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> 245a0e3ad6STejun Heo #include <linux/slab.h> 252db270a8SFrederic Weisbecker #include <linux/debugfs.h> 266e5fdeedSPaul Gortmaker #include <linux/export.h> 272db270a8SFrederic Weisbecker #include <linux/time.h> 282db270a8SFrederic Weisbecker #include <linux/uaccess.h> 2955782138SLi Zefan 3055782138SLi Zefan #include <trace/events/block.h> 3155782138SLi Zefan 322db270a8SFrederic Weisbecker #include "trace_output.h" 332db270a8SFrederic Weisbecker 3455782138SLi Zefan #ifdef CONFIG_BLK_DEV_IO_TRACE 3555782138SLi Zefan 362db270a8SFrederic Weisbecker static unsigned int blktrace_seq __read_mostly = 1; 372db270a8SFrederic Weisbecker 382db270a8SFrederic Weisbecker static struct trace_array *blk_tr; 395006ea73SLi Zefan static bool blk_tracer_enabled __read_mostly; 402db270a8SFrederic Weisbecker 412db270a8SFrederic Weisbecker /* Select an alternative, minimalistic output than the original one */ 422db270a8SFrederic Weisbecker #define TRACE_BLK_OPT_CLASSIC 0x1 432db270a8SFrederic Weisbecker 442db270a8SFrederic Weisbecker static struct tracer_opt blk_tracer_opts[] = { 452db270a8SFrederic Weisbecker /* Default disable the minimalistic output */ 462db270a8SFrederic Weisbecker { TRACER_OPT(blk_classic, TRACE_BLK_OPT_CLASSIC) }, 472db270a8SFrederic Weisbecker { } 482db270a8SFrederic Weisbecker }; 492db270a8SFrederic Weisbecker 502db270a8SFrederic Weisbecker static struct tracer_flags blk_tracer_flags = { 512db270a8SFrederic Weisbecker .val = 0, 522db270a8SFrederic Weisbecker .opts = blk_tracer_opts, 532db270a8SFrederic Weisbecker }; 542db270a8SFrederic Weisbecker 552db270a8SFrederic Weisbecker /* Global reference count of probes */ 562db270a8SFrederic Weisbecker static atomic_t blk_probes_ref = ATOMIC_INIT(0); 572db270a8SFrederic Weisbecker 583c289ba7SLi Zefan static void blk_register_tracepoints(void); 592db270a8SFrederic Weisbecker static void blk_unregister_tracepoints(void); 602db270a8SFrederic Weisbecker 612db270a8SFrederic Weisbecker /* 622db270a8SFrederic Weisbecker * Send out a notify message. 632db270a8SFrederic Weisbecker */ 642db270a8SFrederic Weisbecker static void trace_note(struct blk_trace *bt, pid_t pid, int action, 652db270a8SFrederic Weisbecker const void *data, size_t len) 662db270a8SFrederic Weisbecker { 672db270a8SFrederic Weisbecker struct blk_io_trace *t; 6818cea459SLi Zefan struct ring_buffer_event *event = NULL; 69e77405adSSteven Rostedt struct ring_buffer *buffer = NULL; 7018cea459SLi Zefan int pc = 0; 7118cea459SLi Zefan int cpu = smp_processor_id(); 7218cea459SLi Zefan bool blk_tracer = blk_tracer_enabled; 7318cea459SLi Zefan 7418cea459SLi Zefan if (blk_tracer) { 75e77405adSSteven Rostedt buffer = blk_tr->buffer; 7618cea459SLi Zefan pc = preempt_count(); 77e77405adSSteven Rostedt event = trace_buffer_lock_reserve(buffer, TRACE_BLK, 7818cea459SLi Zefan sizeof(*t) + len, 7918cea459SLi Zefan 0, pc); 8018cea459SLi Zefan if (!event) 8118cea459SLi Zefan return; 8218cea459SLi Zefan t = ring_buffer_event_data(event); 8318cea459SLi Zefan goto record_it; 8418cea459SLi Zefan } 852db270a8SFrederic Weisbecker 862db270a8SFrederic Weisbecker if (!bt->rchan) 872db270a8SFrederic Weisbecker return; 882db270a8SFrederic Weisbecker 892db270a8SFrederic Weisbecker t = relay_reserve(bt->rchan, sizeof(*t) + len); 902db270a8SFrederic Weisbecker if (t) { 912db270a8SFrederic Weisbecker t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; 922db270a8SFrederic Weisbecker t->time = ktime_to_ns(ktime_get()); 9318cea459SLi Zefan record_it: 942db270a8SFrederic Weisbecker t->device = bt->dev; 952db270a8SFrederic Weisbecker t->action = action; 962db270a8SFrederic Weisbecker t->pid = pid; 972db270a8SFrederic Weisbecker t->cpu = cpu; 982db270a8SFrederic Weisbecker t->pdu_len = len; 992db270a8SFrederic Weisbecker memcpy((void *) t + sizeof(*t), data, len); 10018cea459SLi Zefan 10118cea459SLi Zefan if (blk_tracer) 102e77405adSSteven Rostedt trace_buffer_unlock_commit(buffer, event, 0, pc); 1032db270a8SFrederic Weisbecker } 1042db270a8SFrederic Weisbecker } 1052db270a8SFrederic Weisbecker 1062db270a8SFrederic Weisbecker /* 1072db270a8SFrederic Weisbecker * Send out a notify for this process, if we haven't done so since a trace 1082db270a8SFrederic Weisbecker * started 1092db270a8SFrederic Weisbecker */ 1102db270a8SFrederic Weisbecker static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) 1112db270a8SFrederic Weisbecker { 1122db270a8SFrederic Weisbecker tsk->btrace_seq = blktrace_seq; 1132db270a8SFrederic Weisbecker trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm)); 1142db270a8SFrederic Weisbecker } 1152db270a8SFrederic Weisbecker 1162db270a8SFrederic Weisbecker static void trace_note_time(struct blk_trace *bt) 1172db270a8SFrederic Weisbecker { 1182db270a8SFrederic Weisbecker struct timespec now; 1192db270a8SFrederic Weisbecker unsigned long flags; 1202db270a8SFrederic Weisbecker u32 words[2]; 1212db270a8SFrederic Weisbecker 1222db270a8SFrederic Weisbecker getnstimeofday(&now); 1232db270a8SFrederic Weisbecker words[0] = now.tv_sec; 1242db270a8SFrederic Weisbecker words[1] = now.tv_nsec; 1252db270a8SFrederic Weisbecker 1262db270a8SFrederic Weisbecker local_irq_save(flags); 1272db270a8SFrederic Weisbecker trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words)); 1282db270a8SFrederic Weisbecker local_irq_restore(flags); 1292db270a8SFrederic Weisbecker } 1302db270a8SFrederic Weisbecker 1312db270a8SFrederic Weisbecker void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) 1322db270a8SFrederic Weisbecker { 1332db270a8SFrederic Weisbecker int n; 1342db270a8SFrederic Weisbecker va_list args; 1352db270a8SFrederic Weisbecker unsigned long flags; 1362db270a8SFrederic Weisbecker char *buf; 1372db270a8SFrederic Weisbecker 13818cea459SLi Zefan if (unlikely(bt->trace_state != Blktrace_running && 13918cea459SLi Zefan !blk_tracer_enabled)) 1402db270a8SFrederic Weisbecker return; 1412db270a8SFrederic Weisbecker 142490da40dSTao Ma /* 143490da40dSTao Ma * If the BLK_TC_NOTIFY action mask isn't set, don't send any note 144490da40dSTao Ma * message to the trace. 145490da40dSTao Ma */ 146490da40dSTao Ma if (!(bt->act_mask & BLK_TC_NOTIFY)) 147490da40dSTao Ma return; 148490da40dSTao Ma 1492db270a8SFrederic Weisbecker local_irq_save(flags); 150d8a0349cSShan Wei buf = this_cpu_ptr(bt->msg_data); 1512db270a8SFrederic Weisbecker va_start(args, fmt); 1522db270a8SFrederic Weisbecker n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); 1532db270a8SFrederic Weisbecker va_end(args); 1542db270a8SFrederic Weisbecker 1552db270a8SFrederic Weisbecker trace_note(bt, 0, BLK_TN_MESSAGE, buf, n); 1562db270a8SFrederic Weisbecker local_irq_restore(flags); 1572db270a8SFrederic Weisbecker } 1582db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(__trace_note_message); 1592db270a8SFrederic Weisbecker 1602db270a8SFrederic Weisbecker static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, 1612db270a8SFrederic Weisbecker pid_t pid) 1622db270a8SFrederic Weisbecker { 1632db270a8SFrederic Weisbecker if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) 1642db270a8SFrederic Weisbecker return 1; 165d0deef5bSShawn Du if (sector && (sector < bt->start_lba || sector > bt->end_lba)) 1662db270a8SFrederic Weisbecker return 1; 1672db270a8SFrederic Weisbecker if (bt->pid && pid != bt->pid) 1682db270a8SFrederic Weisbecker return 1; 1692db270a8SFrederic Weisbecker 1702db270a8SFrederic Weisbecker return 0; 1712db270a8SFrederic Weisbecker } 1722db270a8SFrederic Weisbecker 1732db270a8SFrederic Weisbecker /* 1742db270a8SFrederic Weisbecker * Data direction bit lookup 1752db270a8SFrederic Weisbecker */ 176e4955c99SLi Zefan static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ), 1772db270a8SFrederic Weisbecker BLK_TC_ACT(BLK_TC_WRITE) }; 1782db270a8SFrederic Weisbecker 1797b6d91daSChristoph Hellwig #define BLK_TC_RAHEAD BLK_TC_AHEAD 1807b6d91daSChristoph Hellwig 1812db270a8SFrederic Weisbecker /* The ilog2() calls fall out because they're constant */ 1827b6d91daSChristoph Hellwig #define MASK_TC_BIT(rw, __name) ((rw & REQ_ ## __name) << \ 1837b6d91daSChristoph Hellwig (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - __REQ_ ## __name)) 1842db270a8SFrederic Weisbecker 1852db270a8SFrederic Weisbecker /* 1862db270a8SFrederic Weisbecker * The worker for the various blk_add_trace*() types. Fills out a 1872db270a8SFrederic Weisbecker * blk_io_trace structure and places it in a per-cpu subbuffer. 1882db270a8SFrederic Weisbecker */ 1892db270a8SFrederic Weisbecker static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, 1902db270a8SFrederic Weisbecker int rw, u32 what, int error, int pdu_len, void *pdu_data) 1912db270a8SFrederic Weisbecker { 1922db270a8SFrederic Weisbecker struct task_struct *tsk = current; 1932db270a8SFrederic Weisbecker struct ring_buffer_event *event = NULL; 194e77405adSSteven Rostedt struct ring_buffer *buffer = NULL; 1952db270a8SFrederic Weisbecker struct blk_io_trace *t; 1962db270a8SFrederic Weisbecker unsigned long flags = 0; 1972db270a8SFrederic Weisbecker unsigned long *sequence; 1982db270a8SFrederic Weisbecker pid_t pid; 1992db270a8SFrederic Weisbecker int cpu, pc = 0; 20018cea459SLi Zefan bool blk_tracer = blk_tracer_enabled; 2012db270a8SFrederic Weisbecker 20218cea459SLi Zefan if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer)) 2032db270a8SFrederic Weisbecker return; 2042db270a8SFrederic Weisbecker 2052db270a8SFrederic Weisbecker what |= ddir_act[rw & WRITE]; 2067b6d91daSChristoph Hellwig what |= MASK_TC_BIT(rw, SYNC); 2077b6d91daSChristoph Hellwig what |= MASK_TC_BIT(rw, RAHEAD); 2082db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, META); 2092db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, DISCARD); 210c09c47caSNamhyung Kim what |= MASK_TC_BIT(rw, FLUSH); 211c09c47caSNamhyung Kim what |= MASK_TC_BIT(rw, FUA); 2122db270a8SFrederic Weisbecker 2132db270a8SFrederic Weisbecker pid = tsk->pid; 214d0deef5bSShawn Du if (act_log_check(bt, what, sector, pid)) 2152db270a8SFrederic Weisbecker return; 2162db270a8SFrederic Weisbecker cpu = raw_smp_processor_id(); 2172db270a8SFrederic Weisbecker 21818cea459SLi Zefan if (blk_tracer) { 2192db270a8SFrederic Weisbecker tracing_record_cmdline(current); 2202db270a8SFrederic Weisbecker 221e77405adSSteven Rostedt buffer = blk_tr->buffer; 2222db270a8SFrederic Weisbecker pc = preempt_count(); 223e77405adSSteven Rostedt event = trace_buffer_lock_reserve(buffer, TRACE_BLK, 2242db270a8SFrederic Weisbecker sizeof(*t) + pdu_len, 2252db270a8SFrederic Weisbecker 0, pc); 2262db270a8SFrederic Weisbecker if (!event) 2272db270a8SFrederic Weisbecker return; 2282db270a8SFrederic Weisbecker t = ring_buffer_event_data(event); 2292db270a8SFrederic Weisbecker goto record_it; 2302db270a8SFrederic Weisbecker } 2312db270a8SFrederic Weisbecker 2322db270a8SFrederic Weisbecker /* 2332db270a8SFrederic Weisbecker * A word about the locking here - we disable interrupts to reserve 2342db270a8SFrederic Weisbecker * some space in the relay per-cpu buffer, to prevent an irq 2352db270a8SFrederic Weisbecker * from coming in and stepping on our toes. 2362db270a8SFrederic Weisbecker */ 2372db270a8SFrederic Weisbecker local_irq_save(flags); 2382db270a8SFrederic Weisbecker 2392db270a8SFrederic Weisbecker if (unlikely(tsk->btrace_seq != blktrace_seq)) 2402db270a8SFrederic Weisbecker trace_note_tsk(bt, tsk); 2412db270a8SFrederic Weisbecker 2422db270a8SFrederic Weisbecker t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); 2432db270a8SFrederic Weisbecker if (t) { 2442db270a8SFrederic Weisbecker sequence = per_cpu_ptr(bt->sequence, cpu); 2452db270a8SFrederic Weisbecker 2462db270a8SFrederic Weisbecker t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; 2472db270a8SFrederic Weisbecker t->sequence = ++(*sequence); 2482db270a8SFrederic Weisbecker t->time = ktime_to_ns(ktime_get()); 2492db270a8SFrederic Weisbecker record_it: 2502db270a8SFrederic Weisbecker /* 2512db270a8SFrederic Weisbecker * These two are not needed in ftrace as they are in the 2522db270a8SFrederic Weisbecker * generic trace_entry, filled by tracing_generic_entry_update, 2532db270a8SFrederic Weisbecker * but for the trace_event->bin() synthesizer benefit we do it 2542db270a8SFrederic Weisbecker * here too. 2552db270a8SFrederic Weisbecker */ 2562db270a8SFrederic Weisbecker t->cpu = cpu; 2572db270a8SFrederic Weisbecker t->pid = pid; 2582db270a8SFrederic Weisbecker 2592db270a8SFrederic Weisbecker t->sector = sector; 2602db270a8SFrederic Weisbecker t->bytes = bytes; 2612db270a8SFrederic Weisbecker t->action = what; 2622db270a8SFrederic Weisbecker t->device = bt->dev; 2632db270a8SFrederic Weisbecker t->error = error; 2642db270a8SFrederic Weisbecker t->pdu_len = pdu_len; 2652db270a8SFrederic Weisbecker 2662db270a8SFrederic Weisbecker if (pdu_len) 2672db270a8SFrederic Weisbecker memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); 2682db270a8SFrederic Weisbecker 26918cea459SLi Zefan if (blk_tracer) { 270e77405adSSteven Rostedt trace_buffer_unlock_commit(buffer, event, 0, pc); 2712db270a8SFrederic Weisbecker return; 2722db270a8SFrederic Weisbecker } 2732db270a8SFrederic Weisbecker } 2742db270a8SFrederic Weisbecker 2752db270a8SFrederic Weisbecker local_irq_restore(flags); 2762db270a8SFrederic Weisbecker } 2772db270a8SFrederic Weisbecker 2782db270a8SFrederic Weisbecker static struct dentry *blk_tree_root; 2792db270a8SFrederic Weisbecker static DEFINE_MUTEX(blk_tree_mutex); 2802db270a8SFrederic Weisbecker 281ad5dd549SLi Zefan static void blk_trace_free(struct blk_trace *bt) 2822db270a8SFrederic Weisbecker { 2832db270a8SFrederic Weisbecker debugfs_remove(bt->msg_file); 2842db270a8SFrederic Weisbecker debugfs_remove(bt->dropped_file); 2852db270a8SFrederic Weisbecker relay_close(bt->rchan); 28639cbb602SAlan D. Brunelle debugfs_remove(bt->dir); 2872db270a8SFrederic Weisbecker free_percpu(bt->sequence); 2882db270a8SFrederic Weisbecker free_percpu(bt->msg_data); 2892db270a8SFrederic Weisbecker kfree(bt); 290ad5dd549SLi Zefan } 291ad5dd549SLi Zefan 292ad5dd549SLi Zefan static void blk_trace_cleanup(struct blk_trace *bt) 293ad5dd549SLi Zefan { 294ad5dd549SLi Zefan blk_trace_free(bt); 2952db270a8SFrederic Weisbecker if (atomic_dec_and_test(&blk_probes_ref)) 2962db270a8SFrederic Weisbecker blk_unregister_tracepoints(); 2972db270a8SFrederic Weisbecker } 2982db270a8SFrederic Weisbecker 2992db270a8SFrederic Weisbecker int blk_trace_remove(struct request_queue *q) 3002db270a8SFrederic Weisbecker { 3012db270a8SFrederic Weisbecker struct blk_trace *bt; 3022db270a8SFrederic Weisbecker 3032db270a8SFrederic Weisbecker bt = xchg(&q->blk_trace, NULL); 3042db270a8SFrederic Weisbecker if (!bt) 3052db270a8SFrederic Weisbecker return -EINVAL; 3062db270a8SFrederic Weisbecker 30755547204SLi Zefan if (bt->trace_state != Blktrace_running) 3082db270a8SFrederic Weisbecker blk_trace_cleanup(bt); 3092db270a8SFrederic Weisbecker 3102db270a8SFrederic Weisbecker return 0; 3112db270a8SFrederic Weisbecker } 3122db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_remove); 3132db270a8SFrederic Weisbecker 3142db270a8SFrederic Weisbecker static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, 3152db270a8SFrederic Weisbecker size_t count, loff_t *ppos) 3162db270a8SFrederic Weisbecker { 3172db270a8SFrederic Weisbecker struct blk_trace *bt = filp->private_data; 3182db270a8SFrederic Weisbecker char buf[16]; 3192db270a8SFrederic Weisbecker 3202db270a8SFrederic Weisbecker snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); 3212db270a8SFrederic Weisbecker 3222db270a8SFrederic Weisbecker return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); 3232db270a8SFrederic Weisbecker } 3242db270a8SFrederic Weisbecker 3252db270a8SFrederic Weisbecker static const struct file_operations blk_dropped_fops = { 3262db270a8SFrederic Weisbecker .owner = THIS_MODULE, 327234e3405SStephen Boyd .open = simple_open, 3282db270a8SFrederic Weisbecker .read = blk_dropped_read, 3296038f373SArnd Bergmann .llseek = default_llseek, 3302db270a8SFrederic Weisbecker }; 3312db270a8SFrederic Weisbecker 3322db270a8SFrederic Weisbecker static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, 3332db270a8SFrederic Weisbecker size_t count, loff_t *ppos) 3342db270a8SFrederic Weisbecker { 3352db270a8SFrederic Weisbecker char *msg; 3362db270a8SFrederic Weisbecker struct blk_trace *bt; 3372db270a8SFrederic Weisbecker 3387635b03aSLi Zefan if (count >= BLK_TN_MAX_MSG) 3392db270a8SFrederic Weisbecker return -EINVAL; 3402db270a8SFrederic Weisbecker 341a4b3ada8SCarl Henrik Lunde msg = kmalloc(count + 1, GFP_KERNEL); 3422db270a8SFrederic Weisbecker if (msg == NULL) 3432db270a8SFrederic Weisbecker return -ENOMEM; 3442db270a8SFrederic Weisbecker 3452db270a8SFrederic Weisbecker if (copy_from_user(msg, buffer, count)) { 3462db270a8SFrederic Weisbecker kfree(msg); 3472db270a8SFrederic Weisbecker return -EFAULT; 3482db270a8SFrederic Weisbecker } 3492db270a8SFrederic Weisbecker 350a4b3ada8SCarl Henrik Lunde msg[count] = '\0'; 3512db270a8SFrederic Weisbecker bt = filp->private_data; 3522db270a8SFrederic Weisbecker __trace_note_message(bt, "%s", msg); 3532db270a8SFrederic Weisbecker kfree(msg); 3542db270a8SFrederic Weisbecker 3552db270a8SFrederic Weisbecker return count; 3562db270a8SFrederic Weisbecker } 3572db270a8SFrederic Weisbecker 3582db270a8SFrederic Weisbecker static const struct file_operations blk_msg_fops = { 3592db270a8SFrederic Weisbecker .owner = THIS_MODULE, 360234e3405SStephen Boyd .open = simple_open, 3612db270a8SFrederic Weisbecker .write = blk_msg_write, 3626038f373SArnd Bergmann .llseek = noop_llseek, 3632db270a8SFrederic Weisbecker }; 3642db270a8SFrederic Weisbecker 3652db270a8SFrederic Weisbecker /* 3662db270a8SFrederic Weisbecker * Keep track of how many times we encountered a full subbuffer, to aid 3672db270a8SFrederic Weisbecker * the user space app in telling how many lost events there were. 3682db270a8SFrederic Weisbecker */ 3692db270a8SFrederic Weisbecker static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, 3702db270a8SFrederic Weisbecker void *prev_subbuf, size_t prev_padding) 3712db270a8SFrederic Weisbecker { 3722db270a8SFrederic Weisbecker struct blk_trace *bt; 3732db270a8SFrederic Weisbecker 3742db270a8SFrederic Weisbecker if (!relay_buf_full(buf)) 3752db270a8SFrederic Weisbecker return 1; 3762db270a8SFrederic Weisbecker 3772db270a8SFrederic Weisbecker bt = buf->chan->private_data; 3782db270a8SFrederic Weisbecker atomic_inc(&bt->dropped); 3792db270a8SFrederic Weisbecker return 0; 3802db270a8SFrederic Weisbecker } 3812db270a8SFrederic Weisbecker 3822db270a8SFrederic Weisbecker static int blk_remove_buf_file_callback(struct dentry *dentry) 3832db270a8SFrederic Weisbecker { 3842db270a8SFrederic Weisbecker debugfs_remove(dentry); 3852db270a8SFrederic Weisbecker 3862db270a8SFrederic Weisbecker return 0; 3872db270a8SFrederic Weisbecker } 3882db270a8SFrederic Weisbecker 3892db270a8SFrederic Weisbecker static struct dentry *blk_create_buf_file_callback(const char *filename, 3902db270a8SFrederic Weisbecker struct dentry *parent, 391f4ae40a6SAl Viro umode_t mode, 3922db270a8SFrederic Weisbecker struct rchan_buf *buf, 3932db270a8SFrederic Weisbecker int *is_global) 3942db270a8SFrederic Weisbecker { 3952db270a8SFrederic Weisbecker return debugfs_create_file(filename, mode, parent, buf, 3962db270a8SFrederic Weisbecker &relay_file_operations); 3972db270a8SFrederic Weisbecker } 3982db270a8SFrederic Weisbecker 3992db270a8SFrederic Weisbecker static struct rchan_callbacks blk_relay_callbacks = { 4002db270a8SFrederic Weisbecker .subbuf_start = blk_subbuf_start_callback, 4012db270a8SFrederic Weisbecker .create_buf_file = blk_create_buf_file_callback, 4022db270a8SFrederic Weisbecker .remove_buf_file = blk_remove_buf_file_callback, 4032db270a8SFrederic Weisbecker }; 4042db270a8SFrederic Weisbecker 4059908c309SLi Zefan static void blk_trace_setup_lba(struct blk_trace *bt, 4069908c309SLi Zefan struct block_device *bdev) 4079908c309SLi Zefan { 4089908c309SLi Zefan struct hd_struct *part = NULL; 4099908c309SLi Zefan 4109908c309SLi Zefan if (bdev) 4119908c309SLi Zefan part = bdev->bd_part; 4129908c309SLi Zefan 4139908c309SLi Zefan if (part) { 4149908c309SLi Zefan bt->start_lba = part->start_sect; 4159908c309SLi Zefan bt->end_lba = part->start_sect + part->nr_sects; 4169908c309SLi Zefan } else { 4179908c309SLi Zefan bt->start_lba = 0; 4189908c309SLi Zefan bt->end_lba = -1ULL; 4199908c309SLi Zefan } 4209908c309SLi Zefan } 4219908c309SLi Zefan 4222db270a8SFrederic Weisbecker /* 4232db270a8SFrederic Weisbecker * Setup everything required to start tracing 4242db270a8SFrederic Weisbecker */ 4252db270a8SFrederic Weisbecker int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 426d0deef5bSShawn Du struct block_device *bdev, 4272db270a8SFrederic Weisbecker struct blk_user_trace_setup *buts) 4282db270a8SFrederic Weisbecker { 4292db270a8SFrederic Weisbecker struct blk_trace *old_bt, *bt = NULL; 4302db270a8SFrederic Weisbecker struct dentry *dir = NULL; 4312db270a8SFrederic Weisbecker int ret, i; 4322db270a8SFrederic Weisbecker 4332db270a8SFrederic Weisbecker if (!buts->buf_size || !buts->buf_nr) 4342db270a8SFrederic Weisbecker return -EINVAL; 4352db270a8SFrederic Weisbecker 4362db270a8SFrederic Weisbecker strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); 4372db270a8SFrederic Weisbecker buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; 4382db270a8SFrederic Weisbecker 4392db270a8SFrederic Weisbecker /* 4402db270a8SFrederic Weisbecker * some device names have larger paths - convert the slashes 4412db270a8SFrederic Weisbecker * to underscores for this to work as expected 4422db270a8SFrederic Weisbecker */ 4432db270a8SFrederic Weisbecker for (i = 0; i < strlen(buts->name); i++) 4442db270a8SFrederic Weisbecker if (buts->name[i] == '/') 4452db270a8SFrederic Weisbecker buts->name[i] = '_'; 4462db270a8SFrederic Weisbecker 4472db270a8SFrederic Weisbecker bt = kzalloc(sizeof(*bt), GFP_KERNEL); 4482db270a8SFrederic Weisbecker if (!bt) 449ad5dd549SLi Zefan return -ENOMEM; 4502db270a8SFrederic Weisbecker 451ad5dd549SLi Zefan ret = -ENOMEM; 4522db270a8SFrederic Weisbecker bt->sequence = alloc_percpu(unsigned long); 4532db270a8SFrederic Weisbecker if (!bt->sequence) 4542db270a8SFrederic Weisbecker goto err; 4552db270a8SFrederic Weisbecker 456f0ef0398SIngo Molnar bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); 4572db270a8SFrederic Weisbecker if (!bt->msg_data) 4582db270a8SFrederic Weisbecker goto err; 4592db270a8SFrederic Weisbecker 4602db270a8SFrederic Weisbecker ret = -ENOENT; 4612db270a8SFrederic Weisbecker 462b5230b56SLi Zefan mutex_lock(&blk_tree_mutex); 4632db270a8SFrederic Weisbecker if (!blk_tree_root) { 4642db270a8SFrederic Weisbecker blk_tree_root = debugfs_create_dir("block", NULL); 465b5230b56SLi Zefan if (!blk_tree_root) { 466b5230b56SLi Zefan mutex_unlock(&blk_tree_mutex); 4671a17662eSLi Zefan goto err; 4682db270a8SFrederic Weisbecker } 469b5230b56SLi Zefan } 470b5230b56SLi Zefan mutex_unlock(&blk_tree_mutex); 4712db270a8SFrederic Weisbecker 4722db270a8SFrederic Weisbecker dir = debugfs_create_dir(buts->name, blk_tree_root); 4732db270a8SFrederic Weisbecker 4742db270a8SFrederic Weisbecker if (!dir) 4752db270a8SFrederic Weisbecker goto err; 4762db270a8SFrederic Weisbecker 4772db270a8SFrederic Weisbecker bt->dir = dir; 4782db270a8SFrederic Weisbecker bt->dev = dev; 4792db270a8SFrederic Weisbecker atomic_set(&bt->dropped, 0); 4802db270a8SFrederic Weisbecker 4812db270a8SFrederic Weisbecker ret = -EIO; 4822db270a8SFrederic Weisbecker bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, 4832db270a8SFrederic Weisbecker &blk_dropped_fops); 4842db270a8SFrederic Weisbecker if (!bt->dropped_file) 4852db270a8SFrederic Weisbecker goto err; 4862db270a8SFrederic Weisbecker 4872db270a8SFrederic Weisbecker bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); 4882db270a8SFrederic Weisbecker if (!bt->msg_file) 4892db270a8SFrederic Weisbecker goto err; 4902db270a8SFrederic Weisbecker 4912db270a8SFrederic Weisbecker bt->rchan = relay_open("trace", dir, buts->buf_size, 4922db270a8SFrederic Weisbecker buts->buf_nr, &blk_relay_callbacks, bt); 4932db270a8SFrederic Weisbecker if (!bt->rchan) 4942db270a8SFrederic Weisbecker goto err; 4952db270a8SFrederic Weisbecker 4962db270a8SFrederic Weisbecker bt->act_mask = buts->act_mask; 4972db270a8SFrederic Weisbecker if (!bt->act_mask) 4982db270a8SFrederic Weisbecker bt->act_mask = (u16) -1; 4992db270a8SFrederic Weisbecker 5009908c309SLi Zefan blk_trace_setup_lba(bt, bdev); 5012db270a8SFrederic Weisbecker 502d0deef5bSShawn Du /* overwrite with user settings */ 503d0deef5bSShawn Du if (buts->start_lba) 504d0deef5bSShawn Du bt->start_lba = buts->start_lba; 505d0deef5bSShawn Du if (buts->end_lba) 506d0deef5bSShawn Du bt->end_lba = buts->end_lba; 507d0deef5bSShawn Du 5082db270a8SFrederic Weisbecker bt->pid = buts->pid; 5092db270a8SFrederic Weisbecker bt->trace_state = Blktrace_setup; 5102db270a8SFrederic Weisbecker 5112db270a8SFrederic Weisbecker ret = -EBUSY; 5122db270a8SFrederic Weisbecker old_bt = xchg(&q->blk_trace, bt); 5132db270a8SFrederic Weisbecker if (old_bt) { 5142db270a8SFrederic Weisbecker (void) xchg(&q->blk_trace, old_bt); 5152db270a8SFrederic Weisbecker goto err; 5162db270a8SFrederic Weisbecker } 5172db270a8SFrederic Weisbecker 51817ba97e3SLi Zefan if (atomic_inc_return(&blk_probes_ref) == 1) 519cbe28296SLi Zefan blk_register_tracepoints(); 520cbe28296SLi Zefan 5212db270a8SFrederic Weisbecker return 0; 5222db270a8SFrederic Weisbecker err: 523ad5dd549SLi Zefan blk_trace_free(bt); 5242db270a8SFrederic Weisbecker return ret; 5252db270a8SFrederic Weisbecker } 5262db270a8SFrederic Weisbecker 5272db270a8SFrederic Weisbecker int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 528d0deef5bSShawn Du struct block_device *bdev, 5292db270a8SFrederic Weisbecker char __user *arg) 5302db270a8SFrederic Weisbecker { 5312db270a8SFrederic Weisbecker struct blk_user_trace_setup buts; 5322db270a8SFrederic Weisbecker int ret; 5332db270a8SFrederic Weisbecker 5342db270a8SFrederic Weisbecker ret = copy_from_user(&buts, arg, sizeof(buts)); 5352db270a8SFrederic Weisbecker if (ret) 5362db270a8SFrederic Weisbecker return -EFAULT; 5372db270a8SFrederic Weisbecker 538d0deef5bSShawn Du ret = do_blk_trace_setup(q, name, dev, bdev, &buts); 5392db270a8SFrederic Weisbecker if (ret) 5402db270a8SFrederic Weisbecker return ret; 5412db270a8SFrederic Weisbecker 5429a8c28c8SDmitry Monakhov if (copy_to_user(arg, &buts, sizeof(buts))) { 5439a8c28c8SDmitry Monakhov blk_trace_remove(q); 5442db270a8SFrederic Weisbecker return -EFAULT; 5459a8c28c8SDmitry Monakhov } 5462db270a8SFrederic Weisbecker return 0; 5472db270a8SFrederic Weisbecker } 5482db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_setup); 5492db270a8SFrederic Weisbecker 55062c2a7d9SArnd Bergmann #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) 55162c2a7d9SArnd Bergmann static int compat_blk_trace_setup(struct request_queue *q, char *name, 55262c2a7d9SArnd Bergmann dev_t dev, struct block_device *bdev, 55362c2a7d9SArnd Bergmann char __user *arg) 55462c2a7d9SArnd Bergmann { 55562c2a7d9SArnd Bergmann struct blk_user_trace_setup buts; 55662c2a7d9SArnd Bergmann struct compat_blk_user_trace_setup cbuts; 55762c2a7d9SArnd Bergmann int ret; 55862c2a7d9SArnd Bergmann 55962c2a7d9SArnd Bergmann if (copy_from_user(&cbuts, arg, sizeof(cbuts))) 56062c2a7d9SArnd Bergmann return -EFAULT; 56162c2a7d9SArnd Bergmann 56262c2a7d9SArnd Bergmann buts = (struct blk_user_trace_setup) { 56362c2a7d9SArnd Bergmann .act_mask = cbuts.act_mask, 56462c2a7d9SArnd Bergmann .buf_size = cbuts.buf_size, 56562c2a7d9SArnd Bergmann .buf_nr = cbuts.buf_nr, 56662c2a7d9SArnd Bergmann .start_lba = cbuts.start_lba, 56762c2a7d9SArnd Bergmann .end_lba = cbuts.end_lba, 56862c2a7d9SArnd Bergmann .pid = cbuts.pid, 56962c2a7d9SArnd Bergmann }; 57062c2a7d9SArnd Bergmann memcpy(&buts.name, &cbuts.name, 32); 57162c2a7d9SArnd Bergmann 57262c2a7d9SArnd Bergmann ret = do_blk_trace_setup(q, name, dev, bdev, &buts); 57362c2a7d9SArnd Bergmann if (ret) 57462c2a7d9SArnd Bergmann return ret; 57562c2a7d9SArnd Bergmann 57662c2a7d9SArnd Bergmann if (copy_to_user(arg, &buts.name, 32)) { 57762c2a7d9SArnd Bergmann blk_trace_remove(q); 57862c2a7d9SArnd Bergmann return -EFAULT; 57962c2a7d9SArnd Bergmann } 58062c2a7d9SArnd Bergmann 58162c2a7d9SArnd Bergmann return 0; 58262c2a7d9SArnd Bergmann } 58362c2a7d9SArnd Bergmann #endif 58462c2a7d9SArnd Bergmann 5852db270a8SFrederic Weisbecker int blk_trace_startstop(struct request_queue *q, int start) 5862db270a8SFrederic Weisbecker { 5872db270a8SFrederic Weisbecker int ret; 5882db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 5892db270a8SFrederic Weisbecker 5902db270a8SFrederic Weisbecker if (bt == NULL) 5912db270a8SFrederic Weisbecker return -EINVAL; 5922db270a8SFrederic Weisbecker 5932db270a8SFrederic Weisbecker /* 5942db270a8SFrederic Weisbecker * For starting a trace, we can transition from a setup or stopped 5952db270a8SFrederic Weisbecker * trace. For stopping a trace, the state must be running 5962db270a8SFrederic Weisbecker */ 5972db270a8SFrederic Weisbecker ret = -EINVAL; 5982db270a8SFrederic Weisbecker if (start) { 5992db270a8SFrederic Weisbecker if (bt->trace_state == Blktrace_setup || 6002db270a8SFrederic Weisbecker bt->trace_state == Blktrace_stopped) { 6012db270a8SFrederic Weisbecker blktrace_seq++; 6022db270a8SFrederic Weisbecker smp_mb(); 6032db270a8SFrederic Weisbecker bt->trace_state = Blktrace_running; 6042db270a8SFrederic Weisbecker 6052db270a8SFrederic Weisbecker trace_note_time(bt); 6062db270a8SFrederic Weisbecker ret = 0; 6072db270a8SFrederic Weisbecker } 6082db270a8SFrederic Weisbecker } else { 6092db270a8SFrederic Weisbecker if (bt->trace_state == Blktrace_running) { 6102db270a8SFrederic Weisbecker bt->trace_state = Blktrace_stopped; 6112db270a8SFrederic Weisbecker relay_flush(bt->rchan); 6122db270a8SFrederic Weisbecker ret = 0; 6132db270a8SFrederic Weisbecker } 6142db270a8SFrederic Weisbecker } 6152db270a8SFrederic Weisbecker 6162db270a8SFrederic Weisbecker return ret; 6172db270a8SFrederic Weisbecker } 6182db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_startstop); 6192db270a8SFrederic Weisbecker 6202db270a8SFrederic Weisbecker /** 6212db270a8SFrederic Weisbecker * blk_trace_ioctl: - handle the ioctls associated with tracing 6222db270a8SFrederic Weisbecker * @bdev: the block device 6232db270a8SFrederic Weisbecker * @cmd: the ioctl cmd 6242db270a8SFrederic Weisbecker * @arg: the argument data, if any 6252db270a8SFrederic Weisbecker * 6262db270a8SFrederic Weisbecker **/ 6272db270a8SFrederic Weisbecker int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) 6282db270a8SFrederic Weisbecker { 6292db270a8SFrederic Weisbecker struct request_queue *q; 6302db270a8SFrederic Weisbecker int ret, start = 0; 6312db270a8SFrederic Weisbecker char b[BDEVNAME_SIZE]; 6322db270a8SFrederic Weisbecker 6332db270a8SFrederic Weisbecker q = bdev_get_queue(bdev); 6342db270a8SFrederic Weisbecker if (!q) 6352db270a8SFrederic Weisbecker return -ENXIO; 6362db270a8SFrederic Weisbecker 6372db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 6382db270a8SFrederic Weisbecker 6392db270a8SFrederic Weisbecker switch (cmd) { 6402db270a8SFrederic Weisbecker case BLKTRACESETUP: 6412db270a8SFrederic Weisbecker bdevname(bdev, b); 642d0deef5bSShawn Du ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); 6432db270a8SFrederic Weisbecker break; 64462c2a7d9SArnd Bergmann #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) 64562c2a7d9SArnd Bergmann case BLKTRACESETUP32: 64662c2a7d9SArnd Bergmann bdevname(bdev, b); 64762c2a7d9SArnd Bergmann ret = compat_blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); 64862c2a7d9SArnd Bergmann break; 64962c2a7d9SArnd Bergmann #endif 6502db270a8SFrederic Weisbecker case BLKTRACESTART: 6512db270a8SFrederic Weisbecker start = 1; 6522db270a8SFrederic Weisbecker case BLKTRACESTOP: 6532db270a8SFrederic Weisbecker ret = blk_trace_startstop(q, start); 6542db270a8SFrederic Weisbecker break; 6552db270a8SFrederic Weisbecker case BLKTRACETEARDOWN: 6562db270a8SFrederic Weisbecker ret = blk_trace_remove(q); 6572db270a8SFrederic Weisbecker break; 6582db270a8SFrederic Weisbecker default: 6592db270a8SFrederic Weisbecker ret = -ENOTTY; 6602db270a8SFrederic Weisbecker break; 6612db270a8SFrederic Weisbecker } 6622db270a8SFrederic Weisbecker 6632db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 6642db270a8SFrederic Weisbecker return ret; 6652db270a8SFrederic Weisbecker } 6662db270a8SFrederic Weisbecker 6672db270a8SFrederic Weisbecker /** 6682db270a8SFrederic Weisbecker * blk_trace_shutdown: - stop and cleanup trace structures 6692db270a8SFrederic Weisbecker * @q: the request queue associated with the device 6702db270a8SFrederic Weisbecker * 6712db270a8SFrederic Weisbecker **/ 6722db270a8SFrederic Weisbecker void blk_trace_shutdown(struct request_queue *q) 6732db270a8SFrederic Weisbecker { 6742db270a8SFrederic Weisbecker if (q->blk_trace) { 6752db270a8SFrederic Weisbecker blk_trace_startstop(q, 0); 6762db270a8SFrederic Weisbecker blk_trace_remove(q); 6772db270a8SFrederic Weisbecker } 6782db270a8SFrederic Weisbecker } 6792db270a8SFrederic Weisbecker 6802db270a8SFrederic Weisbecker /* 6812db270a8SFrederic Weisbecker * blktrace probes 6822db270a8SFrederic Weisbecker */ 6832db270a8SFrederic Weisbecker 6842db270a8SFrederic Weisbecker /** 6852db270a8SFrederic Weisbecker * blk_add_trace_rq - Add a trace for a request oriented action 6862db270a8SFrederic Weisbecker * @q: queue the io is for 6872db270a8SFrederic Weisbecker * @rq: the source request 6882db270a8SFrederic Weisbecker * @what: the action 6892db270a8SFrederic Weisbecker * 6902db270a8SFrederic Weisbecker * Description: 6912db270a8SFrederic Weisbecker * Records an action against a request. Will log the bio offset + size. 6922db270a8SFrederic Weisbecker * 6932db270a8SFrederic Weisbecker **/ 6942db270a8SFrederic Weisbecker static void blk_add_trace_rq(struct request_queue *q, struct request *rq, 6952db270a8SFrederic Weisbecker u32 what) 6962db270a8SFrederic Weisbecker { 6972db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 6982db270a8SFrederic Weisbecker 6992db270a8SFrederic Weisbecker if (likely(!bt)) 7002db270a8SFrederic Weisbecker return; 7012db270a8SFrederic Weisbecker 70233659ebbSChristoph Hellwig if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { 7032db270a8SFrederic Weisbecker what |= BLK_TC_ACT(BLK_TC_PC); 704805f6b5eSTao Ma __blk_add_trace(bt, 0, blk_rq_bytes(rq), rq->cmd_flags, 7052e46e8b2STejun Heo what, rq->errors, rq->cmd_len, rq->cmd); 7062db270a8SFrederic Weisbecker } else { 7072db270a8SFrederic Weisbecker what |= BLK_TC_ACT(BLK_TC_FS); 708805f6b5eSTao Ma __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 709805f6b5eSTao Ma rq->cmd_flags, what, rq->errors, 0, NULL); 7102db270a8SFrederic Weisbecker } 7112db270a8SFrederic Weisbecker } 7122db270a8SFrederic Weisbecker 71338516ab5SSteven Rostedt static void blk_add_trace_rq_abort(void *ignore, 71438516ab5SSteven Rostedt struct request_queue *q, struct request *rq) 7152db270a8SFrederic Weisbecker { 7162db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_ABORT); 7172db270a8SFrederic Weisbecker } 7182db270a8SFrederic Weisbecker 71938516ab5SSteven Rostedt static void blk_add_trace_rq_insert(void *ignore, 72038516ab5SSteven Rostedt struct request_queue *q, struct request *rq) 7212db270a8SFrederic Weisbecker { 7222db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_INSERT); 7232db270a8SFrederic Weisbecker } 7242db270a8SFrederic Weisbecker 72538516ab5SSteven Rostedt static void blk_add_trace_rq_issue(void *ignore, 72638516ab5SSteven Rostedt struct request_queue *q, struct request *rq) 7272db270a8SFrederic Weisbecker { 7282db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_ISSUE); 7292db270a8SFrederic Weisbecker } 7302db270a8SFrederic Weisbecker 73138516ab5SSteven Rostedt static void blk_add_trace_rq_requeue(void *ignore, 73238516ab5SSteven Rostedt struct request_queue *q, 7332db270a8SFrederic Weisbecker struct request *rq) 7342db270a8SFrederic Weisbecker { 7352db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); 7362db270a8SFrederic Weisbecker } 7372db270a8SFrederic Weisbecker 73838516ab5SSteven Rostedt static void blk_add_trace_rq_complete(void *ignore, 73938516ab5SSteven Rostedt struct request_queue *q, 7402db270a8SFrederic Weisbecker struct request *rq) 7412db270a8SFrederic Weisbecker { 7423a366e61STejun Heo struct blk_trace *bt = q->blk_trace; 7433a366e61STejun Heo 7443a366e61STejun Heo /* if control ever passes through here, it's a request based driver */ 7453a366e61STejun Heo if (unlikely(bt && !bt->rq_based)) 7463a366e61STejun Heo bt->rq_based = true; 7473a366e61STejun Heo 7482db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); 7492db270a8SFrederic Weisbecker } 7502db270a8SFrederic Weisbecker 7512db270a8SFrederic Weisbecker /** 7522db270a8SFrederic Weisbecker * blk_add_trace_bio - Add a trace for a bio oriented action 7532db270a8SFrederic Weisbecker * @q: queue the io is for 7542db270a8SFrederic Weisbecker * @bio: the source bio 7552db270a8SFrederic Weisbecker * @what: the action 756797a455dSJens Axboe * @error: error, if any 7572db270a8SFrederic Weisbecker * 7582db270a8SFrederic Weisbecker * Description: 7592db270a8SFrederic Weisbecker * Records an action against a bio. Will log the bio offset + size. 7602db270a8SFrederic Weisbecker * 7612db270a8SFrederic Weisbecker **/ 7622db270a8SFrederic Weisbecker static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, 763797a455dSJens Axboe u32 what, int error) 7642db270a8SFrederic Weisbecker { 7652db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7662db270a8SFrederic Weisbecker 7672db270a8SFrederic Weisbecker if (likely(!bt)) 7682db270a8SFrederic Weisbecker return; 7692db270a8SFrederic Weisbecker 770797a455dSJens Axboe if (!error && !bio_flagged(bio, BIO_UPTODATE)) 771797a455dSJens Axboe error = EIO; 772797a455dSJens Axboe 7732db270a8SFrederic Weisbecker __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, 774797a455dSJens Axboe error, 0, NULL); 7752db270a8SFrederic Weisbecker } 7762db270a8SFrederic Weisbecker 77738516ab5SSteven Rostedt static void blk_add_trace_bio_bounce(void *ignore, 77838516ab5SSteven Rostedt struct request_queue *q, struct bio *bio) 7792db270a8SFrederic Weisbecker { 780797a455dSJens Axboe blk_add_trace_bio(q, bio, BLK_TA_BOUNCE, 0); 7812db270a8SFrederic Weisbecker } 7822db270a8SFrederic Weisbecker 7833a366e61STejun Heo static void blk_add_trace_bio_complete(void *ignore, struct bio *bio, int error) 7842db270a8SFrederic Weisbecker { 7853a366e61STejun Heo struct request_queue *q; 7863a366e61STejun Heo struct blk_trace *bt; 7873a366e61STejun Heo 7883a366e61STejun Heo if (!bio->bi_bdev) 7893a366e61STejun Heo return; 7903a366e61STejun Heo 7913a366e61STejun Heo q = bdev_get_queue(bio->bi_bdev); 7923a366e61STejun Heo bt = q->blk_trace; 7933a366e61STejun Heo 7943a366e61STejun Heo /* 7953a366e61STejun Heo * Request based drivers will generate both rq and bio completions. 7963a366e61STejun Heo * Ignore bio ones. 7973a366e61STejun Heo */ 7983a366e61STejun Heo if (likely(!bt) || bt->rq_based) 7993a366e61STejun Heo return; 8003a366e61STejun Heo 801797a455dSJens Axboe blk_add_trace_bio(q, bio, BLK_TA_COMPLETE, error); 8022db270a8SFrederic Weisbecker } 8032db270a8SFrederic Weisbecker 80438516ab5SSteven Rostedt static void blk_add_trace_bio_backmerge(void *ignore, 80538516ab5SSteven Rostedt struct request_queue *q, 8068c1cf6bbSTejun Heo struct request *rq, 8072db270a8SFrederic Weisbecker struct bio *bio) 8082db270a8SFrederic Weisbecker { 809797a455dSJens Axboe blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE, 0); 8102db270a8SFrederic Weisbecker } 8112db270a8SFrederic Weisbecker 81238516ab5SSteven Rostedt static void blk_add_trace_bio_frontmerge(void *ignore, 81338516ab5SSteven Rostedt struct request_queue *q, 8148c1cf6bbSTejun Heo struct request *rq, 8152db270a8SFrederic Weisbecker struct bio *bio) 8162db270a8SFrederic Weisbecker { 817797a455dSJens Axboe blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE, 0); 8182db270a8SFrederic Weisbecker } 8192db270a8SFrederic Weisbecker 82038516ab5SSteven Rostedt static void blk_add_trace_bio_queue(void *ignore, 82138516ab5SSteven Rostedt struct request_queue *q, struct bio *bio) 8222db270a8SFrederic Weisbecker { 823797a455dSJens Axboe blk_add_trace_bio(q, bio, BLK_TA_QUEUE, 0); 8242db270a8SFrederic Weisbecker } 8252db270a8SFrederic Weisbecker 82638516ab5SSteven Rostedt static void blk_add_trace_getrq(void *ignore, 82738516ab5SSteven Rostedt struct request_queue *q, 8282db270a8SFrederic Weisbecker struct bio *bio, int rw) 8292db270a8SFrederic Weisbecker { 8302db270a8SFrederic Weisbecker if (bio) 831797a455dSJens Axboe blk_add_trace_bio(q, bio, BLK_TA_GETRQ, 0); 8322db270a8SFrederic Weisbecker else { 8332db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8342db270a8SFrederic Weisbecker 8352db270a8SFrederic Weisbecker if (bt) 8362db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); 8372db270a8SFrederic Weisbecker } 8382db270a8SFrederic Weisbecker } 8392db270a8SFrederic Weisbecker 8402db270a8SFrederic Weisbecker 84138516ab5SSteven Rostedt static void blk_add_trace_sleeprq(void *ignore, 84238516ab5SSteven Rostedt struct request_queue *q, 8432db270a8SFrederic Weisbecker struct bio *bio, int rw) 8442db270a8SFrederic Weisbecker { 8452db270a8SFrederic Weisbecker if (bio) 846797a455dSJens Axboe blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ, 0); 8472db270a8SFrederic Weisbecker else { 8482db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8492db270a8SFrederic Weisbecker 8502db270a8SFrederic Weisbecker if (bt) 8512db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, 8522db270a8SFrederic Weisbecker 0, 0, NULL); 8532db270a8SFrederic Weisbecker } 8542db270a8SFrederic Weisbecker } 8552db270a8SFrederic Weisbecker 85638516ab5SSteven Rostedt static void blk_add_trace_plug(void *ignore, struct request_queue *q) 8572db270a8SFrederic Weisbecker { 8582db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8592db270a8SFrederic Weisbecker 8602db270a8SFrederic Weisbecker if (bt) 8612db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); 8622db270a8SFrederic Weisbecker } 8632db270a8SFrederic Weisbecker 86449cac01eSJens Axboe static void blk_add_trace_unplug(void *ignore, struct request_queue *q, 86549cac01eSJens Axboe unsigned int depth, bool explicit) 8662db270a8SFrederic Weisbecker { 8672db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8682db270a8SFrederic Weisbecker 8692db270a8SFrederic Weisbecker if (bt) { 87094b5eb28SJens Axboe __be64 rpdu = cpu_to_be64(depth); 87149cac01eSJens Axboe u32 what; 8722db270a8SFrederic Weisbecker 87349cac01eSJens Axboe if (explicit) 87449cac01eSJens Axboe what = BLK_TA_UNPLUG_IO; 87549cac01eSJens Axboe else 87649cac01eSJens Axboe what = BLK_TA_UNPLUG_TIMER; 87749cac01eSJens Axboe 87849cac01eSJens Axboe __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); 8792db270a8SFrederic Weisbecker } 8802db270a8SFrederic Weisbecker } 8812db270a8SFrederic Weisbecker 88238516ab5SSteven Rostedt static void blk_add_trace_split(void *ignore, 88338516ab5SSteven Rostedt struct request_queue *q, struct bio *bio, 8842db270a8SFrederic Weisbecker unsigned int pdu) 8852db270a8SFrederic Weisbecker { 8862db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8872db270a8SFrederic Weisbecker 8882db270a8SFrederic Weisbecker if (bt) { 8892db270a8SFrederic Weisbecker __be64 rpdu = cpu_to_be64(pdu); 8902db270a8SFrederic Weisbecker 8912db270a8SFrederic Weisbecker __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, 8922db270a8SFrederic Weisbecker BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), 8932db270a8SFrederic Weisbecker sizeof(rpdu), &rpdu); 8942db270a8SFrederic Weisbecker } 8952db270a8SFrederic Weisbecker } 8962db270a8SFrederic Weisbecker 8972db270a8SFrederic Weisbecker /** 898d07335e5SMike Snitzer * blk_add_trace_bio_remap - Add a trace for a bio-remap operation 899546cf44aSRandy Dunlap * @ignore: trace callback data parameter (not used) 9002db270a8SFrederic Weisbecker * @q: queue the io is for 9012db270a8SFrederic Weisbecker * @bio: the source bio 9022db270a8SFrederic Weisbecker * @dev: target device 903a42aaa3bSAlan D. Brunelle * @from: source sector 9042db270a8SFrederic Weisbecker * 9052db270a8SFrederic Weisbecker * Description: 9062db270a8SFrederic Weisbecker * Device mapper or raid target sometimes need to split a bio because 9072db270a8SFrederic Weisbecker * it spans a stripe (or similar). Add a trace for that action. 9082db270a8SFrederic Weisbecker * 9092db270a8SFrederic Weisbecker **/ 910d07335e5SMike Snitzer static void blk_add_trace_bio_remap(void *ignore, 91138516ab5SSteven Rostedt struct request_queue *q, struct bio *bio, 91222a7c31aSAlan D. Brunelle dev_t dev, sector_t from) 9132db270a8SFrederic Weisbecker { 9142db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 9152db270a8SFrederic Weisbecker struct blk_io_trace_remap r; 9162db270a8SFrederic Weisbecker 9172db270a8SFrederic Weisbecker if (likely(!bt)) 9182db270a8SFrederic Weisbecker return; 9192db270a8SFrederic Weisbecker 920a42aaa3bSAlan D. Brunelle r.device_from = cpu_to_be32(dev); 921a42aaa3bSAlan D. Brunelle r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); 922a42aaa3bSAlan D. Brunelle r.sector_from = cpu_to_be64(from); 9232db270a8SFrederic Weisbecker 92422a7c31aSAlan D. Brunelle __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, 92522a7c31aSAlan D. Brunelle BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), 92622a7c31aSAlan D. Brunelle sizeof(r), &r); 9272db270a8SFrederic Weisbecker } 9282db270a8SFrederic Weisbecker 9292db270a8SFrederic Weisbecker /** 930b0da3f0dSJun'ichi Nomura * blk_add_trace_rq_remap - Add a trace for a request-remap operation 931546cf44aSRandy Dunlap * @ignore: trace callback data parameter (not used) 932b0da3f0dSJun'ichi Nomura * @q: queue the io is for 933b0da3f0dSJun'ichi Nomura * @rq: the source request 934b0da3f0dSJun'ichi Nomura * @dev: target device 935b0da3f0dSJun'ichi Nomura * @from: source sector 936b0da3f0dSJun'ichi Nomura * 937b0da3f0dSJun'ichi Nomura * Description: 938b0da3f0dSJun'ichi Nomura * Device mapper remaps request to other devices. 939b0da3f0dSJun'ichi Nomura * Add a trace for that action. 940b0da3f0dSJun'ichi Nomura * 941b0da3f0dSJun'ichi Nomura **/ 94238516ab5SSteven Rostedt static void blk_add_trace_rq_remap(void *ignore, 94338516ab5SSteven Rostedt struct request_queue *q, 944b0da3f0dSJun'ichi Nomura struct request *rq, dev_t dev, 945b0da3f0dSJun'ichi Nomura sector_t from) 946b0da3f0dSJun'ichi Nomura { 947b0da3f0dSJun'ichi Nomura struct blk_trace *bt = q->blk_trace; 948b0da3f0dSJun'ichi Nomura struct blk_io_trace_remap r; 949b0da3f0dSJun'ichi Nomura 950b0da3f0dSJun'ichi Nomura if (likely(!bt)) 951b0da3f0dSJun'ichi Nomura return; 952b0da3f0dSJun'ichi Nomura 953b0da3f0dSJun'ichi Nomura r.device_from = cpu_to_be32(dev); 954b0da3f0dSJun'ichi Nomura r.device_to = cpu_to_be32(disk_devt(rq->rq_disk)); 955b0da3f0dSJun'ichi Nomura r.sector_from = cpu_to_be64(from); 956b0da3f0dSJun'ichi Nomura 957b0da3f0dSJun'ichi Nomura __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 958b0da3f0dSJun'ichi Nomura rq_data_dir(rq), BLK_TA_REMAP, !!rq->errors, 959b0da3f0dSJun'ichi Nomura sizeof(r), &r); 960b0da3f0dSJun'ichi Nomura } 961b0da3f0dSJun'ichi Nomura 962b0da3f0dSJun'ichi Nomura /** 9632db270a8SFrederic Weisbecker * blk_add_driver_data - Add binary message with driver-specific data 9642db270a8SFrederic Weisbecker * @q: queue the io is for 9652db270a8SFrederic Weisbecker * @rq: io request 9662db270a8SFrederic Weisbecker * @data: driver-specific data 9672db270a8SFrederic Weisbecker * @len: length of driver-specific data 9682db270a8SFrederic Weisbecker * 9692db270a8SFrederic Weisbecker * Description: 9702db270a8SFrederic Weisbecker * Some drivers might want to write driver-specific data per request. 9712db270a8SFrederic Weisbecker * 9722db270a8SFrederic Weisbecker **/ 9732db270a8SFrederic Weisbecker void blk_add_driver_data(struct request_queue *q, 9742db270a8SFrederic Weisbecker struct request *rq, 9752db270a8SFrederic Weisbecker void *data, size_t len) 9762db270a8SFrederic Weisbecker { 9772db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 9782db270a8SFrederic Weisbecker 9792db270a8SFrederic Weisbecker if (likely(!bt)) 9802db270a8SFrederic Weisbecker return; 9812db270a8SFrederic Weisbecker 98233659ebbSChristoph Hellwig if (rq->cmd_type == REQ_TYPE_BLOCK_PC) 9832e46e8b2STejun Heo __blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, 9842e46e8b2STejun Heo BLK_TA_DRV_DATA, rq->errors, len, data); 9852db270a8SFrederic Weisbecker else 9862e46e8b2STejun Heo __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0, 9872e46e8b2STejun Heo BLK_TA_DRV_DATA, rq->errors, len, data); 9882db270a8SFrederic Weisbecker } 9892db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_add_driver_data); 9902db270a8SFrederic Weisbecker 9913c289ba7SLi Zefan static void blk_register_tracepoints(void) 9922db270a8SFrederic Weisbecker { 9932db270a8SFrederic Weisbecker int ret; 9942db270a8SFrederic Weisbecker 99538516ab5SSteven Rostedt ret = register_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); 9962db270a8SFrederic Weisbecker WARN_ON(ret); 99738516ab5SSteven Rostedt ret = register_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); 9982db270a8SFrederic Weisbecker WARN_ON(ret); 99938516ab5SSteven Rostedt ret = register_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); 10002db270a8SFrederic Weisbecker WARN_ON(ret); 100138516ab5SSteven Rostedt ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); 10022db270a8SFrederic Weisbecker WARN_ON(ret); 100338516ab5SSteven Rostedt ret = register_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); 10042db270a8SFrederic Weisbecker WARN_ON(ret); 100538516ab5SSteven Rostedt ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); 10062db270a8SFrederic Weisbecker WARN_ON(ret); 100738516ab5SSteven Rostedt ret = register_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); 10082db270a8SFrederic Weisbecker WARN_ON(ret); 100938516ab5SSteven Rostedt ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); 10102db270a8SFrederic Weisbecker WARN_ON(ret); 101138516ab5SSteven Rostedt ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); 10122db270a8SFrederic Weisbecker WARN_ON(ret); 101338516ab5SSteven Rostedt ret = register_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); 10142db270a8SFrederic Weisbecker WARN_ON(ret); 101538516ab5SSteven Rostedt ret = register_trace_block_getrq(blk_add_trace_getrq, NULL); 10162db270a8SFrederic Weisbecker WARN_ON(ret); 101738516ab5SSteven Rostedt ret = register_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); 10182db270a8SFrederic Weisbecker WARN_ON(ret); 101938516ab5SSteven Rostedt ret = register_trace_block_plug(blk_add_trace_plug, NULL); 10202db270a8SFrederic Weisbecker WARN_ON(ret); 102149cac01eSJens Axboe ret = register_trace_block_unplug(blk_add_trace_unplug, NULL); 10222db270a8SFrederic Weisbecker WARN_ON(ret); 102338516ab5SSteven Rostedt ret = register_trace_block_split(blk_add_trace_split, NULL); 10242db270a8SFrederic Weisbecker WARN_ON(ret); 1025d07335e5SMike Snitzer ret = register_trace_block_bio_remap(blk_add_trace_bio_remap, NULL); 10262db270a8SFrederic Weisbecker WARN_ON(ret); 102738516ab5SSteven Rostedt ret = register_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); 1028b0da3f0dSJun'ichi Nomura WARN_ON(ret); 10292db270a8SFrederic Weisbecker } 10302db270a8SFrederic Weisbecker 10312db270a8SFrederic Weisbecker static void blk_unregister_tracepoints(void) 10322db270a8SFrederic Weisbecker { 103338516ab5SSteven Rostedt unregister_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); 1034d07335e5SMike Snitzer unregister_trace_block_bio_remap(blk_add_trace_bio_remap, NULL); 103538516ab5SSteven Rostedt unregister_trace_block_split(blk_add_trace_split, NULL); 103649cac01eSJens Axboe unregister_trace_block_unplug(blk_add_trace_unplug, NULL); 103738516ab5SSteven Rostedt unregister_trace_block_plug(blk_add_trace_plug, NULL); 103838516ab5SSteven Rostedt unregister_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); 103938516ab5SSteven Rostedt unregister_trace_block_getrq(blk_add_trace_getrq, NULL); 104038516ab5SSteven Rostedt unregister_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); 104138516ab5SSteven Rostedt unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); 104238516ab5SSteven Rostedt unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); 104338516ab5SSteven Rostedt unregister_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); 104438516ab5SSteven Rostedt unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); 104538516ab5SSteven Rostedt unregister_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); 104638516ab5SSteven Rostedt unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); 104738516ab5SSteven Rostedt unregister_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); 104838516ab5SSteven Rostedt unregister_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); 104938516ab5SSteven Rostedt unregister_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); 10502db270a8SFrederic Weisbecker 10512db270a8SFrederic Weisbecker tracepoint_synchronize_unregister(); 10522db270a8SFrederic Weisbecker } 10532db270a8SFrederic Weisbecker 10542db270a8SFrederic Weisbecker /* 10552db270a8SFrederic Weisbecker * struct blk_io_tracer formatting routines 10562db270a8SFrederic Weisbecker */ 10572db270a8SFrederic Weisbecker 10582db270a8SFrederic Weisbecker static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) 10592db270a8SFrederic Weisbecker { 10602db270a8SFrederic Weisbecker int i = 0; 106165796348SLi Zefan int tc = t->action >> BLK_TC_SHIFT; 10622db270a8SFrederic Weisbecker 106318cea459SLi Zefan if (t->action == BLK_TN_MESSAGE) { 106418cea459SLi Zefan rwbs[i++] = 'N'; 106518cea459SLi Zefan goto out; 106618cea459SLi Zefan } 106718cea459SLi Zefan 1068c09c47caSNamhyung Kim if (tc & BLK_TC_FLUSH) 1069c09c47caSNamhyung Kim rwbs[i++] = 'F'; 1070c09c47caSNamhyung Kim 107165796348SLi Zefan if (tc & BLK_TC_DISCARD) 10722db270a8SFrederic Weisbecker rwbs[i++] = 'D'; 107365796348SLi Zefan else if (tc & BLK_TC_WRITE) 10742db270a8SFrederic Weisbecker rwbs[i++] = 'W'; 10752db270a8SFrederic Weisbecker else if (t->bytes) 10762db270a8SFrederic Weisbecker rwbs[i++] = 'R'; 10772db270a8SFrederic Weisbecker else 10782db270a8SFrederic Weisbecker rwbs[i++] = 'N'; 10792db270a8SFrederic Weisbecker 1080c09c47caSNamhyung Kim if (tc & BLK_TC_FUA) 1081c09c47caSNamhyung Kim rwbs[i++] = 'F'; 108265796348SLi Zefan if (tc & BLK_TC_AHEAD) 10832db270a8SFrederic Weisbecker rwbs[i++] = 'A'; 108465796348SLi Zefan if (tc & BLK_TC_SYNC) 10852db270a8SFrederic Weisbecker rwbs[i++] = 'S'; 108665796348SLi Zefan if (tc & BLK_TC_META) 10872db270a8SFrederic Weisbecker rwbs[i++] = 'M'; 108818cea459SLi Zefan out: 10892db270a8SFrederic Weisbecker rwbs[i] = '\0'; 10902db270a8SFrederic Weisbecker } 10912db270a8SFrederic Weisbecker 10922db270a8SFrederic Weisbecker static inline 10932db270a8SFrederic Weisbecker const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) 10942db270a8SFrederic Weisbecker { 10952db270a8SFrederic Weisbecker return (const struct blk_io_trace *)ent; 10962db270a8SFrederic Weisbecker } 10972db270a8SFrederic Weisbecker 10982db270a8SFrederic Weisbecker static inline const void *pdu_start(const struct trace_entry *ent) 10992db270a8SFrederic Weisbecker { 11002db270a8SFrederic Weisbecker return te_blk_io_trace(ent) + 1; 11012db270a8SFrederic Weisbecker } 11022db270a8SFrederic Weisbecker 110366de7792SLi Zefan static inline u32 t_action(const struct trace_entry *ent) 110466de7792SLi Zefan { 110566de7792SLi Zefan return te_blk_io_trace(ent)->action; 110666de7792SLi Zefan } 110766de7792SLi Zefan 110866de7792SLi Zefan static inline u32 t_bytes(const struct trace_entry *ent) 110966de7792SLi Zefan { 111066de7792SLi Zefan return te_blk_io_trace(ent)->bytes; 111166de7792SLi Zefan } 111266de7792SLi Zefan 11132db270a8SFrederic Weisbecker static inline u32 t_sec(const struct trace_entry *ent) 11142db270a8SFrederic Weisbecker { 11152db270a8SFrederic Weisbecker return te_blk_io_trace(ent)->bytes >> 9; 11162db270a8SFrederic Weisbecker } 11172db270a8SFrederic Weisbecker 11182db270a8SFrederic Weisbecker static inline unsigned long long t_sector(const struct trace_entry *ent) 11192db270a8SFrederic Weisbecker { 11202db270a8SFrederic Weisbecker return te_blk_io_trace(ent)->sector; 11212db270a8SFrederic Weisbecker } 11222db270a8SFrederic Weisbecker 11232db270a8SFrederic Weisbecker static inline __u16 t_error(const struct trace_entry *ent) 11242db270a8SFrederic Weisbecker { 1125e0dc81beSLi Zefan return te_blk_io_trace(ent)->error; 11262db270a8SFrederic Weisbecker } 11272db270a8SFrederic Weisbecker 11282db270a8SFrederic Weisbecker static __u64 get_pdu_int(const struct trace_entry *ent) 11292db270a8SFrederic Weisbecker { 11302db270a8SFrederic Weisbecker const __u64 *val = pdu_start(ent); 11312db270a8SFrederic Weisbecker return be64_to_cpu(*val); 11322db270a8SFrederic Weisbecker } 11332db270a8SFrederic Weisbecker 11342db270a8SFrederic Weisbecker static void get_pdu_remap(const struct trace_entry *ent, 11352db270a8SFrederic Weisbecker struct blk_io_trace_remap *r) 11362db270a8SFrederic Weisbecker { 11372db270a8SFrederic Weisbecker const struct blk_io_trace_remap *__r = pdu_start(ent); 1138a42aaa3bSAlan D. Brunelle __u64 sector_from = __r->sector_from; 11392db270a8SFrederic Weisbecker 11402db270a8SFrederic Weisbecker r->device_from = be32_to_cpu(__r->device_from); 1141a42aaa3bSAlan D. Brunelle r->device_to = be32_to_cpu(__r->device_to); 1142a42aaa3bSAlan D. Brunelle r->sector_from = be64_to_cpu(sector_from); 11432db270a8SFrederic Weisbecker } 11442db270a8SFrederic Weisbecker 1145b6a4b0c3SLi Zefan typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); 1146b6a4b0c3SLi Zefan 1147b6a4b0c3SLi Zefan static int blk_log_action_classic(struct trace_iterator *iter, const char *act) 11482db270a8SFrederic Weisbecker { 1149c09c47caSNamhyung Kim char rwbs[RWBS_LEN]; 115035ac51bfSLi Zefan unsigned long long ts = iter->ts; 115135ac51bfSLi Zefan unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); 11522db270a8SFrederic Weisbecker unsigned secs = (unsigned long)ts; 1153b6a4b0c3SLi Zefan const struct blk_io_trace *t = te_blk_io_trace(iter->ent); 11542db270a8SFrederic Weisbecker 11552db270a8SFrederic Weisbecker fill_rwbs(rwbs, t); 11562db270a8SFrederic Weisbecker 11572db270a8SFrederic Weisbecker return trace_seq_printf(&iter->seq, 115835ac51bfSLi Zefan "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ", 11592db270a8SFrederic Weisbecker MAJOR(t->device), MINOR(t->device), iter->cpu, 1160b6a4b0c3SLi Zefan secs, nsec_rem, iter->ent->pid, act, rwbs); 11612db270a8SFrederic Weisbecker } 11622db270a8SFrederic Weisbecker 1163b6a4b0c3SLi Zefan static int blk_log_action(struct trace_iterator *iter, const char *act) 11642db270a8SFrederic Weisbecker { 1165c09c47caSNamhyung Kim char rwbs[RWBS_LEN]; 1166b6a4b0c3SLi Zefan const struct blk_io_trace *t = te_blk_io_trace(iter->ent); 1167b6a4b0c3SLi Zefan 11682db270a8SFrederic Weisbecker fill_rwbs(rwbs, t); 1169b6a4b0c3SLi Zefan return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ", 11702db270a8SFrederic Weisbecker MAJOR(t->device), MINOR(t->device), act, rwbs); 11712db270a8SFrederic Weisbecker } 11722db270a8SFrederic Weisbecker 117366de7792SLi Zefan static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent) 117466de7792SLi Zefan { 117504986257SLi Zefan const unsigned char *pdu_buf; 117666de7792SLi Zefan int pdu_len; 117766de7792SLi Zefan int i, end, ret; 117866de7792SLi Zefan 117966de7792SLi Zefan pdu_buf = pdu_start(ent); 118066de7792SLi Zefan pdu_len = te_blk_io_trace(ent)->pdu_len; 118166de7792SLi Zefan 118266de7792SLi Zefan if (!pdu_len) 118366de7792SLi Zefan return 1; 118466de7792SLi Zefan 118566de7792SLi Zefan /* find the last zero that needs to be printed */ 118666de7792SLi Zefan for (end = pdu_len - 1; end >= 0; end--) 118766de7792SLi Zefan if (pdu_buf[end]) 118866de7792SLi Zefan break; 118966de7792SLi Zefan end++; 119066de7792SLi Zefan 119166de7792SLi Zefan if (!trace_seq_putc(s, '(')) 119266de7792SLi Zefan return 0; 119366de7792SLi Zefan 119466de7792SLi Zefan for (i = 0; i < pdu_len; i++) { 119566de7792SLi Zefan 119666de7792SLi Zefan ret = trace_seq_printf(s, "%s%02x", 119766de7792SLi Zefan i == 0 ? "" : " ", pdu_buf[i]); 119866de7792SLi Zefan if (!ret) 119966de7792SLi Zefan return ret; 120066de7792SLi Zefan 120166de7792SLi Zefan /* 120266de7792SLi Zefan * stop when the rest is just zeroes and indicate so 120366de7792SLi Zefan * with a ".." appended 120466de7792SLi Zefan */ 120566de7792SLi Zefan if (i == end && end != pdu_len - 1) 120666de7792SLi Zefan return trace_seq_puts(s, " ..) "); 120766de7792SLi Zefan } 120866de7792SLi Zefan 120966de7792SLi Zefan return trace_seq_puts(s, ") "); 121066de7792SLi Zefan } 121166de7792SLi Zefan 12122db270a8SFrederic Weisbecker static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) 12132db270a8SFrederic Weisbecker { 12144ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 12154ca53085SSteven Rostedt 12164ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 12172db270a8SFrederic Weisbecker 121866de7792SLi Zefan if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { 121966de7792SLi Zefan int ret; 122066de7792SLi Zefan 122166de7792SLi Zefan ret = trace_seq_printf(s, "%u ", t_bytes(ent)); 122266de7792SLi Zefan if (!ret) 122366de7792SLi Zefan return 0; 122466de7792SLi Zefan ret = blk_log_dump_pdu(s, ent); 122566de7792SLi Zefan if (!ret) 122666de7792SLi Zefan return 0; 122766de7792SLi Zefan return trace_seq_printf(s, "[%s]\n", cmd); 122866de7792SLi Zefan } else { 12292db270a8SFrederic Weisbecker if (t_sec(ent)) 12302db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu + %u [%s]\n", 12312db270a8SFrederic Weisbecker t_sector(ent), t_sec(ent), cmd); 12322db270a8SFrederic Weisbecker return trace_seq_printf(s, "[%s]\n", cmd); 12332db270a8SFrederic Weisbecker } 123466de7792SLi Zefan } 12352db270a8SFrederic Weisbecker 12362db270a8SFrederic Weisbecker static int blk_log_with_error(struct trace_seq *s, 12372db270a8SFrederic Weisbecker const struct trace_entry *ent) 12382db270a8SFrederic Weisbecker { 123966de7792SLi Zefan if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { 124066de7792SLi Zefan int ret; 124166de7792SLi Zefan 124266de7792SLi Zefan ret = blk_log_dump_pdu(s, ent); 124366de7792SLi Zefan if (ret) 124466de7792SLi Zefan return trace_seq_printf(s, "[%d]\n", t_error(ent)); 124566de7792SLi Zefan return 0; 124666de7792SLi Zefan } else { 12472db270a8SFrederic Weisbecker if (t_sec(ent)) 124866de7792SLi Zefan return trace_seq_printf(s, "%llu + %u [%d]\n", 124966de7792SLi Zefan t_sector(ent), 12502db270a8SFrederic Weisbecker t_sec(ent), t_error(ent)); 125166de7792SLi Zefan return trace_seq_printf(s, "%llu [%d]\n", 125266de7792SLi Zefan t_sector(ent), t_error(ent)); 125366de7792SLi Zefan } 12542db270a8SFrederic Weisbecker } 12552db270a8SFrederic Weisbecker 12562db270a8SFrederic Weisbecker static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) 12572db270a8SFrederic Weisbecker { 1258a42aaa3bSAlan D. Brunelle struct blk_io_trace_remap r = { .device_from = 0, }; 12592db270a8SFrederic Weisbecker 12602db270a8SFrederic Weisbecker get_pdu_remap(ent, &r); 12612db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", 1262a42aaa3bSAlan D. Brunelle t_sector(ent), t_sec(ent), 1263a42aaa3bSAlan D. Brunelle MAJOR(r.device_from), MINOR(r.device_from), 1264a42aaa3bSAlan D. Brunelle (unsigned long long)r.sector_from); 12652db270a8SFrederic Weisbecker } 12662db270a8SFrederic Weisbecker 12672db270a8SFrederic Weisbecker static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) 12682db270a8SFrederic Weisbecker { 12694ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 12704ca53085SSteven Rostedt 12714ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 12724ca53085SSteven Rostedt 12734ca53085SSteven Rostedt return trace_seq_printf(s, "[%s]\n", cmd); 12742db270a8SFrederic Weisbecker } 12752db270a8SFrederic Weisbecker 12762db270a8SFrederic Weisbecker static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) 12772db270a8SFrederic Weisbecker { 12784ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 12794ca53085SSteven Rostedt 12804ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 12814ca53085SSteven Rostedt 12824ca53085SSteven Rostedt return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); 12832db270a8SFrederic Weisbecker } 12842db270a8SFrederic Weisbecker 12852db270a8SFrederic Weisbecker static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) 12862db270a8SFrederic Weisbecker { 12874ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 12884ca53085SSteven Rostedt 12894ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 12904ca53085SSteven Rostedt 12912db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), 12924ca53085SSteven Rostedt get_pdu_int(ent), cmd); 12932db270a8SFrederic Weisbecker } 12942db270a8SFrederic Weisbecker 129518cea459SLi Zefan static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent) 129618cea459SLi Zefan { 129718cea459SLi Zefan int ret; 129818cea459SLi Zefan const struct blk_io_trace *t = te_blk_io_trace(ent); 129918cea459SLi Zefan 130018cea459SLi Zefan ret = trace_seq_putmem(s, t + 1, t->pdu_len); 130118cea459SLi Zefan if (ret) 130218cea459SLi Zefan return trace_seq_putc(s, '\n'); 130318cea459SLi Zefan return ret; 130418cea459SLi Zefan } 130518cea459SLi Zefan 13062db270a8SFrederic Weisbecker /* 13072db270a8SFrederic Weisbecker * struct tracer operations 13082db270a8SFrederic Weisbecker */ 13092db270a8SFrederic Weisbecker 13102db270a8SFrederic Weisbecker static void blk_tracer_print_header(struct seq_file *m) 13112db270a8SFrederic Weisbecker { 13122db270a8SFrederic Weisbecker if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) 13132db270a8SFrederic Weisbecker return; 13142db270a8SFrederic Weisbecker seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" 13152db270a8SFrederic Weisbecker "# | | | | | |\n"); 13162db270a8SFrederic Weisbecker } 13172db270a8SFrederic Weisbecker 13182db270a8SFrederic Weisbecker static void blk_tracer_start(struct trace_array *tr) 13192db270a8SFrederic Weisbecker { 1320ad5dd549SLi Zefan blk_tracer_enabled = true; 13212db270a8SFrederic Weisbecker } 13222db270a8SFrederic Weisbecker 13232db270a8SFrederic Weisbecker static int blk_tracer_init(struct trace_array *tr) 13242db270a8SFrederic Weisbecker { 13252db270a8SFrederic Weisbecker blk_tr = tr; 13262db270a8SFrederic Weisbecker blk_tracer_start(tr); 13272db270a8SFrederic Weisbecker return 0; 13282db270a8SFrederic Weisbecker } 13292db270a8SFrederic Weisbecker 13302db270a8SFrederic Weisbecker static void blk_tracer_stop(struct trace_array *tr) 13312db270a8SFrederic Weisbecker { 1332ad5dd549SLi Zefan blk_tracer_enabled = false; 13332db270a8SFrederic Weisbecker } 13342db270a8SFrederic Weisbecker 13352db270a8SFrederic Weisbecker static void blk_tracer_reset(struct trace_array *tr) 13362db270a8SFrederic Weisbecker { 13372db270a8SFrederic Weisbecker blk_tracer_stop(tr); 13382db270a8SFrederic Weisbecker } 13392db270a8SFrederic Weisbecker 1340e4955c99SLi Zefan static const struct { 13412db270a8SFrederic Weisbecker const char *act[2]; 13422db270a8SFrederic Weisbecker int (*print)(struct trace_seq *s, const struct trace_entry *ent); 1343e4955c99SLi Zefan } what2act[] = { 13442db270a8SFrederic Weisbecker [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, 13452db270a8SFrederic Weisbecker [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, 13462db270a8SFrederic Weisbecker [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, 13472db270a8SFrederic Weisbecker [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, 13482db270a8SFrederic Weisbecker [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, 13492db270a8SFrederic Weisbecker [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, 13502db270a8SFrederic Weisbecker [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, 13512db270a8SFrederic Weisbecker [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, 13522db270a8SFrederic Weisbecker [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, 13532db270a8SFrederic Weisbecker [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, 135449cac01eSJens Axboe [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, 13552db270a8SFrederic Weisbecker [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, 13562db270a8SFrederic Weisbecker [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, 13572db270a8SFrederic Weisbecker [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, 13582db270a8SFrederic Weisbecker [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, 13592db270a8SFrederic Weisbecker }; 13602db270a8SFrederic Weisbecker 1361b6a4b0c3SLi Zefan static enum print_line_t print_one_line(struct trace_iterator *iter, 1362b6a4b0c3SLi Zefan bool classic) 13632db270a8SFrederic Weisbecker { 13642db270a8SFrederic Weisbecker struct trace_seq *s = &iter->seq; 1365b6a4b0c3SLi Zefan const struct blk_io_trace *t; 1366b6a4b0c3SLi Zefan u16 what; 13672db270a8SFrederic Weisbecker int ret; 1368b6a4b0c3SLi Zefan bool long_act; 1369b6a4b0c3SLi Zefan blk_log_action_t *log_action; 13702db270a8SFrederic Weisbecker 1371b6a4b0c3SLi Zefan t = te_blk_io_trace(iter->ent); 1372b6a4b0c3SLi Zefan what = t->action & ((1 << BLK_TC_SHIFT) - 1); 1373b6a4b0c3SLi Zefan long_act = !!(trace_flags & TRACE_ITER_VERBOSE); 1374b6a4b0c3SLi Zefan log_action = classic ? &blk_log_action_classic : &blk_log_action; 13752db270a8SFrederic Weisbecker 137618cea459SLi Zefan if (t->action == BLK_TN_MESSAGE) { 137718cea459SLi Zefan ret = log_action(iter, long_act ? "message" : "m"); 137818cea459SLi Zefan if (ret) 137918cea459SLi Zefan ret = blk_log_msg(s, iter->ent); 138018cea459SLi Zefan goto out; 138118cea459SLi Zefan } 138218cea459SLi Zefan 1383eb08f8ebSLi Zefan if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) 1384b78825d6SLi Zefan ret = trace_seq_printf(s, "Unknown action %x\n", what); 13852db270a8SFrederic Weisbecker else { 1386b6a4b0c3SLi Zefan ret = log_action(iter, what2act[what].act[long_act]); 13872db270a8SFrederic Weisbecker if (ret) 13882db270a8SFrederic Weisbecker ret = what2act[what].print(s, iter->ent); 13892db270a8SFrederic Weisbecker } 139018cea459SLi Zefan out: 13912db270a8SFrederic Weisbecker return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; 13922db270a8SFrederic Weisbecker } 13932db270a8SFrederic Weisbecker 1394b6a4b0c3SLi Zefan static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, 1395a9a57763SSteven Rostedt int flags, struct trace_event *event) 1396b6a4b0c3SLi Zefan { 1397b6a4b0c3SLi Zefan return print_one_line(iter, false); 1398b6a4b0c3SLi Zefan } 1399b6a4b0c3SLi Zefan 14002db270a8SFrederic Weisbecker static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) 14012db270a8SFrederic Weisbecker { 14022db270a8SFrederic Weisbecker struct trace_seq *s = &iter->seq; 14032db270a8SFrederic Weisbecker struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; 14042db270a8SFrederic Weisbecker const int offset = offsetof(struct blk_io_trace, sector); 14052db270a8SFrederic Weisbecker struct blk_io_trace old = { 14062db270a8SFrederic Weisbecker .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, 14076c051ce0SLi Zefan .time = iter->ts, 14082db270a8SFrederic Weisbecker }; 14092db270a8SFrederic Weisbecker 14102db270a8SFrederic Weisbecker if (!trace_seq_putmem(s, &old, offset)) 14112db270a8SFrederic Weisbecker return 0; 14122db270a8SFrederic Weisbecker return trace_seq_putmem(s, &t->sector, 14132db270a8SFrederic Weisbecker sizeof(old) - offset + t->pdu_len); 14142db270a8SFrederic Weisbecker } 14152db270a8SFrederic Weisbecker 14162db270a8SFrederic Weisbecker static enum print_line_t 1417a9a57763SSteven Rostedt blk_trace_event_print_binary(struct trace_iterator *iter, int flags, 1418a9a57763SSteven Rostedt struct trace_event *event) 14192db270a8SFrederic Weisbecker { 14202db270a8SFrederic Weisbecker return blk_trace_synthesize_old_trace(iter) ? 14212db270a8SFrederic Weisbecker TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; 14222db270a8SFrederic Weisbecker } 14232db270a8SFrederic Weisbecker 14242db270a8SFrederic Weisbecker static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) 14252db270a8SFrederic Weisbecker { 14262db270a8SFrederic Weisbecker if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) 14272db270a8SFrederic Weisbecker return TRACE_TYPE_UNHANDLED; 14282db270a8SFrederic Weisbecker 1429b6a4b0c3SLi Zefan return print_one_line(iter, true); 14302db270a8SFrederic Weisbecker } 14312db270a8SFrederic Weisbecker 1432f3948f88SLi Zefan static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) 1433f3948f88SLi Zefan { 1434f3948f88SLi Zefan /* don't output context-info for blk_classic output */ 1435f3948f88SLi Zefan if (bit == TRACE_BLK_OPT_CLASSIC) { 1436f3948f88SLi Zefan if (set) 1437f3948f88SLi Zefan trace_flags &= ~TRACE_ITER_CONTEXT_INFO; 1438f3948f88SLi Zefan else 1439f3948f88SLi Zefan trace_flags |= TRACE_ITER_CONTEXT_INFO; 1440f3948f88SLi Zefan } 1441f3948f88SLi Zefan return 0; 1442f3948f88SLi Zefan } 1443f3948f88SLi Zefan 14442db270a8SFrederic Weisbecker static struct tracer blk_tracer __read_mostly = { 14452db270a8SFrederic Weisbecker .name = "blk", 14462db270a8SFrederic Weisbecker .init = blk_tracer_init, 14472db270a8SFrederic Weisbecker .reset = blk_tracer_reset, 14482db270a8SFrederic Weisbecker .start = blk_tracer_start, 14492db270a8SFrederic Weisbecker .stop = blk_tracer_stop, 14502db270a8SFrederic Weisbecker .print_header = blk_tracer_print_header, 14512db270a8SFrederic Weisbecker .print_line = blk_tracer_print_line, 14522db270a8SFrederic Weisbecker .flags = &blk_tracer_flags, 1453f3948f88SLi Zefan .set_flag = blk_tracer_set_flag, 14542db270a8SFrederic Weisbecker }; 14552db270a8SFrederic Weisbecker 1456a9a57763SSteven Rostedt static struct trace_event_functions trace_blk_event_funcs = { 14572db270a8SFrederic Weisbecker .trace = blk_trace_event_print, 14582db270a8SFrederic Weisbecker .binary = blk_trace_event_print_binary, 14592db270a8SFrederic Weisbecker }; 14602db270a8SFrederic Weisbecker 1461a9a57763SSteven Rostedt static struct trace_event trace_blk_event = { 1462a9a57763SSteven Rostedt .type = TRACE_BLK, 1463a9a57763SSteven Rostedt .funcs = &trace_blk_event_funcs, 1464a9a57763SSteven Rostedt }; 1465a9a57763SSteven Rostedt 14662db270a8SFrederic Weisbecker static int __init init_blk_tracer(void) 14672db270a8SFrederic Weisbecker { 14682db270a8SFrederic Weisbecker if (!register_ftrace_event(&trace_blk_event)) { 14692db270a8SFrederic Weisbecker pr_warning("Warning: could not register block events\n"); 14702db270a8SFrederic Weisbecker return 1; 14712db270a8SFrederic Weisbecker } 14722db270a8SFrederic Weisbecker 14732db270a8SFrederic Weisbecker if (register_tracer(&blk_tracer) != 0) { 14742db270a8SFrederic Weisbecker pr_warning("Warning: could not register the block tracer\n"); 14752db270a8SFrederic Weisbecker unregister_ftrace_event(&trace_blk_event); 14762db270a8SFrederic Weisbecker return 1; 14772db270a8SFrederic Weisbecker } 14782db270a8SFrederic Weisbecker 14792db270a8SFrederic Weisbecker return 0; 14802db270a8SFrederic Weisbecker } 14812db270a8SFrederic Weisbecker 14822db270a8SFrederic Weisbecker device_initcall(init_blk_tracer); 14832db270a8SFrederic Weisbecker 14842db270a8SFrederic Weisbecker static int blk_trace_remove_queue(struct request_queue *q) 14852db270a8SFrederic Weisbecker { 14862db270a8SFrederic Weisbecker struct blk_trace *bt; 14872db270a8SFrederic Weisbecker 14882db270a8SFrederic Weisbecker bt = xchg(&q->blk_trace, NULL); 14892db270a8SFrederic Weisbecker if (bt == NULL) 14902db270a8SFrederic Weisbecker return -EINVAL; 14912db270a8SFrederic Weisbecker 149217ba97e3SLi Zefan if (atomic_dec_and_test(&blk_probes_ref)) 149317ba97e3SLi Zefan blk_unregister_tracepoints(); 149417ba97e3SLi Zefan 1495ad5dd549SLi Zefan blk_trace_free(bt); 14962db270a8SFrederic Weisbecker return 0; 14972db270a8SFrederic Weisbecker } 14982db270a8SFrederic Weisbecker 14992db270a8SFrederic Weisbecker /* 15002db270a8SFrederic Weisbecker * Setup everything required to start tracing 15012db270a8SFrederic Weisbecker */ 15029908c309SLi Zefan static int blk_trace_setup_queue(struct request_queue *q, 15039908c309SLi Zefan struct block_device *bdev) 15042db270a8SFrederic Weisbecker { 15052db270a8SFrederic Weisbecker struct blk_trace *old_bt, *bt = NULL; 150618cea459SLi Zefan int ret = -ENOMEM; 15072db270a8SFrederic Weisbecker 15082db270a8SFrederic Weisbecker bt = kzalloc(sizeof(*bt), GFP_KERNEL); 15092db270a8SFrederic Weisbecker if (!bt) 151015152e44SLi Zefan return -ENOMEM; 15112db270a8SFrederic Weisbecker 151218cea459SLi Zefan bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); 151318cea459SLi Zefan if (!bt->msg_data) 151418cea459SLi Zefan goto free_bt; 151518cea459SLi Zefan 15169908c309SLi Zefan bt->dev = bdev->bd_dev; 15172db270a8SFrederic Weisbecker bt->act_mask = (u16)-1; 15189908c309SLi Zefan 15199908c309SLi Zefan blk_trace_setup_lba(bt, bdev); 15202db270a8SFrederic Weisbecker 15212db270a8SFrederic Weisbecker old_bt = xchg(&q->blk_trace, bt); 15222db270a8SFrederic Weisbecker if (old_bt != NULL) { 15232db270a8SFrederic Weisbecker (void)xchg(&q->blk_trace, old_bt); 152418cea459SLi Zefan ret = -EBUSY; 152518cea459SLi Zefan goto free_bt; 15262db270a8SFrederic Weisbecker } 152715152e44SLi Zefan 152817ba97e3SLi Zefan if (atomic_inc_return(&blk_probes_ref) == 1) 152917ba97e3SLi Zefan blk_register_tracepoints(); 15302db270a8SFrederic Weisbecker return 0; 153118cea459SLi Zefan 153218cea459SLi Zefan free_bt: 153318cea459SLi Zefan blk_trace_free(bt); 153418cea459SLi Zefan return ret; 15352db270a8SFrederic Weisbecker } 15362db270a8SFrederic Weisbecker 15372db270a8SFrederic Weisbecker /* 15382db270a8SFrederic Weisbecker * sysfs interface to enable and configure tracing 15392db270a8SFrederic Weisbecker */ 15402db270a8SFrederic Weisbecker 15412db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_show(struct device *dev, 15422db270a8SFrederic Weisbecker struct device_attribute *attr, 15432db270a8SFrederic Weisbecker char *buf); 15442db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_store(struct device *dev, 15452db270a8SFrederic Weisbecker struct device_attribute *attr, 15462db270a8SFrederic Weisbecker const char *buf, size_t count); 15472db270a8SFrederic Weisbecker #define BLK_TRACE_DEVICE_ATTR(_name) \ 15482db270a8SFrederic Weisbecker DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ 15492db270a8SFrederic Weisbecker sysfs_blk_trace_attr_show, \ 15502db270a8SFrederic Weisbecker sysfs_blk_trace_attr_store) 15512db270a8SFrederic Weisbecker 1552cd649b8bSLi Zefan static BLK_TRACE_DEVICE_ATTR(enable); 15532db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(act_mask); 15542db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(pid); 15552db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(start_lba); 15562db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(end_lba); 15572db270a8SFrederic Weisbecker 15582db270a8SFrederic Weisbecker static struct attribute *blk_trace_attrs[] = { 15592db270a8SFrederic Weisbecker &dev_attr_enable.attr, 15602db270a8SFrederic Weisbecker &dev_attr_act_mask.attr, 15612db270a8SFrederic Weisbecker &dev_attr_pid.attr, 15622db270a8SFrederic Weisbecker &dev_attr_start_lba.attr, 15632db270a8SFrederic Weisbecker &dev_attr_end_lba.attr, 15642db270a8SFrederic Weisbecker NULL 15652db270a8SFrederic Weisbecker }; 15662db270a8SFrederic Weisbecker 15672db270a8SFrederic Weisbecker struct attribute_group blk_trace_attr_group = { 15682db270a8SFrederic Weisbecker .name = "trace", 15692db270a8SFrederic Weisbecker .attrs = blk_trace_attrs, 15702db270a8SFrederic Weisbecker }; 15712db270a8SFrederic Weisbecker 157209341997SLi Zefan static const struct { 157309341997SLi Zefan int mask; 157409341997SLi Zefan const char *str; 157509341997SLi Zefan } mask_maps[] = { 157609341997SLi Zefan { BLK_TC_READ, "read" }, 157709341997SLi Zefan { BLK_TC_WRITE, "write" }, 1578c09c47caSNamhyung Kim { BLK_TC_FLUSH, "flush" }, 157909341997SLi Zefan { BLK_TC_SYNC, "sync" }, 158009341997SLi Zefan { BLK_TC_QUEUE, "queue" }, 158109341997SLi Zefan { BLK_TC_REQUEUE, "requeue" }, 158209341997SLi Zefan { BLK_TC_ISSUE, "issue" }, 158309341997SLi Zefan { BLK_TC_COMPLETE, "complete" }, 158409341997SLi Zefan { BLK_TC_FS, "fs" }, 158509341997SLi Zefan { BLK_TC_PC, "pc" }, 158609341997SLi Zefan { BLK_TC_AHEAD, "ahead" }, 158709341997SLi Zefan { BLK_TC_META, "meta" }, 158809341997SLi Zefan { BLK_TC_DISCARD, "discard" }, 158909341997SLi Zefan { BLK_TC_DRV_DATA, "drv_data" }, 1590c09c47caSNamhyung Kim { BLK_TC_FUA, "fua" }, 159109341997SLi Zefan }; 159209341997SLi Zefan 159309341997SLi Zefan static int blk_trace_str2mask(const char *str) 15942db270a8SFrederic Weisbecker { 159509341997SLi Zefan int i; 15962db270a8SFrederic Weisbecker int mask = 0; 15979eb85125SLi Zefan char *buf, *s, *token; 15982db270a8SFrederic Weisbecker 15999eb85125SLi Zefan buf = kstrdup(str, GFP_KERNEL); 16009eb85125SLi Zefan if (buf == NULL) 16012db270a8SFrederic Weisbecker return -ENOMEM; 16029eb85125SLi Zefan s = strstrip(buf); 16032db270a8SFrederic Weisbecker 16042db270a8SFrederic Weisbecker while (1) { 160509341997SLi Zefan token = strsep(&s, ","); 160609341997SLi Zefan if (token == NULL) 16072db270a8SFrederic Weisbecker break; 16082db270a8SFrederic Weisbecker 160909341997SLi Zefan if (*token == '\0') 161009341997SLi Zefan continue; 161109341997SLi Zefan 161209341997SLi Zefan for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { 161309341997SLi Zefan if (strcasecmp(token, mask_maps[i].str) == 0) { 161409341997SLi Zefan mask |= mask_maps[i].mask; 161509341997SLi Zefan break; 16162db270a8SFrederic Weisbecker } 161709341997SLi Zefan } 161809341997SLi Zefan if (i == ARRAY_SIZE(mask_maps)) { 161909341997SLi Zefan mask = -EINVAL; 162009341997SLi Zefan break; 162109341997SLi Zefan } 162209341997SLi Zefan } 16239eb85125SLi Zefan kfree(buf); 16242db270a8SFrederic Weisbecker 16252db270a8SFrederic Weisbecker return mask; 16262db270a8SFrederic Weisbecker } 16272db270a8SFrederic Weisbecker 162809341997SLi Zefan static ssize_t blk_trace_mask2str(char *buf, int mask) 162909341997SLi Zefan { 163009341997SLi Zefan int i; 163109341997SLi Zefan char *p = buf; 163209341997SLi Zefan 163309341997SLi Zefan for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { 163409341997SLi Zefan if (mask & mask_maps[i].mask) { 163509341997SLi Zefan p += sprintf(p, "%s%s", 163609341997SLi Zefan (p == buf) ? "" : ",", mask_maps[i].str); 163709341997SLi Zefan } 163809341997SLi Zefan } 163909341997SLi Zefan *p++ = '\n'; 164009341997SLi Zefan 164109341997SLi Zefan return p - buf; 164209341997SLi Zefan } 164309341997SLi Zefan 1644b125130bSLi Zefan static struct request_queue *blk_trace_get_queue(struct block_device *bdev) 1645b125130bSLi Zefan { 1646b125130bSLi Zefan if (bdev->bd_disk == NULL) 1647b125130bSLi Zefan return NULL; 1648b125130bSLi Zefan 1649b125130bSLi Zefan return bdev_get_queue(bdev); 1650b125130bSLi Zefan } 1651b125130bSLi Zefan 16522db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_show(struct device *dev, 16532db270a8SFrederic Weisbecker struct device_attribute *attr, 16542db270a8SFrederic Weisbecker char *buf) 16552db270a8SFrederic Weisbecker { 16562db270a8SFrederic Weisbecker struct hd_struct *p = dev_to_part(dev); 16572db270a8SFrederic Weisbecker struct request_queue *q; 16582db270a8SFrederic Weisbecker struct block_device *bdev; 16592db270a8SFrederic Weisbecker ssize_t ret = -ENXIO; 16602db270a8SFrederic Weisbecker 16612db270a8SFrederic Weisbecker bdev = bdget(part_devt(p)); 16622db270a8SFrederic Weisbecker if (bdev == NULL) 166301b284f9SArnd Bergmann goto out; 16642db270a8SFrederic Weisbecker 1665b125130bSLi Zefan q = blk_trace_get_queue(bdev); 16662db270a8SFrederic Weisbecker if (q == NULL) 16672db270a8SFrederic Weisbecker goto out_bdput; 1668b125130bSLi Zefan 16692db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 1670cd649b8bSLi Zefan 1671cd649b8bSLi Zefan if (attr == &dev_attr_enable) { 1672cd649b8bSLi Zefan ret = sprintf(buf, "%u\n", !!q->blk_trace); 1673cd649b8bSLi Zefan goto out_unlock_bdev; 1674cd649b8bSLi Zefan } 1675cd649b8bSLi Zefan 16762db270a8SFrederic Weisbecker if (q->blk_trace == NULL) 16772db270a8SFrederic Weisbecker ret = sprintf(buf, "disabled\n"); 16782db270a8SFrederic Weisbecker else if (attr == &dev_attr_act_mask) 167909341997SLi Zefan ret = blk_trace_mask2str(buf, q->blk_trace->act_mask); 16802db270a8SFrederic Weisbecker else if (attr == &dev_attr_pid) 16812db270a8SFrederic Weisbecker ret = sprintf(buf, "%u\n", q->blk_trace->pid); 16822db270a8SFrederic Weisbecker else if (attr == &dev_attr_start_lba) 16832db270a8SFrederic Weisbecker ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); 16842db270a8SFrederic Weisbecker else if (attr == &dev_attr_end_lba) 16852db270a8SFrederic Weisbecker ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); 1686cd649b8bSLi Zefan 1687cd649b8bSLi Zefan out_unlock_bdev: 16882db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 16892db270a8SFrederic Weisbecker out_bdput: 16902db270a8SFrederic Weisbecker bdput(bdev); 169101b284f9SArnd Bergmann out: 16922db270a8SFrederic Weisbecker return ret; 16932db270a8SFrederic Weisbecker } 16942db270a8SFrederic Weisbecker 16952db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_store(struct device *dev, 16962db270a8SFrederic Weisbecker struct device_attribute *attr, 16972db270a8SFrederic Weisbecker const char *buf, size_t count) 16982db270a8SFrederic Weisbecker { 16992db270a8SFrederic Weisbecker struct block_device *bdev; 17002db270a8SFrederic Weisbecker struct request_queue *q; 17012db270a8SFrederic Weisbecker struct hd_struct *p; 17022db270a8SFrederic Weisbecker u64 value; 170309341997SLi Zefan ssize_t ret = -EINVAL; 17042db270a8SFrederic Weisbecker 17052db270a8SFrederic Weisbecker if (count == 0) 17062db270a8SFrederic Weisbecker goto out; 17072db270a8SFrederic Weisbecker 17082db270a8SFrederic Weisbecker if (attr == &dev_attr_act_mask) { 17092db270a8SFrederic Weisbecker if (sscanf(buf, "%llx", &value) != 1) { 17102db270a8SFrederic Weisbecker /* Assume it is a list of trace category names */ 171109341997SLi Zefan ret = blk_trace_str2mask(buf); 171209341997SLi Zefan if (ret < 0) 17132db270a8SFrederic Weisbecker goto out; 171409341997SLi Zefan value = ret; 17152db270a8SFrederic Weisbecker } 17162db270a8SFrederic Weisbecker } else if (sscanf(buf, "%llu", &value) != 1) 17172db270a8SFrederic Weisbecker goto out; 17182db270a8SFrederic Weisbecker 171909341997SLi Zefan ret = -ENXIO; 172009341997SLi Zefan 17212db270a8SFrederic Weisbecker p = dev_to_part(dev); 17222db270a8SFrederic Weisbecker bdev = bdget(part_devt(p)); 17232db270a8SFrederic Weisbecker if (bdev == NULL) 172401b284f9SArnd Bergmann goto out; 17252db270a8SFrederic Weisbecker 1726b125130bSLi Zefan q = blk_trace_get_queue(bdev); 17272db270a8SFrederic Weisbecker if (q == NULL) 17282db270a8SFrederic Weisbecker goto out_bdput; 17292db270a8SFrederic Weisbecker 17302db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 1731cd649b8bSLi Zefan 1732cd649b8bSLi Zefan if (attr == &dev_attr_enable) { 1733cd649b8bSLi Zefan if (value) 17349908c309SLi Zefan ret = blk_trace_setup_queue(q, bdev); 1735cd649b8bSLi Zefan else 1736cd649b8bSLi Zefan ret = blk_trace_remove_queue(q); 1737cd649b8bSLi Zefan goto out_unlock_bdev; 1738cd649b8bSLi Zefan } 1739cd649b8bSLi Zefan 17402db270a8SFrederic Weisbecker ret = 0; 17412db270a8SFrederic Weisbecker if (q->blk_trace == NULL) 17429908c309SLi Zefan ret = blk_trace_setup_queue(q, bdev); 17432db270a8SFrederic Weisbecker 17442db270a8SFrederic Weisbecker if (ret == 0) { 17452db270a8SFrederic Weisbecker if (attr == &dev_attr_act_mask) 17462db270a8SFrederic Weisbecker q->blk_trace->act_mask = value; 17472db270a8SFrederic Weisbecker else if (attr == &dev_attr_pid) 17482db270a8SFrederic Weisbecker q->blk_trace->pid = value; 17492db270a8SFrederic Weisbecker else if (attr == &dev_attr_start_lba) 17502db270a8SFrederic Weisbecker q->blk_trace->start_lba = value; 17512db270a8SFrederic Weisbecker else if (attr == &dev_attr_end_lba) 17522db270a8SFrederic Weisbecker q->blk_trace->end_lba = value; 17532db270a8SFrederic Weisbecker } 1754cd649b8bSLi Zefan 1755cd649b8bSLi Zefan out_unlock_bdev: 17562db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 17572db270a8SFrederic Weisbecker out_bdput: 17582db270a8SFrederic Weisbecker bdput(bdev); 17592db270a8SFrederic Weisbecker out: 1760cd649b8bSLi Zefan return ret ? ret : count; 17612db270a8SFrederic Weisbecker } 1762cd649b8bSLi Zefan 17631d54ad6dSLi Zefan int blk_trace_init_sysfs(struct device *dev) 17641d54ad6dSLi Zefan { 17651d54ad6dSLi Zefan return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); 17661d54ad6dSLi Zefan } 17671d54ad6dSLi Zefan 176848c0d4d4SZdenek Kabelac void blk_trace_remove_sysfs(struct device *dev) 176948c0d4d4SZdenek Kabelac { 177048c0d4d4SZdenek Kabelac sysfs_remove_group(&dev->kobj, &blk_trace_attr_group); 177148c0d4d4SZdenek Kabelac } 177248c0d4d4SZdenek Kabelac 177355782138SLi Zefan #endif /* CONFIG_BLK_DEV_IO_TRACE */ 177455782138SLi Zefan 177555782138SLi Zefan #ifdef CONFIG_EVENT_TRACING 177655782138SLi Zefan 177755782138SLi Zefan void blk_dump_cmd(char *buf, struct request *rq) 177855782138SLi Zefan { 177955782138SLi Zefan int i, end; 178055782138SLi Zefan int len = rq->cmd_len; 178155782138SLi Zefan unsigned char *cmd = rq->cmd; 178255782138SLi Zefan 178333659ebbSChristoph Hellwig if (rq->cmd_type != REQ_TYPE_BLOCK_PC) { 178455782138SLi Zefan buf[0] = '\0'; 178555782138SLi Zefan return; 178655782138SLi Zefan } 178755782138SLi Zefan 178855782138SLi Zefan for (end = len - 1; end >= 0; end--) 178955782138SLi Zefan if (cmd[end]) 179055782138SLi Zefan break; 179155782138SLi Zefan end++; 179255782138SLi Zefan 179355782138SLi Zefan for (i = 0; i < len; i++) { 179455782138SLi Zefan buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]); 179555782138SLi Zefan if (i == end && end != len - 1) { 179655782138SLi Zefan sprintf(buf, " .."); 179755782138SLi Zefan break; 179855782138SLi Zefan } 179955782138SLi Zefan } 180055782138SLi Zefan } 180155782138SLi Zefan 180255782138SLi Zefan void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) 180355782138SLi Zefan { 180455782138SLi Zefan int i = 0; 180555782138SLi Zefan 1806c09c47caSNamhyung Kim if (rw & REQ_FLUSH) 1807c09c47caSNamhyung Kim rwbs[i++] = 'F'; 1808c09c47caSNamhyung Kim 180955782138SLi Zefan if (rw & WRITE) 181055782138SLi Zefan rwbs[i++] = 'W'; 18117b6d91daSChristoph Hellwig else if (rw & REQ_DISCARD) 181255782138SLi Zefan rwbs[i++] = 'D'; 181355782138SLi Zefan else if (bytes) 181455782138SLi Zefan rwbs[i++] = 'R'; 181555782138SLi Zefan else 181655782138SLi Zefan rwbs[i++] = 'N'; 181755782138SLi Zefan 1818c09c47caSNamhyung Kim if (rw & REQ_FUA) 1819c09c47caSNamhyung Kim rwbs[i++] = 'F'; 18207b6d91daSChristoph Hellwig if (rw & REQ_RAHEAD) 182155782138SLi Zefan rwbs[i++] = 'A'; 18227b6d91daSChristoph Hellwig if (rw & REQ_SYNC) 182355782138SLi Zefan rwbs[i++] = 'S'; 18247b6d91daSChristoph Hellwig if (rw & REQ_META) 182555782138SLi Zefan rwbs[i++] = 'M'; 18268d57a98cSAdrian Hunter if (rw & REQ_SECURE) 18278d57a98cSAdrian Hunter rwbs[i++] = 'E'; 182855782138SLi Zefan 182955782138SLi Zefan rwbs[i] = '\0'; 183055782138SLi Zefan } 18319ca8f8e5SKent Overstreet EXPORT_SYMBOL_GPL(blk_fill_rwbs); 183255782138SLi Zefan 183355782138SLi Zefan #endif /* CONFIG_EVENT_TRACING */ 183455782138SLi Zefan 1835