12db270a8SFrederic Weisbecker /* 22db270a8SFrederic Weisbecker * Copyright (C) 2006 Jens Axboe <axboe@kernel.dk> 32db270a8SFrederic Weisbecker * 42db270a8SFrederic Weisbecker * This program is free software; you can redistribute it and/or modify 52db270a8SFrederic Weisbecker * it under the terms of the GNU General Public License version 2 as 62db270a8SFrederic Weisbecker * published by the Free Software Foundation. 72db270a8SFrederic Weisbecker * 82db270a8SFrederic Weisbecker * This program is distributed in the hope that it will be useful, 92db270a8SFrederic Weisbecker * but WITHOUT ANY WARRANTY; without even the implied warranty of 102db270a8SFrederic Weisbecker * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 112db270a8SFrederic Weisbecker * GNU General Public License for more details. 122db270a8SFrederic Weisbecker * 132db270a8SFrederic Weisbecker * You should have received a copy of the GNU General Public License 142db270a8SFrederic Weisbecker * along with this program; if not, write to the Free Software 152db270a8SFrederic Weisbecker * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 162db270a8SFrederic Weisbecker * 172db270a8SFrederic Weisbecker */ 182db270a8SFrederic Weisbecker #include <linux/kernel.h> 192db270a8SFrederic Weisbecker #include <linux/blkdev.h> 202db270a8SFrederic Weisbecker #include <linux/blktrace_api.h> 212db270a8SFrederic Weisbecker #include <linux/percpu.h> 222db270a8SFrederic Weisbecker #include <linux/init.h> 232db270a8SFrederic Weisbecker #include <linux/mutex.h> 242db270a8SFrederic Weisbecker #include <linux/debugfs.h> 252db270a8SFrederic Weisbecker #include <linux/time.h> 262db270a8SFrederic Weisbecker #include <trace/block.h> 272db270a8SFrederic Weisbecker #include <linux/uaccess.h> 282db270a8SFrederic Weisbecker #include "trace_output.h" 292db270a8SFrederic Weisbecker 302db270a8SFrederic Weisbecker static unsigned int blktrace_seq __read_mostly = 1; 312db270a8SFrederic Weisbecker 322db270a8SFrederic Weisbecker static struct trace_array *blk_tr; 335006ea73SLi Zefan static bool blk_tracer_enabled __read_mostly; 342db270a8SFrederic Weisbecker 352db270a8SFrederic Weisbecker /* Select an alternative, minimalistic output than the original one */ 362db270a8SFrederic Weisbecker #define TRACE_BLK_OPT_CLASSIC 0x1 372db270a8SFrederic Weisbecker 382db270a8SFrederic Weisbecker static struct tracer_opt blk_tracer_opts[] = { 392db270a8SFrederic Weisbecker /* Default disable the minimalistic output */ 402db270a8SFrederic Weisbecker { TRACER_OPT(blk_classic, TRACE_BLK_OPT_CLASSIC) }, 412db270a8SFrederic Weisbecker { } 422db270a8SFrederic Weisbecker }; 432db270a8SFrederic Weisbecker 442db270a8SFrederic Weisbecker static struct tracer_flags blk_tracer_flags = { 452db270a8SFrederic Weisbecker .val = 0, 462db270a8SFrederic Weisbecker .opts = blk_tracer_opts, 472db270a8SFrederic Weisbecker }; 482db270a8SFrederic Weisbecker 492db270a8SFrederic Weisbecker /* Global reference count of probes */ 502db270a8SFrederic Weisbecker static atomic_t blk_probes_ref = ATOMIC_INIT(0); 512db270a8SFrederic Weisbecker 523c289ba7SLi Zefan static void blk_register_tracepoints(void); 532db270a8SFrederic Weisbecker static void blk_unregister_tracepoints(void); 542db270a8SFrederic Weisbecker 552db270a8SFrederic Weisbecker /* 562db270a8SFrederic Weisbecker * Send out a notify message. 572db270a8SFrederic Weisbecker */ 582db270a8SFrederic Weisbecker static void trace_note(struct blk_trace *bt, pid_t pid, int action, 592db270a8SFrederic Weisbecker const void *data, size_t len) 602db270a8SFrederic Weisbecker { 612db270a8SFrederic Weisbecker struct blk_io_trace *t; 6218cea459SLi Zefan struct ring_buffer_event *event = NULL; 6318cea459SLi Zefan int pc = 0; 6418cea459SLi Zefan int cpu = smp_processor_id(); 6518cea459SLi Zefan bool blk_tracer = blk_tracer_enabled; 6618cea459SLi Zefan 6718cea459SLi Zefan if (blk_tracer) { 6818cea459SLi Zefan pc = preempt_count(); 6918cea459SLi Zefan event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK, 7018cea459SLi Zefan sizeof(*t) + len, 7118cea459SLi Zefan 0, pc); 7218cea459SLi Zefan if (!event) 7318cea459SLi Zefan return; 7418cea459SLi Zefan t = ring_buffer_event_data(event); 7518cea459SLi Zefan goto record_it; 7618cea459SLi Zefan } 772db270a8SFrederic Weisbecker 782db270a8SFrederic Weisbecker if (!bt->rchan) 792db270a8SFrederic Weisbecker return; 802db270a8SFrederic Weisbecker 812db270a8SFrederic Weisbecker t = relay_reserve(bt->rchan, sizeof(*t) + len); 822db270a8SFrederic Weisbecker if (t) { 832db270a8SFrederic Weisbecker t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; 842db270a8SFrederic Weisbecker t->time = ktime_to_ns(ktime_get()); 8518cea459SLi Zefan record_it: 862db270a8SFrederic Weisbecker t->device = bt->dev; 872db270a8SFrederic Weisbecker t->action = action; 882db270a8SFrederic Weisbecker t->pid = pid; 892db270a8SFrederic Weisbecker t->cpu = cpu; 902db270a8SFrederic Weisbecker t->pdu_len = len; 912db270a8SFrederic Weisbecker memcpy((void *) t + sizeof(*t), data, len); 9218cea459SLi Zefan 9318cea459SLi Zefan if (blk_tracer) 9418cea459SLi Zefan trace_buffer_unlock_commit(blk_tr, event, 0, pc); 952db270a8SFrederic Weisbecker } 962db270a8SFrederic Weisbecker } 972db270a8SFrederic Weisbecker 982db270a8SFrederic Weisbecker /* 992db270a8SFrederic Weisbecker * Send out a notify for this process, if we haven't done so since a trace 1002db270a8SFrederic Weisbecker * started 1012db270a8SFrederic Weisbecker */ 1022db270a8SFrederic Weisbecker static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) 1032db270a8SFrederic Weisbecker { 1042db270a8SFrederic Weisbecker tsk->btrace_seq = blktrace_seq; 1052db270a8SFrederic Weisbecker trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm)); 1062db270a8SFrederic Weisbecker } 1072db270a8SFrederic Weisbecker 1082db270a8SFrederic Weisbecker static void trace_note_time(struct blk_trace *bt) 1092db270a8SFrederic Weisbecker { 1102db270a8SFrederic Weisbecker struct timespec now; 1112db270a8SFrederic Weisbecker unsigned long flags; 1122db270a8SFrederic Weisbecker u32 words[2]; 1132db270a8SFrederic Weisbecker 1142db270a8SFrederic Weisbecker getnstimeofday(&now); 1152db270a8SFrederic Weisbecker words[0] = now.tv_sec; 1162db270a8SFrederic Weisbecker words[1] = now.tv_nsec; 1172db270a8SFrederic Weisbecker 1182db270a8SFrederic Weisbecker local_irq_save(flags); 1192db270a8SFrederic Weisbecker trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words)); 1202db270a8SFrederic Weisbecker local_irq_restore(flags); 1212db270a8SFrederic Weisbecker } 1222db270a8SFrederic Weisbecker 1232db270a8SFrederic Weisbecker void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) 1242db270a8SFrederic Weisbecker { 1252db270a8SFrederic Weisbecker int n; 1262db270a8SFrederic Weisbecker va_list args; 1272db270a8SFrederic Weisbecker unsigned long flags; 1282db270a8SFrederic Weisbecker char *buf; 1292db270a8SFrederic Weisbecker 13018cea459SLi Zefan if (unlikely(bt->trace_state != Blktrace_running && 13118cea459SLi Zefan !blk_tracer_enabled)) 1322db270a8SFrederic Weisbecker return; 1332db270a8SFrederic Weisbecker 1342db270a8SFrederic Weisbecker local_irq_save(flags); 1352db270a8SFrederic Weisbecker buf = per_cpu_ptr(bt->msg_data, smp_processor_id()); 1362db270a8SFrederic Weisbecker va_start(args, fmt); 1372db270a8SFrederic Weisbecker n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); 1382db270a8SFrederic Weisbecker va_end(args); 1392db270a8SFrederic Weisbecker 1402db270a8SFrederic Weisbecker trace_note(bt, 0, BLK_TN_MESSAGE, buf, n); 1412db270a8SFrederic Weisbecker local_irq_restore(flags); 1422db270a8SFrederic Weisbecker } 1432db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(__trace_note_message); 1442db270a8SFrederic Weisbecker 1452db270a8SFrederic Weisbecker static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, 1462db270a8SFrederic Weisbecker pid_t pid) 1472db270a8SFrederic Weisbecker { 1482db270a8SFrederic Weisbecker if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) 1492db270a8SFrederic Weisbecker return 1; 150d0deef5bSShawn Du if (sector && (sector < bt->start_lba || sector > bt->end_lba)) 1512db270a8SFrederic Weisbecker return 1; 1522db270a8SFrederic Weisbecker if (bt->pid && pid != bt->pid) 1532db270a8SFrederic Weisbecker return 1; 1542db270a8SFrederic Weisbecker 1552db270a8SFrederic Weisbecker return 0; 1562db270a8SFrederic Weisbecker } 1572db270a8SFrederic Weisbecker 1582db270a8SFrederic Weisbecker /* 1592db270a8SFrederic Weisbecker * Data direction bit lookup 1602db270a8SFrederic Weisbecker */ 161e4955c99SLi Zefan static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ), 1622db270a8SFrederic Weisbecker BLK_TC_ACT(BLK_TC_WRITE) }; 1632db270a8SFrederic Weisbecker 1642db270a8SFrederic Weisbecker /* The ilog2() calls fall out because they're constant */ 1652db270a8SFrederic Weisbecker #define MASK_TC_BIT(rw, __name) ((rw & (1 << BIO_RW_ ## __name)) << \ 1662db270a8SFrederic Weisbecker (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - BIO_RW_ ## __name)) 1672db270a8SFrederic Weisbecker 1682db270a8SFrederic Weisbecker /* 1692db270a8SFrederic Weisbecker * The worker for the various blk_add_trace*() types. Fills out a 1702db270a8SFrederic Weisbecker * blk_io_trace structure and places it in a per-cpu subbuffer. 1712db270a8SFrederic Weisbecker */ 1722db270a8SFrederic Weisbecker static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, 1732db270a8SFrederic Weisbecker int rw, u32 what, int error, int pdu_len, void *pdu_data) 1742db270a8SFrederic Weisbecker { 1752db270a8SFrederic Weisbecker struct task_struct *tsk = current; 1762db270a8SFrederic Weisbecker struct ring_buffer_event *event = NULL; 1772db270a8SFrederic Weisbecker struct blk_io_trace *t; 1782db270a8SFrederic Weisbecker unsigned long flags = 0; 1792db270a8SFrederic Weisbecker unsigned long *sequence; 1802db270a8SFrederic Weisbecker pid_t pid; 1812db270a8SFrederic Weisbecker int cpu, pc = 0; 18218cea459SLi Zefan bool blk_tracer = blk_tracer_enabled; 1832db270a8SFrederic Weisbecker 18418cea459SLi Zefan if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer)) 1852db270a8SFrederic Weisbecker return; 1862db270a8SFrederic Weisbecker 1872db270a8SFrederic Weisbecker what |= ddir_act[rw & WRITE]; 1882db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, BARRIER); 18972c26c9aSIngo Molnar what |= MASK_TC_BIT(rw, SYNCIO); 1902db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, AHEAD); 1912db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, META); 1922db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, DISCARD); 1932db270a8SFrederic Weisbecker 1942db270a8SFrederic Weisbecker pid = tsk->pid; 195d0deef5bSShawn Du if (act_log_check(bt, what, sector, pid)) 1962db270a8SFrederic Weisbecker return; 1972db270a8SFrederic Weisbecker cpu = raw_smp_processor_id(); 1982db270a8SFrederic Weisbecker 19918cea459SLi Zefan if (blk_tracer) { 2002db270a8SFrederic Weisbecker tracing_record_cmdline(current); 2012db270a8SFrederic Weisbecker 2022db270a8SFrederic Weisbecker pc = preempt_count(); 2032db270a8SFrederic Weisbecker event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK, 2042db270a8SFrederic Weisbecker sizeof(*t) + pdu_len, 2052db270a8SFrederic Weisbecker 0, pc); 2062db270a8SFrederic Weisbecker if (!event) 2072db270a8SFrederic Weisbecker return; 2082db270a8SFrederic Weisbecker t = ring_buffer_event_data(event); 2092db270a8SFrederic Weisbecker goto record_it; 2102db270a8SFrederic Weisbecker } 2112db270a8SFrederic Weisbecker 2122db270a8SFrederic Weisbecker /* 2132db270a8SFrederic Weisbecker * A word about the locking here - we disable interrupts to reserve 2142db270a8SFrederic Weisbecker * some space in the relay per-cpu buffer, to prevent an irq 2152db270a8SFrederic Weisbecker * from coming in and stepping on our toes. 2162db270a8SFrederic Weisbecker */ 2172db270a8SFrederic Weisbecker local_irq_save(flags); 2182db270a8SFrederic Weisbecker 2192db270a8SFrederic Weisbecker if (unlikely(tsk->btrace_seq != blktrace_seq)) 2202db270a8SFrederic Weisbecker trace_note_tsk(bt, tsk); 2212db270a8SFrederic Weisbecker 2222db270a8SFrederic Weisbecker t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); 2232db270a8SFrederic Weisbecker if (t) { 2242db270a8SFrederic Weisbecker sequence = per_cpu_ptr(bt->sequence, cpu); 2252db270a8SFrederic Weisbecker 2262db270a8SFrederic Weisbecker t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; 2272db270a8SFrederic Weisbecker t->sequence = ++(*sequence); 2282db270a8SFrederic Weisbecker t->time = ktime_to_ns(ktime_get()); 2292db270a8SFrederic Weisbecker record_it: 2302db270a8SFrederic Weisbecker /* 2312db270a8SFrederic Weisbecker * These two are not needed in ftrace as they are in the 2322db270a8SFrederic Weisbecker * generic trace_entry, filled by tracing_generic_entry_update, 2332db270a8SFrederic Weisbecker * but for the trace_event->bin() synthesizer benefit we do it 2342db270a8SFrederic Weisbecker * here too. 2352db270a8SFrederic Weisbecker */ 2362db270a8SFrederic Weisbecker t->cpu = cpu; 2372db270a8SFrederic Weisbecker t->pid = pid; 2382db270a8SFrederic Weisbecker 2392db270a8SFrederic Weisbecker t->sector = sector; 2402db270a8SFrederic Weisbecker t->bytes = bytes; 2412db270a8SFrederic Weisbecker t->action = what; 2422db270a8SFrederic Weisbecker t->device = bt->dev; 2432db270a8SFrederic Weisbecker t->error = error; 2442db270a8SFrederic Weisbecker t->pdu_len = pdu_len; 2452db270a8SFrederic Weisbecker 2462db270a8SFrederic Weisbecker if (pdu_len) 2472db270a8SFrederic Weisbecker memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); 2482db270a8SFrederic Weisbecker 24918cea459SLi Zefan if (blk_tracer) { 2502db270a8SFrederic Weisbecker trace_buffer_unlock_commit(blk_tr, event, 0, pc); 2512db270a8SFrederic Weisbecker return; 2522db270a8SFrederic Weisbecker } 2532db270a8SFrederic Weisbecker } 2542db270a8SFrederic Weisbecker 2552db270a8SFrederic Weisbecker local_irq_restore(flags); 2562db270a8SFrederic Weisbecker } 2572db270a8SFrederic Weisbecker 2582db270a8SFrederic Weisbecker static struct dentry *blk_tree_root; 2592db270a8SFrederic Weisbecker static DEFINE_MUTEX(blk_tree_mutex); 2602db270a8SFrederic Weisbecker 261ad5dd549SLi Zefan static void blk_trace_free(struct blk_trace *bt) 2622db270a8SFrederic Weisbecker { 2632db270a8SFrederic Weisbecker debugfs_remove(bt->msg_file); 2642db270a8SFrederic Weisbecker debugfs_remove(bt->dropped_file); 2652db270a8SFrederic Weisbecker relay_close(bt->rchan); 2662db270a8SFrederic Weisbecker free_percpu(bt->sequence); 2672db270a8SFrederic Weisbecker free_percpu(bt->msg_data); 2682db270a8SFrederic Weisbecker kfree(bt); 269ad5dd549SLi Zefan } 270ad5dd549SLi Zefan 271ad5dd549SLi Zefan static void blk_trace_cleanup(struct blk_trace *bt) 272ad5dd549SLi Zefan { 273ad5dd549SLi Zefan blk_trace_free(bt); 2742db270a8SFrederic Weisbecker if (atomic_dec_and_test(&blk_probes_ref)) 2752db270a8SFrederic Weisbecker blk_unregister_tracepoints(); 2762db270a8SFrederic Weisbecker } 2772db270a8SFrederic Weisbecker 2782db270a8SFrederic Weisbecker int blk_trace_remove(struct request_queue *q) 2792db270a8SFrederic Weisbecker { 2802db270a8SFrederic Weisbecker struct blk_trace *bt; 2812db270a8SFrederic Weisbecker 2822db270a8SFrederic Weisbecker bt = xchg(&q->blk_trace, NULL); 2832db270a8SFrederic Weisbecker if (!bt) 2842db270a8SFrederic Weisbecker return -EINVAL; 2852db270a8SFrederic Weisbecker 28655547204SLi Zefan if (bt->trace_state != Blktrace_running) 2872db270a8SFrederic Weisbecker blk_trace_cleanup(bt); 2882db270a8SFrederic Weisbecker 2892db270a8SFrederic Weisbecker return 0; 2902db270a8SFrederic Weisbecker } 2912db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_remove); 2922db270a8SFrederic Weisbecker 2932db270a8SFrederic Weisbecker static int blk_dropped_open(struct inode *inode, struct file *filp) 2942db270a8SFrederic Weisbecker { 2952db270a8SFrederic Weisbecker filp->private_data = inode->i_private; 2962db270a8SFrederic Weisbecker 2972db270a8SFrederic Weisbecker return 0; 2982db270a8SFrederic Weisbecker } 2992db270a8SFrederic Weisbecker 3002db270a8SFrederic Weisbecker static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, 3012db270a8SFrederic Weisbecker size_t count, loff_t *ppos) 3022db270a8SFrederic Weisbecker { 3032db270a8SFrederic Weisbecker struct blk_trace *bt = filp->private_data; 3042db270a8SFrederic Weisbecker char buf[16]; 3052db270a8SFrederic Weisbecker 3062db270a8SFrederic Weisbecker snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); 3072db270a8SFrederic Weisbecker 3082db270a8SFrederic Weisbecker return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); 3092db270a8SFrederic Weisbecker } 3102db270a8SFrederic Weisbecker 3112db270a8SFrederic Weisbecker static const struct file_operations blk_dropped_fops = { 3122db270a8SFrederic Weisbecker .owner = THIS_MODULE, 3132db270a8SFrederic Weisbecker .open = blk_dropped_open, 3142db270a8SFrederic Weisbecker .read = blk_dropped_read, 3152db270a8SFrederic Weisbecker }; 3162db270a8SFrederic Weisbecker 3172db270a8SFrederic Weisbecker static int blk_msg_open(struct inode *inode, struct file *filp) 3182db270a8SFrederic Weisbecker { 3192db270a8SFrederic Weisbecker filp->private_data = inode->i_private; 3202db270a8SFrederic Weisbecker 3212db270a8SFrederic Weisbecker return 0; 3222db270a8SFrederic Weisbecker } 3232db270a8SFrederic Weisbecker 3242db270a8SFrederic Weisbecker static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, 3252db270a8SFrederic Weisbecker size_t count, loff_t *ppos) 3262db270a8SFrederic Weisbecker { 3272db270a8SFrederic Weisbecker char *msg; 3282db270a8SFrederic Weisbecker struct blk_trace *bt; 3292db270a8SFrederic Weisbecker 3307635b03aSLi Zefan if (count >= BLK_TN_MAX_MSG) 3312db270a8SFrederic Weisbecker return -EINVAL; 3322db270a8SFrederic Weisbecker 333a4b3ada8SCarl Henrik Lunde msg = kmalloc(count + 1, GFP_KERNEL); 3342db270a8SFrederic Weisbecker if (msg == NULL) 3352db270a8SFrederic Weisbecker return -ENOMEM; 3362db270a8SFrederic Weisbecker 3372db270a8SFrederic Weisbecker if (copy_from_user(msg, buffer, count)) { 3382db270a8SFrederic Weisbecker kfree(msg); 3392db270a8SFrederic Weisbecker return -EFAULT; 3402db270a8SFrederic Weisbecker } 3412db270a8SFrederic Weisbecker 342a4b3ada8SCarl Henrik Lunde msg[count] = '\0'; 3432db270a8SFrederic Weisbecker bt = filp->private_data; 3442db270a8SFrederic Weisbecker __trace_note_message(bt, "%s", msg); 3452db270a8SFrederic Weisbecker kfree(msg); 3462db270a8SFrederic Weisbecker 3472db270a8SFrederic Weisbecker return count; 3482db270a8SFrederic Weisbecker } 3492db270a8SFrederic Weisbecker 3502db270a8SFrederic Weisbecker static const struct file_operations blk_msg_fops = { 3512db270a8SFrederic Weisbecker .owner = THIS_MODULE, 3522db270a8SFrederic Weisbecker .open = blk_msg_open, 3532db270a8SFrederic Weisbecker .write = blk_msg_write, 3542db270a8SFrederic Weisbecker }; 3552db270a8SFrederic Weisbecker 3562db270a8SFrederic Weisbecker /* 3572db270a8SFrederic Weisbecker * Keep track of how many times we encountered a full subbuffer, to aid 3582db270a8SFrederic Weisbecker * the user space app in telling how many lost events there were. 3592db270a8SFrederic Weisbecker */ 3602db270a8SFrederic Weisbecker static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, 3612db270a8SFrederic Weisbecker void *prev_subbuf, size_t prev_padding) 3622db270a8SFrederic Weisbecker { 3632db270a8SFrederic Weisbecker struct blk_trace *bt; 3642db270a8SFrederic Weisbecker 3652db270a8SFrederic Weisbecker if (!relay_buf_full(buf)) 3662db270a8SFrederic Weisbecker return 1; 3672db270a8SFrederic Weisbecker 3682db270a8SFrederic Weisbecker bt = buf->chan->private_data; 3692db270a8SFrederic Weisbecker atomic_inc(&bt->dropped); 3702db270a8SFrederic Weisbecker return 0; 3712db270a8SFrederic Weisbecker } 3722db270a8SFrederic Weisbecker 3732db270a8SFrederic Weisbecker static int blk_remove_buf_file_callback(struct dentry *dentry) 3742db270a8SFrederic Weisbecker { 3752db270a8SFrederic Weisbecker struct dentry *parent = dentry->d_parent; 3762db270a8SFrederic Weisbecker debugfs_remove(dentry); 3772db270a8SFrederic Weisbecker 3782db270a8SFrederic Weisbecker /* 3792db270a8SFrederic Weisbecker * this will fail for all but the last file, but that is ok. what we 3802db270a8SFrederic Weisbecker * care about is the top level buts->name directory going away, when 3812db270a8SFrederic Weisbecker * the last trace file is gone. Then we don't have to rmdir() that 3822db270a8SFrederic Weisbecker * manually on trace stop, so it nicely solves the issue with 3832db270a8SFrederic Weisbecker * force killing of running traces. 3842db270a8SFrederic Weisbecker */ 3852db270a8SFrederic Weisbecker 3862db270a8SFrederic Weisbecker debugfs_remove(parent); 3872db270a8SFrederic Weisbecker return 0; 3882db270a8SFrederic Weisbecker } 3892db270a8SFrederic Weisbecker 3902db270a8SFrederic Weisbecker static struct dentry *blk_create_buf_file_callback(const char *filename, 3912db270a8SFrederic Weisbecker struct dentry *parent, 3922db270a8SFrederic Weisbecker int mode, 3932db270a8SFrederic Weisbecker struct rchan_buf *buf, 3942db270a8SFrederic Weisbecker int *is_global) 3952db270a8SFrederic Weisbecker { 3962db270a8SFrederic Weisbecker return debugfs_create_file(filename, mode, parent, buf, 3972db270a8SFrederic Weisbecker &relay_file_operations); 3982db270a8SFrederic Weisbecker } 3992db270a8SFrederic Weisbecker 4002db270a8SFrederic Weisbecker static struct rchan_callbacks blk_relay_callbacks = { 4012db270a8SFrederic Weisbecker .subbuf_start = blk_subbuf_start_callback, 4022db270a8SFrederic Weisbecker .create_buf_file = blk_create_buf_file_callback, 4032db270a8SFrederic Weisbecker .remove_buf_file = blk_remove_buf_file_callback, 4042db270a8SFrederic Weisbecker }; 4052db270a8SFrederic Weisbecker 4069908c309SLi Zefan static void blk_trace_setup_lba(struct blk_trace *bt, 4079908c309SLi Zefan struct block_device *bdev) 4089908c309SLi Zefan { 4099908c309SLi Zefan struct hd_struct *part = NULL; 4109908c309SLi Zefan 4119908c309SLi Zefan if (bdev) 4129908c309SLi Zefan part = bdev->bd_part; 4139908c309SLi Zefan 4149908c309SLi Zefan if (part) { 4159908c309SLi Zefan bt->start_lba = part->start_sect; 4169908c309SLi Zefan bt->end_lba = part->start_sect + part->nr_sects; 4179908c309SLi Zefan } else { 4189908c309SLi Zefan bt->start_lba = 0; 4199908c309SLi Zefan bt->end_lba = -1ULL; 4209908c309SLi Zefan } 4219908c309SLi Zefan } 4229908c309SLi Zefan 4232db270a8SFrederic Weisbecker /* 4242db270a8SFrederic Weisbecker * Setup everything required to start tracing 4252db270a8SFrederic Weisbecker */ 4262db270a8SFrederic Weisbecker int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 427d0deef5bSShawn Du struct block_device *bdev, 4282db270a8SFrederic Weisbecker struct blk_user_trace_setup *buts) 4292db270a8SFrederic Weisbecker { 4302db270a8SFrederic Weisbecker struct blk_trace *old_bt, *bt = NULL; 4312db270a8SFrederic Weisbecker struct dentry *dir = NULL; 4322db270a8SFrederic Weisbecker int ret, i; 4332db270a8SFrederic Weisbecker 4342db270a8SFrederic Weisbecker if (!buts->buf_size || !buts->buf_nr) 4352db270a8SFrederic Weisbecker return -EINVAL; 4362db270a8SFrederic Weisbecker 4372db270a8SFrederic Weisbecker strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); 4382db270a8SFrederic Weisbecker buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; 4392db270a8SFrederic Weisbecker 4402db270a8SFrederic Weisbecker /* 4412db270a8SFrederic Weisbecker * some device names have larger paths - convert the slashes 4422db270a8SFrederic Weisbecker * to underscores for this to work as expected 4432db270a8SFrederic Weisbecker */ 4442db270a8SFrederic Weisbecker for (i = 0; i < strlen(buts->name); i++) 4452db270a8SFrederic Weisbecker if (buts->name[i] == '/') 4462db270a8SFrederic Weisbecker buts->name[i] = '_'; 4472db270a8SFrederic Weisbecker 4482db270a8SFrederic Weisbecker bt = kzalloc(sizeof(*bt), GFP_KERNEL); 4492db270a8SFrederic Weisbecker if (!bt) 450ad5dd549SLi Zefan return -ENOMEM; 4512db270a8SFrederic Weisbecker 452ad5dd549SLi Zefan ret = -ENOMEM; 4532db270a8SFrederic Weisbecker bt->sequence = alloc_percpu(unsigned long); 4542db270a8SFrederic Weisbecker if (!bt->sequence) 4552db270a8SFrederic Weisbecker goto err; 4562db270a8SFrederic Weisbecker 457f0ef0398SIngo Molnar bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); 4582db270a8SFrederic Weisbecker if (!bt->msg_data) 4592db270a8SFrederic Weisbecker goto err; 4602db270a8SFrederic Weisbecker 4612db270a8SFrederic Weisbecker ret = -ENOENT; 4622db270a8SFrederic Weisbecker 463b5230b56SLi Zefan mutex_lock(&blk_tree_mutex); 4642db270a8SFrederic Weisbecker if (!blk_tree_root) { 4652db270a8SFrederic Weisbecker blk_tree_root = debugfs_create_dir("block", NULL); 466b5230b56SLi Zefan if (!blk_tree_root) { 467b5230b56SLi Zefan mutex_unlock(&blk_tree_mutex); 4681a17662eSLi Zefan goto err; 4692db270a8SFrederic Weisbecker } 470b5230b56SLi Zefan } 471b5230b56SLi Zefan mutex_unlock(&blk_tree_mutex); 4722db270a8SFrederic Weisbecker 4732db270a8SFrederic Weisbecker dir = debugfs_create_dir(buts->name, blk_tree_root); 4742db270a8SFrederic Weisbecker 4752db270a8SFrederic Weisbecker if (!dir) 4762db270a8SFrederic Weisbecker goto err; 4772db270a8SFrederic Weisbecker 4782db270a8SFrederic Weisbecker bt->dir = dir; 4792db270a8SFrederic Weisbecker bt->dev = dev; 4802db270a8SFrederic Weisbecker atomic_set(&bt->dropped, 0); 4812db270a8SFrederic Weisbecker 4822db270a8SFrederic Weisbecker ret = -EIO; 4832db270a8SFrederic Weisbecker bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, 4842db270a8SFrederic Weisbecker &blk_dropped_fops); 4852db270a8SFrederic Weisbecker if (!bt->dropped_file) 4862db270a8SFrederic Weisbecker goto err; 4872db270a8SFrederic Weisbecker 4882db270a8SFrederic Weisbecker bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); 4892db270a8SFrederic Weisbecker if (!bt->msg_file) 4902db270a8SFrederic Weisbecker goto err; 4912db270a8SFrederic Weisbecker 4922db270a8SFrederic Weisbecker bt->rchan = relay_open("trace", dir, buts->buf_size, 4932db270a8SFrederic Weisbecker buts->buf_nr, &blk_relay_callbacks, bt); 4942db270a8SFrederic Weisbecker if (!bt->rchan) 4952db270a8SFrederic Weisbecker goto err; 4962db270a8SFrederic Weisbecker 4972db270a8SFrederic Weisbecker bt->act_mask = buts->act_mask; 4982db270a8SFrederic Weisbecker if (!bt->act_mask) 4992db270a8SFrederic Weisbecker bt->act_mask = (u16) -1; 5002db270a8SFrederic Weisbecker 5019908c309SLi Zefan blk_trace_setup_lba(bt, bdev); 5022db270a8SFrederic Weisbecker 503d0deef5bSShawn Du /* overwrite with user settings */ 504d0deef5bSShawn Du if (buts->start_lba) 505d0deef5bSShawn Du bt->start_lba = buts->start_lba; 506d0deef5bSShawn Du if (buts->end_lba) 507d0deef5bSShawn Du bt->end_lba = buts->end_lba; 508d0deef5bSShawn Du 5092db270a8SFrederic Weisbecker bt->pid = buts->pid; 5102db270a8SFrederic Weisbecker bt->trace_state = Blktrace_setup; 5112db270a8SFrederic Weisbecker 5122db270a8SFrederic Weisbecker ret = -EBUSY; 5132db270a8SFrederic Weisbecker old_bt = xchg(&q->blk_trace, bt); 5142db270a8SFrederic Weisbecker if (old_bt) { 5152db270a8SFrederic Weisbecker (void) xchg(&q->blk_trace, old_bt); 5162db270a8SFrederic Weisbecker goto err; 5172db270a8SFrederic Weisbecker } 5182db270a8SFrederic Weisbecker 51917ba97e3SLi Zefan if (atomic_inc_return(&blk_probes_ref) == 1) 520cbe28296SLi Zefan blk_register_tracepoints(); 521cbe28296SLi Zefan 5222db270a8SFrederic Weisbecker return 0; 5232db270a8SFrederic Weisbecker err: 524ad5dd549SLi Zefan blk_trace_free(bt); 5252db270a8SFrederic Weisbecker return ret; 5262db270a8SFrederic Weisbecker } 5272db270a8SFrederic Weisbecker 5282db270a8SFrederic Weisbecker int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 529d0deef5bSShawn Du struct block_device *bdev, 5302db270a8SFrederic Weisbecker char __user *arg) 5312db270a8SFrederic Weisbecker { 5322db270a8SFrederic Weisbecker struct blk_user_trace_setup buts; 5332db270a8SFrederic Weisbecker int ret; 5342db270a8SFrederic Weisbecker 5352db270a8SFrederic Weisbecker ret = copy_from_user(&buts, arg, sizeof(buts)); 5362db270a8SFrederic Weisbecker if (ret) 5372db270a8SFrederic Weisbecker return -EFAULT; 5382db270a8SFrederic Weisbecker 539d0deef5bSShawn Du ret = do_blk_trace_setup(q, name, dev, bdev, &buts); 5402db270a8SFrederic Weisbecker if (ret) 5412db270a8SFrederic Weisbecker return ret; 5422db270a8SFrederic Weisbecker 5432db270a8SFrederic Weisbecker if (copy_to_user(arg, &buts, sizeof(buts))) 5442db270a8SFrederic Weisbecker return -EFAULT; 5452db270a8SFrederic Weisbecker 5462db270a8SFrederic Weisbecker return 0; 5472db270a8SFrederic Weisbecker } 5482db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_setup); 5492db270a8SFrederic Weisbecker 5502db270a8SFrederic Weisbecker int blk_trace_startstop(struct request_queue *q, int start) 5512db270a8SFrederic Weisbecker { 5522db270a8SFrederic Weisbecker int ret; 5532db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 5542db270a8SFrederic Weisbecker 5552db270a8SFrederic Weisbecker if (bt == NULL) 5562db270a8SFrederic Weisbecker return -EINVAL; 5572db270a8SFrederic Weisbecker 5582db270a8SFrederic Weisbecker /* 5592db270a8SFrederic Weisbecker * For starting a trace, we can transition from a setup or stopped 5602db270a8SFrederic Weisbecker * trace. For stopping a trace, the state must be running 5612db270a8SFrederic Weisbecker */ 5622db270a8SFrederic Weisbecker ret = -EINVAL; 5632db270a8SFrederic Weisbecker if (start) { 5642db270a8SFrederic Weisbecker if (bt->trace_state == Blktrace_setup || 5652db270a8SFrederic Weisbecker bt->trace_state == Blktrace_stopped) { 5662db270a8SFrederic Weisbecker blktrace_seq++; 5672db270a8SFrederic Weisbecker smp_mb(); 5682db270a8SFrederic Weisbecker bt->trace_state = Blktrace_running; 5692db270a8SFrederic Weisbecker 5702db270a8SFrederic Weisbecker trace_note_time(bt); 5712db270a8SFrederic Weisbecker ret = 0; 5722db270a8SFrederic Weisbecker } 5732db270a8SFrederic Weisbecker } else { 5742db270a8SFrederic Weisbecker if (bt->trace_state == Blktrace_running) { 5752db270a8SFrederic Weisbecker bt->trace_state = Blktrace_stopped; 5762db270a8SFrederic Weisbecker relay_flush(bt->rchan); 5772db270a8SFrederic Weisbecker ret = 0; 5782db270a8SFrederic Weisbecker } 5792db270a8SFrederic Weisbecker } 5802db270a8SFrederic Weisbecker 5812db270a8SFrederic Weisbecker return ret; 5822db270a8SFrederic Weisbecker } 5832db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_startstop); 5842db270a8SFrederic Weisbecker 5852db270a8SFrederic Weisbecker /** 5862db270a8SFrederic Weisbecker * blk_trace_ioctl: - handle the ioctls associated with tracing 5872db270a8SFrederic Weisbecker * @bdev: the block device 5882db270a8SFrederic Weisbecker * @cmd: the ioctl cmd 5892db270a8SFrederic Weisbecker * @arg: the argument data, if any 5902db270a8SFrederic Weisbecker * 5912db270a8SFrederic Weisbecker **/ 5922db270a8SFrederic Weisbecker int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) 5932db270a8SFrederic Weisbecker { 5942db270a8SFrederic Weisbecker struct request_queue *q; 5952db270a8SFrederic Weisbecker int ret, start = 0; 5962db270a8SFrederic Weisbecker char b[BDEVNAME_SIZE]; 5972db270a8SFrederic Weisbecker 5982db270a8SFrederic Weisbecker q = bdev_get_queue(bdev); 5992db270a8SFrederic Weisbecker if (!q) 6002db270a8SFrederic Weisbecker return -ENXIO; 6012db270a8SFrederic Weisbecker 6022db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 6032db270a8SFrederic Weisbecker 6042db270a8SFrederic Weisbecker switch (cmd) { 6052db270a8SFrederic Weisbecker case BLKTRACESETUP: 6062db270a8SFrederic Weisbecker bdevname(bdev, b); 607d0deef5bSShawn Du ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); 6082db270a8SFrederic Weisbecker break; 6092db270a8SFrederic Weisbecker case BLKTRACESTART: 6102db270a8SFrederic Weisbecker start = 1; 6112db270a8SFrederic Weisbecker case BLKTRACESTOP: 6122db270a8SFrederic Weisbecker ret = blk_trace_startstop(q, start); 6132db270a8SFrederic Weisbecker break; 6142db270a8SFrederic Weisbecker case BLKTRACETEARDOWN: 6152db270a8SFrederic Weisbecker ret = blk_trace_remove(q); 6162db270a8SFrederic Weisbecker break; 6172db270a8SFrederic Weisbecker default: 6182db270a8SFrederic Weisbecker ret = -ENOTTY; 6192db270a8SFrederic Weisbecker break; 6202db270a8SFrederic Weisbecker } 6212db270a8SFrederic Weisbecker 6222db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 6232db270a8SFrederic Weisbecker return ret; 6242db270a8SFrederic Weisbecker } 6252db270a8SFrederic Weisbecker 6262db270a8SFrederic Weisbecker /** 6272db270a8SFrederic Weisbecker * blk_trace_shutdown: - stop and cleanup trace structures 6282db270a8SFrederic Weisbecker * @q: the request queue associated with the device 6292db270a8SFrederic Weisbecker * 6302db270a8SFrederic Weisbecker **/ 6312db270a8SFrederic Weisbecker void blk_trace_shutdown(struct request_queue *q) 6322db270a8SFrederic Weisbecker { 6332db270a8SFrederic Weisbecker if (q->blk_trace) { 6342db270a8SFrederic Weisbecker blk_trace_startstop(q, 0); 6352db270a8SFrederic Weisbecker blk_trace_remove(q); 6362db270a8SFrederic Weisbecker } 6372db270a8SFrederic Weisbecker } 6382db270a8SFrederic Weisbecker 6392db270a8SFrederic Weisbecker /* 6402db270a8SFrederic Weisbecker * blktrace probes 6412db270a8SFrederic Weisbecker */ 6422db270a8SFrederic Weisbecker 6432db270a8SFrederic Weisbecker /** 6442db270a8SFrederic Weisbecker * blk_add_trace_rq - Add a trace for a request oriented action 6452db270a8SFrederic Weisbecker * @q: queue the io is for 6462db270a8SFrederic Weisbecker * @rq: the source request 6472db270a8SFrederic Weisbecker * @what: the action 6482db270a8SFrederic Weisbecker * 6492db270a8SFrederic Weisbecker * Description: 6502db270a8SFrederic Weisbecker * Records an action against a request. Will log the bio offset + size. 6512db270a8SFrederic Weisbecker * 6522db270a8SFrederic Weisbecker **/ 6532db270a8SFrederic Weisbecker static void blk_add_trace_rq(struct request_queue *q, struct request *rq, 6542db270a8SFrederic Weisbecker u32 what) 6552db270a8SFrederic Weisbecker { 6562db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 6572db270a8SFrederic Weisbecker int rw = rq->cmd_flags & 0x03; 6582db270a8SFrederic Weisbecker 6592db270a8SFrederic Weisbecker if (likely(!bt)) 6602db270a8SFrederic Weisbecker return; 6612db270a8SFrederic Weisbecker 6622db270a8SFrederic Weisbecker if (blk_discard_rq(rq)) 6632db270a8SFrederic Weisbecker rw |= (1 << BIO_RW_DISCARD); 6642db270a8SFrederic Weisbecker 6652db270a8SFrederic Weisbecker if (blk_pc_request(rq)) { 6662db270a8SFrederic Weisbecker what |= BLK_TC_ACT(BLK_TC_PC); 6672db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, 668e2494e1bSLi Zefan rq->cmd_len, rq->cmd); 6692db270a8SFrederic Weisbecker } else { 6702db270a8SFrederic Weisbecker what |= BLK_TC_ACT(BLK_TC_FS); 6712db270a8SFrederic Weisbecker __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, 6722db270a8SFrederic Weisbecker rw, what, rq->errors, 0, NULL); 6732db270a8SFrederic Weisbecker } 6742db270a8SFrederic Weisbecker } 6752db270a8SFrederic Weisbecker 6762db270a8SFrederic Weisbecker static void blk_add_trace_rq_abort(struct request_queue *q, struct request *rq) 6772db270a8SFrederic Weisbecker { 6782db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_ABORT); 6792db270a8SFrederic Weisbecker } 6802db270a8SFrederic Weisbecker 6812db270a8SFrederic Weisbecker static void blk_add_trace_rq_insert(struct request_queue *q, struct request *rq) 6822db270a8SFrederic Weisbecker { 6832db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_INSERT); 6842db270a8SFrederic Weisbecker } 6852db270a8SFrederic Weisbecker 6862db270a8SFrederic Weisbecker static void blk_add_trace_rq_issue(struct request_queue *q, struct request *rq) 6872db270a8SFrederic Weisbecker { 6882db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_ISSUE); 6892db270a8SFrederic Weisbecker } 6902db270a8SFrederic Weisbecker 6912db270a8SFrederic Weisbecker static void blk_add_trace_rq_requeue(struct request_queue *q, 6922db270a8SFrederic Weisbecker struct request *rq) 6932db270a8SFrederic Weisbecker { 6942db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); 6952db270a8SFrederic Weisbecker } 6962db270a8SFrederic Weisbecker 6972db270a8SFrederic Weisbecker static void blk_add_trace_rq_complete(struct request_queue *q, 6982db270a8SFrederic Weisbecker struct request *rq) 6992db270a8SFrederic Weisbecker { 7002db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); 7012db270a8SFrederic Weisbecker } 7022db270a8SFrederic Weisbecker 7032db270a8SFrederic Weisbecker /** 7042db270a8SFrederic Weisbecker * blk_add_trace_bio - Add a trace for a bio oriented action 7052db270a8SFrederic Weisbecker * @q: queue the io is for 7062db270a8SFrederic Weisbecker * @bio: the source bio 7072db270a8SFrederic Weisbecker * @what: the action 7082db270a8SFrederic Weisbecker * 7092db270a8SFrederic Weisbecker * Description: 7102db270a8SFrederic Weisbecker * Records an action against a bio. Will log the bio offset + size. 7112db270a8SFrederic Weisbecker * 7122db270a8SFrederic Weisbecker **/ 7132db270a8SFrederic Weisbecker static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, 7142db270a8SFrederic Weisbecker u32 what) 7152db270a8SFrederic Weisbecker { 7162db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7172db270a8SFrederic Weisbecker 7182db270a8SFrederic Weisbecker if (likely(!bt)) 7192db270a8SFrederic Weisbecker return; 7202db270a8SFrederic Weisbecker 7212db270a8SFrederic Weisbecker __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, 7222db270a8SFrederic Weisbecker !bio_flagged(bio, BIO_UPTODATE), 0, NULL); 7232db270a8SFrederic Weisbecker } 7242db270a8SFrederic Weisbecker 7252db270a8SFrederic Weisbecker static void blk_add_trace_bio_bounce(struct request_queue *q, struct bio *bio) 7262db270a8SFrederic Weisbecker { 7272db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); 7282db270a8SFrederic Weisbecker } 7292db270a8SFrederic Weisbecker 7302db270a8SFrederic Weisbecker static void blk_add_trace_bio_complete(struct request_queue *q, struct bio *bio) 7312db270a8SFrederic Weisbecker { 7322db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); 7332db270a8SFrederic Weisbecker } 7342db270a8SFrederic Weisbecker 7352db270a8SFrederic Weisbecker static void blk_add_trace_bio_backmerge(struct request_queue *q, 7362db270a8SFrederic Weisbecker struct bio *bio) 7372db270a8SFrederic Weisbecker { 7382db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); 7392db270a8SFrederic Weisbecker } 7402db270a8SFrederic Weisbecker 7412db270a8SFrederic Weisbecker static void blk_add_trace_bio_frontmerge(struct request_queue *q, 7422db270a8SFrederic Weisbecker struct bio *bio) 7432db270a8SFrederic Weisbecker { 7442db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); 7452db270a8SFrederic Weisbecker } 7462db270a8SFrederic Weisbecker 7472db270a8SFrederic Weisbecker static void blk_add_trace_bio_queue(struct request_queue *q, struct bio *bio) 7482db270a8SFrederic Weisbecker { 7492db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_QUEUE); 7502db270a8SFrederic Weisbecker } 7512db270a8SFrederic Weisbecker 7522db270a8SFrederic Weisbecker static void blk_add_trace_getrq(struct request_queue *q, 7532db270a8SFrederic Weisbecker struct bio *bio, int rw) 7542db270a8SFrederic Weisbecker { 7552db270a8SFrederic Weisbecker if (bio) 7562db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_GETRQ); 7572db270a8SFrederic Weisbecker else { 7582db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7592db270a8SFrederic Weisbecker 7602db270a8SFrederic Weisbecker if (bt) 7612db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); 7622db270a8SFrederic Weisbecker } 7632db270a8SFrederic Weisbecker } 7642db270a8SFrederic Weisbecker 7652db270a8SFrederic Weisbecker 7662db270a8SFrederic Weisbecker static void blk_add_trace_sleeprq(struct request_queue *q, 7672db270a8SFrederic Weisbecker struct bio *bio, int rw) 7682db270a8SFrederic Weisbecker { 7692db270a8SFrederic Weisbecker if (bio) 7702db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); 7712db270a8SFrederic Weisbecker else { 7722db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7732db270a8SFrederic Weisbecker 7742db270a8SFrederic Weisbecker if (bt) 7752db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, 7762db270a8SFrederic Weisbecker 0, 0, NULL); 7772db270a8SFrederic Weisbecker } 7782db270a8SFrederic Weisbecker } 7792db270a8SFrederic Weisbecker 7802db270a8SFrederic Weisbecker static void blk_add_trace_plug(struct request_queue *q) 7812db270a8SFrederic Weisbecker { 7822db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7832db270a8SFrederic Weisbecker 7842db270a8SFrederic Weisbecker if (bt) 7852db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); 7862db270a8SFrederic Weisbecker } 7872db270a8SFrederic Weisbecker 7882db270a8SFrederic Weisbecker static void blk_add_trace_unplug_io(struct request_queue *q) 7892db270a8SFrederic Weisbecker { 7902db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7912db270a8SFrederic Weisbecker 7922db270a8SFrederic Weisbecker if (bt) { 7932db270a8SFrederic Weisbecker unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; 7942db270a8SFrederic Weisbecker __be64 rpdu = cpu_to_be64(pdu); 7952db270a8SFrederic Weisbecker 7962db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, 7972db270a8SFrederic Weisbecker sizeof(rpdu), &rpdu); 7982db270a8SFrederic Weisbecker } 7992db270a8SFrederic Weisbecker } 8002db270a8SFrederic Weisbecker 8012db270a8SFrederic Weisbecker static void blk_add_trace_unplug_timer(struct request_queue *q) 8022db270a8SFrederic Weisbecker { 8032db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8042db270a8SFrederic Weisbecker 8052db270a8SFrederic Weisbecker if (bt) { 8062db270a8SFrederic Weisbecker unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; 8072db270a8SFrederic Weisbecker __be64 rpdu = cpu_to_be64(pdu); 8082db270a8SFrederic Weisbecker 8092db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, 8102db270a8SFrederic Weisbecker sizeof(rpdu), &rpdu); 8112db270a8SFrederic Weisbecker } 8122db270a8SFrederic Weisbecker } 8132db270a8SFrederic Weisbecker 8142db270a8SFrederic Weisbecker static void blk_add_trace_split(struct request_queue *q, struct bio *bio, 8152db270a8SFrederic Weisbecker unsigned int pdu) 8162db270a8SFrederic Weisbecker { 8172db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8182db270a8SFrederic Weisbecker 8192db270a8SFrederic Weisbecker if (bt) { 8202db270a8SFrederic Weisbecker __be64 rpdu = cpu_to_be64(pdu); 8212db270a8SFrederic Weisbecker 8222db270a8SFrederic Weisbecker __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, 8232db270a8SFrederic Weisbecker BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), 8242db270a8SFrederic Weisbecker sizeof(rpdu), &rpdu); 8252db270a8SFrederic Weisbecker } 8262db270a8SFrederic Weisbecker } 8272db270a8SFrederic Weisbecker 8282db270a8SFrederic Weisbecker /** 8292db270a8SFrederic Weisbecker * blk_add_trace_remap - Add a trace for a remap operation 8302db270a8SFrederic Weisbecker * @q: queue the io is for 8312db270a8SFrederic Weisbecker * @bio: the source bio 8322db270a8SFrederic Weisbecker * @dev: target device 833a42aaa3bSAlan D. Brunelle * @from: source sector 8342db270a8SFrederic Weisbecker * 8352db270a8SFrederic Weisbecker * Description: 8362db270a8SFrederic Weisbecker * Device mapper or raid target sometimes need to split a bio because 8372db270a8SFrederic Weisbecker * it spans a stripe (or similar). Add a trace for that action. 8382db270a8SFrederic Weisbecker * 8392db270a8SFrederic Weisbecker **/ 8402db270a8SFrederic Weisbecker static void blk_add_trace_remap(struct request_queue *q, struct bio *bio, 84122a7c31aSAlan D. Brunelle dev_t dev, sector_t from) 8422db270a8SFrederic Weisbecker { 8432db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8442db270a8SFrederic Weisbecker struct blk_io_trace_remap r; 8452db270a8SFrederic Weisbecker 8462db270a8SFrederic Weisbecker if (likely(!bt)) 8472db270a8SFrederic Weisbecker return; 8482db270a8SFrederic Weisbecker 849a42aaa3bSAlan D. Brunelle r.device_from = cpu_to_be32(dev); 850a42aaa3bSAlan D. Brunelle r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); 851a42aaa3bSAlan D. Brunelle r.sector_from = cpu_to_be64(from); 8522db270a8SFrederic Weisbecker 85322a7c31aSAlan D. Brunelle __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, 85422a7c31aSAlan D. Brunelle BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), 85522a7c31aSAlan D. Brunelle sizeof(r), &r); 8562db270a8SFrederic Weisbecker } 8572db270a8SFrederic Weisbecker 8582db270a8SFrederic Weisbecker /** 8592db270a8SFrederic Weisbecker * blk_add_driver_data - Add binary message with driver-specific data 8602db270a8SFrederic Weisbecker * @q: queue the io is for 8612db270a8SFrederic Weisbecker * @rq: io request 8622db270a8SFrederic Weisbecker * @data: driver-specific data 8632db270a8SFrederic Weisbecker * @len: length of driver-specific data 8642db270a8SFrederic Weisbecker * 8652db270a8SFrederic Weisbecker * Description: 8662db270a8SFrederic Weisbecker * Some drivers might want to write driver-specific data per request. 8672db270a8SFrederic Weisbecker * 8682db270a8SFrederic Weisbecker **/ 8692db270a8SFrederic Weisbecker void blk_add_driver_data(struct request_queue *q, 8702db270a8SFrederic Weisbecker struct request *rq, 8712db270a8SFrederic Weisbecker void *data, size_t len) 8722db270a8SFrederic Weisbecker { 8732db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8742db270a8SFrederic Weisbecker 8752db270a8SFrederic Weisbecker if (likely(!bt)) 8762db270a8SFrederic Weisbecker return; 8772db270a8SFrederic Weisbecker 8782db270a8SFrederic Weisbecker if (blk_pc_request(rq)) 8792db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, rq->data_len, 0, BLK_TA_DRV_DATA, 8802db270a8SFrederic Weisbecker rq->errors, len, data); 8812db270a8SFrederic Weisbecker else 8822db270a8SFrederic Weisbecker __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, 8832db270a8SFrederic Weisbecker 0, BLK_TA_DRV_DATA, rq->errors, len, data); 8842db270a8SFrederic Weisbecker } 8852db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_add_driver_data); 8862db270a8SFrederic Weisbecker 8873c289ba7SLi Zefan static void blk_register_tracepoints(void) 8882db270a8SFrederic Weisbecker { 8892db270a8SFrederic Weisbecker int ret; 8902db270a8SFrederic Weisbecker 8912db270a8SFrederic Weisbecker ret = register_trace_block_rq_abort(blk_add_trace_rq_abort); 8922db270a8SFrederic Weisbecker WARN_ON(ret); 8932db270a8SFrederic Weisbecker ret = register_trace_block_rq_insert(blk_add_trace_rq_insert); 8942db270a8SFrederic Weisbecker WARN_ON(ret); 8952db270a8SFrederic Weisbecker ret = register_trace_block_rq_issue(blk_add_trace_rq_issue); 8962db270a8SFrederic Weisbecker WARN_ON(ret); 8972db270a8SFrederic Weisbecker ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue); 8982db270a8SFrederic Weisbecker WARN_ON(ret); 8992db270a8SFrederic Weisbecker ret = register_trace_block_rq_complete(blk_add_trace_rq_complete); 9002db270a8SFrederic Weisbecker WARN_ON(ret); 9012db270a8SFrederic Weisbecker ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce); 9022db270a8SFrederic Weisbecker WARN_ON(ret); 9032db270a8SFrederic Weisbecker ret = register_trace_block_bio_complete(blk_add_trace_bio_complete); 9042db270a8SFrederic Weisbecker WARN_ON(ret); 9052db270a8SFrederic Weisbecker ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); 9062db270a8SFrederic Weisbecker WARN_ON(ret); 9072db270a8SFrederic Weisbecker ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); 9082db270a8SFrederic Weisbecker WARN_ON(ret); 9092db270a8SFrederic Weisbecker ret = register_trace_block_bio_queue(blk_add_trace_bio_queue); 9102db270a8SFrederic Weisbecker WARN_ON(ret); 9112db270a8SFrederic Weisbecker ret = register_trace_block_getrq(blk_add_trace_getrq); 9122db270a8SFrederic Weisbecker WARN_ON(ret); 9132db270a8SFrederic Weisbecker ret = register_trace_block_sleeprq(blk_add_trace_sleeprq); 9142db270a8SFrederic Weisbecker WARN_ON(ret); 9152db270a8SFrederic Weisbecker ret = register_trace_block_plug(blk_add_trace_plug); 9162db270a8SFrederic Weisbecker WARN_ON(ret); 9172db270a8SFrederic Weisbecker ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer); 9182db270a8SFrederic Weisbecker WARN_ON(ret); 9192db270a8SFrederic Weisbecker ret = register_trace_block_unplug_io(blk_add_trace_unplug_io); 9202db270a8SFrederic Weisbecker WARN_ON(ret); 9212db270a8SFrederic Weisbecker ret = register_trace_block_split(blk_add_trace_split); 9222db270a8SFrederic Weisbecker WARN_ON(ret); 9232db270a8SFrederic Weisbecker ret = register_trace_block_remap(blk_add_trace_remap); 9242db270a8SFrederic Weisbecker WARN_ON(ret); 9252db270a8SFrederic Weisbecker } 9262db270a8SFrederic Weisbecker 9272db270a8SFrederic Weisbecker static void blk_unregister_tracepoints(void) 9282db270a8SFrederic Weisbecker { 9292db270a8SFrederic Weisbecker unregister_trace_block_remap(blk_add_trace_remap); 9302db270a8SFrederic Weisbecker unregister_trace_block_split(blk_add_trace_split); 9312db270a8SFrederic Weisbecker unregister_trace_block_unplug_io(blk_add_trace_unplug_io); 9322db270a8SFrederic Weisbecker unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer); 9332db270a8SFrederic Weisbecker unregister_trace_block_plug(blk_add_trace_plug); 9342db270a8SFrederic Weisbecker unregister_trace_block_sleeprq(blk_add_trace_sleeprq); 9352db270a8SFrederic Weisbecker unregister_trace_block_getrq(blk_add_trace_getrq); 9362db270a8SFrederic Weisbecker unregister_trace_block_bio_queue(blk_add_trace_bio_queue); 9372db270a8SFrederic Weisbecker unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); 9382db270a8SFrederic Weisbecker unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); 9392db270a8SFrederic Weisbecker unregister_trace_block_bio_complete(blk_add_trace_bio_complete); 9402db270a8SFrederic Weisbecker unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce); 9412db270a8SFrederic Weisbecker unregister_trace_block_rq_complete(blk_add_trace_rq_complete); 9422db270a8SFrederic Weisbecker unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue); 9432db270a8SFrederic Weisbecker unregister_trace_block_rq_issue(blk_add_trace_rq_issue); 9442db270a8SFrederic Weisbecker unregister_trace_block_rq_insert(blk_add_trace_rq_insert); 9452db270a8SFrederic Weisbecker unregister_trace_block_rq_abort(blk_add_trace_rq_abort); 9462db270a8SFrederic Weisbecker 9472db270a8SFrederic Weisbecker tracepoint_synchronize_unregister(); 9482db270a8SFrederic Weisbecker } 9492db270a8SFrederic Weisbecker 9502db270a8SFrederic Weisbecker /* 9512db270a8SFrederic Weisbecker * struct blk_io_tracer formatting routines 9522db270a8SFrederic Weisbecker */ 9532db270a8SFrederic Weisbecker 9542db270a8SFrederic Weisbecker static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) 9552db270a8SFrederic Weisbecker { 9562db270a8SFrederic Weisbecker int i = 0; 95765796348SLi Zefan int tc = t->action >> BLK_TC_SHIFT; 9582db270a8SFrederic Weisbecker 95918cea459SLi Zefan if (t->action == BLK_TN_MESSAGE) { 96018cea459SLi Zefan rwbs[i++] = 'N'; 96118cea459SLi Zefan goto out; 96218cea459SLi Zefan } 96318cea459SLi Zefan 96465796348SLi Zefan if (tc & BLK_TC_DISCARD) 9652db270a8SFrederic Weisbecker rwbs[i++] = 'D'; 96665796348SLi Zefan else if (tc & BLK_TC_WRITE) 9672db270a8SFrederic Weisbecker rwbs[i++] = 'W'; 9682db270a8SFrederic Weisbecker else if (t->bytes) 9692db270a8SFrederic Weisbecker rwbs[i++] = 'R'; 9702db270a8SFrederic Weisbecker else 9712db270a8SFrederic Weisbecker rwbs[i++] = 'N'; 9722db270a8SFrederic Weisbecker 97365796348SLi Zefan if (tc & BLK_TC_AHEAD) 9742db270a8SFrederic Weisbecker rwbs[i++] = 'A'; 97565796348SLi Zefan if (tc & BLK_TC_BARRIER) 9762db270a8SFrederic Weisbecker rwbs[i++] = 'B'; 97765796348SLi Zefan if (tc & BLK_TC_SYNC) 9782db270a8SFrederic Weisbecker rwbs[i++] = 'S'; 97965796348SLi Zefan if (tc & BLK_TC_META) 9802db270a8SFrederic Weisbecker rwbs[i++] = 'M'; 98118cea459SLi Zefan out: 9822db270a8SFrederic Weisbecker rwbs[i] = '\0'; 9832db270a8SFrederic Weisbecker } 9842db270a8SFrederic Weisbecker 9852db270a8SFrederic Weisbecker static inline 9862db270a8SFrederic Weisbecker const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) 9872db270a8SFrederic Weisbecker { 9882db270a8SFrederic Weisbecker return (const struct blk_io_trace *)ent; 9892db270a8SFrederic Weisbecker } 9902db270a8SFrederic Weisbecker 9912db270a8SFrederic Weisbecker static inline const void *pdu_start(const struct trace_entry *ent) 9922db270a8SFrederic Weisbecker { 9932db270a8SFrederic Weisbecker return te_blk_io_trace(ent) + 1; 9942db270a8SFrederic Weisbecker } 9952db270a8SFrederic Weisbecker 99666de7792SLi Zefan static inline u32 t_action(const struct trace_entry *ent) 99766de7792SLi Zefan { 99866de7792SLi Zefan return te_blk_io_trace(ent)->action; 99966de7792SLi Zefan } 100066de7792SLi Zefan 100166de7792SLi Zefan static inline u32 t_bytes(const struct trace_entry *ent) 100266de7792SLi Zefan { 100366de7792SLi Zefan return te_blk_io_trace(ent)->bytes; 100466de7792SLi Zefan } 100566de7792SLi Zefan 10062db270a8SFrederic Weisbecker static inline u32 t_sec(const struct trace_entry *ent) 10072db270a8SFrederic Weisbecker { 10082db270a8SFrederic Weisbecker return te_blk_io_trace(ent)->bytes >> 9; 10092db270a8SFrederic Weisbecker } 10102db270a8SFrederic Weisbecker 10112db270a8SFrederic Weisbecker static inline unsigned long long t_sector(const struct trace_entry *ent) 10122db270a8SFrederic Weisbecker { 10132db270a8SFrederic Weisbecker return te_blk_io_trace(ent)->sector; 10142db270a8SFrederic Weisbecker } 10152db270a8SFrederic Weisbecker 10162db270a8SFrederic Weisbecker static inline __u16 t_error(const struct trace_entry *ent) 10172db270a8SFrederic Weisbecker { 1018e0dc81beSLi Zefan return te_blk_io_trace(ent)->error; 10192db270a8SFrederic Weisbecker } 10202db270a8SFrederic Weisbecker 10212db270a8SFrederic Weisbecker static __u64 get_pdu_int(const struct trace_entry *ent) 10222db270a8SFrederic Weisbecker { 10232db270a8SFrederic Weisbecker const __u64 *val = pdu_start(ent); 10242db270a8SFrederic Weisbecker return be64_to_cpu(*val); 10252db270a8SFrederic Weisbecker } 10262db270a8SFrederic Weisbecker 10272db270a8SFrederic Weisbecker static void get_pdu_remap(const struct trace_entry *ent, 10282db270a8SFrederic Weisbecker struct blk_io_trace_remap *r) 10292db270a8SFrederic Weisbecker { 10302db270a8SFrederic Weisbecker const struct blk_io_trace_remap *__r = pdu_start(ent); 1031a42aaa3bSAlan D. Brunelle __u64 sector_from = __r->sector_from; 10322db270a8SFrederic Weisbecker 10332db270a8SFrederic Weisbecker r->device_from = be32_to_cpu(__r->device_from); 1034a42aaa3bSAlan D. Brunelle r->device_to = be32_to_cpu(__r->device_to); 1035a42aaa3bSAlan D. Brunelle r->sector_from = be64_to_cpu(sector_from); 10362db270a8SFrederic Weisbecker } 10372db270a8SFrederic Weisbecker 1038b6a4b0c3SLi Zefan typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); 1039b6a4b0c3SLi Zefan 1040b6a4b0c3SLi Zefan static int blk_log_action_classic(struct trace_iterator *iter, const char *act) 10412db270a8SFrederic Weisbecker { 10422db270a8SFrederic Weisbecker char rwbs[6]; 104335ac51bfSLi Zefan unsigned long long ts = iter->ts; 104435ac51bfSLi Zefan unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); 10452db270a8SFrederic Weisbecker unsigned secs = (unsigned long)ts; 1046b6a4b0c3SLi Zefan const struct blk_io_trace *t = te_blk_io_trace(iter->ent); 10472db270a8SFrederic Weisbecker 10482db270a8SFrederic Weisbecker fill_rwbs(rwbs, t); 10492db270a8SFrederic Weisbecker 10502db270a8SFrederic Weisbecker return trace_seq_printf(&iter->seq, 105135ac51bfSLi Zefan "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ", 10522db270a8SFrederic Weisbecker MAJOR(t->device), MINOR(t->device), iter->cpu, 1053b6a4b0c3SLi Zefan secs, nsec_rem, iter->ent->pid, act, rwbs); 10542db270a8SFrederic Weisbecker } 10552db270a8SFrederic Weisbecker 1056b6a4b0c3SLi Zefan static int blk_log_action(struct trace_iterator *iter, const char *act) 10572db270a8SFrederic Weisbecker { 10582db270a8SFrederic Weisbecker char rwbs[6]; 1059b6a4b0c3SLi Zefan const struct blk_io_trace *t = te_blk_io_trace(iter->ent); 1060b6a4b0c3SLi Zefan 10612db270a8SFrederic Weisbecker fill_rwbs(rwbs, t); 1062b6a4b0c3SLi Zefan return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ", 10632db270a8SFrederic Weisbecker MAJOR(t->device), MINOR(t->device), act, rwbs); 10642db270a8SFrederic Weisbecker } 10652db270a8SFrederic Weisbecker 106666de7792SLi Zefan static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent) 106766de7792SLi Zefan { 106804986257SLi Zefan const unsigned char *pdu_buf; 106966de7792SLi Zefan int pdu_len; 107066de7792SLi Zefan int i, end, ret; 107166de7792SLi Zefan 107266de7792SLi Zefan pdu_buf = pdu_start(ent); 107366de7792SLi Zefan pdu_len = te_blk_io_trace(ent)->pdu_len; 107466de7792SLi Zefan 107566de7792SLi Zefan if (!pdu_len) 107666de7792SLi Zefan return 1; 107766de7792SLi Zefan 107866de7792SLi Zefan /* find the last zero that needs to be printed */ 107966de7792SLi Zefan for (end = pdu_len - 1; end >= 0; end--) 108066de7792SLi Zefan if (pdu_buf[end]) 108166de7792SLi Zefan break; 108266de7792SLi Zefan end++; 108366de7792SLi Zefan 108466de7792SLi Zefan if (!trace_seq_putc(s, '(')) 108566de7792SLi Zefan return 0; 108666de7792SLi Zefan 108766de7792SLi Zefan for (i = 0; i < pdu_len; i++) { 108866de7792SLi Zefan 108966de7792SLi Zefan ret = trace_seq_printf(s, "%s%02x", 109066de7792SLi Zefan i == 0 ? "" : " ", pdu_buf[i]); 109166de7792SLi Zefan if (!ret) 109266de7792SLi Zefan return ret; 109366de7792SLi Zefan 109466de7792SLi Zefan /* 109566de7792SLi Zefan * stop when the rest is just zeroes and indicate so 109666de7792SLi Zefan * with a ".." appended 109766de7792SLi Zefan */ 109866de7792SLi Zefan if (i == end && end != pdu_len - 1) 109966de7792SLi Zefan return trace_seq_puts(s, " ..) "); 110066de7792SLi Zefan } 110166de7792SLi Zefan 110266de7792SLi Zefan return trace_seq_puts(s, ") "); 110366de7792SLi Zefan } 110466de7792SLi Zefan 11052db270a8SFrederic Weisbecker static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) 11062db270a8SFrederic Weisbecker { 11074ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 11084ca53085SSteven Rostedt 11094ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 11102db270a8SFrederic Weisbecker 111166de7792SLi Zefan if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { 111266de7792SLi Zefan int ret; 111366de7792SLi Zefan 111466de7792SLi Zefan ret = trace_seq_printf(s, "%u ", t_bytes(ent)); 111566de7792SLi Zefan if (!ret) 111666de7792SLi Zefan return 0; 111766de7792SLi Zefan ret = blk_log_dump_pdu(s, ent); 111866de7792SLi Zefan if (!ret) 111966de7792SLi Zefan return 0; 112066de7792SLi Zefan return trace_seq_printf(s, "[%s]\n", cmd); 112166de7792SLi Zefan } else { 11222db270a8SFrederic Weisbecker if (t_sec(ent)) 11232db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu + %u [%s]\n", 11242db270a8SFrederic Weisbecker t_sector(ent), t_sec(ent), cmd); 11252db270a8SFrederic Weisbecker return trace_seq_printf(s, "[%s]\n", cmd); 11262db270a8SFrederic Weisbecker } 112766de7792SLi Zefan } 11282db270a8SFrederic Weisbecker 11292db270a8SFrederic Weisbecker static int blk_log_with_error(struct trace_seq *s, 11302db270a8SFrederic Weisbecker const struct trace_entry *ent) 11312db270a8SFrederic Weisbecker { 113266de7792SLi Zefan if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { 113366de7792SLi Zefan int ret; 113466de7792SLi Zefan 113566de7792SLi Zefan ret = blk_log_dump_pdu(s, ent); 113666de7792SLi Zefan if (ret) 113766de7792SLi Zefan return trace_seq_printf(s, "[%d]\n", t_error(ent)); 113866de7792SLi Zefan return 0; 113966de7792SLi Zefan } else { 11402db270a8SFrederic Weisbecker if (t_sec(ent)) 114166de7792SLi Zefan return trace_seq_printf(s, "%llu + %u [%d]\n", 114266de7792SLi Zefan t_sector(ent), 11432db270a8SFrederic Weisbecker t_sec(ent), t_error(ent)); 114466de7792SLi Zefan return trace_seq_printf(s, "%llu [%d]\n", 114566de7792SLi Zefan t_sector(ent), t_error(ent)); 114666de7792SLi Zefan } 11472db270a8SFrederic Weisbecker } 11482db270a8SFrederic Weisbecker 11492db270a8SFrederic Weisbecker static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) 11502db270a8SFrederic Weisbecker { 1151a42aaa3bSAlan D. Brunelle struct blk_io_trace_remap r = { .device_from = 0, }; 11522db270a8SFrederic Weisbecker 11532db270a8SFrederic Weisbecker get_pdu_remap(ent, &r); 11542db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", 1155a42aaa3bSAlan D. Brunelle t_sector(ent), t_sec(ent), 1156a42aaa3bSAlan D. Brunelle MAJOR(r.device_from), MINOR(r.device_from), 1157a42aaa3bSAlan D. Brunelle (unsigned long long)r.sector_from); 11582db270a8SFrederic Weisbecker } 11592db270a8SFrederic Weisbecker 11602db270a8SFrederic Weisbecker static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) 11612db270a8SFrederic Weisbecker { 11624ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 11634ca53085SSteven Rostedt 11644ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 11654ca53085SSteven Rostedt 11664ca53085SSteven Rostedt return trace_seq_printf(s, "[%s]\n", cmd); 11672db270a8SFrederic Weisbecker } 11682db270a8SFrederic Weisbecker 11692db270a8SFrederic Weisbecker static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) 11702db270a8SFrederic Weisbecker { 11714ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 11724ca53085SSteven Rostedt 11734ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 11744ca53085SSteven Rostedt 11754ca53085SSteven Rostedt return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); 11762db270a8SFrederic Weisbecker } 11772db270a8SFrederic Weisbecker 11782db270a8SFrederic Weisbecker static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) 11792db270a8SFrederic Weisbecker { 11804ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 11814ca53085SSteven Rostedt 11824ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 11834ca53085SSteven Rostedt 11842db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), 11854ca53085SSteven Rostedt get_pdu_int(ent), cmd); 11862db270a8SFrederic Weisbecker } 11872db270a8SFrederic Weisbecker 118818cea459SLi Zefan static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent) 118918cea459SLi Zefan { 119018cea459SLi Zefan int ret; 119118cea459SLi Zefan const struct blk_io_trace *t = te_blk_io_trace(ent); 119218cea459SLi Zefan 119318cea459SLi Zefan ret = trace_seq_putmem(s, t + 1, t->pdu_len); 119418cea459SLi Zefan if (ret) 119518cea459SLi Zefan return trace_seq_putc(s, '\n'); 119618cea459SLi Zefan return ret; 119718cea459SLi Zefan } 119818cea459SLi Zefan 11992db270a8SFrederic Weisbecker /* 12002db270a8SFrederic Weisbecker * struct tracer operations 12012db270a8SFrederic Weisbecker */ 12022db270a8SFrederic Weisbecker 12032db270a8SFrederic Weisbecker static void blk_tracer_print_header(struct seq_file *m) 12042db270a8SFrederic Weisbecker { 12052db270a8SFrederic Weisbecker if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) 12062db270a8SFrederic Weisbecker return; 12072db270a8SFrederic Weisbecker seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" 12082db270a8SFrederic Weisbecker "# | | | | | |\n"); 12092db270a8SFrederic Weisbecker } 12102db270a8SFrederic Weisbecker 12112db270a8SFrederic Weisbecker static void blk_tracer_start(struct trace_array *tr) 12122db270a8SFrederic Weisbecker { 1213ad5dd549SLi Zefan blk_tracer_enabled = true; 12142db270a8SFrederic Weisbecker } 12152db270a8SFrederic Weisbecker 12162db270a8SFrederic Weisbecker static int blk_tracer_init(struct trace_array *tr) 12172db270a8SFrederic Weisbecker { 12182db270a8SFrederic Weisbecker blk_tr = tr; 12192db270a8SFrederic Weisbecker blk_tracer_start(tr); 12202db270a8SFrederic Weisbecker return 0; 12212db270a8SFrederic Weisbecker } 12222db270a8SFrederic Weisbecker 12232db270a8SFrederic Weisbecker static void blk_tracer_stop(struct trace_array *tr) 12242db270a8SFrederic Weisbecker { 1225ad5dd549SLi Zefan blk_tracer_enabled = false; 12262db270a8SFrederic Weisbecker } 12272db270a8SFrederic Weisbecker 12282db270a8SFrederic Weisbecker static void blk_tracer_reset(struct trace_array *tr) 12292db270a8SFrederic Weisbecker { 12302db270a8SFrederic Weisbecker blk_tracer_stop(tr); 12312db270a8SFrederic Weisbecker } 12322db270a8SFrederic Weisbecker 1233e4955c99SLi Zefan static const struct { 12342db270a8SFrederic Weisbecker const char *act[2]; 12352db270a8SFrederic Weisbecker int (*print)(struct trace_seq *s, const struct trace_entry *ent); 1236e4955c99SLi Zefan } what2act[] = { 12372db270a8SFrederic Weisbecker [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, 12382db270a8SFrederic Weisbecker [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, 12392db270a8SFrederic Weisbecker [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, 12402db270a8SFrederic Weisbecker [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, 12412db270a8SFrederic Weisbecker [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, 12422db270a8SFrederic Weisbecker [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, 12432db270a8SFrederic Weisbecker [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, 12442db270a8SFrederic Weisbecker [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, 12452db270a8SFrederic Weisbecker [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, 12462db270a8SFrederic Weisbecker [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, 12472db270a8SFrederic Weisbecker [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, 12482db270a8SFrederic Weisbecker [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, 12492db270a8SFrederic Weisbecker [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, 12502db270a8SFrederic Weisbecker [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, 12512db270a8SFrederic Weisbecker [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, 12522db270a8SFrederic Weisbecker }; 12532db270a8SFrederic Weisbecker 1254b6a4b0c3SLi Zefan static enum print_line_t print_one_line(struct trace_iterator *iter, 1255b6a4b0c3SLi Zefan bool classic) 12562db270a8SFrederic Weisbecker { 12572db270a8SFrederic Weisbecker struct trace_seq *s = &iter->seq; 1258b6a4b0c3SLi Zefan const struct blk_io_trace *t; 1259b6a4b0c3SLi Zefan u16 what; 12602db270a8SFrederic Weisbecker int ret; 1261b6a4b0c3SLi Zefan bool long_act; 1262b6a4b0c3SLi Zefan blk_log_action_t *log_action; 12632db270a8SFrederic Weisbecker 1264b6a4b0c3SLi Zefan t = te_blk_io_trace(iter->ent); 1265b6a4b0c3SLi Zefan what = t->action & ((1 << BLK_TC_SHIFT) - 1); 1266b6a4b0c3SLi Zefan long_act = !!(trace_flags & TRACE_ITER_VERBOSE); 1267b6a4b0c3SLi Zefan log_action = classic ? &blk_log_action_classic : &blk_log_action; 12682db270a8SFrederic Weisbecker 126918cea459SLi Zefan if (t->action == BLK_TN_MESSAGE) { 127018cea459SLi Zefan ret = log_action(iter, long_act ? "message" : "m"); 127118cea459SLi Zefan if (ret) 127218cea459SLi Zefan ret = blk_log_msg(s, iter->ent); 127318cea459SLi Zefan goto out; 127418cea459SLi Zefan } 127518cea459SLi Zefan 1276eb08f8ebSLi Zefan if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) 1277b78825d6SLi Zefan ret = trace_seq_printf(s, "Unknown action %x\n", what); 12782db270a8SFrederic Weisbecker else { 1279b6a4b0c3SLi Zefan ret = log_action(iter, what2act[what].act[long_act]); 12802db270a8SFrederic Weisbecker if (ret) 12812db270a8SFrederic Weisbecker ret = what2act[what].print(s, iter->ent); 12822db270a8SFrederic Weisbecker } 128318cea459SLi Zefan out: 12842db270a8SFrederic Weisbecker return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; 12852db270a8SFrederic Weisbecker } 12862db270a8SFrederic Weisbecker 1287b6a4b0c3SLi Zefan static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, 1288b6a4b0c3SLi Zefan int flags) 1289b6a4b0c3SLi Zefan { 1290b6a4b0c3SLi Zefan return print_one_line(iter, false); 1291b6a4b0c3SLi Zefan } 1292b6a4b0c3SLi Zefan 12932db270a8SFrederic Weisbecker static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) 12942db270a8SFrederic Weisbecker { 12952db270a8SFrederic Weisbecker struct trace_seq *s = &iter->seq; 12962db270a8SFrederic Weisbecker struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; 12972db270a8SFrederic Weisbecker const int offset = offsetof(struct blk_io_trace, sector); 12982db270a8SFrederic Weisbecker struct blk_io_trace old = { 12992db270a8SFrederic Weisbecker .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, 13006c051ce0SLi Zefan .time = iter->ts, 13012db270a8SFrederic Weisbecker }; 13022db270a8SFrederic Weisbecker 13032db270a8SFrederic Weisbecker if (!trace_seq_putmem(s, &old, offset)) 13042db270a8SFrederic Weisbecker return 0; 13052db270a8SFrederic Weisbecker return trace_seq_putmem(s, &t->sector, 13062db270a8SFrederic Weisbecker sizeof(old) - offset + t->pdu_len); 13072db270a8SFrederic Weisbecker } 13082db270a8SFrederic Weisbecker 13092db270a8SFrederic Weisbecker static enum print_line_t 13102db270a8SFrederic Weisbecker blk_trace_event_print_binary(struct trace_iterator *iter, int flags) 13112db270a8SFrederic Weisbecker { 13122db270a8SFrederic Weisbecker return blk_trace_synthesize_old_trace(iter) ? 13132db270a8SFrederic Weisbecker TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; 13142db270a8SFrederic Weisbecker } 13152db270a8SFrederic Weisbecker 13162db270a8SFrederic Weisbecker static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) 13172db270a8SFrederic Weisbecker { 13182db270a8SFrederic Weisbecker if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) 13192db270a8SFrederic Weisbecker return TRACE_TYPE_UNHANDLED; 13202db270a8SFrederic Weisbecker 1321b6a4b0c3SLi Zefan return print_one_line(iter, true); 13222db270a8SFrederic Weisbecker } 13232db270a8SFrederic Weisbecker 1324f3948f88SLi Zefan static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) 1325f3948f88SLi Zefan { 1326f3948f88SLi Zefan /* don't output context-info for blk_classic output */ 1327f3948f88SLi Zefan if (bit == TRACE_BLK_OPT_CLASSIC) { 1328f3948f88SLi Zefan if (set) 1329f3948f88SLi Zefan trace_flags &= ~TRACE_ITER_CONTEXT_INFO; 1330f3948f88SLi Zefan else 1331f3948f88SLi Zefan trace_flags |= TRACE_ITER_CONTEXT_INFO; 1332f3948f88SLi Zefan } 1333f3948f88SLi Zefan return 0; 1334f3948f88SLi Zefan } 1335f3948f88SLi Zefan 13362db270a8SFrederic Weisbecker static struct tracer blk_tracer __read_mostly = { 13372db270a8SFrederic Weisbecker .name = "blk", 13382db270a8SFrederic Weisbecker .init = blk_tracer_init, 13392db270a8SFrederic Weisbecker .reset = blk_tracer_reset, 13402db270a8SFrederic Weisbecker .start = blk_tracer_start, 13412db270a8SFrederic Weisbecker .stop = blk_tracer_stop, 13422db270a8SFrederic Weisbecker .print_header = blk_tracer_print_header, 13432db270a8SFrederic Weisbecker .print_line = blk_tracer_print_line, 13442db270a8SFrederic Weisbecker .flags = &blk_tracer_flags, 1345f3948f88SLi Zefan .set_flag = blk_tracer_set_flag, 13462db270a8SFrederic Weisbecker }; 13472db270a8SFrederic Weisbecker 13482db270a8SFrederic Weisbecker static struct trace_event trace_blk_event = { 13492db270a8SFrederic Weisbecker .type = TRACE_BLK, 13502db270a8SFrederic Weisbecker .trace = blk_trace_event_print, 13512db270a8SFrederic Weisbecker .binary = blk_trace_event_print_binary, 13522db270a8SFrederic Weisbecker }; 13532db270a8SFrederic Weisbecker 13542db270a8SFrederic Weisbecker static int __init init_blk_tracer(void) 13552db270a8SFrederic Weisbecker { 13562db270a8SFrederic Weisbecker if (!register_ftrace_event(&trace_blk_event)) { 13572db270a8SFrederic Weisbecker pr_warning("Warning: could not register block events\n"); 13582db270a8SFrederic Weisbecker return 1; 13592db270a8SFrederic Weisbecker } 13602db270a8SFrederic Weisbecker 13612db270a8SFrederic Weisbecker if (register_tracer(&blk_tracer) != 0) { 13622db270a8SFrederic Weisbecker pr_warning("Warning: could not register the block tracer\n"); 13632db270a8SFrederic Weisbecker unregister_ftrace_event(&trace_blk_event); 13642db270a8SFrederic Weisbecker return 1; 13652db270a8SFrederic Weisbecker } 13662db270a8SFrederic Weisbecker 13672db270a8SFrederic Weisbecker return 0; 13682db270a8SFrederic Weisbecker } 13692db270a8SFrederic Weisbecker 13702db270a8SFrederic Weisbecker device_initcall(init_blk_tracer); 13712db270a8SFrederic Weisbecker 13722db270a8SFrederic Weisbecker static int blk_trace_remove_queue(struct request_queue *q) 13732db270a8SFrederic Weisbecker { 13742db270a8SFrederic Weisbecker struct blk_trace *bt; 13752db270a8SFrederic Weisbecker 13762db270a8SFrederic Weisbecker bt = xchg(&q->blk_trace, NULL); 13772db270a8SFrederic Weisbecker if (bt == NULL) 13782db270a8SFrederic Weisbecker return -EINVAL; 13792db270a8SFrederic Weisbecker 138017ba97e3SLi Zefan if (atomic_dec_and_test(&blk_probes_ref)) 138117ba97e3SLi Zefan blk_unregister_tracepoints(); 138217ba97e3SLi Zefan 1383ad5dd549SLi Zefan blk_trace_free(bt); 13842db270a8SFrederic Weisbecker return 0; 13852db270a8SFrederic Weisbecker } 13862db270a8SFrederic Weisbecker 13872db270a8SFrederic Weisbecker /* 13882db270a8SFrederic Weisbecker * Setup everything required to start tracing 13892db270a8SFrederic Weisbecker */ 13909908c309SLi Zefan static int blk_trace_setup_queue(struct request_queue *q, 13919908c309SLi Zefan struct block_device *bdev) 13922db270a8SFrederic Weisbecker { 13932db270a8SFrederic Weisbecker struct blk_trace *old_bt, *bt = NULL; 139418cea459SLi Zefan int ret = -ENOMEM; 13952db270a8SFrederic Weisbecker 13962db270a8SFrederic Weisbecker bt = kzalloc(sizeof(*bt), GFP_KERNEL); 13972db270a8SFrederic Weisbecker if (!bt) 139815152e44SLi Zefan return -ENOMEM; 13992db270a8SFrederic Weisbecker 140018cea459SLi Zefan bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); 140118cea459SLi Zefan if (!bt->msg_data) 140218cea459SLi Zefan goto free_bt; 140318cea459SLi Zefan 14049908c309SLi Zefan bt->dev = bdev->bd_dev; 14052db270a8SFrederic Weisbecker bt->act_mask = (u16)-1; 14069908c309SLi Zefan 14079908c309SLi Zefan blk_trace_setup_lba(bt, bdev); 14082db270a8SFrederic Weisbecker 14092db270a8SFrederic Weisbecker old_bt = xchg(&q->blk_trace, bt); 14102db270a8SFrederic Weisbecker if (old_bt != NULL) { 14112db270a8SFrederic Weisbecker (void)xchg(&q->blk_trace, old_bt); 141218cea459SLi Zefan ret = -EBUSY; 141318cea459SLi Zefan goto free_bt; 14142db270a8SFrederic Weisbecker } 141515152e44SLi Zefan 141617ba97e3SLi Zefan if (atomic_inc_return(&blk_probes_ref) == 1) 141717ba97e3SLi Zefan blk_register_tracepoints(); 14182db270a8SFrederic Weisbecker return 0; 141918cea459SLi Zefan 142018cea459SLi Zefan free_bt: 142118cea459SLi Zefan blk_trace_free(bt); 142218cea459SLi Zefan return ret; 14232db270a8SFrederic Weisbecker } 14242db270a8SFrederic Weisbecker 14252db270a8SFrederic Weisbecker /* 14262db270a8SFrederic Weisbecker * sysfs interface to enable and configure tracing 14272db270a8SFrederic Weisbecker */ 14282db270a8SFrederic Weisbecker 14292db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_show(struct device *dev, 14302db270a8SFrederic Weisbecker struct device_attribute *attr, 14312db270a8SFrederic Weisbecker char *buf); 14322db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_store(struct device *dev, 14332db270a8SFrederic Weisbecker struct device_attribute *attr, 14342db270a8SFrederic Weisbecker const char *buf, size_t count); 14352db270a8SFrederic Weisbecker #define BLK_TRACE_DEVICE_ATTR(_name) \ 14362db270a8SFrederic Weisbecker DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ 14372db270a8SFrederic Weisbecker sysfs_blk_trace_attr_show, \ 14382db270a8SFrederic Weisbecker sysfs_blk_trace_attr_store) 14392db270a8SFrederic Weisbecker 1440cd649b8bSLi Zefan static BLK_TRACE_DEVICE_ATTR(enable); 14412db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(act_mask); 14422db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(pid); 14432db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(start_lba); 14442db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(end_lba); 14452db270a8SFrederic Weisbecker 14462db270a8SFrederic Weisbecker static struct attribute *blk_trace_attrs[] = { 14472db270a8SFrederic Weisbecker &dev_attr_enable.attr, 14482db270a8SFrederic Weisbecker &dev_attr_act_mask.attr, 14492db270a8SFrederic Weisbecker &dev_attr_pid.attr, 14502db270a8SFrederic Weisbecker &dev_attr_start_lba.attr, 14512db270a8SFrederic Weisbecker &dev_attr_end_lba.attr, 14522db270a8SFrederic Weisbecker NULL 14532db270a8SFrederic Weisbecker }; 14542db270a8SFrederic Weisbecker 14552db270a8SFrederic Weisbecker struct attribute_group blk_trace_attr_group = { 14562db270a8SFrederic Weisbecker .name = "trace", 14572db270a8SFrederic Weisbecker .attrs = blk_trace_attrs, 14582db270a8SFrederic Weisbecker }; 14592db270a8SFrederic Weisbecker 146009341997SLi Zefan static const struct { 146109341997SLi Zefan int mask; 146209341997SLi Zefan const char *str; 146309341997SLi Zefan } mask_maps[] = { 146409341997SLi Zefan { BLK_TC_READ, "read" }, 146509341997SLi Zefan { BLK_TC_WRITE, "write" }, 146609341997SLi Zefan { BLK_TC_BARRIER, "barrier" }, 146709341997SLi Zefan { BLK_TC_SYNC, "sync" }, 146809341997SLi Zefan { BLK_TC_QUEUE, "queue" }, 146909341997SLi Zefan { BLK_TC_REQUEUE, "requeue" }, 147009341997SLi Zefan { BLK_TC_ISSUE, "issue" }, 147109341997SLi Zefan { BLK_TC_COMPLETE, "complete" }, 147209341997SLi Zefan { BLK_TC_FS, "fs" }, 147309341997SLi Zefan { BLK_TC_PC, "pc" }, 147409341997SLi Zefan { BLK_TC_AHEAD, "ahead" }, 147509341997SLi Zefan { BLK_TC_META, "meta" }, 147609341997SLi Zefan { BLK_TC_DISCARD, "discard" }, 147709341997SLi Zefan { BLK_TC_DRV_DATA, "drv_data" }, 147809341997SLi Zefan }; 147909341997SLi Zefan 148009341997SLi Zefan static int blk_trace_str2mask(const char *str) 14812db270a8SFrederic Weisbecker { 148209341997SLi Zefan int i; 14832db270a8SFrederic Weisbecker int mask = 0; 14849eb85125SLi Zefan char *buf, *s, *token; 14852db270a8SFrederic Weisbecker 14869eb85125SLi Zefan buf = kstrdup(str, GFP_KERNEL); 14879eb85125SLi Zefan if (buf == NULL) 14882db270a8SFrederic Weisbecker return -ENOMEM; 14899eb85125SLi Zefan s = strstrip(buf); 14902db270a8SFrederic Weisbecker 14912db270a8SFrederic Weisbecker while (1) { 149209341997SLi Zefan token = strsep(&s, ","); 149309341997SLi Zefan if (token == NULL) 14942db270a8SFrederic Weisbecker break; 14952db270a8SFrederic Weisbecker 149609341997SLi Zefan if (*token == '\0') 149709341997SLi Zefan continue; 149809341997SLi Zefan 149909341997SLi Zefan for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { 150009341997SLi Zefan if (strcasecmp(token, mask_maps[i].str) == 0) { 150109341997SLi Zefan mask |= mask_maps[i].mask; 150209341997SLi Zefan break; 15032db270a8SFrederic Weisbecker } 150409341997SLi Zefan } 150509341997SLi Zefan if (i == ARRAY_SIZE(mask_maps)) { 150609341997SLi Zefan mask = -EINVAL; 150709341997SLi Zefan break; 150809341997SLi Zefan } 150909341997SLi Zefan } 15109eb85125SLi Zefan kfree(buf); 15112db270a8SFrederic Weisbecker 15122db270a8SFrederic Weisbecker return mask; 15132db270a8SFrederic Weisbecker } 15142db270a8SFrederic Weisbecker 151509341997SLi Zefan static ssize_t blk_trace_mask2str(char *buf, int mask) 151609341997SLi Zefan { 151709341997SLi Zefan int i; 151809341997SLi Zefan char *p = buf; 151909341997SLi Zefan 152009341997SLi Zefan for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { 152109341997SLi Zefan if (mask & mask_maps[i].mask) { 152209341997SLi Zefan p += sprintf(p, "%s%s", 152309341997SLi Zefan (p == buf) ? "" : ",", mask_maps[i].str); 152409341997SLi Zefan } 152509341997SLi Zefan } 152609341997SLi Zefan *p++ = '\n'; 152709341997SLi Zefan 152809341997SLi Zefan return p - buf; 152909341997SLi Zefan } 153009341997SLi Zefan 1531b125130bSLi Zefan static struct request_queue *blk_trace_get_queue(struct block_device *bdev) 1532b125130bSLi Zefan { 1533b125130bSLi Zefan if (bdev->bd_disk == NULL) 1534b125130bSLi Zefan return NULL; 1535b125130bSLi Zefan 1536b125130bSLi Zefan return bdev_get_queue(bdev); 1537b125130bSLi Zefan } 1538b125130bSLi Zefan 15392db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_show(struct device *dev, 15402db270a8SFrederic Weisbecker struct device_attribute *attr, 15412db270a8SFrederic Weisbecker char *buf) 15422db270a8SFrederic Weisbecker { 15432db270a8SFrederic Weisbecker struct hd_struct *p = dev_to_part(dev); 15442db270a8SFrederic Weisbecker struct request_queue *q; 15452db270a8SFrederic Weisbecker struct block_device *bdev; 15462db270a8SFrederic Weisbecker ssize_t ret = -ENXIO; 15472db270a8SFrederic Weisbecker 15482db270a8SFrederic Weisbecker lock_kernel(); 15492db270a8SFrederic Weisbecker bdev = bdget(part_devt(p)); 15502db270a8SFrederic Weisbecker if (bdev == NULL) 15512db270a8SFrederic Weisbecker goto out_unlock_kernel; 15522db270a8SFrederic Weisbecker 1553b125130bSLi Zefan q = blk_trace_get_queue(bdev); 15542db270a8SFrederic Weisbecker if (q == NULL) 15552db270a8SFrederic Weisbecker goto out_bdput; 1556b125130bSLi Zefan 15572db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 1558cd649b8bSLi Zefan 1559cd649b8bSLi Zefan if (attr == &dev_attr_enable) { 1560cd649b8bSLi Zefan ret = sprintf(buf, "%u\n", !!q->blk_trace); 1561cd649b8bSLi Zefan goto out_unlock_bdev; 1562cd649b8bSLi Zefan } 1563cd649b8bSLi Zefan 15642db270a8SFrederic Weisbecker if (q->blk_trace == NULL) 15652db270a8SFrederic Weisbecker ret = sprintf(buf, "disabled\n"); 15662db270a8SFrederic Weisbecker else if (attr == &dev_attr_act_mask) 156709341997SLi Zefan ret = blk_trace_mask2str(buf, q->blk_trace->act_mask); 15682db270a8SFrederic Weisbecker else if (attr == &dev_attr_pid) 15692db270a8SFrederic Weisbecker ret = sprintf(buf, "%u\n", q->blk_trace->pid); 15702db270a8SFrederic Weisbecker else if (attr == &dev_attr_start_lba) 15712db270a8SFrederic Weisbecker ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); 15722db270a8SFrederic Weisbecker else if (attr == &dev_attr_end_lba) 15732db270a8SFrederic Weisbecker ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); 1574cd649b8bSLi Zefan 1575cd649b8bSLi Zefan out_unlock_bdev: 15762db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 15772db270a8SFrederic Weisbecker out_bdput: 15782db270a8SFrederic Weisbecker bdput(bdev); 15792db270a8SFrederic Weisbecker out_unlock_kernel: 15802db270a8SFrederic Weisbecker unlock_kernel(); 15812db270a8SFrederic Weisbecker return ret; 15822db270a8SFrederic Weisbecker } 15832db270a8SFrederic Weisbecker 15842db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_store(struct device *dev, 15852db270a8SFrederic Weisbecker struct device_attribute *attr, 15862db270a8SFrederic Weisbecker const char *buf, size_t count) 15872db270a8SFrederic Weisbecker { 15882db270a8SFrederic Weisbecker struct block_device *bdev; 15892db270a8SFrederic Weisbecker struct request_queue *q; 15902db270a8SFrederic Weisbecker struct hd_struct *p; 15912db270a8SFrederic Weisbecker u64 value; 159209341997SLi Zefan ssize_t ret = -EINVAL; 15932db270a8SFrederic Weisbecker 15942db270a8SFrederic Weisbecker if (count == 0) 15952db270a8SFrederic Weisbecker goto out; 15962db270a8SFrederic Weisbecker 15972db270a8SFrederic Weisbecker if (attr == &dev_attr_act_mask) { 15982db270a8SFrederic Weisbecker if (sscanf(buf, "%llx", &value) != 1) { 15992db270a8SFrederic Weisbecker /* Assume it is a list of trace category names */ 160009341997SLi Zefan ret = blk_trace_str2mask(buf); 160109341997SLi Zefan if (ret < 0) 16022db270a8SFrederic Weisbecker goto out; 160309341997SLi Zefan value = ret; 16042db270a8SFrederic Weisbecker } 16052db270a8SFrederic Weisbecker } else if (sscanf(buf, "%llu", &value) != 1) 16062db270a8SFrederic Weisbecker goto out; 16072db270a8SFrederic Weisbecker 160809341997SLi Zefan ret = -ENXIO; 160909341997SLi Zefan 16102db270a8SFrederic Weisbecker lock_kernel(); 16112db270a8SFrederic Weisbecker p = dev_to_part(dev); 16122db270a8SFrederic Weisbecker bdev = bdget(part_devt(p)); 16132db270a8SFrederic Weisbecker if (bdev == NULL) 16142db270a8SFrederic Weisbecker goto out_unlock_kernel; 16152db270a8SFrederic Weisbecker 1616b125130bSLi Zefan q = blk_trace_get_queue(bdev); 16172db270a8SFrederic Weisbecker if (q == NULL) 16182db270a8SFrederic Weisbecker goto out_bdput; 16192db270a8SFrederic Weisbecker 16202db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 1621cd649b8bSLi Zefan 1622cd649b8bSLi Zefan if (attr == &dev_attr_enable) { 1623cd649b8bSLi Zefan if (value) 16249908c309SLi Zefan ret = blk_trace_setup_queue(q, bdev); 1625cd649b8bSLi Zefan else 1626cd649b8bSLi Zefan ret = blk_trace_remove_queue(q); 1627cd649b8bSLi Zefan goto out_unlock_bdev; 1628cd649b8bSLi Zefan } 1629cd649b8bSLi Zefan 16302db270a8SFrederic Weisbecker ret = 0; 16312db270a8SFrederic Weisbecker if (q->blk_trace == NULL) 16329908c309SLi Zefan ret = blk_trace_setup_queue(q, bdev); 16332db270a8SFrederic Weisbecker 16342db270a8SFrederic Weisbecker if (ret == 0) { 16352db270a8SFrederic Weisbecker if (attr == &dev_attr_act_mask) 16362db270a8SFrederic Weisbecker q->blk_trace->act_mask = value; 16372db270a8SFrederic Weisbecker else if (attr == &dev_attr_pid) 16382db270a8SFrederic Weisbecker q->blk_trace->pid = value; 16392db270a8SFrederic Weisbecker else if (attr == &dev_attr_start_lba) 16402db270a8SFrederic Weisbecker q->blk_trace->start_lba = value; 16412db270a8SFrederic Weisbecker else if (attr == &dev_attr_end_lba) 16422db270a8SFrederic Weisbecker q->blk_trace->end_lba = value; 16432db270a8SFrederic Weisbecker } 1644cd649b8bSLi Zefan 1645cd649b8bSLi Zefan out_unlock_bdev: 16462db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 16472db270a8SFrederic Weisbecker out_bdput: 16482db270a8SFrederic Weisbecker bdput(bdev); 16492db270a8SFrederic Weisbecker out_unlock_kernel: 16502db270a8SFrederic Weisbecker unlock_kernel(); 16512db270a8SFrederic Weisbecker out: 1652cd649b8bSLi Zefan return ret ? ret : count; 16532db270a8SFrederic Weisbecker } 1654cd649b8bSLi Zefan 16551d54ad6dSLi Zefan int blk_trace_init_sysfs(struct device *dev) 16561d54ad6dSLi Zefan { 16571d54ad6dSLi Zefan return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); 16581d54ad6dSLi Zefan } 16591d54ad6dSLi Zefan 1660