12db270a8SFrederic Weisbecker /* 22db270a8SFrederic Weisbecker * Copyright (C) 2006 Jens Axboe <axboe@kernel.dk> 32db270a8SFrederic Weisbecker * 42db270a8SFrederic Weisbecker * This program is free software; you can redistribute it and/or modify 52db270a8SFrederic Weisbecker * it under the terms of the GNU General Public License version 2 as 62db270a8SFrederic Weisbecker * published by the Free Software Foundation. 72db270a8SFrederic Weisbecker * 82db270a8SFrederic Weisbecker * This program is distributed in the hope that it will be useful, 92db270a8SFrederic Weisbecker * but WITHOUT ANY WARRANTY; without even the implied warranty of 102db270a8SFrederic Weisbecker * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 112db270a8SFrederic Weisbecker * GNU General Public License for more details. 122db270a8SFrederic Weisbecker * 132db270a8SFrederic Weisbecker * You should have received a copy of the GNU General Public License 142db270a8SFrederic Weisbecker * along with this program; if not, write to the Free Software 152db270a8SFrederic Weisbecker * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 162db270a8SFrederic Weisbecker * 172db270a8SFrederic Weisbecker */ 182db270a8SFrederic Weisbecker #include <linux/kernel.h> 192db270a8SFrederic Weisbecker #include <linux/blkdev.h> 202db270a8SFrederic Weisbecker #include <linux/blktrace_api.h> 212db270a8SFrederic Weisbecker #include <linux/percpu.h> 222db270a8SFrederic Weisbecker #include <linux/init.h> 232db270a8SFrederic Weisbecker #include <linux/mutex.h> 242db270a8SFrederic Weisbecker #include <linux/debugfs.h> 252db270a8SFrederic Weisbecker #include <linux/time.h> 262db270a8SFrederic Weisbecker #include <trace/block.h> 272db270a8SFrederic Weisbecker #include <linux/uaccess.h> 282db270a8SFrederic Weisbecker #include "trace_output.h" 292db270a8SFrederic Weisbecker 302db270a8SFrederic Weisbecker static unsigned int blktrace_seq __read_mostly = 1; 312db270a8SFrederic Weisbecker 322db270a8SFrederic Weisbecker static struct trace_array *blk_tr; 335006ea73SLi Zefan static bool blk_tracer_enabled __read_mostly; 342db270a8SFrederic Weisbecker 352db270a8SFrederic Weisbecker /* Select an alternative, minimalistic output than the original one */ 362db270a8SFrederic Weisbecker #define TRACE_BLK_OPT_CLASSIC 0x1 372db270a8SFrederic Weisbecker 382db270a8SFrederic Weisbecker static struct tracer_opt blk_tracer_opts[] = { 392db270a8SFrederic Weisbecker /* Default disable the minimalistic output */ 402db270a8SFrederic Weisbecker { TRACER_OPT(blk_classic, TRACE_BLK_OPT_CLASSIC) }, 412db270a8SFrederic Weisbecker { } 422db270a8SFrederic Weisbecker }; 432db270a8SFrederic Weisbecker 442db270a8SFrederic Weisbecker static struct tracer_flags blk_tracer_flags = { 452db270a8SFrederic Weisbecker .val = 0, 462db270a8SFrederic Weisbecker .opts = blk_tracer_opts, 472db270a8SFrederic Weisbecker }; 482db270a8SFrederic Weisbecker 492db270a8SFrederic Weisbecker /* Global reference count of probes */ 502db270a8SFrederic Weisbecker static atomic_t blk_probes_ref = ATOMIC_INIT(0); 512db270a8SFrederic Weisbecker 523c289ba7SLi Zefan static void blk_register_tracepoints(void); 532db270a8SFrederic Weisbecker static void blk_unregister_tracepoints(void); 542db270a8SFrederic Weisbecker 552db270a8SFrederic Weisbecker /* 562db270a8SFrederic Weisbecker * Send out a notify message. 572db270a8SFrederic Weisbecker */ 582db270a8SFrederic Weisbecker static void trace_note(struct blk_trace *bt, pid_t pid, int action, 592db270a8SFrederic Weisbecker const void *data, size_t len) 602db270a8SFrederic Weisbecker { 612db270a8SFrederic Weisbecker struct blk_io_trace *t; 622db270a8SFrederic Weisbecker 632db270a8SFrederic Weisbecker if (!bt->rchan) 642db270a8SFrederic Weisbecker return; 652db270a8SFrederic Weisbecker 662db270a8SFrederic Weisbecker t = relay_reserve(bt->rchan, sizeof(*t) + len); 672db270a8SFrederic Weisbecker if (t) { 682db270a8SFrederic Weisbecker const int cpu = smp_processor_id(); 692db270a8SFrederic Weisbecker 702db270a8SFrederic Weisbecker t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; 712db270a8SFrederic Weisbecker t->time = ktime_to_ns(ktime_get()); 722db270a8SFrederic Weisbecker t->device = bt->dev; 732db270a8SFrederic Weisbecker t->action = action; 742db270a8SFrederic Weisbecker t->pid = pid; 752db270a8SFrederic Weisbecker t->cpu = cpu; 762db270a8SFrederic Weisbecker t->pdu_len = len; 772db270a8SFrederic Weisbecker memcpy((void *) t + sizeof(*t), data, len); 782db270a8SFrederic Weisbecker } 792db270a8SFrederic Weisbecker } 802db270a8SFrederic Weisbecker 812db270a8SFrederic Weisbecker /* 822db270a8SFrederic Weisbecker * Send out a notify for this process, if we haven't done so since a trace 832db270a8SFrederic Weisbecker * started 842db270a8SFrederic Weisbecker */ 852db270a8SFrederic Weisbecker static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) 862db270a8SFrederic Weisbecker { 872db270a8SFrederic Weisbecker tsk->btrace_seq = blktrace_seq; 882db270a8SFrederic Weisbecker trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm)); 892db270a8SFrederic Weisbecker } 902db270a8SFrederic Weisbecker 912db270a8SFrederic Weisbecker static void trace_note_time(struct blk_trace *bt) 922db270a8SFrederic Weisbecker { 932db270a8SFrederic Weisbecker struct timespec now; 942db270a8SFrederic Weisbecker unsigned long flags; 952db270a8SFrederic Weisbecker u32 words[2]; 962db270a8SFrederic Weisbecker 972db270a8SFrederic Weisbecker getnstimeofday(&now); 982db270a8SFrederic Weisbecker words[0] = now.tv_sec; 992db270a8SFrederic Weisbecker words[1] = now.tv_nsec; 1002db270a8SFrederic Weisbecker 1012db270a8SFrederic Weisbecker local_irq_save(flags); 1022db270a8SFrederic Weisbecker trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words)); 1032db270a8SFrederic Weisbecker local_irq_restore(flags); 1042db270a8SFrederic Weisbecker } 1052db270a8SFrederic Weisbecker 1062db270a8SFrederic Weisbecker void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) 1072db270a8SFrederic Weisbecker { 1082db270a8SFrederic Weisbecker int n; 1092db270a8SFrederic Weisbecker va_list args; 1102db270a8SFrederic Weisbecker unsigned long flags; 1112db270a8SFrederic Weisbecker char *buf; 1122db270a8SFrederic Weisbecker 1132db270a8SFrederic Weisbecker if (blk_tr) { 1142db270a8SFrederic Weisbecker va_start(args, fmt); 1152db270a8SFrederic Weisbecker ftrace_vprintk(fmt, args); 1162db270a8SFrederic Weisbecker va_end(args); 1172db270a8SFrederic Weisbecker return; 1182db270a8SFrederic Weisbecker } 1192db270a8SFrederic Weisbecker 1202db270a8SFrederic Weisbecker if (!bt->msg_data) 1212db270a8SFrederic Weisbecker return; 1222db270a8SFrederic Weisbecker 1232db270a8SFrederic Weisbecker local_irq_save(flags); 1242db270a8SFrederic Weisbecker buf = per_cpu_ptr(bt->msg_data, smp_processor_id()); 1252db270a8SFrederic Weisbecker va_start(args, fmt); 1262db270a8SFrederic Weisbecker n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); 1272db270a8SFrederic Weisbecker va_end(args); 1282db270a8SFrederic Weisbecker 1292db270a8SFrederic Weisbecker trace_note(bt, 0, BLK_TN_MESSAGE, buf, n); 1302db270a8SFrederic Weisbecker local_irq_restore(flags); 1312db270a8SFrederic Weisbecker } 1322db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(__trace_note_message); 1332db270a8SFrederic Weisbecker 1342db270a8SFrederic Weisbecker static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, 1352db270a8SFrederic Weisbecker pid_t pid) 1362db270a8SFrederic Weisbecker { 1372db270a8SFrederic Weisbecker if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) 1382db270a8SFrederic Weisbecker return 1; 1392db270a8SFrederic Weisbecker if (sector < bt->start_lba || sector > bt->end_lba) 1402db270a8SFrederic Weisbecker return 1; 1412db270a8SFrederic Weisbecker if (bt->pid && pid != bt->pid) 1422db270a8SFrederic Weisbecker return 1; 1432db270a8SFrederic Weisbecker 1442db270a8SFrederic Weisbecker return 0; 1452db270a8SFrederic Weisbecker } 1462db270a8SFrederic Weisbecker 1472db270a8SFrederic Weisbecker /* 1482db270a8SFrederic Weisbecker * Data direction bit lookup 1492db270a8SFrederic Weisbecker */ 150e4955c99SLi Zefan static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ), 1512db270a8SFrederic Weisbecker BLK_TC_ACT(BLK_TC_WRITE) }; 1522db270a8SFrederic Weisbecker 1532db270a8SFrederic Weisbecker /* The ilog2() calls fall out because they're constant */ 1542db270a8SFrederic Weisbecker #define MASK_TC_BIT(rw, __name) ((rw & (1 << BIO_RW_ ## __name)) << \ 1552db270a8SFrederic Weisbecker (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - BIO_RW_ ## __name)) 1562db270a8SFrederic Weisbecker 1572db270a8SFrederic Weisbecker /* 1582db270a8SFrederic Weisbecker * The worker for the various blk_add_trace*() types. Fills out a 1592db270a8SFrederic Weisbecker * blk_io_trace structure and places it in a per-cpu subbuffer. 1602db270a8SFrederic Weisbecker */ 1612db270a8SFrederic Weisbecker static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, 1622db270a8SFrederic Weisbecker int rw, u32 what, int error, int pdu_len, void *pdu_data) 1632db270a8SFrederic Weisbecker { 1642db270a8SFrederic Weisbecker struct task_struct *tsk = current; 1652db270a8SFrederic Weisbecker struct ring_buffer_event *event = NULL; 1662db270a8SFrederic Weisbecker struct blk_io_trace *t; 1672db270a8SFrederic Weisbecker unsigned long flags = 0; 1682db270a8SFrederic Weisbecker unsigned long *sequence; 1692db270a8SFrederic Weisbecker pid_t pid; 1702db270a8SFrederic Weisbecker int cpu, pc = 0; 1712db270a8SFrederic Weisbecker 1722db270a8SFrederic Weisbecker if (unlikely(bt->trace_state != Blktrace_running || 1732db270a8SFrederic Weisbecker !blk_tracer_enabled)) 1742db270a8SFrederic Weisbecker return; 1752db270a8SFrederic Weisbecker 1762db270a8SFrederic Weisbecker what |= ddir_act[rw & WRITE]; 1772db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, BARRIER); 17872c26c9aSIngo Molnar what |= MASK_TC_BIT(rw, SYNCIO); 1792db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, AHEAD); 1802db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, META); 1812db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, DISCARD); 1822db270a8SFrederic Weisbecker 1832db270a8SFrederic Weisbecker pid = tsk->pid; 1842db270a8SFrederic Weisbecker if (unlikely(act_log_check(bt, what, sector, pid))) 1852db270a8SFrederic Weisbecker return; 1862db270a8SFrederic Weisbecker cpu = raw_smp_processor_id(); 1872db270a8SFrederic Weisbecker 1882db270a8SFrederic Weisbecker if (blk_tr) { 1892db270a8SFrederic Weisbecker tracing_record_cmdline(current); 1902db270a8SFrederic Weisbecker 1912db270a8SFrederic Weisbecker pc = preempt_count(); 1922db270a8SFrederic Weisbecker event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK, 1932db270a8SFrederic Weisbecker sizeof(*t) + pdu_len, 1942db270a8SFrederic Weisbecker 0, pc); 1952db270a8SFrederic Weisbecker if (!event) 1962db270a8SFrederic Weisbecker return; 1972db270a8SFrederic Weisbecker t = ring_buffer_event_data(event); 1982db270a8SFrederic Weisbecker goto record_it; 1992db270a8SFrederic Weisbecker } 2002db270a8SFrederic Weisbecker 2012db270a8SFrederic Weisbecker /* 2022db270a8SFrederic Weisbecker * A word about the locking here - we disable interrupts to reserve 2032db270a8SFrederic Weisbecker * some space in the relay per-cpu buffer, to prevent an irq 2042db270a8SFrederic Weisbecker * from coming in and stepping on our toes. 2052db270a8SFrederic Weisbecker */ 2062db270a8SFrederic Weisbecker local_irq_save(flags); 2072db270a8SFrederic Weisbecker 2082db270a8SFrederic Weisbecker if (unlikely(tsk->btrace_seq != blktrace_seq)) 2092db270a8SFrederic Weisbecker trace_note_tsk(bt, tsk); 2102db270a8SFrederic Weisbecker 2112db270a8SFrederic Weisbecker t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); 2122db270a8SFrederic Weisbecker if (t) { 2132db270a8SFrederic Weisbecker sequence = per_cpu_ptr(bt->sequence, cpu); 2142db270a8SFrederic Weisbecker 2152db270a8SFrederic Weisbecker t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; 2162db270a8SFrederic Weisbecker t->sequence = ++(*sequence); 2172db270a8SFrederic Weisbecker t->time = ktime_to_ns(ktime_get()); 2182db270a8SFrederic Weisbecker record_it: 2192db270a8SFrederic Weisbecker /* 2202db270a8SFrederic Weisbecker * These two are not needed in ftrace as they are in the 2212db270a8SFrederic Weisbecker * generic trace_entry, filled by tracing_generic_entry_update, 2222db270a8SFrederic Weisbecker * but for the trace_event->bin() synthesizer benefit we do it 2232db270a8SFrederic Weisbecker * here too. 2242db270a8SFrederic Weisbecker */ 2252db270a8SFrederic Weisbecker t->cpu = cpu; 2262db270a8SFrederic Weisbecker t->pid = pid; 2272db270a8SFrederic Weisbecker 2282db270a8SFrederic Weisbecker t->sector = sector; 2292db270a8SFrederic Weisbecker t->bytes = bytes; 2302db270a8SFrederic Weisbecker t->action = what; 2312db270a8SFrederic Weisbecker t->device = bt->dev; 2322db270a8SFrederic Weisbecker t->error = error; 2332db270a8SFrederic Weisbecker t->pdu_len = pdu_len; 2342db270a8SFrederic Weisbecker 2352db270a8SFrederic Weisbecker if (pdu_len) 2362db270a8SFrederic Weisbecker memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); 2372db270a8SFrederic Weisbecker 2382db270a8SFrederic Weisbecker if (blk_tr) { 2392db270a8SFrederic Weisbecker trace_buffer_unlock_commit(blk_tr, event, 0, pc); 2402db270a8SFrederic Weisbecker return; 2412db270a8SFrederic Weisbecker } 2422db270a8SFrederic Weisbecker } 2432db270a8SFrederic Weisbecker 2442db270a8SFrederic Weisbecker local_irq_restore(flags); 2452db270a8SFrederic Weisbecker } 2462db270a8SFrederic Weisbecker 2472db270a8SFrederic Weisbecker static struct dentry *blk_tree_root; 2482db270a8SFrederic Weisbecker static DEFINE_MUTEX(blk_tree_mutex); 2492db270a8SFrederic Weisbecker 2502db270a8SFrederic Weisbecker static void blk_trace_cleanup(struct blk_trace *bt) 2512db270a8SFrederic Weisbecker { 2522db270a8SFrederic Weisbecker debugfs_remove(bt->msg_file); 2532db270a8SFrederic Weisbecker debugfs_remove(bt->dropped_file); 2542db270a8SFrederic Weisbecker relay_close(bt->rchan); 2552db270a8SFrederic Weisbecker free_percpu(bt->sequence); 2562db270a8SFrederic Weisbecker free_percpu(bt->msg_data); 2572db270a8SFrederic Weisbecker kfree(bt); 2582db270a8SFrederic Weisbecker if (atomic_dec_and_test(&blk_probes_ref)) 2592db270a8SFrederic Weisbecker blk_unregister_tracepoints(); 2602db270a8SFrederic Weisbecker } 2612db270a8SFrederic Weisbecker 2622db270a8SFrederic Weisbecker int blk_trace_remove(struct request_queue *q) 2632db270a8SFrederic Weisbecker { 2642db270a8SFrederic Weisbecker struct blk_trace *bt; 2652db270a8SFrederic Weisbecker 2662db270a8SFrederic Weisbecker bt = xchg(&q->blk_trace, NULL); 2672db270a8SFrederic Weisbecker if (!bt) 2682db270a8SFrederic Weisbecker return -EINVAL; 2692db270a8SFrederic Weisbecker 2702db270a8SFrederic Weisbecker if (bt->trace_state == Blktrace_setup || 2712db270a8SFrederic Weisbecker bt->trace_state == Blktrace_stopped) 2722db270a8SFrederic Weisbecker blk_trace_cleanup(bt); 2732db270a8SFrederic Weisbecker 2742db270a8SFrederic Weisbecker return 0; 2752db270a8SFrederic Weisbecker } 2762db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_remove); 2772db270a8SFrederic Weisbecker 2782db270a8SFrederic Weisbecker static int blk_dropped_open(struct inode *inode, struct file *filp) 2792db270a8SFrederic Weisbecker { 2802db270a8SFrederic Weisbecker filp->private_data = inode->i_private; 2812db270a8SFrederic Weisbecker 2822db270a8SFrederic Weisbecker return 0; 2832db270a8SFrederic Weisbecker } 2842db270a8SFrederic Weisbecker 2852db270a8SFrederic Weisbecker static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, 2862db270a8SFrederic Weisbecker size_t count, loff_t *ppos) 2872db270a8SFrederic Weisbecker { 2882db270a8SFrederic Weisbecker struct blk_trace *bt = filp->private_data; 2892db270a8SFrederic Weisbecker char buf[16]; 2902db270a8SFrederic Weisbecker 2912db270a8SFrederic Weisbecker snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); 2922db270a8SFrederic Weisbecker 2932db270a8SFrederic Weisbecker return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); 2942db270a8SFrederic Weisbecker } 2952db270a8SFrederic Weisbecker 2962db270a8SFrederic Weisbecker static const struct file_operations blk_dropped_fops = { 2972db270a8SFrederic Weisbecker .owner = THIS_MODULE, 2982db270a8SFrederic Weisbecker .open = blk_dropped_open, 2992db270a8SFrederic Weisbecker .read = blk_dropped_read, 3002db270a8SFrederic Weisbecker }; 3012db270a8SFrederic Weisbecker 3022db270a8SFrederic Weisbecker static int blk_msg_open(struct inode *inode, struct file *filp) 3032db270a8SFrederic Weisbecker { 3042db270a8SFrederic Weisbecker filp->private_data = inode->i_private; 3052db270a8SFrederic Weisbecker 3062db270a8SFrederic Weisbecker return 0; 3072db270a8SFrederic Weisbecker } 3082db270a8SFrederic Weisbecker 3092db270a8SFrederic Weisbecker static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, 3102db270a8SFrederic Weisbecker size_t count, loff_t *ppos) 3112db270a8SFrederic Weisbecker { 3122db270a8SFrederic Weisbecker char *msg; 3132db270a8SFrederic Weisbecker struct blk_trace *bt; 3142db270a8SFrederic Weisbecker 3152db270a8SFrederic Weisbecker if (count > BLK_TN_MAX_MSG) 3162db270a8SFrederic Weisbecker return -EINVAL; 3172db270a8SFrederic Weisbecker 3182db270a8SFrederic Weisbecker msg = kmalloc(count, GFP_KERNEL); 3192db270a8SFrederic Weisbecker if (msg == NULL) 3202db270a8SFrederic Weisbecker return -ENOMEM; 3212db270a8SFrederic Weisbecker 3222db270a8SFrederic Weisbecker if (copy_from_user(msg, buffer, count)) { 3232db270a8SFrederic Weisbecker kfree(msg); 3242db270a8SFrederic Weisbecker return -EFAULT; 3252db270a8SFrederic Weisbecker } 3262db270a8SFrederic Weisbecker 3272db270a8SFrederic Weisbecker bt = filp->private_data; 3282db270a8SFrederic Weisbecker __trace_note_message(bt, "%s", msg); 3292db270a8SFrederic Weisbecker kfree(msg); 3302db270a8SFrederic Weisbecker 3312db270a8SFrederic Weisbecker return count; 3322db270a8SFrederic Weisbecker } 3332db270a8SFrederic Weisbecker 3342db270a8SFrederic Weisbecker static const struct file_operations blk_msg_fops = { 3352db270a8SFrederic Weisbecker .owner = THIS_MODULE, 3362db270a8SFrederic Weisbecker .open = blk_msg_open, 3372db270a8SFrederic Weisbecker .write = blk_msg_write, 3382db270a8SFrederic Weisbecker }; 3392db270a8SFrederic Weisbecker 3402db270a8SFrederic Weisbecker /* 3412db270a8SFrederic Weisbecker * Keep track of how many times we encountered a full subbuffer, to aid 3422db270a8SFrederic Weisbecker * the user space app in telling how many lost events there were. 3432db270a8SFrederic Weisbecker */ 3442db270a8SFrederic Weisbecker static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, 3452db270a8SFrederic Weisbecker void *prev_subbuf, size_t prev_padding) 3462db270a8SFrederic Weisbecker { 3472db270a8SFrederic Weisbecker struct blk_trace *bt; 3482db270a8SFrederic Weisbecker 3492db270a8SFrederic Weisbecker if (!relay_buf_full(buf)) 3502db270a8SFrederic Weisbecker return 1; 3512db270a8SFrederic Weisbecker 3522db270a8SFrederic Weisbecker bt = buf->chan->private_data; 3532db270a8SFrederic Weisbecker atomic_inc(&bt->dropped); 3542db270a8SFrederic Weisbecker return 0; 3552db270a8SFrederic Weisbecker } 3562db270a8SFrederic Weisbecker 3572db270a8SFrederic Weisbecker static int blk_remove_buf_file_callback(struct dentry *dentry) 3582db270a8SFrederic Weisbecker { 3592db270a8SFrederic Weisbecker struct dentry *parent = dentry->d_parent; 3602db270a8SFrederic Weisbecker debugfs_remove(dentry); 3612db270a8SFrederic Weisbecker 3622db270a8SFrederic Weisbecker /* 3632db270a8SFrederic Weisbecker * this will fail for all but the last file, but that is ok. what we 3642db270a8SFrederic Weisbecker * care about is the top level buts->name directory going away, when 3652db270a8SFrederic Weisbecker * the last trace file is gone. Then we don't have to rmdir() that 3662db270a8SFrederic Weisbecker * manually on trace stop, so it nicely solves the issue with 3672db270a8SFrederic Weisbecker * force killing of running traces. 3682db270a8SFrederic Weisbecker */ 3692db270a8SFrederic Weisbecker 3702db270a8SFrederic Weisbecker debugfs_remove(parent); 3712db270a8SFrederic Weisbecker return 0; 3722db270a8SFrederic Weisbecker } 3732db270a8SFrederic Weisbecker 3742db270a8SFrederic Weisbecker static struct dentry *blk_create_buf_file_callback(const char *filename, 3752db270a8SFrederic Weisbecker struct dentry *parent, 3762db270a8SFrederic Weisbecker int mode, 3772db270a8SFrederic Weisbecker struct rchan_buf *buf, 3782db270a8SFrederic Weisbecker int *is_global) 3792db270a8SFrederic Weisbecker { 3802db270a8SFrederic Weisbecker return debugfs_create_file(filename, mode, parent, buf, 3812db270a8SFrederic Weisbecker &relay_file_operations); 3822db270a8SFrederic Weisbecker } 3832db270a8SFrederic Weisbecker 3842db270a8SFrederic Weisbecker static struct rchan_callbacks blk_relay_callbacks = { 3852db270a8SFrederic Weisbecker .subbuf_start = blk_subbuf_start_callback, 3862db270a8SFrederic Weisbecker .create_buf_file = blk_create_buf_file_callback, 3872db270a8SFrederic Weisbecker .remove_buf_file = blk_remove_buf_file_callback, 3882db270a8SFrederic Weisbecker }; 3892db270a8SFrederic Weisbecker 3902db270a8SFrederic Weisbecker /* 3912db270a8SFrederic Weisbecker * Setup everything required to start tracing 3922db270a8SFrederic Weisbecker */ 3932db270a8SFrederic Weisbecker int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 3942db270a8SFrederic Weisbecker struct blk_user_trace_setup *buts) 3952db270a8SFrederic Weisbecker { 3962db270a8SFrederic Weisbecker struct blk_trace *old_bt, *bt = NULL; 3972db270a8SFrederic Weisbecker struct dentry *dir = NULL; 3982db270a8SFrederic Weisbecker int ret, i; 3992db270a8SFrederic Weisbecker 4002db270a8SFrederic Weisbecker if (!buts->buf_size || !buts->buf_nr) 4012db270a8SFrederic Weisbecker return -EINVAL; 4022db270a8SFrederic Weisbecker 4032db270a8SFrederic Weisbecker strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); 4042db270a8SFrederic Weisbecker buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; 4052db270a8SFrederic Weisbecker 4062db270a8SFrederic Weisbecker /* 4072db270a8SFrederic Weisbecker * some device names have larger paths - convert the slashes 4082db270a8SFrederic Weisbecker * to underscores for this to work as expected 4092db270a8SFrederic Weisbecker */ 4102db270a8SFrederic Weisbecker for (i = 0; i < strlen(buts->name); i++) 4112db270a8SFrederic Weisbecker if (buts->name[i] == '/') 4122db270a8SFrederic Weisbecker buts->name[i] = '_'; 4132db270a8SFrederic Weisbecker 4142db270a8SFrederic Weisbecker ret = -ENOMEM; 4152db270a8SFrederic Weisbecker bt = kzalloc(sizeof(*bt), GFP_KERNEL); 4162db270a8SFrederic Weisbecker if (!bt) 4172db270a8SFrederic Weisbecker goto err; 4182db270a8SFrederic Weisbecker 4192db270a8SFrederic Weisbecker bt->sequence = alloc_percpu(unsigned long); 4202db270a8SFrederic Weisbecker if (!bt->sequence) 4212db270a8SFrederic Weisbecker goto err; 4222db270a8SFrederic Weisbecker 423f0ef0398SIngo Molnar bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); 4242db270a8SFrederic Weisbecker if (!bt->msg_data) 4252db270a8SFrederic Weisbecker goto err; 4262db270a8SFrederic Weisbecker 4272db270a8SFrederic Weisbecker ret = -ENOENT; 4282db270a8SFrederic Weisbecker 4292db270a8SFrederic Weisbecker if (!blk_tree_root) { 4302db270a8SFrederic Weisbecker blk_tree_root = debugfs_create_dir("block", NULL); 4312db270a8SFrederic Weisbecker if (!blk_tree_root) 4321a17662eSLi Zefan goto err; 4332db270a8SFrederic Weisbecker } 4342db270a8SFrederic Weisbecker 4352db270a8SFrederic Weisbecker dir = debugfs_create_dir(buts->name, blk_tree_root); 4362db270a8SFrederic Weisbecker 4372db270a8SFrederic Weisbecker if (!dir) 4382db270a8SFrederic Weisbecker goto err; 4392db270a8SFrederic Weisbecker 4402db270a8SFrederic Weisbecker bt->dir = dir; 4412db270a8SFrederic Weisbecker bt->dev = dev; 4422db270a8SFrederic Weisbecker atomic_set(&bt->dropped, 0); 4432db270a8SFrederic Weisbecker 4442db270a8SFrederic Weisbecker ret = -EIO; 4452db270a8SFrederic Weisbecker bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, 4462db270a8SFrederic Weisbecker &blk_dropped_fops); 4472db270a8SFrederic Weisbecker if (!bt->dropped_file) 4482db270a8SFrederic Weisbecker goto err; 4492db270a8SFrederic Weisbecker 4502db270a8SFrederic Weisbecker bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); 4512db270a8SFrederic Weisbecker if (!bt->msg_file) 4522db270a8SFrederic Weisbecker goto err; 4532db270a8SFrederic Weisbecker 4542db270a8SFrederic Weisbecker bt->rchan = relay_open("trace", dir, buts->buf_size, 4552db270a8SFrederic Weisbecker buts->buf_nr, &blk_relay_callbacks, bt); 4562db270a8SFrederic Weisbecker if (!bt->rchan) 4572db270a8SFrederic Weisbecker goto err; 4582db270a8SFrederic Weisbecker 4592db270a8SFrederic Weisbecker bt->act_mask = buts->act_mask; 4602db270a8SFrederic Weisbecker if (!bt->act_mask) 4612db270a8SFrederic Weisbecker bt->act_mask = (u16) -1; 4622db270a8SFrederic Weisbecker 4632db270a8SFrederic Weisbecker bt->start_lba = buts->start_lba; 4642db270a8SFrederic Weisbecker bt->end_lba = buts->end_lba; 4652db270a8SFrederic Weisbecker if (!bt->end_lba) 4662db270a8SFrederic Weisbecker bt->end_lba = -1ULL; 4672db270a8SFrederic Weisbecker 4682db270a8SFrederic Weisbecker bt->pid = buts->pid; 4692db270a8SFrederic Weisbecker bt->trace_state = Blktrace_setup; 4702db270a8SFrederic Weisbecker 4712db270a8SFrederic Weisbecker ret = -EBUSY; 4722db270a8SFrederic Weisbecker old_bt = xchg(&q->blk_trace, bt); 4732db270a8SFrederic Weisbecker if (old_bt) { 4742db270a8SFrederic Weisbecker (void) xchg(&q->blk_trace, old_bt); 4752db270a8SFrederic Weisbecker goto err; 4762db270a8SFrederic Weisbecker } 4772db270a8SFrederic Weisbecker 478cbe28296SLi Zefan if (atomic_add_return(1, &blk_probes_ref) == 1) 479cbe28296SLi Zefan blk_register_tracepoints(); 480cbe28296SLi Zefan 4812db270a8SFrederic Weisbecker return 0; 4822db270a8SFrederic Weisbecker err: 4832db270a8SFrederic Weisbecker if (bt) { 4842db270a8SFrederic Weisbecker if (bt->msg_file) 4852db270a8SFrederic Weisbecker debugfs_remove(bt->msg_file); 4862db270a8SFrederic Weisbecker if (bt->dropped_file) 4872db270a8SFrederic Weisbecker debugfs_remove(bt->dropped_file); 4882db270a8SFrederic Weisbecker free_percpu(bt->sequence); 4892db270a8SFrederic Weisbecker free_percpu(bt->msg_data); 4902db270a8SFrederic Weisbecker if (bt->rchan) 4912db270a8SFrederic Weisbecker relay_close(bt->rchan); 4922db270a8SFrederic Weisbecker kfree(bt); 4932db270a8SFrederic Weisbecker } 4942db270a8SFrederic Weisbecker return ret; 4952db270a8SFrederic Weisbecker } 4962db270a8SFrederic Weisbecker 4972db270a8SFrederic Weisbecker int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 4982db270a8SFrederic Weisbecker char __user *arg) 4992db270a8SFrederic Weisbecker { 5002db270a8SFrederic Weisbecker struct blk_user_trace_setup buts; 5012db270a8SFrederic Weisbecker int ret; 5022db270a8SFrederic Weisbecker 5032db270a8SFrederic Weisbecker ret = copy_from_user(&buts, arg, sizeof(buts)); 5042db270a8SFrederic Weisbecker if (ret) 5052db270a8SFrederic Weisbecker return -EFAULT; 5062db270a8SFrederic Weisbecker 5072db270a8SFrederic Weisbecker ret = do_blk_trace_setup(q, name, dev, &buts); 5082db270a8SFrederic Weisbecker if (ret) 5092db270a8SFrederic Weisbecker return ret; 5102db270a8SFrederic Weisbecker 5112db270a8SFrederic Weisbecker if (copy_to_user(arg, &buts, sizeof(buts))) 5122db270a8SFrederic Weisbecker return -EFAULT; 5132db270a8SFrederic Weisbecker 5142db270a8SFrederic Weisbecker return 0; 5152db270a8SFrederic Weisbecker } 5162db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_setup); 5172db270a8SFrederic Weisbecker 5182db270a8SFrederic Weisbecker int blk_trace_startstop(struct request_queue *q, int start) 5192db270a8SFrederic Weisbecker { 5202db270a8SFrederic Weisbecker int ret; 5212db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 5222db270a8SFrederic Weisbecker 5232db270a8SFrederic Weisbecker if (bt == NULL) 5242db270a8SFrederic Weisbecker return -EINVAL; 5252db270a8SFrederic Weisbecker 5262db270a8SFrederic Weisbecker /* 5272db270a8SFrederic Weisbecker * For starting a trace, we can transition from a setup or stopped 5282db270a8SFrederic Weisbecker * trace. For stopping a trace, the state must be running 5292db270a8SFrederic Weisbecker */ 5302db270a8SFrederic Weisbecker ret = -EINVAL; 5312db270a8SFrederic Weisbecker if (start) { 5322db270a8SFrederic Weisbecker if (bt->trace_state == Blktrace_setup || 5332db270a8SFrederic Weisbecker bt->trace_state == Blktrace_stopped) { 5342db270a8SFrederic Weisbecker blktrace_seq++; 5352db270a8SFrederic Weisbecker smp_mb(); 5362db270a8SFrederic Weisbecker bt->trace_state = Blktrace_running; 5372db270a8SFrederic Weisbecker 5382db270a8SFrederic Weisbecker trace_note_time(bt); 5392db270a8SFrederic Weisbecker ret = 0; 5402db270a8SFrederic Weisbecker } 5412db270a8SFrederic Weisbecker } else { 5422db270a8SFrederic Weisbecker if (bt->trace_state == Blktrace_running) { 5432db270a8SFrederic Weisbecker bt->trace_state = Blktrace_stopped; 5442db270a8SFrederic Weisbecker relay_flush(bt->rchan); 5452db270a8SFrederic Weisbecker ret = 0; 5462db270a8SFrederic Weisbecker } 5472db270a8SFrederic Weisbecker } 5482db270a8SFrederic Weisbecker 5492db270a8SFrederic Weisbecker return ret; 5502db270a8SFrederic Weisbecker } 5512db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_startstop); 5522db270a8SFrederic Weisbecker 5532db270a8SFrederic Weisbecker /** 5542db270a8SFrederic Weisbecker * blk_trace_ioctl: - handle the ioctls associated with tracing 5552db270a8SFrederic Weisbecker * @bdev: the block device 5562db270a8SFrederic Weisbecker * @cmd: the ioctl cmd 5572db270a8SFrederic Weisbecker * @arg: the argument data, if any 5582db270a8SFrederic Weisbecker * 5592db270a8SFrederic Weisbecker **/ 5602db270a8SFrederic Weisbecker int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) 5612db270a8SFrederic Weisbecker { 5622db270a8SFrederic Weisbecker struct request_queue *q; 5632db270a8SFrederic Weisbecker int ret, start = 0; 5642db270a8SFrederic Weisbecker char b[BDEVNAME_SIZE]; 5652db270a8SFrederic Weisbecker 5662db270a8SFrederic Weisbecker q = bdev_get_queue(bdev); 5672db270a8SFrederic Weisbecker if (!q) 5682db270a8SFrederic Weisbecker return -ENXIO; 5692db270a8SFrederic Weisbecker 5702db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 5712db270a8SFrederic Weisbecker 5722db270a8SFrederic Weisbecker switch (cmd) { 5732db270a8SFrederic Weisbecker case BLKTRACESETUP: 5742db270a8SFrederic Weisbecker bdevname(bdev, b); 5752db270a8SFrederic Weisbecker ret = blk_trace_setup(q, b, bdev->bd_dev, arg); 5762db270a8SFrederic Weisbecker break; 5772db270a8SFrederic Weisbecker case BLKTRACESTART: 5782db270a8SFrederic Weisbecker start = 1; 5792db270a8SFrederic Weisbecker case BLKTRACESTOP: 5802db270a8SFrederic Weisbecker ret = blk_trace_startstop(q, start); 5812db270a8SFrederic Weisbecker break; 5822db270a8SFrederic Weisbecker case BLKTRACETEARDOWN: 5832db270a8SFrederic Weisbecker ret = blk_trace_remove(q); 5842db270a8SFrederic Weisbecker break; 5852db270a8SFrederic Weisbecker default: 5862db270a8SFrederic Weisbecker ret = -ENOTTY; 5872db270a8SFrederic Weisbecker break; 5882db270a8SFrederic Weisbecker } 5892db270a8SFrederic Weisbecker 5902db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 5912db270a8SFrederic Weisbecker return ret; 5922db270a8SFrederic Weisbecker } 5932db270a8SFrederic Weisbecker 5942db270a8SFrederic Weisbecker /** 5952db270a8SFrederic Weisbecker * blk_trace_shutdown: - stop and cleanup trace structures 5962db270a8SFrederic Weisbecker * @q: the request queue associated with the device 5972db270a8SFrederic Weisbecker * 5982db270a8SFrederic Weisbecker **/ 5992db270a8SFrederic Weisbecker void blk_trace_shutdown(struct request_queue *q) 6002db270a8SFrederic Weisbecker { 6012db270a8SFrederic Weisbecker if (q->blk_trace) { 6022db270a8SFrederic Weisbecker blk_trace_startstop(q, 0); 6032db270a8SFrederic Weisbecker blk_trace_remove(q); 6042db270a8SFrederic Weisbecker } 6052db270a8SFrederic Weisbecker } 6062db270a8SFrederic Weisbecker 6072db270a8SFrederic Weisbecker /* 6082db270a8SFrederic Weisbecker * blktrace probes 6092db270a8SFrederic Weisbecker */ 6102db270a8SFrederic Weisbecker 6112db270a8SFrederic Weisbecker /** 6122db270a8SFrederic Weisbecker * blk_add_trace_rq - Add a trace for a request oriented action 6132db270a8SFrederic Weisbecker * @q: queue the io is for 6142db270a8SFrederic Weisbecker * @rq: the source request 6152db270a8SFrederic Weisbecker * @what: the action 6162db270a8SFrederic Weisbecker * 6172db270a8SFrederic Weisbecker * Description: 6182db270a8SFrederic Weisbecker * Records an action against a request. Will log the bio offset + size. 6192db270a8SFrederic Weisbecker * 6202db270a8SFrederic Weisbecker **/ 6212db270a8SFrederic Weisbecker static void blk_add_trace_rq(struct request_queue *q, struct request *rq, 6222db270a8SFrederic Weisbecker u32 what) 6232db270a8SFrederic Weisbecker { 6242db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 6252db270a8SFrederic Weisbecker int rw = rq->cmd_flags & 0x03; 6262db270a8SFrederic Weisbecker 6272db270a8SFrederic Weisbecker if (likely(!bt)) 6282db270a8SFrederic Weisbecker return; 6292db270a8SFrederic Weisbecker 6302db270a8SFrederic Weisbecker if (blk_discard_rq(rq)) 6312db270a8SFrederic Weisbecker rw |= (1 << BIO_RW_DISCARD); 6322db270a8SFrederic Weisbecker 6332db270a8SFrederic Weisbecker if (blk_pc_request(rq)) { 6342db270a8SFrederic Weisbecker what |= BLK_TC_ACT(BLK_TC_PC); 6352db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, 6362db270a8SFrederic Weisbecker sizeof(rq->cmd), rq->cmd); 6372db270a8SFrederic Weisbecker } else { 6382db270a8SFrederic Weisbecker what |= BLK_TC_ACT(BLK_TC_FS); 6392db270a8SFrederic Weisbecker __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, 6402db270a8SFrederic Weisbecker rw, what, rq->errors, 0, NULL); 6412db270a8SFrederic Weisbecker } 6422db270a8SFrederic Weisbecker } 6432db270a8SFrederic Weisbecker 6442db270a8SFrederic Weisbecker static void blk_add_trace_rq_abort(struct request_queue *q, struct request *rq) 6452db270a8SFrederic Weisbecker { 6462db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_ABORT); 6472db270a8SFrederic Weisbecker } 6482db270a8SFrederic Weisbecker 6492db270a8SFrederic Weisbecker static void blk_add_trace_rq_insert(struct request_queue *q, struct request *rq) 6502db270a8SFrederic Weisbecker { 6512db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_INSERT); 6522db270a8SFrederic Weisbecker } 6532db270a8SFrederic Weisbecker 6542db270a8SFrederic Weisbecker static void blk_add_trace_rq_issue(struct request_queue *q, struct request *rq) 6552db270a8SFrederic Weisbecker { 6562db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_ISSUE); 6572db270a8SFrederic Weisbecker } 6582db270a8SFrederic Weisbecker 6592db270a8SFrederic Weisbecker static void blk_add_trace_rq_requeue(struct request_queue *q, 6602db270a8SFrederic Weisbecker struct request *rq) 6612db270a8SFrederic Weisbecker { 6622db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); 6632db270a8SFrederic Weisbecker } 6642db270a8SFrederic Weisbecker 6652db270a8SFrederic Weisbecker static void blk_add_trace_rq_complete(struct request_queue *q, 6662db270a8SFrederic Weisbecker struct request *rq) 6672db270a8SFrederic Weisbecker { 6682db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); 6692db270a8SFrederic Weisbecker } 6702db270a8SFrederic Weisbecker 6712db270a8SFrederic Weisbecker /** 6722db270a8SFrederic Weisbecker * blk_add_trace_bio - Add a trace for a bio oriented action 6732db270a8SFrederic Weisbecker * @q: queue the io is for 6742db270a8SFrederic Weisbecker * @bio: the source bio 6752db270a8SFrederic Weisbecker * @what: the action 6762db270a8SFrederic Weisbecker * 6772db270a8SFrederic Weisbecker * Description: 6782db270a8SFrederic Weisbecker * Records an action against a bio. Will log the bio offset + size. 6792db270a8SFrederic Weisbecker * 6802db270a8SFrederic Weisbecker **/ 6812db270a8SFrederic Weisbecker static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, 6822db270a8SFrederic Weisbecker u32 what) 6832db270a8SFrederic Weisbecker { 6842db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 6852db270a8SFrederic Weisbecker 6862db270a8SFrederic Weisbecker if (likely(!bt)) 6872db270a8SFrederic Weisbecker return; 6882db270a8SFrederic Weisbecker 6892db270a8SFrederic Weisbecker __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, 6902db270a8SFrederic Weisbecker !bio_flagged(bio, BIO_UPTODATE), 0, NULL); 6912db270a8SFrederic Weisbecker } 6922db270a8SFrederic Weisbecker 6932db270a8SFrederic Weisbecker static void blk_add_trace_bio_bounce(struct request_queue *q, struct bio *bio) 6942db270a8SFrederic Weisbecker { 6952db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); 6962db270a8SFrederic Weisbecker } 6972db270a8SFrederic Weisbecker 6982db270a8SFrederic Weisbecker static void blk_add_trace_bio_complete(struct request_queue *q, struct bio *bio) 6992db270a8SFrederic Weisbecker { 7002db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); 7012db270a8SFrederic Weisbecker } 7022db270a8SFrederic Weisbecker 7032db270a8SFrederic Weisbecker static void blk_add_trace_bio_backmerge(struct request_queue *q, 7042db270a8SFrederic Weisbecker struct bio *bio) 7052db270a8SFrederic Weisbecker { 7062db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); 7072db270a8SFrederic Weisbecker } 7082db270a8SFrederic Weisbecker 7092db270a8SFrederic Weisbecker static void blk_add_trace_bio_frontmerge(struct request_queue *q, 7102db270a8SFrederic Weisbecker struct bio *bio) 7112db270a8SFrederic Weisbecker { 7122db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); 7132db270a8SFrederic Weisbecker } 7142db270a8SFrederic Weisbecker 7152db270a8SFrederic Weisbecker static void blk_add_trace_bio_queue(struct request_queue *q, struct bio *bio) 7162db270a8SFrederic Weisbecker { 7172db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_QUEUE); 7182db270a8SFrederic Weisbecker } 7192db270a8SFrederic Weisbecker 7202db270a8SFrederic Weisbecker static void blk_add_trace_getrq(struct request_queue *q, 7212db270a8SFrederic Weisbecker struct bio *bio, int rw) 7222db270a8SFrederic Weisbecker { 7232db270a8SFrederic Weisbecker if (bio) 7242db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_GETRQ); 7252db270a8SFrederic Weisbecker else { 7262db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7272db270a8SFrederic Weisbecker 7282db270a8SFrederic Weisbecker if (bt) 7292db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); 7302db270a8SFrederic Weisbecker } 7312db270a8SFrederic Weisbecker } 7322db270a8SFrederic Weisbecker 7332db270a8SFrederic Weisbecker 7342db270a8SFrederic Weisbecker static void blk_add_trace_sleeprq(struct request_queue *q, 7352db270a8SFrederic Weisbecker struct bio *bio, int rw) 7362db270a8SFrederic Weisbecker { 7372db270a8SFrederic Weisbecker if (bio) 7382db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); 7392db270a8SFrederic Weisbecker else { 7402db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7412db270a8SFrederic Weisbecker 7422db270a8SFrederic Weisbecker if (bt) 7432db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, 7442db270a8SFrederic Weisbecker 0, 0, NULL); 7452db270a8SFrederic Weisbecker } 7462db270a8SFrederic Weisbecker } 7472db270a8SFrederic Weisbecker 7482db270a8SFrederic Weisbecker static void blk_add_trace_plug(struct request_queue *q) 7492db270a8SFrederic Weisbecker { 7502db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7512db270a8SFrederic Weisbecker 7522db270a8SFrederic Weisbecker if (bt) 7532db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); 7542db270a8SFrederic Weisbecker } 7552db270a8SFrederic Weisbecker 7562db270a8SFrederic Weisbecker static void blk_add_trace_unplug_io(struct request_queue *q) 7572db270a8SFrederic Weisbecker { 7582db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7592db270a8SFrederic Weisbecker 7602db270a8SFrederic Weisbecker if (bt) { 7612db270a8SFrederic Weisbecker unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; 7622db270a8SFrederic Weisbecker __be64 rpdu = cpu_to_be64(pdu); 7632db270a8SFrederic Weisbecker 7642db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, 7652db270a8SFrederic Weisbecker sizeof(rpdu), &rpdu); 7662db270a8SFrederic Weisbecker } 7672db270a8SFrederic Weisbecker } 7682db270a8SFrederic Weisbecker 7692db270a8SFrederic Weisbecker static void blk_add_trace_unplug_timer(struct request_queue *q) 7702db270a8SFrederic Weisbecker { 7712db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7722db270a8SFrederic Weisbecker 7732db270a8SFrederic Weisbecker if (bt) { 7742db270a8SFrederic Weisbecker unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; 7752db270a8SFrederic Weisbecker __be64 rpdu = cpu_to_be64(pdu); 7762db270a8SFrederic Weisbecker 7772db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, 7782db270a8SFrederic Weisbecker sizeof(rpdu), &rpdu); 7792db270a8SFrederic Weisbecker } 7802db270a8SFrederic Weisbecker } 7812db270a8SFrederic Weisbecker 7822db270a8SFrederic Weisbecker static void blk_add_trace_split(struct request_queue *q, struct bio *bio, 7832db270a8SFrederic Weisbecker unsigned int pdu) 7842db270a8SFrederic Weisbecker { 7852db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7862db270a8SFrederic Weisbecker 7872db270a8SFrederic Weisbecker if (bt) { 7882db270a8SFrederic Weisbecker __be64 rpdu = cpu_to_be64(pdu); 7892db270a8SFrederic Weisbecker 7902db270a8SFrederic Weisbecker __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, 7912db270a8SFrederic Weisbecker BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), 7922db270a8SFrederic Weisbecker sizeof(rpdu), &rpdu); 7932db270a8SFrederic Weisbecker } 7942db270a8SFrederic Weisbecker } 7952db270a8SFrederic Weisbecker 7962db270a8SFrederic Weisbecker /** 7972db270a8SFrederic Weisbecker * blk_add_trace_remap - Add a trace for a remap operation 7982db270a8SFrederic Weisbecker * @q: queue the io is for 7992db270a8SFrederic Weisbecker * @bio: the source bio 8002db270a8SFrederic Weisbecker * @dev: target device 8012db270a8SFrederic Weisbecker * @from: source sector 8022db270a8SFrederic Weisbecker * @to: target sector 8032db270a8SFrederic Weisbecker * 8042db270a8SFrederic Weisbecker * Description: 8052db270a8SFrederic Weisbecker * Device mapper or raid target sometimes need to split a bio because 8062db270a8SFrederic Weisbecker * it spans a stripe (or similar). Add a trace for that action. 8072db270a8SFrederic Weisbecker * 8082db270a8SFrederic Weisbecker **/ 8092db270a8SFrederic Weisbecker static void blk_add_trace_remap(struct request_queue *q, struct bio *bio, 8102db270a8SFrederic Weisbecker dev_t dev, sector_t from, sector_t to) 8112db270a8SFrederic Weisbecker { 8122db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8132db270a8SFrederic Weisbecker struct blk_io_trace_remap r; 8142db270a8SFrederic Weisbecker 8152db270a8SFrederic Weisbecker if (likely(!bt)) 8162db270a8SFrederic Weisbecker return; 8172db270a8SFrederic Weisbecker 8182db270a8SFrederic Weisbecker r.device = cpu_to_be32(dev); 8192db270a8SFrederic Weisbecker r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev); 8202db270a8SFrederic Weisbecker r.sector = cpu_to_be64(to); 8212db270a8SFrederic Weisbecker 8222db270a8SFrederic Weisbecker __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, 8232db270a8SFrederic Weisbecker !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); 8242db270a8SFrederic Weisbecker } 8252db270a8SFrederic Weisbecker 8262db270a8SFrederic Weisbecker /** 8272db270a8SFrederic Weisbecker * blk_add_driver_data - Add binary message with driver-specific data 8282db270a8SFrederic Weisbecker * @q: queue the io is for 8292db270a8SFrederic Weisbecker * @rq: io request 8302db270a8SFrederic Weisbecker * @data: driver-specific data 8312db270a8SFrederic Weisbecker * @len: length of driver-specific data 8322db270a8SFrederic Weisbecker * 8332db270a8SFrederic Weisbecker * Description: 8342db270a8SFrederic Weisbecker * Some drivers might want to write driver-specific data per request. 8352db270a8SFrederic Weisbecker * 8362db270a8SFrederic Weisbecker **/ 8372db270a8SFrederic Weisbecker void blk_add_driver_data(struct request_queue *q, 8382db270a8SFrederic Weisbecker struct request *rq, 8392db270a8SFrederic Weisbecker void *data, size_t len) 8402db270a8SFrederic Weisbecker { 8412db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8422db270a8SFrederic Weisbecker 8432db270a8SFrederic Weisbecker if (likely(!bt)) 8442db270a8SFrederic Weisbecker return; 8452db270a8SFrederic Weisbecker 8462db270a8SFrederic Weisbecker if (blk_pc_request(rq)) 8472db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, rq->data_len, 0, BLK_TA_DRV_DATA, 8482db270a8SFrederic Weisbecker rq->errors, len, data); 8492db270a8SFrederic Weisbecker else 8502db270a8SFrederic Weisbecker __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, 8512db270a8SFrederic Weisbecker 0, BLK_TA_DRV_DATA, rq->errors, len, data); 8522db270a8SFrederic Weisbecker } 8532db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_add_driver_data); 8542db270a8SFrederic Weisbecker 8553c289ba7SLi Zefan static void blk_register_tracepoints(void) 8562db270a8SFrederic Weisbecker { 8572db270a8SFrederic Weisbecker int ret; 8582db270a8SFrederic Weisbecker 8592db270a8SFrederic Weisbecker ret = register_trace_block_rq_abort(blk_add_trace_rq_abort); 8602db270a8SFrederic Weisbecker WARN_ON(ret); 8612db270a8SFrederic Weisbecker ret = register_trace_block_rq_insert(blk_add_trace_rq_insert); 8622db270a8SFrederic Weisbecker WARN_ON(ret); 8632db270a8SFrederic Weisbecker ret = register_trace_block_rq_issue(blk_add_trace_rq_issue); 8642db270a8SFrederic Weisbecker WARN_ON(ret); 8652db270a8SFrederic Weisbecker ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue); 8662db270a8SFrederic Weisbecker WARN_ON(ret); 8672db270a8SFrederic Weisbecker ret = register_trace_block_rq_complete(blk_add_trace_rq_complete); 8682db270a8SFrederic Weisbecker WARN_ON(ret); 8692db270a8SFrederic Weisbecker ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce); 8702db270a8SFrederic Weisbecker WARN_ON(ret); 8712db270a8SFrederic Weisbecker ret = register_trace_block_bio_complete(blk_add_trace_bio_complete); 8722db270a8SFrederic Weisbecker WARN_ON(ret); 8732db270a8SFrederic Weisbecker ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); 8742db270a8SFrederic Weisbecker WARN_ON(ret); 8752db270a8SFrederic Weisbecker ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); 8762db270a8SFrederic Weisbecker WARN_ON(ret); 8772db270a8SFrederic Weisbecker ret = register_trace_block_bio_queue(blk_add_trace_bio_queue); 8782db270a8SFrederic Weisbecker WARN_ON(ret); 8792db270a8SFrederic Weisbecker ret = register_trace_block_getrq(blk_add_trace_getrq); 8802db270a8SFrederic Weisbecker WARN_ON(ret); 8812db270a8SFrederic Weisbecker ret = register_trace_block_sleeprq(blk_add_trace_sleeprq); 8822db270a8SFrederic Weisbecker WARN_ON(ret); 8832db270a8SFrederic Weisbecker ret = register_trace_block_plug(blk_add_trace_plug); 8842db270a8SFrederic Weisbecker WARN_ON(ret); 8852db270a8SFrederic Weisbecker ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer); 8862db270a8SFrederic Weisbecker WARN_ON(ret); 8872db270a8SFrederic Weisbecker ret = register_trace_block_unplug_io(blk_add_trace_unplug_io); 8882db270a8SFrederic Weisbecker WARN_ON(ret); 8892db270a8SFrederic Weisbecker ret = register_trace_block_split(blk_add_trace_split); 8902db270a8SFrederic Weisbecker WARN_ON(ret); 8912db270a8SFrederic Weisbecker ret = register_trace_block_remap(blk_add_trace_remap); 8922db270a8SFrederic Weisbecker WARN_ON(ret); 8932db270a8SFrederic Weisbecker } 8942db270a8SFrederic Weisbecker 8952db270a8SFrederic Weisbecker static void blk_unregister_tracepoints(void) 8962db270a8SFrederic Weisbecker { 8972db270a8SFrederic Weisbecker unregister_trace_block_remap(blk_add_trace_remap); 8982db270a8SFrederic Weisbecker unregister_trace_block_split(blk_add_trace_split); 8992db270a8SFrederic Weisbecker unregister_trace_block_unplug_io(blk_add_trace_unplug_io); 9002db270a8SFrederic Weisbecker unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer); 9012db270a8SFrederic Weisbecker unregister_trace_block_plug(blk_add_trace_plug); 9022db270a8SFrederic Weisbecker unregister_trace_block_sleeprq(blk_add_trace_sleeprq); 9032db270a8SFrederic Weisbecker unregister_trace_block_getrq(blk_add_trace_getrq); 9042db270a8SFrederic Weisbecker unregister_trace_block_bio_queue(blk_add_trace_bio_queue); 9052db270a8SFrederic Weisbecker unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); 9062db270a8SFrederic Weisbecker unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); 9072db270a8SFrederic Weisbecker unregister_trace_block_bio_complete(blk_add_trace_bio_complete); 9082db270a8SFrederic Weisbecker unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce); 9092db270a8SFrederic Weisbecker unregister_trace_block_rq_complete(blk_add_trace_rq_complete); 9102db270a8SFrederic Weisbecker unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue); 9112db270a8SFrederic Weisbecker unregister_trace_block_rq_issue(blk_add_trace_rq_issue); 9122db270a8SFrederic Weisbecker unregister_trace_block_rq_insert(blk_add_trace_rq_insert); 9132db270a8SFrederic Weisbecker unregister_trace_block_rq_abort(blk_add_trace_rq_abort); 9142db270a8SFrederic Weisbecker 9152db270a8SFrederic Weisbecker tracepoint_synchronize_unregister(); 9162db270a8SFrederic Weisbecker } 9172db270a8SFrederic Weisbecker 9182db270a8SFrederic Weisbecker /* 9192db270a8SFrederic Weisbecker * struct blk_io_tracer formatting routines 9202db270a8SFrederic Weisbecker */ 9212db270a8SFrederic Weisbecker 9222db270a8SFrederic Weisbecker static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) 9232db270a8SFrederic Weisbecker { 9242db270a8SFrederic Weisbecker int i = 0; 92565796348SLi Zefan int tc = t->action >> BLK_TC_SHIFT; 9262db270a8SFrederic Weisbecker 92765796348SLi Zefan if (tc & BLK_TC_DISCARD) 9282db270a8SFrederic Weisbecker rwbs[i++] = 'D'; 92965796348SLi Zefan else if (tc & BLK_TC_WRITE) 9302db270a8SFrederic Weisbecker rwbs[i++] = 'W'; 9312db270a8SFrederic Weisbecker else if (t->bytes) 9322db270a8SFrederic Weisbecker rwbs[i++] = 'R'; 9332db270a8SFrederic Weisbecker else 9342db270a8SFrederic Weisbecker rwbs[i++] = 'N'; 9352db270a8SFrederic Weisbecker 93665796348SLi Zefan if (tc & BLK_TC_AHEAD) 9372db270a8SFrederic Weisbecker rwbs[i++] = 'A'; 93865796348SLi Zefan if (tc & BLK_TC_BARRIER) 9392db270a8SFrederic Weisbecker rwbs[i++] = 'B'; 94065796348SLi Zefan if (tc & BLK_TC_SYNC) 9412db270a8SFrederic Weisbecker rwbs[i++] = 'S'; 94265796348SLi Zefan if (tc & BLK_TC_META) 9432db270a8SFrederic Weisbecker rwbs[i++] = 'M'; 9442db270a8SFrederic Weisbecker 9452db270a8SFrederic Weisbecker rwbs[i] = '\0'; 9462db270a8SFrederic Weisbecker } 9472db270a8SFrederic Weisbecker 9482db270a8SFrederic Weisbecker static inline 9492db270a8SFrederic Weisbecker const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) 9502db270a8SFrederic Weisbecker { 9512db270a8SFrederic Weisbecker return (const struct blk_io_trace *)ent; 9522db270a8SFrederic Weisbecker } 9532db270a8SFrederic Weisbecker 9542db270a8SFrederic Weisbecker static inline const void *pdu_start(const struct trace_entry *ent) 9552db270a8SFrederic Weisbecker { 9562db270a8SFrederic Weisbecker return te_blk_io_trace(ent) + 1; 9572db270a8SFrederic Weisbecker } 9582db270a8SFrederic Weisbecker 9592db270a8SFrederic Weisbecker static inline u32 t_sec(const struct trace_entry *ent) 9602db270a8SFrederic Weisbecker { 9612db270a8SFrederic Weisbecker return te_blk_io_trace(ent)->bytes >> 9; 9622db270a8SFrederic Weisbecker } 9632db270a8SFrederic Weisbecker 9642db270a8SFrederic Weisbecker static inline unsigned long long t_sector(const struct trace_entry *ent) 9652db270a8SFrederic Weisbecker { 9662db270a8SFrederic Weisbecker return te_blk_io_trace(ent)->sector; 9672db270a8SFrederic Weisbecker } 9682db270a8SFrederic Weisbecker 9692db270a8SFrederic Weisbecker static inline __u16 t_error(const struct trace_entry *ent) 9702db270a8SFrederic Weisbecker { 9712db270a8SFrederic Weisbecker return te_blk_io_trace(ent)->sector; 9722db270a8SFrederic Weisbecker } 9732db270a8SFrederic Weisbecker 9742db270a8SFrederic Weisbecker static __u64 get_pdu_int(const struct trace_entry *ent) 9752db270a8SFrederic Weisbecker { 9762db270a8SFrederic Weisbecker const __u64 *val = pdu_start(ent); 9772db270a8SFrederic Weisbecker return be64_to_cpu(*val); 9782db270a8SFrederic Weisbecker } 9792db270a8SFrederic Weisbecker 9802db270a8SFrederic Weisbecker static void get_pdu_remap(const struct trace_entry *ent, 9812db270a8SFrederic Weisbecker struct blk_io_trace_remap *r) 9822db270a8SFrederic Weisbecker { 9832db270a8SFrederic Weisbecker const struct blk_io_trace_remap *__r = pdu_start(ent); 9842db270a8SFrederic Weisbecker __u64 sector = __r->sector; 9852db270a8SFrederic Weisbecker 9862db270a8SFrederic Weisbecker r->device = be32_to_cpu(__r->device); 9872db270a8SFrederic Weisbecker r->device_from = be32_to_cpu(__r->device_from); 9882db270a8SFrederic Weisbecker r->sector = be64_to_cpu(sector); 9892db270a8SFrederic Weisbecker } 9902db270a8SFrederic Weisbecker 9912db270a8SFrederic Weisbecker static int blk_log_action_iter(struct trace_iterator *iter, const char *act) 9922db270a8SFrederic Weisbecker { 9932db270a8SFrederic Weisbecker char rwbs[6]; 9942db270a8SFrederic Weisbecker unsigned long long ts = ns2usecs(iter->ts); 9952db270a8SFrederic Weisbecker unsigned long usec_rem = do_div(ts, USEC_PER_SEC); 9962db270a8SFrederic Weisbecker unsigned secs = (unsigned long)ts; 9972db270a8SFrederic Weisbecker const struct trace_entry *ent = iter->ent; 9982db270a8SFrederic Weisbecker const struct blk_io_trace *t = (const struct blk_io_trace *)ent; 9992db270a8SFrederic Weisbecker 10002db270a8SFrederic Weisbecker fill_rwbs(rwbs, t); 10012db270a8SFrederic Weisbecker 10022db270a8SFrederic Weisbecker return trace_seq_printf(&iter->seq, 10032db270a8SFrederic Weisbecker "%3d,%-3d %2d %5d.%06lu %5u %2s %3s ", 10042db270a8SFrederic Weisbecker MAJOR(t->device), MINOR(t->device), iter->cpu, 10052db270a8SFrederic Weisbecker secs, usec_rem, ent->pid, act, rwbs); 10062db270a8SFrederic Weisbecker } 10072db270a8SFrederic Weisbecker 10082db270a8SFrederic Weisbecker static int blk_log_action_seq(struct trace_seq *s, const struct blk_io_trace *t, 10092db270a8SFrederic Weisbecker const char *act) 10102db270a8SFrederic Weisbecker { 10112db270a8SFrederic Weisbecker char rwbs[6]; 10122db270a8SFrederic Weisbecker fill_rwbs(rwbs, t); 10132db270a8SFrederic Weisbecker return trace_seq_printf(s, "%3d,%-3d %2s %3s ", 10142db270a8SFrederic Weisbecker MAJOR(t->device), MINOR(t->device), act, rwbs); 10152db270a8SFrederic Weisbecker } 10162db270a8SFrederic Weisbecker 10172db270a8SFrederic Weisbecker static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) 10182db270a8SFrederic Weisbecker { 10194ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 10204ca53085SSteven Rostedt 10214ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 10222db270a8SFrederic Weisbecker 10232db270a8SFrederic Weisbecker if (t_sec(ent)) 10242db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu + %u [%s]\n", 10252db270a8SFrederic Weisbecker t_sector(ent), t_sec(ent), cmd); 10262db270a8SFrederic Weisbecker return trace_seq_printf(s, "[%s]\n", cmd); 10272db270a8SFrederic Weisbecker } 10282db270a8SFrederic Weisbecker 10292db270a8SFrederic Weisbecker static int blk_log_with_error(struct trace_seq *s, 10302db270a8SFrederic Weisbecker const struct trace_entry *ent) 10312db270a8SFrederic Weisbecker { 10322db270a8SFrederic Weisbecker if (t_sec(ent)) 10332db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu + %u [%d]\n", t_sector(ent), 10342db270a8SFrederic Weisbecker t_sec(ent), t_error(ent)); 10352db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu [%d]\n", t_sector(ent), t_error(ent)); 10362db270a8SFrederic Weisbecker } 10372db270a8SFrederic Weisbecker 10382db270a8SFrederic Weisbecker static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) 10392db270a8SFrederic Weisbecker { 10402db270a8SFrederic Weisbecker struct blk_io_trace_remap r = { .device = 0, }; 10412db270a8SFrederic Weisbecker 10422db270a8SFrederic Weisbecker get_pdu_remap(ent, &r); 10432db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", 10442db270a8SFrederic Weisbecker t_sector(ent), 10452db270a8SFrederic Weisbecker t_sec(ent), MAJOR(r.device), MINOR(r.device), 10462db270a8SFrederic Weisbecker (unsigned long long)r.sector); 10472db270a8SFrederic Weisbecker } 10482db270a8SFrederic Weisbecker 10492db270a8SFrederic Weisbecker static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) 10502db270a8SFrederic Weisbecker { 10514ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 10524ca53085SSteven Rostedt 10534ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 10544ca53085SSteven Rostedt 10554ca53085SSteven Rostedt return trace_seq_printf(s, "[%s]\n", cmd); 10562db270a8SFrederic Weisbecker } 10572db270a8SFrederic Weisbecker 10582db270a8SFrederic Weisbecker static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) 10592db270a8SFrederic Weisbecker { 10604ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 10614ca53085SSteven Rostedt 10624ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 10634ca53085SSteven Rostedt 10644ca53085SSteven Rostedt return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); 10652db270a8SFrederic Weisbecker } 10662db270a8SFrederic Weisbecker 10672db270a8SFrederic Weisbecker static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) 10682db270a8SFrederic Weisbecker { 10694ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 10704ca53085SSteven Rostedt 10714ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 10724ca53085SSteven Rostedt 10732db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), 10744ca53085SSteven Rostedt get_pdu_int(ent), cmd); 10752db270a8SFrederic Weisbecker } 10762db270a8SFrederic Weisbecker 10772db270a8SFrederic Weisbecker /* 10782db270a8SFrederic Weisbecker * struct tracer operations 10792db270a8SFrederic Weisbecker */ 10802db270a8SFrederic Weisbecker 10812db270a8SFrederic Weisbecker static void blk_tracer_print_header(struct seq_file *m) 10822db270a8SFrederic Weisbecker { 10832db270a8SFrederic Weisbecker if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) 10842db270a8SFrederic Weisbecker return; 10852db270a8SFrederic Weisbecker seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" 10862db270a8SFrederic Weisbecker "# | | | | | |\n"); 10872db270a8SFrederic Weisbecker } 10882db270a8SFrederic Weisbecker 10892db270a8SFrederic Weisbecker static void blk_tracer_start(struct trace_array *tr) 10902db270a8SFrederic Weisbecker { 10912db270a8SFrederic Weisbecker if (atomic_add_return(1, &blk_probes_ref) == 1) 10923c289ba7SLi Zefan blk_register_tracepoints(); 10932db270a8SFrederic Weisbecker trace_flags &= ~TRACE_ITER_CONTEXT_INFO; 10942db270a8SFrederic Weisbecker } 10952db270a8SFrederic Weisbecker 10962db270a8SFrederic Weisbecker static int blk_tracer_init(struct trace_array *tr) 10972db270a8SFrederic Weisbecker { 10982db270a8SFrederic Weisbecker blk_tr = tr; 10992db270a8SFrederic Weisbecker blk_tracer_start(tr); 11005006ea73SLi Zefan blk_tracer_enabled = true; 11012db270a8SFrederic Weisbecker return 0; 11022db270a8SFrederic Weisbecker } 11032db270a8SFrederic Weisbecker 11042db270a8SFrederic Weisbecker static void blk_tracer_stop(struct trace_array *tr) 11052db270a8SFrederic Weisbecker { 11062db270a8SFrederic Weisbecker trace_flags |= TRACE_ITER_CONTEXT_INFO; 11072db270a8SFrederic Weisbecker if (atomic_dec_and_test(&blk_probes_ref)) 11082db270a8SFrederic Weisbecker blk_unregister_tracepoints(); 11092db270a8SFrederic Weisbecker } 11102db270a8SFrederic Weisbecker 11112db270a8SFrederic Weisbecker static void blk_tracer_reset(struct trace_array *tr) 11122db270a8SFrederic Weisbecker { 11132db270a8SFrederic Weisbecker if (!atomic_read(&blk_probes_ref)) 11142db270a8SFrederic Weisbecker return; 11152db270a8SFrederic Weisbecker 11165006ea73SLi Zefan blk_tracer_enabled = false; 11172db270a8SFrederic Weisbecker blk_tracer_stop(tr); 11182db270a8SFrederic Weisbecker } 11192db270a8SFrederic Weisbecker 1120e4955c99SLi Zefan static const struct { 11212db270a8SFrederic Weisbecker const char *act[2]; 11222db270a8SFrederic Weisbecker int (*print)(struct trace_seq *s, const struct trace_entry *ent); 1123e4955c99SLi Zefan } what2act[] = { 11242db270a8SFrederic Weisbecker [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, 11252db270a8SFrederic Weisbecker [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, 11262db270a8SFrederic Weisbecker [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, 11272db270a8SFrederic Weisbecker [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, 11282db270a8SFrederic Weisbecker [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, 11292db270a8SFrederic Weisbecker [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, 11302db270a8SFrederic Weisbecker [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, 11312db270a8SFrederic Weisbecker [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, 11322db270a8SFrederic Weisbecker [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, 11332db270a8SFrederic Weisbecker [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, 11342db270a8SFrederic Weisbecker [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, 11352db270a8SFrederic Weisbecker [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, 11362db270a8SFrederic Weisbecker [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, 11372db270a8SFrederic Weisbecker [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, 11382db270a8SFrederic Weisbecker [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, 11392db270a8SFrederic Weisbecker }; 11402db270a8SFrederic Weisbecker 11412db270a8SFrederic Weisbecker static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, 11422db270a8SFrederic Weisbecker int flags) 11432db270a8SFrederic Weisbecker { 11442db270a8SFrederic Weisbecker struct trace_seq *s = &iter->seq; 11452db270a8SFrederic Weisbecker const struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; 11462db270a8SFrederic Weisbecker const u16 what = t->action & ((1 << BLK_TC_SHIFT) - 1); 11472db270a8SFrederic Weisbecker int ret; 11482db270a8SFrederic Weisbecker 11492db270a8SFrederic Weisbecker if (!trace_print_context(iter)) 11502db270a8SFrederic Weisbecker return TRACE_TYPE_PARTIAL_LINE; 11512db270a8SFrederic Weisbecker 11522db270a8SFrederic Weisbecker if (unlikely(what == 0 || what > ARRAY_SIZE(what2act))) 11532db270a8SFrederic Weisbecker ret = trace_seq_printf(s, "Bad pc action %x\n", what); 11542db270a8SFrederic Weisbecker else { 11552db270a8SFrederic Weisbecker const bool long_act = !!(trace_flags & TRACE_ITER_VERBOSE); 11562db270a8SFrederic Weisbecker ret = blk_log_action_seq(s, t, what2act[what].act[long_act]); 11572db270a8SFrederic Weisbecker if (ret) 11582db270a8SFrederic Weisbecker ret = what2act[what].print(s, iter->ent); 11592db270a8SFrederic Weisbecker } 11602db270a8SFrederic Weisbecker 11612db270a8SFrederic Weisbecker return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; 11622db270a8SFrederic Weisbecker } 11632db270a8SFrederic Weisbecker 11642db270a8SFrederic Weisbecker static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) 11652db270a8SFrederic Weisbecker { 11662db270a8SFrederic Weisbecker struct trace_seq *s = &iter->seq; 11672db270a8SFrederic Weisbecker struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; 11682db270a8SFrederic Weisbecker const int offset = offsetof(struct blk_io_trace, sector); 11692db270a8SFrederic Weisbecker struct blk_io_trace old = { 11702db270a8SFrederic Weisbecker .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, 11712db270a8SFrederic Weisbecker .time = ns2usecs(iter->ts), 11722db270a8SFrederic Weisbecker }; 11732db270a8SFrederic Weisbecker 11742db270a8SFrederic Weisbecker if (!trace_seq_putmem(s, &old, offset)) 11752db270a8SFrederic Weisbecker return 0; 11762db270a8SFrederic Weisbecker return trace_seq_putmem(s, &t->sector, 11772db270a8SFrederic Weisbecker sizeof(old) - offset + t->pdu_len); 11782db270a8SFrederic Weisbecker } 11792db270a8SFrederic Weisbecker 11802db270a8SFrederic Weisbecker static enum print_line_t 11812db270a8SFrederic Weisbecker blk_trace_event_print_binary(struct trace_iterator *iter, int flags) 11822db270a8SFrederic Weisbecker { 11832db270a8SFrederic Weisbecker return blk_trace_synthesize_old_trace(iter) ? 11842db270a8SFrederic Weisbecker TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; 11852db270a8SFrederic Weisbecker } 11862db270a8SFrederic Weisbecker 11872db270a8SFrederic Weisbecker static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) 11882db270a8SFrederic Weisbecker { 11892db270a8SFrederic Weisbecker const struct blk_io_trace *t; 11902db270a8SFrederic Weisbecker u16 what; 11912db270a8SFrederic Weisbecker int ret; 11922db270a8SFrederic Weisbecker 11932db270a8SFrederic Weisbecker if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) 11942db270a8SFrederic Weisbecker return TRACE_TYPE_UNHANDLED; 11952db270a8SFrederic Weisbecker 11962db270a8SFrederic Weisbecker t = (const struct blk_io_trace *)iter->ent; 11972db270a8SFrederic Weisbecker what = t->action & ((1 << BLK_TC_SHIFT) - 1); 11982db270a8SFrederic Weisbecker 11992db270a8SFrederic Weisbecker if (unlikely(what == 0 || what > ARRAY_SIZE(what2act))) 12002db270a8SFrederic Weisbecker ret = trace_seq_printf(&iter->seq, "Bad pc action %x\n", what); 12012db270a8SFrederic Weisbecker else { 12022db270a8SFrederic Weisbecker const bool long_act = !!(trace_flags & TRACE_ITER_VERBOSE); 12032db270a8SFrederic Weisbecker ret = blk_log_action_iter(iter, what2act[what].act[long_act]); 12042db270a8SFrederic Weisbecker if (ret) 12052db270a8SFrederic Weisbecker ret = what2act[what].print(&iter->seq, iter->ent); 12062db270a8SFrederic Weisbecker } 12072db270a8SFrederic Weisbecker 12082db270a8SFrederic Weisbecker return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; 12092db270a8SFrederic Weisbecker } 12102db270a8SFrederic Weisbecker 12112db270a8SFrederic Weisbecker static struct tracer blk_tracer __read_mostly = { 12122db270a8SFrederic Weisbecker .name = "blk", 12132db270a8SFrederic Weisbecker .init = blk_tracer_init, 12142db270a8SFrederic Weisbecker .reset = blk_tracer_reset, 12152db270a8SFrederic Weisbecker .start = blk_tracer_start, 12162db270a8SFrederic Weisbecker .stop = blk_tracer_stop, 12172db270a8SFrederic Weisbecker .print_header = blk_tracer_print_header, 12182db270a8SFrederic Weisbecker .print_line = blk_tracer_print_line, 12192db270a8SFrederic Weisbecker .flags = &blk_tracer_flags, 12202db270a8SFrederic Weisbecker }; 12212db270a8SFrederic Weisbecker 12222db270a8SFrederic Weisbecker static struct trace_event trace_blk_event = { 12232db270a8SFrederic Weisbecker .type = TRACE_BLK, 12242db270a8SFrederic Weisbecker .trace = blk_trace_event_print, 12252db270a8SFrederic Weisbecker .binary = blk_trace_event_print_binary, 12262db270a8SFrederic Weisbecker }; 12272db270a8SFrederic Weisbecker 12282db270a8SFrederic Weisbecker static int __init init_blk_tracer(void) 12292db270a8SFrederic Weisbecker { 12302db270a8SFrederic Weisbecker if (!register_ftrace_event(&trace_blk_event)) { 12312db270a8SFrederic Weisbecker pr_warning("Warning: could not register block events\n"); 12322db270a8SFrederic Weisbecker return 1; 12332db270a8SFrederic Weisbecker } 12342db270a8SFrederic Weisbecker 12352db270a8SFrederic Weisbecker if (register_tracer(&blk_tracer) != 0) { 12362db270a8SFrederic Weisbecker pr_warning("Warning: could not register the block tracer\n"); 12372db270a8SFrederic Weisbecker unregister_ftrace_event(&trace_blk_event); 12382db270a8SFrederic Weisbecker return 1; 12392db270a8SFrederic Weisbecker } 12402db270a8SFrederic Weisbecker 12412db270a8SFrederic Weisbecker return 0; 12422db270a8SFrederic Weisbecker } 12432db270a8SFrederic Weisbecker 12442db270a8SFrederic Weisbecker device_initcall(init_blk_tracer); 12452db270a8SFrederic Weisbecker 12462db270a8SFrederic Weisbecker static int blk_trace_remove_queue(struct request_queue *q) 12472db270a8SFrederic Weisbecker { 12482db270a8SFrederic Weisbecker struct blk_trace *bt; 12492db270a8SFrederic Weisbecker 12502db270a8SFrederic Weisbecker bt = xchg(&q->blk_trace, NULL); 12512db270a8SFrederic Weisbecker if (bt == NULL) 12522db270a8SFrederic Weisbecker return -EINVAL; 12532db270a8SFrederic Weisbecker 12542db270a8SFrederic Weisbecker kfree(bt); 12552db270a8SFrederic Weisbecker return 0; 12562db270a8SFrederic Weisbecker } 12572db270a8SFrederic Weisbecker 12582db270a8SFrederic Weisbecker /* 12592db270a8SFrederic Weisbecker * Setup everything required to start tracing 12602db270a8SFrederic Weisbecker */ 12612db270a8SFrederic Weisbecker static int blk_trace_setup_queue(struct request_queue *q, dev_t dev) 12622db270a8SFrederic Weisbecker { 12632db270a8SFrederic Weisbecker struct blk_trace *old_bt, *bt = NULL; 12642db270a8SFrederic Weisbecker 12652db270a8SFrederic Weisbecker bt = kzalloc(sizeof(*bt), GFP_KERNEL); 12662db270a8SFrederic Weisbecker if (!bt) 126715152e44SLi Zefan return -ENOMEM; 12682db270a8SFrederic Weisbecker 12692db270a8SFrederic Weisbecker bt->dev = dev; 12702db270a8SFrederic Weisbecker bt->act_mask = (u16)-1; 12712db270a8SFrederic Weisbecker bt->end_lba = -1ULL; 12722db270a8SFrederic Weisbecker bt->trace_state = Blktrace_running; 12732db270a8SFrederic Weisbecker 12742db270a8SFrederic Weisbecker old_bt = xchg(&q->blk_trace, bt); 12752db270a8SFrederic Weisbecker if (old_bt != NULL) { 12762db270a8SFrederic Weisbecker (void)xchg(&q->blk_trace, old_bt); 12772db270a8SFrederic Weisbecker kfree(bt); 127815152e44SLi Zefan return -EBUSY; 12792db270a8SFrederic Weisbecker } 128015152e44SLi Zefan 12812db270a8SFrederic Weisbecker return 0; 12822db270a8SFrederic Weisbecker } 12832db270a8SFrederic Weisbecker 12842db270a8SFrederic Weisbecker /* 12852db270a8SFrederic Weisbecker * sysfs interface to enable and configure tracing 12862db270a8SFrederic Weisbecker */ 12872db270a8SFrederic Weisbecker 12882db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_show(struct device *dev, 12892db270a8SFrederic Weisbecker struct device_attribute *attr, 12902db270a8SFrederic Weisbecker char *buf); 12912db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_store(struct device *dev, 12922db270a8SFrederic Weisbecker struct device_attribute *attr, 12932db270a8SFrederic Weisbecker const char *buf, size_t count); 12942db270a8SFrederic Weisbecker #define BLK_TRACE_DEVICE_ATTR(_name) \ 12952db270a8SFrederic Weisbecker DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ 12962db270a8SFrederic Weisbecker sysfs_blk_trace_attr_show, \ 12972db270a8SFrederic Weisbecker sysfs_blk_trace_attr_store) 12982db270a8SFrederic Weisbecker 1299cd649b8bSLi Zefan static BLK_TRACE_DEVICE_ATTR(enable); 13002db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(act_mask); 13012db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(pid); 13022db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(start_lba); 13032db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(end_lba); 13042db270a8SFrederic Weisbecker 13052db270a8SFrederic Weisbecker static struct attribute *blk_trace_attrs[] = { 13062db270a8SFrederic Weisbecker &dev_attr_enable.attr, 13072db270a8SFrederic Weisbecker &dev_attr_act_mask.attr, 13082db270a8SFrederic Weisbecker &dev_attr_pid.attr, 13092db270a8SFrederic Weisbecker &dev_attr_start_lba.attr, 13102db270a8SFrederic Weisbecker &dev_attr_end_lba.attr, 13112db270a8SFrederic Weisbecker NULL 13122db270a8SFrederic Weisbecker }; 13132db270a8SFrederic Weisbecker 13142db270a8SFrederic Weisbecker struct attribute_group blk_trace_attr_group = { 13152db270a8SFrederic Weisbecker .name = "trace", 13162db270a8SFrederic Weisbecker .attrs = blk_trace_attrs, 13172db270a8SFrederic Weisbecker }; 13182db270a8SFrederic Weisbecker 13192db270a8SFrederic Weisbecker static int blk_str2act_mask(const char *str) 13202db270a8SFrederic Weisbecker { 13212db270a8SFrederic Weisbecker int mask = 0; 13222db270a8SFrederic Weisbecker char *copy = kstrdup(str, GFP_KERNEL), *s; 13232db270a8SFrederic Weisbecker 13242db270a8SFrederic Weisbecker if (copy == NULL) 13252db270a8SFrederic Weisbecker return -ENOMEM; 13262db270a8SFrederic Weisbecker 13272db270a8SFrederic Weisbecker s = strstrip(copy); 13282db270a8SFrederic Weisbecker 13292db270a8SFrederic Weisbecker while (1) { 13302db270a8SFrederic Weisbecker char *sep = strchr(s, ','); 13312db270a8SFrederic Weisbecker 13322db270a8SFrederic Weisbecker if (sep != NULL) 13332db270a8SFrederic Weisbecker *sep = '\0'; 13342db270a8SFrederic Weisbecker 13352db270a8SFrederic Weisbecker if (strcasecmp(s, "barrier") == 0) 13362db270a8SFrederic Weisbecker mask |= BLK_TC_BARRIER; 13372db270a8SFrederic Weisbecker else if (strcasecmp(s, "complete") == 0) 13382db270a8SFrederic Weisbecker mask |= BLK_TC_COMPLETE; 13392db270a8SFrederic Weisbecker else if (strcasecmp(s, "fs") == 0) 13402db270a8SFrederic Weisbecker mask |= BLK_TC_FS; 13412db270a8SFrederic Weisbecker else if (strcasecmp(s, "issue") == 0) 13422db270a8SFrederic Weisbecker mask |= BLK_TC_ISSUE; 13432db270a8SFrederic Weisbecker else if (strcasecmp(s, "pc") == 0) 13442db270a8SFrederic Weisbecker mask |= BLK_TC_PC; 13452db270a8SFrederic Weisbecker else if (strcasecmp(s, "queue") == 0) 13462db270a8SFrederic Weisbecker mask |= BLK_TC_QUEUE; 13472db270a8SFrederic Weisbecker else if (strcasecmp(s, "read") == 0) 13482db270a8SFrederic Weisbecker mask |= BLK_TC_READ; 13492db270a8SFrederic Weisbecker else if (strcasecmp(s, "requeue") == 0) 13502db270a8SFrederic Weisbecker mask |= BLK_TC_REQUEUE; 13512db270a8SFrederic Weisbecker else if (strcasecmp(s, "sync") == 0) 13522db270a8SFrederic Weisbecker mask |= BLK_TC_SYNC; 13532db270a8SFrederic Weisbecker else if (strcasecmp(s, "write") == 0) 13542db270a8SFrederic Weisbecker mask |= BLK_TC_WRITE; 13552db270a8SFrederic Weisbecker 13562db270a8SFrederic Weisbecker if (sep == NULL) 13572db270a8SFrederic Weisbecker break; 13582db270a8SFrederic Weisbecker 13592db270a8SFrederic Weisbecker s = sep + 1; 13602db270a8SFrederic Weisbecker } 13612db270a8SFrederic Weisbecker kfree(copy); 13622db270a8SFrederic Weisbecker 13632db270a8SFrederic Weisbecker return mask; 13642db270a8SFrederic Weisbecker } 13652db270a8SFrederic Weisbecker 1366b125130bSLi Zefan static struct request_queue *blk_trace_get_queue(struct block_device *bdev) 1367b125130bSLi Zefan { 1368b125130bSLi Zefan if (bdev->bd_disk == NULL) 1369b125130bSLi Zefan return NULL; 1370b125130bSLi Zefan 1371b125130bSLi Zefan return bdev_get_queue(bdev); 1372b125130bSLi Zefan } 1373b125130bSLi Zefan 13742db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_show(struct device *dev, 13752db270a8SFrederic Weisbecker struct device_attribute *attr, 13762db270a8SFrederic Weisbecker char *buf) 13772db270a8SFrederic Weisbecker { 13782db270a8SFrederic Weisbecker struct hd_struct *p = dev_to_part(dev); 13792db270a8SFrederic Weisbecker struct request_queue *q; 13802db270a8SFrederic Weisbecker struct block_device *bdev; 13812db270a8SFrederic Weisbecker ssize_t ret = -ENXIO; 13822db270a8SFrederic Weisbecker 13832db270a8SFrederic Weisbecker lock_kernel(); 13842db270a8SFrederic Weisbecker bdev = bdget(part_devt(p)); 13852db270a8SFrederic Weisbecker if (bdev == NULL) 13862db270a8SFrederic Weisbecker goto out_unlock_kernel; 13872db270a8SFrederic Weisbecker 1388b125130bSLi Zefan q = blk_trace_get_queue(bdev); 13892db270a8SFrederic Weisbecker if (q == NULL) 13902db270a8SFrederic Weisbecker goto out_bdput; 1391b125130bSLi Zefan 13922db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 1393cd649b8bSLi Zefan 1394cd649b8bSLi Zefan if (attr == &dev_attr_enable) { 1395cd649b8bSLi Zefan ret = sprintf(buf, "%u\n", !!q->blk_trace); 1396cd649b8bSLi Zefan goto out_unlock_bdev; 1397cd649b8bSLi Zefan } 1398cd649b8bSLi Zefan 13992db270a8SFrederic Weisbecker if (q->blk_trace == NULL) 14002db270a8SFrederic Weisbecker ret = sprintf(buf, "disabled\n"); 14012db270a8SFrederic Weisbecker else if (attr == &dev_attr_act_mask) 14022db270a8SFrederic Weisbecker ret = sprintf(buf, "%#x\n", q->blk_trace->act_mask); 14032db270a8SFrederic Weisbecker else if (attr == &dev_attr_pid) 14042db270a8SFrederic Weisbecker ret = sprintf(buf, "%u\n", q->blk_trace->pid); 14052db270a8SFrederic Weisbecker else if (attr == &dev_attr_start_lba) 14062db270a8SFrederic Weisbecker ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); 14072db270a8SFrederic Weisbecker else if (attr == &dev_attr_end_lba) 14082db270a8SFrederic Weisbecker ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); 1409cd649b8bSLi Zefan 1410cd649b8bSLi Zefan out_unlock_bdev: 14112db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 14122db270a8SFrederic Weisbecker out_bdput: 14132db270a8SFrederic Weisbecker bdput(bdev); 14142db270a8SFrederic Weisbecker out_unlock_kernel: 14152db270a8SFrederic Weisbecker unlock_kernel(); 14162db270a8SFrederic Weisbecker return ret; 14172db270a8SFrederic Weisbecker } 14182db270a8SFrederic Weisbecker 14192db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_store(struct device *dev, 14202db270a8SFrederic Weisbecker struct device_attribute *attr, 14212db270a8SFrederic Weisbecker const char *buf, size_t count) 14222db270a8SFrederic Weisbecker { 14232db270a8SFrederic Weisbecker struct block_device *bdev; 14242db270a8SFrederic Weisbecker struct request_queue *q; 14252db270a8SFrederic Weisbecker struct hd_struct *p; 14262db270a8SFrederic Weisbecker u64 value; 14272db270a8SFrederic Weisbecker ssize_t ret = -ENXIO; 14282db270a8SFrederic Weisbecker 14292db270a8SFrederic Weisbecker if (count == 0) 14302db270a8SFrederic Weisbecker goto out; 14312db270a8SFrederic Weisbecker 14322db270a8SFrederic Weisbecker if (attr == &dev_attr_act_mask) { 14332db270a8SFrederic Weisbecker if (sscanf(buf, "%llx", &value) != 1) { 14342db270a8SFrederic Weisbecker /* Assume it is a list of trace category names */ 14352db270a8SFrederic Weisbecker value = blk_str2act_mask(buf); 14362db270a8SFrederic Weisbecker if (value < 0) 14372db270a8SFrederic Weisbecker goto out; 14382db270a8SFrederic Weisbecker } 14392db270a8SFrederic Weisbecker } else if (sscanf(buf, "%llu", &value) != 1) 14402db270a8SFrederic Weisbecker goto out; 14412db270a8SFrederic Weisbecker 14422db270a8SFrederic Weisbecker lock_kernel(); 14432db270a8SFrederic Weisbecker p = dev_to_part(dev); 14442db270a8SFrederic Weisbecker bdev = bdget(part_devt(p)); 14452db270a8SFrederic Weisbecker if (bdev == NULL) 14462db270a8SFrederic Weisbecker goto out_unlock_kernel; 14472db270a8SFrederic Weisbecker 1448b125130bSLi Zefan q = blk_trace_get_queue(bdev); 14492db270a8SFrederic Weisbecker if (q == NULL) 14502db270a8SFrederic Weisbecker goto out_bdput; 14512db270a8SFrederic Weisbecker 14522db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 1453cd649b8bSLi Zefan 1454cd649b8bSLi Zefan if (attr == &dev_attr_enable) { 1455cd649b8bSLi Zefan if (value) 1456cd649b8bSLi Zefan ret = blk_trace_setup_queue(q, bdev->bd_dev); 1457cd649b8bSLi Zefan else 1458cd649b8bSLi Zefan ret = blk_trace_remove_queue(q); 1459cd649b8bSLi Zefan goto out_unlock_bdev; 1460cd649b8bSLi Zefan } 1461cd649b8bSLi Zefan 14622db270a8SFrederic Weisbecker ret = 0; 14632db270a8SFrederic Weisbecker if (q->blk_trace == NULL) 14642db270a8SFrederic Weisbecker ret = blk_trace_setup_queue(q, bdev->bd_dev); 14652db270a8SFrederic Weisbecker 14662db270a8SFrederic Weisbecker if (ret == 0) { 14672db270a8SFrederic Weisbecker if (attr == &dev_attr_act_mask) 14682db270a8SFrederic Weisbecker q->blk_trace->act_mask = value; 14692db270a8SFrederic Weisbecker else if (attr == &dev_attr_pid) 14702db270a8SFrederic Weisbecker q->blk_trace->pid = value; 14712db270a8SFrederic Weisbecker else if (attr == &dev_attr_start_lba) 14722db270a8SFrederic Weisbecker q->blk_trace->start_lba = value; 14732db270a8SFrederic Weisbecker else if (attr == &dev_attr_end_lba) 14742db270a8SFrederic Weisbecker q->blk_trace->end_lba = value; 14752db270a8SFrederic Weisbecker } 1476cd649b8bSLi Zefan 1477cd649b8bSLi Zefan out_unlock_bdev: 14782db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 14792db270a8SFrederic Weisbecker out_bdput: 14802db270a8SFrederic Weisbecker bdput(bdev); 14812db270a8SFrederic Weisbecker out_unlock_kernel: 14822db270a8SFrederic Weisbecker unlock_kernel(); 14832db270a8SFrederic Weisbecker out: 1484cd649b8bSLi Zefan return ret ? ret : count; 14852db270a8SFrederic Weisbecker } 1486cd649b8bSLi Zefan 1487