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_tr) {
- 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);
{
if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0)
return 1;
- if (sector < bt->start_lba || sector > bt->end_lba)
+ if (sector && (sector < bt->start_lba || sector > bt->end_lba))
return 1;
if (bt->pid && pid != bt->pid)
return 1;
/*
* Data direction bit lookup
*/
-static u32 ddir_act[2] __read_mostly = { BLK_TC_ACT(BLK_TC_READ),
- BLK_TC_ACT(BLK_TC_WRITE) };
+static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ),
+ BLK_TC_ACT(BLK_TC_WRITE) };
/* The ilog2() calls fall out because they're constant */
#define MASK_TC_BIT(rw, __name) ((rw & (1 << BIO_RW_ ## __name)) << \
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];
what |= MASK_TC_BIT(rw, DISCARD);
pid = tsk->pid;
- if (unlikely(act_log_check(bt, what, sector, pid)))
+ if (act_log_check(bt, what, sector, pid))
return;
cpu = raw_smp_processor_id();
- if (blk_tr) {
+ if (blk_tracer) {
tracing_record_cmdline(current);
pc = preempt_count();
if (pdu_len)
memcpy((void *) t + sizeof(*t), pdu_data, pdu_len);
- if (blk_tr) {
+ 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();
}
if (!bt)
return -EINVAL;
- if (bt->trace_state == Blktrace_setup ||
- bt->trace_state == Blktrace_stopped)
+ if (bt->trace_state != Blktrace_running)
blk_trace_cleanup(bt);
return 0;
char *msg;
struct blk_trace *bt;
- if (count > BLK_TN_MAX_MSG)
+ if (count >= BLK_TN_MAX_MSG)
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);
.remove_buf_file = blk_remove_buf_file_callback,
};
+static void blk_trace_setup_lba(struct blk_trace *bt,
+ struct block_device *bdev)
+{
+ struct hd_struct *part = NULL;
+
+ if (bdev)
+ part = bdev->bd_part;
+
+ if (part) {
+ bt->start_lba = part->start_sect;
+ bt->end_lba = part->start_sect + part->nr_sects;
+ } else {
+ bt->start_lba = 0;
+ bt->end_lba = -1ULL;
+ }
+}
+
/*
* Setup everything required to start tracing
*/
int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
- struct blk_user_trace_setup *buts)
+ struct block_device *bdev,
+ struct blk_user_trace_setup *buts)
{
struct blk_trace *old_bt, *bt = NULL;
struct dentry *dir = NULL;
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;
ret = -ENOENT;
+ mutex_lock(&blk_tree_mutex);
if (!blk_tree_root) {
blk_tree_root = debugfs_create_dir("block", NULL);
- if (!blk_tree_root)
+ if (!blk_tree_root) {
+ mutex_unlock(&blk_tree_mutex);
goto err;
+ }
}
+ mutex_unlock(&blk_tree_mutex);
dir = debugfs_create_dir(buts->name, blk_tree_root);
if (!bt->act_mask)
bt->act_mask = (u16) -1;
- bt->start_lba = buts->start_lba;
- bt->end_lba = buts->end_lba;
- if (!bt->end_lba)
- bt->end_lba = -1ULL;
+ blk_trace_setup_lba(bt, bdev);
+
+ /* overwrite with user settings */
+ if (buts->start_lba)
+ bt->start_lba = buts->start_lba;
+ if (buts->end_lba)
+ bt->end_lba = buts->end_lba;
bt->pid = buts->pid;
bt->trace_state = Blktrace_setup;
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 blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
+ struct block_device *bdev,
char __user *arg)
{
struct blk_user_trace_setup buts;
if (ret)
return -EFAULT;
- ret = do_blk_trace_setup(q, name, dev, &buts);
+ ret = do_blk_trace_setup(q, name, dev, bdev, &buts);
if (ret)
return ret;
switch (cmd) {
case BLKTRACESETUP:
bdevname(bdev, b);
- ret = blk_trace_setup(q, b, bdev->bd_dev, arg);
+ ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg);
break;
case BLKTRACESTART:
start = 1;
if (blk_pc_request(rq)) {
what |= BLK_TC_ACT(BLK_TC_PC);
__blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors,
- sizeof(rq->cmd), rq->cmd);
+ rq->cmd_len, rq->cmd);
} else {
what |= BLK_TC_ACT(BLK_TC_FS);
__blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9,
static void fill_rwbs(char *rwbs, const struct blk_io_trace *t)
{
int i = 0;
+ int tc = t->action >> BLK_TC_SHIFT;
- if (t->action & BLK_TC_DISCARD)
+ if (t->action == BLK_TN_MESSAGE) {
+ rwbs[i++] = 'N';
+ goto out;
+ }
+
+ if (tc & BLK_TC_DISCARD)
rwbs[i++] = 'D';
- else if (t->action & BLK_TC_WRITE)
+ else if (tc & BLK_TC_WRITE)
rwbs[i++] = 'W';
else if (t->bytes)
rwbs[i++] = 'R';
else
rwbs[i++] = 'N';
- if (t->action & BLK_TC_AHEAD)
+ if (tc & BLK_TC_AHEAD)
rwbs[i++] = 'A';
- if (t->action & BLK_TC_BARRIER)
+ if (tc & BLK_TC_BARRIER)
rwbs[i++] = 'B';
- if (t->action & BLK_TC_SYNC)
+ if (tc & BLK_TC_SYNC)
rwbs[i++] = 'S';
- if (t->action & BLK_TC_META)
+ if (tc & BLK_TC_META)
rwbs[i++] = 'M';
-
+out:
rwbs[i] = '\0';
}
return te_blk_io_trace(ent) + 1;
}
+static inline u32 t_action(const struct trace_entry *ent)
+{
+ return te_blk_io_trace(ent)->action;
+}
+
+static inline u32 t_bytes(const struct trace_entry *ent)
+{
+ return te_blk_io_trace(ent)->bytes;
+}
+
static inline u32 t_sec(const struct trace_entry *ent)
{
return te_blk_io_trace(ent)->bytes >> 9;
static inline __u16 t_error(const struct trace_entry *ent)
{
- return te_blk_io_trace(ent)->sector;
+ return te_blk_io_trace(ent)->error;
}
static __u64 get_pdu_int(const struct trace_entry *ent)
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 = ns2usecs(iter->ts);
- unsigned long usec_rem = do_div(ts, USEC_PER_SEC);
+ 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.%06lu %5u %2s %3s ",
+ "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ",
MAJOR(t->device), MINOR(t->device), iter->cpu,
- secs, usec_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);
}
+static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent)
+{
+ const char *pdu_buf;
+ int pdu_len;
+ int i, end, ret;
+
+ pdu_buf = pdu_start(ent);
+ pdu_len = te_blk_io_trace(ent)->pdu_len;
+
+ if (!pdu_len)
+ return 1;
+
+ /* find the last zero that needs to be printed */
+ for (end = pdu_len - 1; end >= 0; end--)
+ if (pdu_buf[end])
+ break;
+ end++;
+
+ if (!trace_seq_putc(s, '('))
+ return 0;
+
+ for (i = 0; i < pdu_len; i++) {
+
+ ret = trace_seq_printf(s, "%s%02x",
+ i == 0 ? "" : " ", pdu_buf[i]);
+ if (!ret)
+ return ret;
+
+ /*
+ * stop when the rest is just zeroes and indicate so
+ * with a ".." appended
+ */
+ if (i == end && end != pdu_len - 1)
+ return trace_seq_puts(s, " ..) ");
+ }
+
+ return trace_seq_puts(s, ") ");
+}
+
static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent)
{
char cmd[TASK_COMM_LEN];
trace_find_cmdline(ent->pid, cmd);
- if (t_sec(ent))
- return trace_seq_printf(s, "%llu + %u [%s]\n",
- t_sector(ent), t_sec(ent), cmd);
- return trace_seq_printf(s, "[%s]\n", cmd);
+ if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) {
+ int ret;
+
+ ret = trace_seq_printf(s, "%u ", t_bytes(ent));
+ if (!ret)
+ return 0;
+ ret = blk_log_dump_pdu(s, ent);
+ if (!ret)
+ return 0;
+ return trace_seq_printf(s, "[%s]\n", cmd);
+ } else {
+ if (t_sec(ent))
+ return trace_seq_printf(s, "%llu + %u [%s]\n",
+ t_sector(ent), t_sec(ent), cmd);
+ return trace_seq_printf(s, "[%s]\n", cmd);
+ }
}
static int blk_log_with_error(struct trace_seq *s,
const struct trace_entry *ent)
{
- if (t_sec(ent))
- return trace_seq_printf(s, "%llu + %u [%d]\n", t_sector(ent),
- t_sec(ent), t_error(ent));
- return trace_seq_printf(s, "%llu [%d]\n", t_sector(ent), t_error(ent));
+ if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) {
+ int ret;
+
+ ret = blk_log_dump_pdu(s, ent);
+ if (ret)
+ return trace_seq_printf(s, "[%d]\n", t_error(ent));
+ return 0;
+ } else {
+ if (t_sec(ent))
+ return trace_seq_printf(s, "%llu + %u [%d]\n",
+ t_sector(ent),
+ t_sec(ent), t_error(ent));
+ return trace_seq_printf(s, "%llu [%d]\n",
+ t_sector(ent), t_error(ent));
+ }
}
static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent)
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);
}
-static struct {
+static const struct {
const char *act[2];
int (*print)(struct trace_seq *s, const struct trace_entry *ent);
-} what2act[] __read_mostly = {
+} what2act[] = {
[__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic },
[__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic },
[__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic },
[__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 (unlikely(what == 0 || what > ARRAY_SIZE(what2act)))
- ret = trace_seq_printf(s, "Bad pc action %x\n", what);
+ 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, "Unknown 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;
const int offset = offsetof(struct blk_io_trace, sector);
struct blk_io_trace old = {
.magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION,
- .time = ns2usecs(iter->ts),
+ .time = iter->ts,
};
if (!trace_seq_putmem(s, &old, offset))
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;
}
/*
* Setup everything required to start tracing
*/
-static int blk_trace_setup_queue(struct request_queue *q, dev_t dev)
+static int blk_trace_setup_queue(struct request_queue *q,
+ struct block_device *bdev)
{
struct blk_trace *old_bt, *bt = NULL;
+ int ret = -ENOMEM;
bt = kzalloc(sizeof(*bt), GFP_KERNEL);
if (!bt)
return -ENOMEM;
- bt->dev = dev;
+ bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char));
+ if (!bt->msg_data)
+ goto free_bt;
+
+ bt->dev = bdev->bd_dev;
bt->act_mask = (u16)-1;
- bt->end_lba = -1ULL;
- bt->trace_state = Blktrace_running;
+
+ blk_trace_setup_lba(bt, bdev);
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;
}
/*
* sysfs interface to enable and configure tracing
*/
-static ssize_t sysfs_blk_trace_enable_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct hd_struct *p = dev_to_part(dev);
- struct block_device *bdev;
- ssize_t ret = -ENXIO;
-
- lock_kernel();
- bdev = bdget(part_devt(p));
- if (bdev != NULL) {
- struct request_queue *q = bdev_get_queue(bdev);
-
- if (q != NULL) {
- mutex_lock(&bdev->bd_mutex);
- ret = sprintf(buf, "%u\n", !!q->blk_trace);
- mutex_unlock(&bdev->bd_mutex);
- }
-
- bdput(bdev);
- }
-
- unlock_kernel();
- return ret;
-}
-
-static ssize_t sysfs_blk_trace_enable_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t count)
-{
- struct block_device *bdev;
- struct request_queue *q;
- struct hd_struct *p;
- int value;
- ssize_t ret = -ENXIO;
-
- if (count == 0 || sscanf(buf, "%d", &value) != 1)
- goto out;
-
- lock_kernel();
- p = dev_to_part(dev);
- bdev = bdget(part_devt(p));
- if (bdev == NULL)
- goto out_unlock_kernel;
-
- q = bdev_get_queue(bdev);
- if (q == NULL)
- goto out_bdput;
-
- mutex_lock(&bdev->bd_mutex);
- if (value)
- ret = blk_trace_setup_queue(q, bdev->bd_dev);
- else
- ret = blk_trace_remove_queue(q);
- mutex_unlock(&bdev->bd_mutex);
-
- if (ret == 0)
- ret = count;
-out_bdput:
- bdput(bdev);
-out_unlock_kernel:
- unlock_kernel();
-out:
- return ret;
-}
-
static ssize_t sysfs_blk_trace_attr_show(struct device *dev,
struct device_attribute *attr,
char *buf);
sysfs_blk_trace_attr_show, \
sysfs_blk_trace_attr_store)
-static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR,
- sysfs_blk_trace_enable_show, sysfs_blk_trace_enable_store);
+static BLK_TRACE_DEVICE_ATTR(enable);
static BLK_TRACE_DEVICE_ATTR(act_mask);
static BLK_TRACE_DEVICE_ATTR(pid);
static BLK_TRACE_DEVICE_ATTR(start_lba);
.attrs = blk_trace_attrs,
};
-static int blk_str2act_mask(const char *str)
+static const struct {
+ int mask;
+ const char *str;
+} mask_maps[] = {
+ { BLK_TC_READ, "read" },
+ { BLK_TC_WRITE, "write" },
+ { BLK_TC_BARRIER, "barrier" },
+ { BLK_TC_SYNC, "sync" },
+ { BLK_TC_QUEUE, "queue" },
+ { BLK_TC_REQUEUE, "requeue" },
+ { BLK_TC_ISSUE, "issue" },
+ { BLK_TC_COMPLETE, "complete" },
+ { BLK_TC_FS, "fs" },
+ { BLK_TC_PC, "pc" },
+ { BLK_TC_AHEAD, "ahead" },
+ { BLK_TC_META, "meta" },
+ { BLK_TC_DISCARD, "discard" },
+ { BLK_TC_DRV_DATA, "drv_data" },
+};
+
+static int blk_trace_str2mask(const char *str)
{
+ int i;
int mask = 0;
- char *copy = kstrdup(str, GFP_KERNEL), *s;
+ char *buf, *s, *token;
- if (copy == NULL)
+ buf = kstrdup(str, GFP_KERNEL);
+ if (buf == NULL)
return -ENOMEM;
-
- s = strstrip(copy);
+ s = strstrip(buf);
while (1) {
- char *sep = strchr(s, ',');
-
- if (sep != NULL)
- *sep = '\0';
-
- if (strcasecmp(s, "barrier") == 0)
- mask |= BLK_TC_BARRIER;
- else if (strcasecmp(s, "complete") == 0)
- mask |= BLK_TC_COMPLETE;
- else if (strcasecmp(s, "fs") == 0)
- mask |= BLK_TC_FS;
- else if (strcasecmp(s, "issue") == 0)
- mask |= BLK_TC_ISSUE;
- else if (strcasecmp(s, "pc") == 0)
- mask |= BLK_TC_PC;
- else if (strcasecmp(s, "queue") == 0)
- mask |= BLK_TC_QUEUE;
- else if (strcasecmp(s, "read") == 0)
- mask |= BLK_TC_READ;
- else if (strcasecmp(s, "requeue") == 0)
- mask |= BLK_TC_REQUEUE;
- else if (strcasecmp(s, "sync") == 0)
- mask |= BLK_TC_SYNC;
- else if (strcasecmp(s, "write") == 0)
- mask |= BLK_TC_WRITE;
-
- if (sep == NULL)
+ token = strsep(&s, ",");
+ if (token == NULL)
break;
- s = sep + 1;
+ if (*token == '\0')
+ continue;
+
+ for (i = 0; i < ARRAY_SIZE(mask_maps); i++) {
+ if (strcasecmp(token, mask_maps[i].str) == 0) {
+ mask |= mask_maps[i].mask;
+ break;
+ }
+ }
+ if (i == ARRAY_SIZE(mask_maps)) {
+ mask = -EINVAL;
+ break;
+ }
}
- kfree(copy);
+ kfree(buf);
return mask;
}
+static ssize_t blk_trace_mask2str(char *buf, int mask)
+{
+ int i;
+ char *p = buf;
+
+ for (i = 0; i < ARRAY_SIZE(mask_maps); i++) {
+ if (mask & mask_maps[i].mask) {
+ p += sprintf(p, "%s%s",
+ (p == buf) ? "" : ",", mask_maps[i].str);
+ }
+ }
+ *p++ = '\n';
+
+ return p - buf;
+}
+
+static struct request_queue *blk_trace_get_queue(struct block_device *bdev)
+{
+ if (bdev->bd_disk == NULL)
+ return NULL;
+
+ return bdev_get_queue(bdev);
+}
+
static ssize_t sysfs_blk_trace_attr_show(struct device *dev,
struct device_attribute *attr,
char *buf)
if (bdev == NULL)
goto out_unlock_kernel;
- q = bdev_get_queue(bdev);
+ q = blk_trace_get_queue(bdev);
if (q == NULL)
goto out_bdput;
+
mutex_lock(&bdev->bd_mutex);
+
+ if (attr == &dev_attr_enable) {
+ ret = sprintf(buf, "%u\n", !!q->blk_trace);
+ goto out_unlock_bdev;
+ }
+
if (q->blk_trace == NULL)
ret = sprintf(buf, "disabled\n");
else if (attr == &dev_attr_act_mask)
- ret = sprintf(buf, "%#x\n", q->blk_trace->act_mask);
+ ret = blk_trace_mask2str(buf, q->blk_trace->act_mask);
else if (attr == &dev_attr_pid)
ret = sprintf(buf, "%u\n", q->blk_trace->pid);
else if (attr == &dev_attr_start_lba)
ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba);
else if (attr == &dev_attr_end_lba)
ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba);
+
+out_unlock_bdev:
mutex_unlock(&bdev->bd_mutex);
out_bdput:
bdput(bdev);
struct request_queue *q;
struct hd_struct *p;
u64 value;
- ssize_t ret = -ENXIO;
+ ssize_t ret = -EINVAL;
if (count == 0)
goto out;
if (attr == &dev_attr_act_mask) {
if (sscanf(buf, "%llx", &value) != 1) {
/* Assume it is a list of trace category names */
- value = blk_str2act_mask(buf);
- if (value < 0)
+ ret = blk_trace_str2mask(buf);
+ if (ret < 0)
goto out;
+ value = ret;
}
} else if (sscanf(buf, "%llu", &value) != 1)
goto out;
+ ret = -ENXIO;
+
lock_kernel();
p = dev_to_part(dev);
bdev = bdget(part_devt(p));
if (bdev == NULL)
goto out_unlock_kernel;
- q = bdev_get_queue(bdev);
+ q = blk_trace_get_queue(bdev);
if (q == NULL)
goto out_bdput;
mutex_lock(&bdev->bd_mutex);
+
+ if (attr == &dev_attr_enable) {
+ if (value)
+ ret = blk_trace_setup_queue(q, bdev);
+ else
+ ret = blk_trace_remove_queue(q);
+ goto out_unlock_bdev;
+ }
+
ret = 0;
if (q->blk_trace == NULL)
- ret = blk_trace_setup_queue(q, bdev->bd_dev);
+ ret = blk_trace_setup_queue(q, bdev);
if (ret == 0) {
if (attr == &dev_attr_act_mask)
q->blk_trace->start_lba = value;
else if (attr == &dev_attr_end_lba)
q->blk_trace->end_lba = value;
- ret = count;
}
+
+out_unlock_bdev:
mutex_unlock(&bdev->bd_mutex);
out_bdput:
bdput(bdev);
out_unlock_kernel:
unlock_kernel();
out:
- return ret;
+ return ret ? ret : count;
+}
+
+int blk_trace_init_sysfs(struct device *dev)
+{
+ return sysfs_create_group(&dev->kobj, &blk_trace_attr_group);
}
+
Code Review / linux-2.6.git / blobdiff