diff options
| -rw-r--r-- | drivers/block/drbd/drbd_debugfs.c | 78 | ||||
| -rw-r--r-- | drivers/block/drbd/drbd_int.h | 26 | ||||
| -rw-r--r-- | drivers/block/drbd/drbd_receiver.c | 6 | ||||
| -rw-r--r-- | drivers/block/drbd/drbd_worker.c | 37 |
4 files changed, 144 insertions, 3 deletions
diff --git a/drivers/block/drbd/drbd_debugfs.c b/drivers/block/drbd/drbd_debugfs.c index 12d072d9751f..230d9e1fc85c 100644 --- a/drivers/block/drbd/drbd_debugfs.c +++ b/drivers/block/drbd/drbd_debugfs.c @@ -521,6 +521,77 @@ void drbd_debugfs_resource_cleanup(struct drbd_resource *resource) drbd_debugfs_remove(&resource->debugfs_res); } +static void seq_print_one_timing_detail(struct seq_file *m, + const struct drbd_thread_timing_details *tdp, + unsigned long now) +{ + struct drbd_thread_timing_details td; + /* No locking... + * use temporary assignment to get at consistent data. */ + do { + td = *tdp; + } while (td.cb_nr != tdp->cb_nr); + if (!td.cb_addr) + return; + seq_printf(m, "%u\t%d\t%s:%u\t%ps\n", + td.cb_nr, + jiffies_to_msecs(now - td.start_jif), + td.caller_fn, td.line, + td.cb_addr); +} + +static void seq_print_timing_details(struct seq_file *m, + const char *title, + unsigned int cb_nr, struct drbd_thread_timing_details *tdp, unsigned long now) +{ + unsigned int start_idx; + unsigned int i; + + seq_printf(m, "%s\n", title); + /* If not much is going on, this will result in natural ordering. + * If it is very busy, we will possibly skip events, or even see wrap + * arounds, which could only be avoided with locking. + */ + start_idx = cb_nr % DRBD_THREAD_DETAILS_HIST; + for (i = start_idx; i < DRBD_THREAD_DETAILS_HIST; i++) + seq_print_one_timing_detail(m, tdp+i, now); + for (i = 0; i < start_idx; i++) + seq_print_one_timing_detail(m, tdp+i, now); +} + +static int callback_history_show(struct seq_file *m, void *ignored) +{ + struct drbd_connection *connection = m->private; + unsigned long jif = jiffies; + + seq_puts(m, "n\tage\tcallsite\tfn\n"); + seq_print_timing_details(m, "worker", connection->w_cb_nr, connection->w_timing_details, jif); + seq_print_timing_details(m, "receiver", connection->r_cb_nr, connection->r_timing_details, jif); + return 0; +} + +static int callback_history_open(struct inode *inode, struct file *file) +{ + struct drbd_connection *connection = inode->i_private; + return drbd_single_open(file, callback_history_show, connection, + &connection->kref, drbd_destroy_connection); +} + +static int callback_history_release(struct inode *inode, struct file *file) +{ + struct drbd_connection *connection = inode->i_private; + kref_put(&connection->kref, drbd_destroy_connection); + return single_release(inode, file); +} + +static const struct file_operations connection_callback_history_fops = { + .owner = THIS_MODULE, + .open = callback_history_open, + .read = seq_read, + .llseek = seq_lseek, + .release = callback_history_release, +}; + void drbd_debugfs_connection_add(struct drbd_connection *connection) { struct dentry *conns_dir = connection->resource->debugfs_res_connections; @@ -535,6 +606,13 @@ void drbd_debugfs_connection_add(struct drbd_connection *connection) if (IS_ERR_OR_NULL(dentry)) goto fail; connection->debugfs_conn = dentry; + + dentry = debugfs_create_file("callback_history", S_IRUSR|S_IRGRP, + connection->debugfs_conn, connection, + &connection_callback_history_fops); + if (IS_ERR_OR_NULL(dentry)) + goto fail; + connection->debugfs_conn_callback_history = dentry; return; fail: diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index 30ed430f57bf..1a000016ccdf 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -697,6 +697,15 @@ struct drbd_resource { cpumask_var_t cpu_mask; }; +struct drbd_thread_timing_details +{ + unsigned long start_jif; + void *cb_addr; + const char *caller_fn; + unsigned int line; + unsigned int cb_nr; +}; + struct drbd_connection { struct list_head connections; struct drbd_resource *resource; @@ -759,6 +768,12 @@ struct drbd_connection { /* sender side */ struct drbd_work_queue sender_work; +#define DRBD_THREAD_DETAILS_HIST 16 + unsigned int w_cb_nr; /* keeps counting up */ + unsigned int r_cb_nr; /* keeps counting up */ + struct drbd_thread_timing_details w_timing_details[DRBD_THREAD_DETAILS_HIST]; + struct drbd_thread_timing_details r_timing_details[DRBD_THREAD_DETAILS_HIST]; + struct { /* whether this sender thread * has processed a single write yet. */ @@ -774,6 +789,17 @@ struct drbd_connection { } send; }; +void __update_timing_details( + struct drbd_thread_timing_details *tdp, + unsigned int *cb_nr, + void *cb, + const char *fn, const unsigned int line); + +#define update_worker_timing_details(c, cb) \ + __update_timing_details(c->w_timing_details, &c->w_cb_nr, cb, __func__ , __LINE__ ) +#define update_receiver_timing_details(c, cb) \ + __update_timing_details(c->r_timing_details, &c->r_cb_nr, cb, __func__ , __LINE__ ) + struct submit_worker { struct workqueue_struct *wq; struct work_struct worker; diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index 9f6ed240e075..f972988291c5 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -2682,9 +2682,11 @@ static int receive_DataRequest(struct drbd_connection *connection, struct packet list_add_tail(&peer_req->w.list, &device->read_ee); spin_unlock_irq(&device->resource->req_lock); + update_receiver_timing_details(connection, drbd_rs_should_slow_down); if (device->state.peer != R_PRIMARY && drbd_rs_should_slow_down(device, sector, false)) schedule_timeout_uninterruptible(HZ/10); + update_receiver_timing_details(connection, drbd_rs_begin_io); if (drbd_rs_begin_io(device, sector)) goto out_free_e; @@ -2692,6 +2694,7 @@ submit_for_resync: atomic_add(size >> 9, &device->rs_sect_ev); submit: + update_receiver_timing_details(connection, drbd_submit_peer_request); inc_unacked(device); if (drbd_submit_peer_request(device, peer_req, READ, fault_type) == 0) return 0; @@ -4601,6 +4604,7 @@ static void drbdd(struct drbd_connection *connection) struct data_cmd *cmd; drbd_thread_current_set_cpu(&connection->receiver); + update_receiver_timing_details(connection, drbd_recv_header); if (drbd_recv_header(connection, &pi)) goto err_out; @@ -4619,12 +4623,14 @@ static void drbdd(struct drbd_connection *connection) } if (shs) { + update_receiver_timing_details(connection, drbd_recv_all_warn); err = drbd_recv_all_warn(connection, pi.data, shs); if (err) goto err_out; pi.size -= shs; } + update_receiver_timing_details(connection, cmd->fn); err = cmd->fn(connection, &pi); if (err) { drbd_err(connection, "error receiving %s, e: %d l: %d!\n", diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c index b908e9b3f63e..50776b362828 100644 --- a/drivers/block/drbd/drbd_worker.c +++ b/drivers/block/drbd/drbd_worker.c @@ -1905,6 +1905,29 @@ static int do_md_sync(struct drbd_device *device) return 0; } +/* only called from drbd_worker thread, no locking */ +void __update_timing_details( + struct drbd_thread_timing_details *tdp, + unsigned int *cb_nr, + void *cb, + const char *fn, const unsigned int line) +{ + unsigned int i = *cb_nr % DRBD_THREAD_DETAILS_HIST; + struct drbd_thread_timing_details *td = tdp + i; + + td->start_jif = jiffies; + td->cb_addr = cb; + td->caller_fn = fn; + td->line = line; + td->cb_nr = *cb_nr; + + i = (i+1) % DRBD_THREAD_DETAILS_HIST; + td = tdp + i; + memset(td, 0, sizeof(*td)); + + ++(*cb_nr); +} + #define WORK_PENDING(work_bit, todo) (todo & (1UL << work_bit)) static void do_device_work(struct drbd_device *device, const unsigned long todo) { @@ -2076,11 +2099,15 @@ int drbd_worker(struct drbd_thread *thi) while (get_t_state(thi) == RUNNING) { drbd_thread_current_set_cpu(thi); - if (list_empty(&work_list)) + if (list_empty(&work_list)) { + update_worker_timing_details(connection, wait_for_work); wait_for_work(connection, &work_list); + } - if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags)) + if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags)) { + update_worker_timing_details(connection, do_unqueued_work); do_unqueued_work(connection); + } if (signal_pending(current)) { flush_signals(current); @@ -2097,6 +2124,7 @@ int drbd_worker(struct drbd_thread *thi) while (!list_empty(&work_list)) { w = list_first_entry(&work_list, struct drbd_work, list); list_del_init(&w->list); + update_worker_timing_details(connection, w->cb); if (w->cb(w, connection->cstate < C_WF_REPORT_PARAMS) == 0) continue; if (connection->cstate >= C_WF_REPORT_PARAMS) @@ -2105,11 +2133,14 @@ int drbd_worker(struct drbd_thread *thi) } do { - if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags)) + if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags)) { + update_worker_timing_details(connection, do_unqueued_work); do_unqueued_work(connection); + } while (!list_empty(&work_list)) { w = list_first_entry(&work_list, struct drbd_work, list); list_del_init(&w->list); + update_worker_timing_details(connection, w->cb); w->cb(w, 1); } dequeue_work_batch(&connection->sender_work, &work_list); |