "lockdep_addr", data);
+ memcpy(&release_event.addr, &tmp, sizeof(void *));
+ release_event.name = (char *)raw_field_ptr(event, "name", data);
+ release_event.file = (char *)raw_field_ptr(event, "file", data);
+ release_event.line =
+ (unsigned int)raw_field_value(event, "line", data);
+
+ if (trace_handler->acquire_event) {
+ trace_handler->release_event(&release_event,
+ event, cpu, timestamp, thread);
+ }
+}
+
+static void
+process_raw_event(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, "lock_acquire"))
+ process_lock_acquire_event(data, event, cpu, timestamp, thread);
+ if (!strcmp(event->name, "lock_acquired"))
+ process_lock_acquired_event(data, event, cpu, timestamp, thread);
+ if (!strcmp(event->name, "lock_contended"))
+ process_lock_contended_event(data, event, cpu, timestamp, thread);
+ if (!strcmp(event->name, "lock_release"))
+ process_lock_release_event(data, event, cpu, timestamp, thread);
+}
+
+static int process_sample_event(event_t *event, struct perf_session *session)
+{
+ struct thread *thread;
+ struct sample_data data;
+
+ bzero(&data, sizeof(struct sample_data));
+ event__parse_sample(event, session->sample_type, &data);
+ thread = perf_session__findnew(session, data.pid);
+
+ /*
+ * FIXME: this causes warn on 32bit environment
+ * because of (void *)data.ip (type of data.ip is u64)
+ */
+/* dump_printf("(IP, %d): %d/%d: %p period: %llu\n", */
+/* event->header.misc, */
+/* data.pid, data.tid, (void *)data.ip, data.period); */
+
+ 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);
+
+ if (profile_cpu != -1 && profile_cpu != (int) data.cpu)
+ return 0;
+
+ process_raw_event(data.raw_data, data.cpu, data.time, thread);
+
+ return 0;
+}
+
+/* TODO: various way to print, coloring, nano or milli sec */
+static void print_result(void)
+{
+ struct lock_stat *st;
+ char cut_name[20];
+
+ printf("%18s ", "ID");
+ printf("%20s ", "Name");
+ printf("%10s ", "acquired");
+ printf("%10s ", "contended");
+
+ printf("%15s ", "total wait (ns)");
+ printf("%15s ", "max wait (ns)");
+ printf("%15s ", "min wait (ns)");
+
+ printf("\n\n");
+
+ while ((st = pop_from_result())) {
+ bzero(cut_name, 20);
+
+ printf("%p ", st->addr);
+
+ if (strlen(st->name) < 16) {
+ /* output raw name */
+ printf("%20s ", st->name);
+ } else {
+ strncpy(cut_name, st->name, 16);
+ cut_name[16] = '.';
+ cut_name[17] = '.';
+ cut_name[18] = '.';
+ cut_name[19] = '\0';
+ /* cut off name for saving output style */
+ printf("%20s ", cut_name);
+ }
+
+ printf("%10u ", st->nr_acquired);
+ printf("%10u ", st->nr_contended);
+
+ printf("%15llu ", st->wait_time_total);
+ printf("%15llu ", st->wait_time_max);
+ printf("%15llu ", st->wait_time_min == ULLONG_MAX ?
+ 0 : st->wait_time_min);
+ printf("\n");
+ }
+}
+
+static void dump_map(void)
+{
+ unsigned int i;
+ struct lock_stat *st;
+
+ for (i = 0; i < LOCKHASH_SIZE; i++) {
+ list_for_each_entry(st, &lockhash_table[i], hash_entry) {
+ printf("%p: %s (src: %s, line: %u)\n",
+ st->addr, st->name, st->file, st->line);
+ }
+ }
+}
+
+static struct perf_event_ops eops = {
+ .sample = process_sample_event,
+ .comm = event__process_comm,
+};
+
+static struct perf_session *session;
+
+static int read_events(void)
+{
+ session = perf_session__new(input_name, O_RDONLY, 0);
+ if (!session)
+ die("Initializing perf session failed\n");
+
+ return perf_session__process_events(session, &eops);
+}
+
+static void sort_result(void)
+{
+ unsigned int i;
+ struct lock_stat *st;
+
+ for (i = 0; i < LOCKHASH_SIZE; i++) {
+ list_for_each_entry(st, &lockhash_table[i], hash_entry) {
+ insert_to_result(st, compare);
+ }
+ }
+}
+
+static void __cmd_prof(void)
+{
+ setup_pager();
+ select_key();
+ read_events();
+ sort_result();
+ print_result();
+}
+
+static const char * const prof_usage[] = {
+ "perf sched prof [<options>]",
+ NULL
+};
+
+static const struct option prof_options[] = {
+ OPT_STRING('k', "key", &sort_key, "acquired",
+ "key for sorting"),
+ /* TODO: type */
+ OPT_END()
+};
+
+static const char * const lock_usage[] = {
+ "perf lock [<options>] {record|trace|prof}",
+ NULL
+};
+
+static const struct option lock_options[] = {
+ OPT_STRING('i', "input", &input_name, "file",
+ "input file name"),
+ 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_END()
+};
+
+static const char *record_args[] = {
+ "record",
+ "-a",
+ "-R",
+ "-M",
+ "-f",
+ "-m", "1024",
+ "-c", "1",
+ "-e", "lock:lock_acquire:r",
+ "-e", "lock:lock_acquired:r",
+ "-e", "lock:lock_contended:r",
+ "-e", "lock:lock_release:r",
+};
+
+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 *));
+
+ 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];
+
+ BUG_ON(i != rec_argc);
+
+ return cmd_record(i, rec_argv, NULL);
+}
+
+int cmd_lock(int argc, const char **argv, const char *prefix __used)
+{
+ unsigned int i;
+
+ symbol__init();
+ for (i = 0; i < LOCKHASH_SIZE; i++)
+ INIT_LIST_HEAD(lockhash_table + i);
+
+ argc = parse_options(argc, argv, lock_options, lock_usage,
+ PARSE_OPT_STOP_AT_NON_OPTION);
+ if (!argc)
+ usage_with_options(lock_usage, lock_options);
+
+ if (!strncmp(argv[0], "rec", 3)) {
+ return __cmd_record(argc, argv);
+ } else if (!strncmp(argv[0], "prof", 4)) {
+ trace_handler = &prof_lock_ops;
+ if (argc) {
+ argc = parse_options(argc, argv,
+ prof_options, prof_usage, 0);
+ if (argc)
+ usage_with_options(prof_usage, prof_options);
+ }
+ __cmd_prof();
+ } else if (!strcmp(argv[0], "trace")) {
+ /* Aliased to 'perf trace' */
+ return cmd_trace(argc, argv, prefix);
+ } else if (!strcmp(argv[0], "map")) {
+ /* recycling prof_lock_ops */
+ trace_handler = &prof_lock_ops;
+ setup_pager();
+ read_events();
+ dump_map();
+ } else {
+ usage_with_options(lock_usage, lock_options);
+ }
+
+ return 0;
+}
diff --git a/tools/perf/builtin.h b/tools/perf/builtin.h
index dee97cfe379..10fe49e7048 100644
--- a/tools/perf/builtin.h
+++ b/tools/perf/builtin.h
@@ -31,5 +31,6 @@ extern int cmd_trace(int argc, const char **argv, const char *prefix);
extern int cmd_version(int argc, const char **argv, const char *prefix);
extern int cmd_probe(int argc, const char **argv, const char *prefix);
extern int cmd_kmem(int argc, const char **argv, const char *prefix);
+extern int cmd_lock(int argc, const char **argv, const char *prefix);
#endif
diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index 109b89b30ce..57cb107c1f1 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -303,6 +303,7 @@ static void handle_internal_command(int argc, const char **argv)
{ "sched", cmd_sched, 0 },
{ "probe", cmd_probe, 0 },
{ "kmem", cmd_kmem, 0 },
+ { "lock", cmd_lock, 0 },
};
unsigned int i;
static const char ext[] = STRIP_EXTENSION;