xref: /openbmc/linux/drivers/block/drbd/drbd_proc.c (revision 82e6fdd6)
1 /*
2    drbd_proc.c
3 
4    This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
5 
6    Copyright (C) 2001-2008, LINBIT Information Technologies GmbH.
7    Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>.
8    Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>.
9 
10    drbd is free software; you can redistribute it and/or modify
11    it under the terms of the GNU General Public License as published by
12    the Free Software Foundation; either version 2, or (at your option)
13    any later version.
14 
15    drbd is distributed in the hope that it will be useful,
16    but WITHOUT ANY WARRANTY; without even the implied warranty of
17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18    GNU General Public License for more details.
19 
20    You should have received a copy of the GNU General Public License
21    along with drbd; see the file COPYING.  If not, write to
22    the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
23 
24  */
25 
26 #include <linux/module.h>
27 
28 #include <linux/uaccess.h>
29 #include <linux/fs.h>
30 #include <linux/file.h>
31 #include <linux/proc_fs.h>
32 #include <linux/seq_file.h>
33 #include <linux/drbd.h>
34 #include "drbd_int.h"
35 
36 static int drbd_proc_open(struct inode *inode, struct file *file);
37 static int drbd_proc_release(struct inode *inode, struct file *file);
38 
39 
40 struct proc_dir_entry *drbd_proc;
41 const struct file_operations drbd_proc_fops = {
42 	.owner		= THIS_MODULE,
43 	.open		= drbd_proc_open,
44 	.read		= seq_read,
45 	.llseek		= seq_lseek,
46 	.release	= drbd_proc_release,
47 };
48 
49 static void seq_printf_with_thousands_grouping(struct seq_file *seq, long v)
50 {
51 	/* v is in kB/sec. We don't expect TiByte/sec yet. */
52 	if (unlikely(v >= 1000000)) {
53 		/* cool: > GiByte/s */
54 		seq_printf(seq, "%ld,", v / 1000000);
55 		v %= 1000000;
56 		seq_printf(seq, "%03ld,%03ld", v/1000, v % 1000);
57 	} else if (likely(v >= 1000))
58 		seq_printf(seq, "%ld,%03ld", v/1000, v % 1000);
59 	else
60 		seq_printf(seq, "%ld", v);
61 }
62 
63 static void drbd_get_syncer_progress(struct drbd_device *device,
64 		union drbd_dev_state state, unsigned long *rs_total,
65 		unsigned long *bits_left, unsigned int *per_mil_done)
66 {
67 	/* this is to break it at compile time when we change that, in case we
68 	 * want to support more than (1<<32) bits on a 32bit arch. */
69 	typecheck(unsigned long, device->rs_total);
70 	*rs_total = device->rs_total;
71 
72 	/* note: both rs_total and rs_left are in bits, i.e. in
73 	 * units of BM_BLOCK_SIZE.
74 	 * for the percentage, we don't care. */
75 
76 	if (state.conn == C_VERIFY_S || state.conn == C_VERIFY_T)
77 		*bits_left = device->ov_left;
78 	else
79 		*bits_left = drbd_bm_total_weight(device) - device->rs_failed;
80 	/* >> 10 to prevent overflow,
81 	 * +1 to prevent division by zero */
82 	if (*bits_left > *rs_total) {
83 		/* D'oh. Maybe a logic bug somewhere.  More likely just a race
84 		 * between state change and reset of rs_total.
85 		 */
86 		*bits_left = *rs_total;
87 		*per_mil_done = *rs_total ? 0 : 1000;
88 	} else {
89 		/* Make sure the division happens in long context.
90 		 * We allow up to one petabyte storage right now,
91 		 * at a granularity of 4k per bit that is 2**38 bits.
92 		 * After shift right and multiplication by 1000,
93 		 * this should still fit easily into a 32bit long,
94 		 * so we don't need a 64bit division on 32bit arch.
95 		 * Note: currently we don't support such large bitmaps on 32bit
96 		 * arch anyways, but no harm done to be prepared for it here.
97 		 */
98 		unsigned int shift = *rs_total > UINT_MAX ? 16 : 10;
99 		unsigned long left = *bits_left >> shift;
100 		unsigned long total = 1UL + (*rs_total >> shift);
101 		unsigned long tmp = 1000UL - left * 1000UL/total;
102 		*per_mil_done = tmp;
103 	}
104 }
105 
106 
107 /*lge
108  * progress bars shamelessly adapted from driver/md/md.c
109  * output looks like
110  *	[=====>..............] 33.5% (23456/123456)
111  *	finish: 2:20:20 speed: 6,345 (6,456) K/sec
112  */
113 static void drbd_syncer_progress(struct drbd_device *device, struct seq_file *seq,
114 		union drbd_dev_state state)
115 {
116 	unsigned long db, dt, dbdt, rt, rs_total, rs_left;
117 	unsigned int res;
118 	int i, x, y;
119 	int stalled = 0;
120 
121 	drbd_get_syncer_progress(device, state, &rs_total, &rs_left, &res);
122 
123 	x = res/50;
124 	y = 20-x;
125 	seq_puts(seq, "\t[");
126 	for (i = 1; i < x; i++)
127 		seq_putc(seq, '=');
128 	seq_putc(seq, '>');
129 	for (i = 0; i < y; i++)
130 		seq_putc(seq, '.');
131 	seq_puts(seq, "] ");
132 
133 	if (state.conn == C_VERIFY_S || state.conn == C_VERIFY_T)
134 		seq_puts(seq, "verified:");
135 	else
136 		seq_puts(seq, "sync'ed:");
137 	seq_printf(seq, "%3u.%u%% ", res / 10, res % 10);
138 
139 	/* if more than a few GB, display in MB */
140 	if (rs_total > (4UL << (30 - BM_BLOCK_SHIFT)))
141 		seq_printf(seq, "(%lu/%lu)M",
142 			    (unsigned long) Bit2KB(rs_left >> 10),
143 			    (unsigned long) Bit2KB(rs_total >> 10));
144 	else
145 		seq_printf(seq, "(%lu/%lu)K",
146 			    (unsigned long) Bit2KB(rs_left),
147 			    (unsigned long) Bit2KB(rs_total));
148 
149 	seq_puts(seq, "\n\t");
150 
151 	/* see drivers/md/md.c
152 	 * We do not want to overflow, so the order of operands and
153 	 * the * 100 / 100 trick are important. We do a +1 to be
154 	 * safe against division by zero. We only estimate anyway.
155 	 *
156 	 * dt: time from mark until now
157 	 * db: blocks written from mark until now
158 	 * rt: remaining time
159 	 */
160 	/* Rolling marks. last_mark+1 may just now be modified.  last_mark+2 is
161 	 * at least (DRBD_SYNC_MARKS-2)*DRBD_SYNC_MARK_STEP old, and has at
162 	 * least DRBD_SYNC_MARK_STEP time before it will be modified. */
163 	/* ------------------------ ~18s average ------------------------ */
164 	i = (device->rs_last_mark + 2) % DRBD_SYNC_MARKS;
165 	dt = (jiffies - device->rs_mark_time[i]) / HZ;
166 	if (dt > 180)
167 		stalled = 1;
168 
169 	if (!dt)
170 		dt++;
171 	db = device->rs_mark_left[i] - rs_left;
172 	rt = (dt * (rs_left / (db/100+1)))/100; /* seconds */
173 
174 	seq_printf(seq, "finish: %lu:%02lu:%02lu",
175 		rt / 3600, (rt % 3600) / 60, rt % 60);
176 
177 	dbdt = Bit2KB(db/dt);
178 	seq_puts(seq, " speed: ");
179 	seq_printf_with_thousands_grouping(seq, dbdt);
180 	seq_puts(seq, " (");
181 	/* ------------------------- ~3s average ------------------------ */
182 	if (drbd_proc_details >= 1) {
183 		/* this is what drbd_rs_should_slow_down() uses */
184 		i = (device->rs_last_mark + DRBD_SYNC_MARKS-1) % DRBD_SYNC_MARKS;
185 		dt = (jiffies - device->rs_mark_time[i]) / HZ;
186 		if (!dt)
187 			dt++;
188 		db = device->rs_mark_left[i] - rs_left;
189 		dbdt = Bit2KB(db/dt);
190 		seq_printf_with_thousands_grouping(seq, dbdt);
191 		seq_puts(seq, " -- ");
192 	}
193 
194 	/* --------------------- long term average ---------------------- */
195 	/* mean speed since syncer started
196 	 * we do account for PausedSync periods */
197 	dt = (jiffies - device->rs_start - device->rs_paused) / HZ;
198 	if (dt == 0)
199 		dt = 1;
200 	db = rs_total - rs_left;
201 	dbdt = Bit2KB(db/dt);
202 	seq_printf_with_thousands_grouping(seq, dbdt);
203 	seq_putc(seq, ')');
204 
205 	if (state.conn == C_SYNC_TARGET ||
206 	    state.conn == C_VERIFY_S) {
207 		seq_puts(seq, " want: ");
208 		seq_printf_with_thousands_grouping(seq, device->c_sync_rate);
209 	}
210 	seq_printf(seq, " K/sec%s\n", stalled ? " (stalled)" : "");
211 
212 	if (drbd_proc_details >= 1) {
213 		/* 64 bit:
214 		 * we convert to sectors in the display below. */
215 		unsigned long bm_bits = drbd_bm_bits(device);
216 		unsigned long bit_pos;
217 		unsigned long long stop_sector = 0;
218 		if (state.conn == C_VERIFY_S ||
219 		    state.conn == C_VERIFY_T) {
220 			bit_pos = bm_bits - device->ov_left;
221 			if (verify_can_do_stop_sector(device))
222 				stop_sector = device->ov_stop_sector;
223 		} else
224 			bit_pos = device->bm_resync_fo;
225 		/* Total sectors may be slightly off for oddly
226 		 * sized devices. So what. */
227 		seq_printf(seq,
228 			"\t%3d%% sector pos: %llu/%llu",
229 			(int)(bit_pos / (bm_bits/100+1)),
230 			(unsigned long long)bit_pos * BM_SECT_PER_BIT,
231 			(unsigned long long)bm_bits * BM_SECT_PER_BIT);
232 		if (stop_sector != 0 && stop_sector != ULLONG_MAX)
233 			seq_printf(seq, " stop sector: %llu", stop_sector);
234 		seq_putc(seq, '\n');
235 	}
236 }
237 
238 static int drbd_seq_show(struct seq_file *seq, void *v)
239 {
240 	int i, prev_i = -1;
241 	const char *sn;
242 	struct drbd_device *device;
243 	struct net_conf *nc;
244 	union drbd_dev_state state;
245 	char wp;
246 
247 	static char write_ordering_chars[] = {
248 		[WO_NONE] = 'n',
249 		[WO_DRAIN_IO] = 'd',
250 		[WO_BDEV_FLUSH] = 'f',
251 	};
252 
253 	seq_printf(seq, "version: " REL_VERSION " (api:%d/proto:%d-%d)\n%s\n",
254 		   API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX, drbd_buildtag());
255 
256 	/*
257 	  cs .. connection state
258 	  ro .. node role (local/remote)
259 	  ds .. disk state (local/remote)
260 	     protocol
261 	     various flags
262 	  ns .. network send
263 	  nr .. network receive
264 	  dw .. disk write
265 	  dr .. disk read
266 	  al .. activity log write count
267 	  bm .. bitmap update write count
268 	  pe .. pending (waiting for ack or data reply)
269 	  ua .. unack'd (still need to send ack or data reply)
270 	  ap .. application requests accepted, but not yet completed
271 	  ep .. number of epochs currently "on the fly", P_BARRIER_ACK pending
272 	  wo .. write ordering mode currently in use
273 	 oos .. known out-of-sync kB
274 	*/
275 
276 	rcu_read_lock();
277 	idr_for_each_entry(&drbd_devices, device, i) {
278 		if (prev_i != i - 1)
279 			seq_putc(seq, '\n');
280 		prev_i = i;
281 
282 		state = device->state;
283 		sn = drbd_conn_str(state.conn);
284 
285 		if (state.conn == C_STANDALONE &&
286 		    state.disk == D_DISKLESS &&
287 		    state.role == R_SECONDARY) {
288 			seq_printf(seq, "%2d: cs:Unconfigured\n", i);
289 		} else {
290 			/* reset device->congestion_reason */
291 			bdi_rw_congested(device->rq_queue->backing_dev_info);
292 
293 			nc = rcu_dereference(first_peer_device(device)->connection->net_conf);
294 			wp = nc ? nc->wire_protocol - DRBD_PROT_A + 'A' : ' ';
295 			seq_printf(seq,
296 			   "%2d: cs:%s ro:%s/%s ds:%s/%s %c %c%c%c%c%c%c\n"
297 			   "    ns:%u nr:%u dw:%u dr:%u al:%u bm:%u "
298 			   "lo:%d pe:%d ua:%d ap:%d ep:%d wo:%c",
299 			   i, sn,
300 			   drbd_role_str(state.role),
301 			   drbd_role_str(state.peer),
302 			   drbd_disk_str(state.disk),
303 			   drbd_disk_str(state.pdsk),
304 			   wp,
305 			   drbd_suspended(device) ? 's' : 'r',
306 			   state.aftr_isp ? 'a' : '-',
307 			   state.peer_isp ? 'p' : '-',
308 			   state.user_isp ? 'u' : '-',
309 			   device->congestion_reason ?: '-',
310 			   test_bit(AL_SUSPENDED, &device->flags) ? 's' : '-',
311 			   device->send_cnt/2,
312 			   device->recv_cnt/2,
313 			   device->writ_cnt/2,
314 			   device->read_cnt/2,
315 			   device->al_writ_cnt,
316 			   device->bm_writ_cnt,
317 			   atomic_read(&device->local_cnt),
318 			   atomic_read(&device->ap_pending_cnt) +
319 			   atomic_read(&device->rs_pending_cnt),
320 			   atomic_read(&device->unacked_cnt),
321 			   atomic_read(&device->ap_bio_cnt),
322 			   first_peer_device(device)->connection->epochs,
323 			   write_ordering_chars[device->resource->write_ordering]
324 			);
325 			seq_printf(seq, " oos:%llu\n",
326 				   Bit2KB((unsigned long long)
327 					   drbd_bm_total_weight(device)));
328 		}
329 		if (state.conn == C_SYNC_SOURCE ||
330 		    state.conn == C_SYNC_TARGET ||
331 		    state.conn == C_VERIFY_S ||
332 		    state.conn == C_VERIFY_T)
333 			drbd_syncer_progress(device, seq, state);
334 
335 		if (drbd_proc_details >= 1 && get_ldev_if_state(device, D_FAILED)) {
336 			lc_seq_printf_stats(seq, device->resync);
337 			lc_seq_printf_stats(seq, device->act_log);
338 			put_ldev(device);
339 		}
340 
341 		if (drbd_proc_details >= 2)
342 			seq_printf(seq, "\tblocked on activity log: %d\n", atomic_read(&device->ap_actlog_cnt));
343 	}
344 	rcu_read_unlock();
345 
346 	return 0;
347 }
348 
349 static int drbd_proc_open(struct inode *inode, struct file *file)
350 {
351 	int err;
352 
353 	if (try_module_get(THIS_MODULE)) {
354 		err = single_open(file, drbd_seq_show, NULL);
355 		if (err)
356 			module_put(THIS_MODULE);
357 		return err;
358 	}
359 	return -ENODEV;
360 }
361 
362 static int drbd_proc_release(struct inode *inode, struct file *file)
363 {
364 	module_put(THIS_MODULE);
365 	return single_release(inode, file);
366 }
367 
368 /* PROC FS stuff end */
369