const void *data, size_t len)
{
struct blk_io_trace *t;
+ struct ring_buffer_event *event = NULL;
+ int pc = 0;
+ int cpu = smp_processor_id();
+ bool blk_tracer = blk_tracer_enabled;
+
+ if (blk_tracer) {
+ pc = preempt_count();
+ event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK,
+ sizeof(*t) + len,
+ 0, pc);
+ if (!event)
+ return;
+ t = ring_buffer_event_data(event);
+ goto record_it;
+ }
if (!bt->rchan)
return;
t = relay_reserve(bt->rchan, sizeof(*t) + len);
if (t) {
- const int cpu = smp_processor_id();
-
t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION;
t->time = ktime_to_ns(ktime_get());
+record_it:
t->device = bt->dev;
t->action = action;
t->pid = pid;
t->cpu = cpu;
t->pdu_len = len;
memcpy((void *) t + sizeof(*t), data, len);
+
+ if (blk_tracer)
+ trace_buffer_unlock_commit(blk_tr, event, 0, pc);
}
}
unsigned long flags;
char *buf;
- if (blk_tracer_enabled) {
- va_start(args, fmt);
- ftrace_vprintk(fmt, args);
- va_end(args);
- return;
- }
-
- if (!bt->msg_data)
+ if (unlikely(bt->trace_state != Blktrace_running &&
+ !blk_tracer_enabled))
return;
local_irq_save(flags);
unsigned long *sequence;
pid_t pid;
int cpu, pc = 0;
+ bool blk_tracer = blk_tracer_enabled;
- if (unlikely(bt->trace_state != Blktrace_running &&
- !blk_tracer_enabled))
+ if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer))
return;
what |= ddir_act[rw & WRITE];
return;
cpu = raw_smp_processor_id();
- if (blk_tracer_enabled) {
+ if (blk_tracer) {
tracing_record_cmdline(current);
pc = preempt_count();
if (pdu_len)
memcpy((void *) t + sizeof(*t), pdu_data, pdu_len);
- if (blk_tracer_enabled) {
+ if (blk_tracer) {
trace_buffer_unlock_commit(blk_tr, event, 0, pc);
return;
}
static struct dentry *blk_tree_root;
static DEFINE_MUTEX(blk_tree_mutex);
-static void blk_trace_cleanup(struct blk_trace *bt)
+static void blk_trace_free(struct blk_trace *bt)
{
debugfs_remove(bt->msg_file);
debugfs_remove(bt->dropped_file);
free_percpu(bt->sequence);
free_percpu(bt->msg_data);
kfree(bt);
+}
+
+static void blk_trace_cleanup(struct blk_trace *bt)
+{
+ blk_trace_free(bt);
if (atomic_dec_and_test(&blk_probes_ref))
blk_unregister_tracepoints();
}
char *msg;
struct blk_trace *bt;
- if (count > BLK_TN_MAX_MSG)
+ if (count > BLK_TN_MAX_MSG - 1)
return -EINVAL;
- msg = kmalloc(count, GFP_KERNEL);
+ msg = kmalloc(count + 1, GFP_KERNEL);
if (msg == NULL)
return -ENOMEM;
return -EFAULT;
}
+ msg[count] = '\0';
bt = filp->private_data;
__trace_note_message(bt, "%s", msg);
kfree(msg);
if (buts->name[i] == '/')
buts->name[i] = '_';
- ret = -ENOMEM;
bt = kzalloc(sizeof(*bt), GFP_KERNEL);
if (!bt)
- goto err;
+ return -ENOMEM;
+ ret = -ENOMEM;
bt->sequence = alloc_percpu(unsigned long);
if (!bt->sequence)
goto err;
goto err;
}
- if (atomic_add_return(1, &blk_probes_ref) == 1)
+ if (atomic_inc_return(&blk_probes_ref) == 1)
blk_register_tracepoints();
return 0;
err:
- if (bt) {
- if (bt->msg_file)
- debugfs_remove(bt->msg_file);
- if (bt->dropped_file)
- debugfs_remove(bt->dropped_file);
- free_percpu(bt->sequence);
- free_percpu(bt->msg_data);
- if (bt->rchan)
- relay_close(bt->rchan);
- kfree(bt);
- }
+ blk_trace_free(bt);
return ret;
}
int i = 0;
int tc = t->action >> BLK_TC_SHIFT;
+ if (t->action == BLK_TN_MESSAGE) {
+ rwbs[i++] = 'N';
+ goto out;
+ }
+
if (tc & BLK_TC_DISCARD)
rwbs[i++] = 'D';
else if (tc & BLK_TC_WRITE)
rwbs[i++] = 'S';
if (tc & BLK_TC_META)
rwbs[i++] = 'M';
-
+out:
rwbs[i] = '\0';
}
r->sector = be64_to_cpu(sector);
}
-static int blk_log_action_iter(struct trace_iterator *iter, const char *act)
+typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act);
+
+static int blk_log_action_classic(struct trace_iterator *iter, const char *act)
{
char rwbs[6];
unsigned long long ts = iter->ts;
unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC);
unsigned secs = (unsigned long)ts;
- const struct trace_entry *ent = iter->ent;
- const struct blk_io_trace *t = (const struct blk_io_trace *)ent;
+ const struct blk_io_trace *t = te_blk_io_trace(iter->ent);
fill_rwbs(rwbs, t);
return trace_seq_printf(&iter->seq,
"%3d,%-3d %2d %5d.%09lu %5u %2s %3s ",
MAJOR(t->device), MINOR(t->device), iter->cpu,
- secs, nsec_rem, ent->pid, act, rwbs);
+ secs, nsec_rem, iter->ent->pid, act, rwbs);
}
-static int blk_log_action_seq(struct trace_seq *s, const struct blk_io_trace *t,
- const char *act)
+static int blk_log_action(struct trace_iterator *iter, const char *act)
{
char rwbs[6];
+ const struct blk_io_trace *t = te_blk_io_trace(iter->ent);
+
fill_rwbs(rwbs, t);
- return trace_seq_printf(s, "%3d,%-3d %2s %3s ",
+ return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ",
MAJOR(t->device), MINOR(t->device), act, rwbs);
}
get_pdu_int(ent), cmd);
}
+static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent)
+{
+ int ret;
+ const struct blk_io_trace *t = te_blk_io_trace(ent);
+
+ ret = trace_seq_putmem(s, t + 1, t->pdu_len);
+ if (ret)
+ return trace_seq_putc(s, '\n');
+ return ret;
+}
+
/*
* struct tracer operations
*/
static void blk_tracer_start(struct trace_array *tr)
{
- if (atomic_add_return(1, &blk_probes_ref) == 1)
- blk_register_tracepoints();
+ blk_tracer_enabled = true;
trace_flags &= ~TRACE_ITER_CONTEXT_INFO;
}
{
blk_tr = tr;
blk_tracer_start(tr);
- blk_tracer_enabled = true;
return 0;
}
static void blk_tracer_stop(struct trace_array *tr)
{
+ blk_tracer_enabled = false;
trace_flags |= TRACE_ITER_CONTEXT_INFO;
- if (atomic_dec_and_test(&blk_probes_ref))
- blk_unregister_tracepoints();
}
static void blk_tracer_reset(struct trace_array *tr)
{
- if (!atomic_read(&blk_probes_ref))
- return;
-
- blk_tracer_enabled = false;
blk_tracer_stop(tr);
}
[__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap },
};
-static enum print_line_t blk_trace_event_print(struct trace_iterator *iter,
- int flags)
+static enum print_line_t print_one_line(struct trace_iterator *iter,
+ bool classic)
{
struct trace_seq *s = &iter->seq;
- const struct blk_io_trace *t = (struct blk_io_trace *)iter->ent;
- const u16 what = t->action & ((1 << BLK_TC_SHIFT) - 1);
+ const struct blk_io_trace *t;
+ u16 what;
int ret;
+ bool long_act;
+ blk_log_action_t *log_action;
- if (!trace_print_context(iter))
- return TRACE_TYPE_PARTIAL_LINE;
+ t = te_blk_io_trace(iter->ent);
+ what = t->action & ((1 << BLK_TC_SHIFT) - 1);
+ long_act = !!(trace_flags & TRACE_ITER_VERBOSE);
+ log_action = classic ? &blk_log_action_classic : &blk_log_action;
+
+ if (t->action == BLK_TN_MESSAGE) {
+ ret = log_action(iter, long_act ? "message" : "m");
+ if (ret)
+ ret = blk_log_msg(s, iter->ent);
+ goto out;
+ }
if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act)))
ret = trace_seq_printf(s, "Bad pc action %x\n", what);
else {
- const bool long_act = !!(trace_flags & TRACE_ITER_VERBOSE);
- ret = blk_log_action_seq(s, t, what2act[what].act[long_act]);
+ ret = log_action(iter, what2act[what].act[long_act]);
if (ret)
ret = what2act[what].print(s, iter->ent);
}
-
+out:
return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE;
}
+static enum print_line_t blk_trace_event_print(struct trace_iterator *iter,
+ int flags)
+{
+ if (!trace_print_context(iter))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return print_one_line(iter, false);
+}
+
static int blk_trace_synthesize_old_trace(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter)
{
- const struct blk_io_trace *t;
- u16 what;
- int ret;
-
if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC))
return TRACE_TYPE_UNHANDLED;
- t = (const struct blk_io_trace *)iter->ent;
- what = t->action & ((1 << BLK_TC_SHIFT) - 1);
-
- if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act)))
- ret = trace_seq_printf(&iter->seq, "Bad pc action %x\n", what);
- else {
- const bool long_act = !!(trace_flags & TRACE_ITER_VERBOSE);
- ret = blk_log_action_iter(iter, what2act[what].act[long_act]);
- if (ret)
- ret = what2act[what].print(&iter->seq, iter->ent);
- }
-
- return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE;
+ return print_one_line(iter, true);
}
static struct tracer blk_tracer __read_mostly = {
if (bt == NULL)
return -EINVAL;
- kfree(bt);
+ if (atomic_dec_and_test(&blk_probes_ref))
+ blk_unregister_tracepoints();
+
+ blk_trace_free(bt);
return 0;
}
static int blk_trace_setup_queue(struct request_queue *q, dev_t dev)
{
struct blk_trace *old_bt, *bt = NULL;
+ int ret = -ENOMEM;
bt = kzalloc(sizeof(*bt), GFP_KERNEL);
if (!bt)
return -ENOMEM;
+ bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char));
+ if (!bt->msg_data)
+ goto free_bt;
+
bt->dev = dev;
bt->act_mask = (u16)-1;
bt->end_lba = -1ULL;
old_bt = xchg(&q->blk_trace, bt);
if (old_bt != NULL) {
(void)xchg(&q->blk_trace, old_bt);
- kfree(bt);
- return -EBUSY;
+ ret = -EBUSY;
+ goto free_bt;
}
+ if (atomic_inc_return(&blk_probes_ref) == 1)
+ blk_register_tracepoints();
return 0;
+
+free_bt:
+ blk_trace_free(bt);
+ return ret;
}
/*
Code Review / linux-2.6.git / blobdiff