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> 25405f5571SAlexey Dobriyan #include <linux/smp_lock.h> 262db270a8SFrederic Weisbecker #include <linux/time.h> 272db270a8SFrederic Weisbecker #include <linux/uaccess.h> 2855782138SLi Zefan 2955782138SLi Zefan #include <trace/events/block.h> 3055782138SLi Zefan 312db270a8SFrederic Weisbecker #include "trace_output.h" 322db270a8SFrederic Weisbecker 3355782138SLi Zefan #ifdef CONFIG_BLK_DEV_IO_TRACE 3455782138SLi Zefan 352db270a8SFrederic Weisbecker static unsigned int blktrace_seq __read_mostly = 1; 362db270a8SFrederic Weisbecker 372db270a8SFrederic Weisbecker static struct trace_array *blk_tr; 385006ea73SLi Zefan static bool blk_tracer_enabled __read_mostly; 392db270a8SFrederic Weisbecker 402db270a8SFrederic Weisbecker /* Select an alternative, minimalistic output than the original one */ 412db270a8SFrederic Weisbecker #define TRACE_BLK_OPT_CLASSIC 0x1 422db270a8SFrederic Weisbecker 432db270a8SFrederic Weisbecker static struct tracer_opt blk_tracer_opts[] = { 442db270a8SFrederic Weisbecker /* Default disable the minimalistic output */ 452db270a8SFrederic Weisbecker { TRACER_OPT(blk_classic, TRACE_BLK_OPT_CLASSIC) }, 462db270a8SFrederic Weisbecker { } 472db270a8SFrederic Weisbecker }; 482db270a8SFrederic Weisbecker 492db270a8SFrederic Weisbecker static struct tracer_flags blk_tracer_flags = { 502db270a8SFrederic Weisbecker .val = 0, 512db270a8SFrederic Weisbecker .opts = blk_tracer_opts, 522db270a8SFrederic Weisbecker }; 532db270a8SFrederic Weisbecker 542db270a8SFrederic Weisbecker /* Global reference count of probes */ 552db270a8SFrederic Weisbecker static atomic_t blk_probes_ref = ATOMIC_INIT(0); 562db270a8SFrederic Weisbecker 573c289ba7SLi Zefan static void blk_register_tracepoints(void); 582db270a8SFrederic Weisbecker static void blk_unregister_tracepoints(void); 592db270a8SFrederic Weisbecker 602db270a8SFrederic Weisbecker /* 612db270a8SFrederic Weisbecker * Send out a notify message. 622db270a8SFrederic Weisbecker */ 632db270a8SFrederic Weisbecker static void trace_note(struct blk_trace *bt, pid_t pid, int action, 642db270a8SFrederic Weisbecker const void *data, size_t len) 652db270a8SFrederic Weisbecker { 662db270a8SFrederic Weisbecker struct blk_io_trace *t; 6718cea459SLi Zefan struct ring_buffer_event *event = NULL; 6818cea459SLi Zefan int pc = 0; 6918cea459SLi Zefan int cpu = smp_processor_id(); 7018cea459SLi Zefan bool blk_tracer = blk_tracer_enabled; 7118cea459SLi Zefan 7218cea459SLi Zefan if (blk_tracer) { 7318cea459SLi Zefan pc = preempt_count(); 7418cea459SLi Zefan event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK, 7518cea459SLi Zefan sizeof(*t) + len, 7618cea459SLi Zefan 0, pc); 7718cea459SLi Zefan if (!event) 7818cea459SLi Zefan return; 7918cea459SLi Zefan t = ring_buffer_event_data(event); 8018cea459SLi Zefan goto record_it; 8118cea459SLi Zefan } 822db270a8SFrederic Weisbecker 832db270a8SFrederic Weisbecker if (!bt->rchan) 842db270a8SFrederic Weisbecker return; 852db270a8SFrederic Weisbecker 862db270a8SFrederic Weisbecker t = relay_reserve(bt->rchan, sizeof(*t) + len); 872db270a8SFrederic Weisbecker if (t) { 882db270a8SFrederic Weisbecker t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; 892db270a8SFrederic Weisbecker t->time = ktime_to_ns(ktime_get()); 9018cea459SLi Zefan record_it: 912db270a8SFrederic Weisbecker t->device = bt->dev; 922db270a8SFrederic Weisbecker t->action = action; 932db270a8SFrederic Weisbecker t->pid = pid; 942db270a8SFrederic Weisbecker t->cpu = cpu; 952db270a8SFrederic Weisbecker t->pdu_len = len; 962db270a8SFrederic Weisbecker memcpy((void *) t + sizeof(*t), data, len); 9718cea459SLi Zefan 9818cea459SLi Zefan if (blk_tracer) 9918cea459SLi Zefan trace_buffer_unlock_commit(blk_tr, event, 0, pc); 1002db270a8SFrederic Weisbecker } 1012db270a8SFrederic Weisbecker } 1022db270a8SFrederic Weisbecker 1032db270a8SFrederic Weisbecker /* 1042db270a8SFrederic Weisbecker * Send out a notify for this process, if we haven't done so since a trace 1052db270a8SFrederic Weisbecker * started 1062db270a8SFrederic Weisbecker */ 1072db270a8SFrederic Weisbecker static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) 1082db270a8SFrederic Weisbecker { 1092db270a8SFrederic Weisbecker tsk->btrace_seq = blktrace_seq; 1102db270a8SFrederic Weisbecker trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm)); 1112db270a8SFrederic Weisbecker } 1122db270a8SFrederic Weisbecker 1132db270a8SFrederic Weisbecker static void trace_note_time(struct blk_trace *bt) 1142db270a8SFrederic Weisbecker { 1152db270a8SFrederic Weisbecker struct timespec now; 1162db270a8SFrederic Weisbecker unsigned long flags; 1172db270a8SFrederic Weisbecker u32 words[2]; 1182db270a8SFrederic Weisbecker 1192db270a8SFrederic Weisbecker getnstimeofday(&now); 1202db270a8SFrederic Weisbecker words[0] = now.tv_sec; 1212db270a8SFrederic Weisbecker words[1] = now.tv_nsec; 1222db270a8SFrederic Weisbecker 1232db270a8SFrederic Weisbecker local_irq_save(flags); 1242db270a8SFrederic Weisbecker trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words)); 1252db270a8SFrederic Weisbecker local_irq_restore(flags); 1262db270a8SFrederic Weisbecker } 1272db270a8SFrederic Weisbecker 1282db270a8SFrederic Weisbecker void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) 1292db270a8SFrederic Weisbecker { 1302db270a8SFrederic Weisbecker int n; 1312db270a8SFrederic Weisbecker va_list args; 1322db270a8SFrederic Weisbecker unsigned long flags; 1332db270a8SFrederic Weisbecker char *buf; 1342db270a8SFrederic Weisbecker 13518cea459SLi Zefan if (unlikely(bt->trace_state != Blktrace_running && 13618cea459SLi Zefan !blk_tracer_enabled)) 1372db270a8SFrederic Weisbecker return; 1382db270a8SFrederic Weisbecker 1392db270a8SFrederic Weisbecker local_irq_save(flags); 1402db270a8SFrederic Weisbecker buf = per_cpu_ptr(bt->msg_data, smp_processor_id()); 1412db270a8SFrederic Weisbecker va_start(args, fmt); 1422db270a8SFrederic Weisbecker n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); 1432db270a8SFrederic Weisbecker va_end(args); 1442db270a8SFrederic Weisbecker 1452db270a8SFrederic Weisbecker trace_note(bt, 0, BLK_TN_MESSAGE, buf, n); 1462db270a8SFrederic Weisbecker local_irq_restore(flags); 1472db270a8SFrederic Weisbecker } 1482db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(__trace_note_message); 1492db270a8SFrederic Weisbecker 1502db270a8SFrederic Weisbecker static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, 1512db270a8SFrederic Weisbecker pid_t pid) 1522db270a8SFrederic Weisbecker { 1532db270a8SFrederic Weisbecker if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) 1542db270a8SFrederic Weisbecker return 1; 155d0deef5bSShawn Du if (sector && (sector < bt->start_lba || sector > bt->end_lba)) 1562db270a8SFrederic Weisbecker return 1; 1572db270a8SFrederic Weisbecker if (bt->pid && pid != bt->pid) 1582db270a8SFrederic Weisbecker return 1; 1592db270a8SFrederic Weisbecker 1602db270a8SFrederic Weisbecker return 0; 1612db270a8SFrederic Weisbecker } 1622db270a8SFrederic Weisbecker 1632db270a8SFrederic Weisbecker /* 1642db270a8SFrederic Weisbecker * Data direction bit lookup 1652db270a8SFrederic Weisbecker */ 166e4955c99SLi Zefan static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ), 1672db270a8SFrederic Weisbecker BLK_TC_ACT(BLK_TC_WRITE) }; 1682db270a8SFrederic Weisbecker 1692db270a8SFrederic Weisbecker /* The ilog2() calls fall out because they're constant */ 1702db270a8SFrederic Weisbecker #define MASK_TC_BIT(rw, __name) ((rw & (1 << BIO_RW_ ## __name)) << \ 1712db270a8SFrederic Weisbecker (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - BIO_RW_ ## __name)) 1722db270a8SFrederic Weisbecker 1732db270a8SFrederic Weisbecker /* 1742db270a8SFrederic Weisbecker * The worker for the various blk_add_trace*() types. Fills out a 1752db270a8SFrederic Weisbecker * blk_io_trace structure and places it in a per-cpu subbuffer. 1762db270a8SFrederic Weisbecker */ 1772db270a8SFrederic Weisbecker static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, 1782db270a8SFrederic Weisbecker int rw, u32 what, int error, int pdu_len, void *pdu_data) 1792db270a8SFrederic Weisbecker { 1802db270a8SFrederic Weisbecker struct task_struct *tsk = current; 1812db270a8SFrederic Weisbecker struct ring_buffer_event *event = NULL; 1822db270a8SFrederic Weisbecker struct blk_io_trace *t; 1832db270a8SFrederic Weisbecker unsigned long flags = 0; 1842db270a8SFrederic Weisbecker unsigned long *sequence; 1852db270a8SFrederic Weisbecker pid_t pid; 1862db270a8SFrederic Weisbecker int cpu, pc = 0; 18718cea459SLi Zefan bool blk_tracer = blk_tracer_enabled; 1882db270a8SFrederic Weisbecker 18918cea459SLi Zefan if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer)) 1902db270a8SFrederic Weisbecker return; 1912db270a8SFrederic Weisbecker 1922db270a8SFrederic Weisbecker what |= ddir_act[rw & WRITE]; 1932db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, BARRIER); 19472c26c9aSIngo Molnar what |= MASK_TC_BIT(rw, SYNCIO); 1952db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, AHEAD); 1962db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, META); 1972db270a8SFrederic Weisbecker what |= MASK_TC_BIT(rw, DISCARD); 1982db270a8SFrederic Weisbecker 1992db270a8SFrederic Weisbecker pid = tsk->pid; 200d0deef5bSShawn Du if (act_log_check(bt, what, sector, pid)) 2012db270a8SFrederic Weisbecker return; 2022db270a8SFrederic Weisbecker cpu = raw_smp_processor_id(); 2032db270a8SFrederic Weisbecker 20418cea459SLi Zefan if (blk_tracer) { 2052db270a8SFrederic Weisbecker tracing_record_cmdline(current); 2062db270a8SFrederic Weisbecker 2072db270a8SFrederic Weisbecker pc = preempt_count(); 2082db270a8SFrederic Weisbecker event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK, 2092db270a8SFrederic Weisbecker sizeof(*t) + pdu_len, 2102db270a8SFrederic Weisbecker 0, pc); 2112db270a8SFrederic Weisbecker if (!event) 2122db270a8SFrederic Weisbecker return; 2132db270a8SFrederic Weisbecker t = ring_buffer_event_data(event); 2142db270a8SFrederic Weisbecker goto record_it; 2152db270a8SFrederic Weisbecker } 2162db270a8SFrederic Weisbecker 2172db270a8SFrederic Weisbecker /* 2182db270a8SFrederic Weisbecker * A word about the locking here - we disable interrupts to reserve 2192db270a8SFrederic Weisbecker * some space in the relay per-cpu buffer, to prevent an irq 2202db270a8SFrederic Weisbecker * from coming in and stepping on our toes. 2212db270a8SFrederic Weisbecker */ 2222db270a8SFrederic Weisbecker local_irq_save(flags); 2232db270a8SFrederic Weisbecker 2242db270a8SFrederic Weisbecker if (unlikely(tsk->btrace_seq != blktrace_seq)) 2252db270a8SFrederic Weisbecker trace_note_tsk(bt, tsk); 2262db270a8SFrederic Weisbecker 2272db270a8SFrederic Weisbecker t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); 2282db270a8SFrederic Weisbecker if (t) { 2292db270a8SFrederic Weisbecker sequence = per_cpu_ptr(bt->sequence, cpu); 2302db270a8SFrederic Weisbecker 2312db270a8SFrederic Weisbecker t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; 2322db270a8SFrederic Weisbecker t->sequence = ++(*sequence); 2332db270a8SFrederic Weisbecker t->time = ktime_to_ns(ktime_get()); 2342db270a8SFrederic Weisbecker record_it: 2352db270a8SFrederic Weisbecker /* 2362db270a8SFrederic Weisbecker * These two are not needed in ftrace as they are in the 2372db270a8SFrederic Weisbecker * generic trace_entry, filled by tracing_generic_entry_update, 2382db270a8SFrederic Weisbecker * but for the trace_event->bin() synthesizer benefit we do it 2392db270a8SFrederic Weisbecker * here too. 2402db270a8SFrederic Weisbecker */ 2412db270a8SFrederic Weisbecker t->cpu = cpu; 2422db270a8SFrederic Weisbecker t->pid = pid; 2432db270a8SFrederic Weisbecker 2442db270a8SFrederic Weisbecker t->sector = sector; 2452db270a8SFrederic Weisbecker t->bytes = bytes; 2462db270a8SFrederic Weisbecker t->action = what; 2472db270a8SFrederic Weisbecker t->device = bt->dev; 2482db270a8SFrederic Weisbecker t->error = error; 2492db270a8SFrederic Weisbecker t->pdu_len = pdu_len; 2502db270a8SFrederic Weisbecker 2512db270a8SFrederic Weisbecker if (pdu_len) 2522db270a8SFrederic Weisbecker memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); 2532db270a8SFrederic Weisbecker 25418cea459SLi Zefan if (blk_tracer) { 2552db270a8SFrederic Weisbecker trace_buffer_unlock_commit(blk_tr, event, 0, pc); 2562db270a8SFrederic Weisbecker return; 2572db270a8SFrederic Weisbecker } 2582db270a8SFrederic Weisbecker } 2592db270a8SFrederic Weisbecker 2602db270a8SFrederic Weisbecker local_irq_restore(flags); 2612db270a8SFrederic Weisbecker } 2622db270a8SFrederic Weisbecker 2632db270a8SFrederic Weisbecker static struct dentry *blk_tree_root; 2642db270a8SFrederic Weisbecker static DEFINE_MUTEX(blk_tree_mutex); 2652db270a8SFrederic Weisbecker 266ad5dd549SLi Zefan static void blk_trace_free(struct blk_trace *bt) 2672db270a8SFrederic Weisbecker { 2682db270a8SFrederic Weisbecker debugfs_remove(bt->msg_file); 2692db270a8SFrederic Weisbecker debugfs_remove(bt->dropped_file); 270fd51d251SStefan Raspl debugfs_remove(bt->dir); 2712db270a8SFrederic Weisbecker relay_close(bt->rchan); 2722db270a8SFrederic Weisbecker free_percpu(bt->sequence); 2732db270a8SFrederic Weisbecker free_percpu(bt->msg_data); 2742db270a8SFrederic Weisbecker kfree(bt); 275ad5dd549SLi Zefan } 276ad5dd549SLi Zefan 277ad5dd549SLi Zefan static void blk_trace_cleanup(struct blk_trace *bt) 278ad5dd549SLi Zefan { 279ad5dd549SLi Zefan blk_trace_free(bt); 2802db270a8SFrederic Weisbecker if (atomic_dec_and_test(&blk_probes_ref)) 2812db270a8SFrederic Weisbecker blk_unregister_tracepoints(); 2822db270a8SFrederic Weisbecker } 2832db270a8SFrederic Weisbecker 2842db270a8SFrederic Weisbecker int blk_trace_remove(struct request_queue *q) 2852db270a8SFrederic Weisbecker { 2862db270a8SFrederic Weisbecker struct blk_trace *bt; 2872db270a8SFrederic Weisbecker 2882db270a8SFrederic Weisbecker bt = xchg(&q->blk_trace, NULL); 2892db270a8SFrederic Weisbecker if (!bt) 2902db270a8SFrederic Weisbecker return -EINVAL; 2912db270a8SFrederic Weisbecker 29255547204SLi Zefan if (bt->trace_state != Blktrace_running) 2932db270a8SFrederic Weisbecker blk_trace_cleanup(bt); 2942db270a8SFrederic Weisbecker 2952db270a8SFrederic Weisbecker return 0; 2962db270a8SFrederic Weisbecker } 2972db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_remove); 2982db270a8SFrederic Weisbecker 2992db270a8SFrederic Weisbecker static int blk_dropped_open(struct inode *inode, struct file *filp) 3002db270a8SFrederic Weisbecker { 3012db270a8SFrederic Weisbecker filp->private_data = inode->i_private; 3022db270a8SFrederic Weisbecker 3032db270a8SFrederic Weisbecker return 0; 3042db270a8SFrederic Weisbecker } 3052db270a8SFrederic Weisbecker 3062db270a8SFrederic Weisbecker static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, 3072db270a8SFrederic Weisbecker size_t count, loff_t *ppos) 3082db270a8SFrederic Weisbecker { 3092db270a8SFrederic Weisbecker struct blk_trace *bt = filp->private_data; 3102db270a8SFrederic Weisbecker char buf[16]; 3112db270a8SFrederic Weisbecker 3122db270a8SFrederic Weisbecker snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); 3132db270a8SFrederic Weisbecker 3142db270a8SFrederic Weisbecker return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); 3152db270a8SFrederic Weisbecker } 3162db270a8SFrederic Weisbecker 3172db270a8SFrederic Weisbecker static const struct file_operations blk_dropped_fops = { 3182db270a8SFrederic Weisbecker .owner = THIS_MODULE, 3192db270a8SFrederic Weisbecker .open = blk_dropped_open, 3202db270a8SFrederic Weisbecker .read = blk_dropped_read, 3212db270a8SFrederic Weisbecker }; 3222db270a8SFrederic Weisbecker 3232db270a8SFrederic Weisbecker static int blk_msg_open(struct inode *inode, struct file *filp) 3242db270a8SFrederic Weisbecker { 3252db270a8SFrederic Weisbecker filp->private_data = inode->i_private; 3262db270a8SFrederic Weisbecker 3272db270a8SFrederic Weisbecker return 0; 3282db270a8SFrederic Weisbecker } 3292db270a8SFrederic Weisbecker 3302db270a8SFrederic Weisbecker static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, 3312db270a8SFrederic Weisbecker size_t count, loff_t *ppos) 3322db270a8SFrederic Weisbecker { 3332db270a8SFrederic Weisbecker char *msg; 3342db270a8SFrederic Weisbecker struct blk_trace *bt; 3352db270a8SFrederic Weisbecker 3367635b03aSLi Zefan if (count >= BLK_TN_MAX_MSG) 3372db270a8SFrederic Weisbecker return -EINVAL; 3382db270a8SFrederic Weisbecker 339a4b3ada8SCarl Henrik Lunde msg = kmalloc(count + 1, GFP_KERNEL); 3402db270a8SFrederic Weisbecker if (msg == NULL) 3412db270a8SFrederic Weisbecker return -ENOMEM; 3422db270a8SFrederic Weisbecker 3432db270a8SFrederic Weisbecker if (copy_from_user(msg, buffer, count)) { 3442db270a8SFrederic Weisbecker kfree(msg); 3452db270a8SFrederic Weisbecker return -EFAULT; 3462db270a8SFrederic Weisbecker } 3472db270a8SFrederic Weisbecker 348a4b3ada8SCarl Henrik Lunde msg[count] = '\0'; 3492db270a8SFrederic Weisbecker bt = filp->private_data; 3502db270a8SFrederic Weisbecker __trace_note_message(bt, "%s", msg); 3512db270a8SFrederic Weisbecker kfree(msg); 3522db270a8SFrederic Weisbecker 3532db270a8SFrederic Weisbecker return count; 3542db270a8SFrederic Weisbecker } 3552db270a8SFrederic Weisbecker 3562db270a8SFrederic Weisbecker static const struct file_operations blk_msg_fops = { 3572db270a8SFrederic Weisbecker .owner = THIS_MODULE, 3582db270a8SFrederic Weisbecker .open = blk_msg_open, 3592db270a8SFrederic Weisbecker .write = blk_msg_write, 3602db270a8SFrederic Weisbecker }; 3612db270a8SFrederic Weisbecker 3622db270a8SFrederic Weisbecker /* 3632db270a8SFrederic Weisbecker * Keep track of how many times we encountered a full subbuffer, to aid 3642db270a8SFrederic Weisbecker * the user space app in telling how many lost events there were. 3652db270a8SFrederic Weisbecker */ 3662db270a8SFrederic Weisbecker static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, 3672db270a8SFrederic Weisbecker void *prev_subbuf, size_t prev_padding) 3682db270a8SFrederic Weisbecker { 3692db270a8SFrederic Weisbecker struct blk_trace *bt; 3702db270a8SFrederic Weisbecker 3712db270a8SFrederic Weisbecker if (!relay_buf_full(buf)) 3722db270a8SFrederic Weisbecker return 1; 3732db270a8SFrederic Weisbecker 3742db270a8SFrederic Weisbecker bt = buf->chan->private_data; 3752db270a8SFrederic Weisbecker atomic_inc(&bt->dropped); 3762db270a8SFrederic Weisbecker return 0; 3772db270a8SFrederic Weisbecker } 3782db270a8SFrederic Weisbecker 3792db270a8SFrederic Weisbecker static int blk_remove_buf_file_callback(struct dentry *dentry) 3802db270a8SFrederic Weisbecker { 3812db270a8SFrederic Weisbecker struct dentry *parent = dentry->d_parent; 3822db270a8SFrederic Weisbecker debugfs_remove(dentry); 3832db270a8SFrederic Weisbecker 3842db270a8SFrederic Weisbecker /* 3852db270a8SFrederic Weisbecker * this will fail for all but the last file, but that is ok. what we 3862db270a8SFrederic Weisbecker * care about is the top level buts->name directory going away, when 3872db270a8SFrederic Weisbecker * the last trace file is gone. Then we don't have to rmdir() that 3882db270a8SFrederic Weisbecker * manually on trace stop, so it nicely solves the issue with 3892db270a8SFrederic Weisbecker * force killing of running traces. 3902db270a8SFrederic Weisbecker */ 3912db270a8SFrederic Weisbecker 3922db270a8SFrederic Weisbecker debugfs_remove(parent); 3932db270a8SFrederic Weisbecker return 0; 3942db270a8SFrederic Weisbecker } 3952db270a8SFrederic Weisbecker 3962db270a8SFrederic Weisbecker static struct dentry *blk_create_buf_file_callback(const char *filename, 3972db270a8SFrederic Weisbecker struct dentry *parent, 3982db270a8SFrederic Weisbecker int mode, 3992db270a8SFrederic Weisbecker struct rchan_buf *buf, 4002db270a8SFrederic Weisbecker int *is_global) 4012db270a8SFrederic Weisbecker { 4022db270a8SFrederic Weisbecker return debugfs_create_file(filename, mode, parent, buf, 4032db270a8SFrederic Weisbecker &relay_file_operations); 4042db270a8SFrederic Weisbecker } 4052db270a8SFrederic Weisbecker 4062db270a8SFrederic Weisbecker static struct rchan_callbacks blk_relay_callbacks = { 4072db270a8SFrederic Weisbecker .subbuf_start = blk_subbuf_start_callback, 4082db270a8SFrederic Weisbecker .create_buf_file = blk_create_buf_file_callback, 4092db270a8SFrederic Weisbecker .remove_buf_file = blk_remove_buf_file_callback, 4102db270a8SFrederic Weisbecker }; 4112db270a8SFrederic Weisbecker 4129908c309SLi Zefan static void blk_trace_setup_lba(struct blk_trace *bt, 4139908c309SLi Zefan struct block_device *bdev) 4149908c309SLi Zefan { 4159908c309SLi Zefan struct hd_struct *part = NULL; 4169908c309SLi Zefan 4179908c309SLi Zefan if (bdev) 4189908c309SLi Zefan part = bdev->bd_part; 4199908c309SLi Zefan 4209908c309SLi Zefan if (part) { 4219908c309SLi Zefan bt->start_lba = part->start_sect; 4229908c309SLi Zefan bt->end_lba = part->start_sect + part->nr_sects; 4239908c309SLi Zefan } else { 4249908c309SLi Zefan bt->start_lba = 0; 4259908c309SLi Zefan bt->end_lba = -1ULL; 4269908c309SLi Zefan } 4279908c309SLi Zefan } 4289908c309SLi Zefan 4292db270a8SFrederic Weisbecker /* 4302db270a8SFrederic Weisbecker * Setup everything required to start tracing 4312db270a8SFrederic Weisbecker */ 4322db270a8SFrederic Weisbecker int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 433d0deef5bSShawn Du struct block_device *bdev, 4342db270a8SFrederic Weisbecker struct blk_user_trace_setup *buts) 4352db270a8SFrederic Weisbecker { 4362db270a8SFrederic Weisbecker struct blk_trace *old_bt, *bt = NULL; 4372db270a8SFrederic Weisbecker struct dentry *dir = NULL; 4382db270a8SFrederic Weisbecker int ret, i; 4392db270a8SFrederic Weisbecker 4402db270a8SFrederic Weisbecker if (!buts->buf_size || !buts->buf_nr) 4412db270a8SFrederic Weisbecker return -EINVAL; 4422db270a8SFrederic Weisbecker 4432db270a8SFrederic Weisbecker strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); 4442db270a8SFrederic Weisbecker buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; 4452db270a8SFrederic Weisbecker 4462db270a8SFrederic Weisbecker /* 4472db270a8SFrederic Weisbecker * some device names have larger paths - convert the slashes 4482db270a8SFrederic Weisbecker * to underscores for this to work as expected 4492db270a8SFrederic Weisbecker */ 4502db270a8SFrederic Weisbecker for (i = 0; i < strlen(buts->name); i++) 4512db270a8SFrederic Weisbecker if (buts->name[i] == '/') 4522db270a8SFrederic Weisbecker buts->name[i] = '_'; 4532db270a8SFrederic Weisbecker 4542db270a8SFrederic Weisbecker bt = kzalloc(sizeof(*bt), GFP_KERNEL); 4552db270a8SFrederic Weisbecker if (!bt) 456ad5dd549SLi Zefan return -ENOMEM; 4572db270a8SFrederic Weisbecker 458ad5dd549SLi Zefan ret = -ENOMEM; 4592db270a8SFrederic Weisbecker bt->sequence = alloc_percpu(unsigned long); 4602db270a8SFrederic Weisbecker if (!bt->sequence) 4612db270a8SFrederic Weisbecker goto err; 4622db270a8SFrederic Weisbecker 463f0ef0398SIngo Molnar bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); 4642db270a8SFrederic Weisbecker if (!bt->msg_data) 4652db270a8SFrederic Weisbecker goto err; 4662db270a8SFrederic Weisbecker 4672db270a8SFrederic Weisbecker ret = -ENOENT; 4682db270a8SFrederic Weisbecker 469b5230b56SLi Zefan mutex_lock(&blk_tree_mutex); 4702db270a8SFrederic Weisbecker if (!blk_tree_root) { 4712db270a8SFrederic Weisbecker blk_tree_root = debugfs_create_dir("block", NULL); 472b5230b56SLi Zefan if (!blk_tree_root) { 473b5230b56SLi Zefan mutex_unlock(&blk_tree_mutex); 4741a17662eSLi Zefan goto err; 4752db270a8SFrederic Weisbecker } 476b5230b56SLi Zefan } 477b5230b56SLi Zefan mutex_unlock(&blk_tree_mutex); 4782db270a8SFrederic Weisbecker 4792db270a8SFrederic Weisbecker dir = debugfs_create_dir(buts->name, blk_tree_root); 4802db270a8SFrederic Weisbecker 4812db270a8SFrederic Weisbecker if (!dir) 4822db270a8SFrederic Weisbecker goto err; 4832db270a8SFrederic Weisbecker 4842db270a8SFrederic Weisbecker bt->dir = dir; 4852db270a8SFrederic Weisbecker bt->dev = dev; 4862db270a8SFrederic Weisbecker atomic_set(&bt->dropped, 0); 4872db270a8SFrederic Weisbecker 4882db270a8SFrederic Weisbecker ret = -EIO; 4892db270a8SFrederic Weisbecker bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, 4902db270a8SFrederic Weisbecker &blk_dropped_fops); 4912db270a8SFrederic Weisbecker if (!bt->dropped_file) 4922db270a8SFrederic Weisbecker goto err; 4932db270a8SFrederic Weisbecker 4942db270a8SFrederic Weisbecker bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); 4952db270a8SFrederic Weisbecker if (!bt->msg_file) 4962db270a8SFrederic Weisbecker goto err; 4972db270a8SFrederic Weisbecker 4982db270a8SFrederic Weisbecker bt->rchan = relay_open("trace", dir, buts->buf_size, 4992db270a8SFrederic Weisbecker buts->buf_nr, &blk_relay_callbacks, bt); 5002db270a8SFrederic Weisbecker if (!bt->rchan) 5012db270a8SFrederic Weisbecker goto err; 5022db270a8SFrederic Weisbecker 5032db270a8SFrederic Weisbecker bt->act_mask = buts->act_mask; 5042db270a8SFrederic Weisbecker if (!bt->act_mask) 5052db270a8SFrederic Weisbecker bt->act_mask = (u16) -1; 5062db270a8SFrederic Weisbecker 5079908c309SLi Zefan blk_trace_setup_lba(bt, bdev); 5082db270a8SFrederic Weisbecker 509d0deef5bSShawn Du /* overwrite with user settings */ 510d0deef5bSShawn Du if (buts->start_lba) 511d0deef5bSShawn Du bt->start_lba = buts->start_lba; 512d0deef5bSShawn Du if (buts->end_lba) 513d0deef5bSShawn Du bt->end_lba = buts->end_lba; 514d0deef5bSShawn Du 5152db270a8SFrederic Weisbecker bt->pid = buts->pid; 5162db270a8SFrederic Weisbecker bt->trace_state = Blktrace_setup; 5172db270a8SFrederic Weisbecker 5182db270a8SFrederic Weisbecker ret = -EBUSY; 5192db270a8SFrederic Weisbecker old_bt = xchg(&q->blk_trace, bt); 5202db270a8SFrederic Weisbecker if (old_bt) { 5212db270a8SFrederic Weisbecker (void) xchg(&q->blk_trace, old_bt); 5222db270a8SFrederic Weisbecker goto err; 5232db270a8SFrederic Weisbecker } 5242db270a8SFrederic Weisbecker 52517ba97e3SLi Zefan if (atomic_inc_return(&blk_probes_ref) == 1) 526cbe28296SLi Zefan blk_register_tracepoints(); 527cbe28296SLi Zefan 5282db270a8SFrederic Weisbecker return 0; 5292db270a8SFrederic Weisbecker err: 530ad5dd549SLi Zefan blk_trace_free(bt); 5312db270a8SFrederic Weisbecker return ret; 5322db270a8SFrederic Weisbecker } 5332db270a8SFrederic Weisbecker 5342db270a8SFrederic Weisbecker int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 535d0deef5bSShawn Du struct block_device *bdev, 5362db270a8SFrederic Weisbecker char __user *arg) 5372db270a8SFrederic Weisbecker { 5382db270a8SFrederic Weisbecker struct blk_user_trace_setup buts; 5392db270a8SFrederic Weisbecker int ret; 5402db270a8SFrederic Weisbecker 5412db270a8SFrederic Weisbecker ret = copy_from_user(&buts, arg, sizeof(buts)); 5422db270a8SFrederic Weisbecker if (ret) 5432db270a8SFrederic Weisbecker return -EFAULT; 5442db270a8SFrederic Weisbecker 545d0deef5bSShawn Du ret = do_blk_trace_setup(q, name, dev, bdev, &buts); 5462db270a8SFrederic Weisbecker if (ret) 5472db270a8SFrederic Weisbecker return ret; 5482db270a8SFrederic Weisbecker 5492db270a8SFrederic Weisbecker if (copy_to_user(arg, &buts, sizeof(buts))) 5502db270a8SFrederic Weisbecker return -EFAULT; 5512db270a8SFrederic Weisbecker 5522db270a8SFrederic Weisbecker return 0; 5532db270a8SFrederic Weisbecker } 5542db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_setup); 5552db270a8SFrederic Weisbecker 5562db270a8SFrederic Weisbecker int blk_trace_startstop(struct request_queue *q, int start) 5572db270a8SFrederic Weisbecker { 5582db270a8SFrederic Weisbecker int ret; 5592db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 5602db270a8SFrederic Weisbecker 5612db270a8SFrederic Weisbecker if (bt == NULL) 5622db270a8SFrederic Weisbecker return -EINVAL; 5632db270a8SFrederic Weisbecker 5642db270a8SFrederic Weisbecker /* 5652db270a8SFrederic Weisbecker * For starting a trace, we can transition from a setup or stopped 5662db270a8SFrederic Weisbecker * trace. For stopping a trace, the state must be running 5672db270a8SFrederic Weisbecker */ 5682db270a8SFrederic Weisbecker ret = -EINVAL; 5692db270a8SFrederic Weisbecker if (start) { 5702db270a8SFrederic Weisbecker if (bt->trace_state == Blktrace_setup || 5712db270a8SFrederic Weisbecker bt->trace_state == Blktrace_stopped) { 5722db270a8SFrederic Weisbecker blktrace_seq++; 5732db270a8SFrederic Weisbecker smp_mb(); 5742db270a8SFrederic Weisbecker bt->trace_state = Blktrace_running; 5752db270a8SFrederic Weisbecker 5762db270a8SFrederic Weisbecker trace_note_time(bt); 5772db270a8SFrederic Weisbecker ret = 0; 5782db270a8SFrederic Weisbecker } 5792db270a8SFrederic Weisbecker } else { 5802db270a8SFrederic Weisbecker if (bt->trace_state == Blktrace_running) { 5812db270a8SFrederic Weisbecker bt->trace_state = Blktrace_stopped; 5822db270a8SFrederic Weisbecker relay_flush(bt->rchan); 5832db270a8SFrederic Weisbecker ret = 0; 5842db270a8SFrederic Weisbecker } 5852db270a8SFrederic Weisbecker } 5862db270a8SFrederic Weisbecker 5872db270a8SFrederic Weisbecker return ret; 5882db270a8SFrederic Weisbecker } 5892db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_trace_startstop); 5902db270a8SFrederic Weisbecker 5912db270a8SFrederic Weisbecker /** 5922db270a8SFrederic Weisbecker * blk_trace_ioctl: - handle the ioctls associated with tracing 5932db270a8SFrederic Weisbecker * @bdev: the block device 5942db270a8SFrederic Weisbecker * @cmd: the ioctl cmd 5952db270a8SFrederic Weisbecker * @arg: the argument data, if any 5962db270a8SFrederic Weisbecker * 5972db270a8SFrederic Weisbecker **/ 5982db270a8SFrederic Weisbecker int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) 5992db270a8SFrederic Weisbecker { 6002db270a8SFrederic Weisbecker struct request_queue *q; 6012db270a8SFrederic Weisbecker int ret, start = 0; 6022db270a8SFrederic Weisbecker char b[BDEVNAME_SIZE]; 6032db270a8SFrederic Weisbecker 6042db270a8SFrederic Weisbecker q = bdev_get_queue(bdev); 6052db270a8SFrederic Weisbecker if (!q) 6062db270a8SFrederic Weisbecker return -ENXIO; 6072db270a8SFrederic Weisbecker 6082db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 6092db270a8SFrederic Weisbecker 6102db270a8SFrederic Weisbecker switch (cmd) { 6112db270a8SFrederic Weisbecker case BLKTRACESETUP: 6122db270a8SFrederic Weisbecker bdevname(bdev, b); 613d0deef5bSShawn Du ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); 6142db270a8SFrederic Weisbecker break; 6152db270a8SFrederic Weisbecker case BLKTRACESTART: 6162db270a8SFrederic Weisbecker start = 1; 6172db270a8SFrederic Weisbecker case BLKTRACESTOP: 6182db270a8SFrederic Weisbecker ret = blk_trace_startstop(q, start); 6192db270a8SFrederic Weisbecker break; 6202db270a8SFrederic Weisbecker case BLKTRACETEARDOWN: 6212db270a8SFrederic Weisbecker ret = blk_trace_remove(q); 6222db270a8SFrederic Weisbecker break; 6232db270a8SFrederic Weisbecker default: 6242db270a8SFrederic Weisbecker ret = -ENOTTY; 6252db270a8SFrederic Weisbecker break; 6262db270a8SFrederic Weisbecker } 6272db270a8SFrederic Weisbecker 6282db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 6292db270a8SFrederic Weisbecker return ret; 6302db270a8SFrederic Weisbecker } 6312db270a8SFrederic Weisbecker 6322db270a8SFrederic Weisbecker /** 6332db270a8SFrederic Weisbecker * blk_trace_shutdown: - stop and cleanup trace structures 6342db270a8SFrederic Weisbecker * @q: the request queue associated with the device 6352db270a8SFrederic Weisbecker * 6362db270a8SFrederic Weisbecker **/ 6372db270a8SFrederic Weisbecker void blk_trace_shutdown(struct request_queue *q) 6382db270a8SFrederic Weisbecker { 6392db270a8SFrederic Weisbecker if (q->blk_trace) { 6402db270a8SFrederic Weisbecker blk_trace_startstop(q, 0); 6412db270a8SFrederic Weisbecker blk_trace_remove(q); 6422db270a8SFrederic Weisbecker } 6432db270a8SFrederic Weisbecker } 6442db270a8SFrederic Weisbecker 6452db270a8SFrederic Weisbecker /* 6462db270a8SFrederic Weisbecker * blktrace probes 6472db270a8SFrederic Weisbecker */ 6482db270a8SFrederic Weisbecker 6492db270a8SFrederic Weisbecker /** 6502db270a8SFrederic Weisbecker * blk_add_trace_rq - Add a trace for a request oriented action 6512db270a8SFrederic Weisbecker * @q: queue the io is for 6522db270a8SFrederic Weisbecker * @rq: the source request 6532db270a8SFrederic Weisbecker * @what: the action 6542db270a8SFrederic Weisbecker * 6552db270a8SFrederic Weisbecker * Description: 6562db270a8SFrederic Weisbecker * Records an action against a request. Will log the bio offset + size. 6572db270a8SFrederic Weisbecker * 6582db270a8SFrederic Weisbecker **/ 6592db270a8SFrederic Weisbecker static void blk_add_trace_rq(struct request_queue *q, struct request *rq, 6602db270a8SFrederic Weisbecker u32 what) 6612db270a8SFrederic Weisbecker { 6622db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 6632db270a8SFrederic Weisbecker int rw = rq->cmd_flags & 0x03; 6642db270a8SFrederic Weisbecker 6652db270a8SFrederic Weisbecker if (likely(!bt)) 6662db270a8SFrederic Weisbecker return; 6672db270a8SFrederic Weisbecker 6682db270a8SFrederic Weisbecker if (blk_discard_rq(rq)) 6692db270a8SFrederic Weisbecker rw |= (1 << BIO_RW_DISCARD); 6702db270a8SFrederic Weisbecker 6712db270a8SFrederic Weisbecker if (blk_pc_request(rq)) { 6722db270a8SFrederic Weisbecker what |= BLK_TC_ACT(BLK_TC_PC); 6732e46e8b2STejun Heo __blk_add_trace(bt, 0, blk_rq_bytes(rq), rw, 6742e46e8b2STejun Heo what, rq->errors, rq->cmd_len, rq->cmd); 6752db270a8SFrederic Weisbecker } else { 6762db270a8SFrederic Weisbecker what |= BLK_TC_ACT(BLK_TC_FS); 6772e46e8b2STejun Heo __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), rw, 6782e46e8b2STejun Heo what, rq->errors, 0, NULL); 6792db270a8SFrederic Weisbecker } 6802db270a8SFrederic Weisbecker } 6812db270a8SFrederic Weisbecker 6822db270a8SFrederic Weisbecker static void blk_add_trace_rq_abort(struct request_queue *q, struct request *rq) 6832db270a8SFrederic Weisbecker { 6842db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_ABORT); 6852db270a8SFrederic Weisbecker } 6862db270a8SFrederic Weisbecker 6872db270a8SFrederic Weisbecker static void blk_add_trace_rq_insert(struct request_queue *q, struct request *rq) 6882db270a8SFrederic Weisbecker { 6892db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_INSERT); 6902db270a8SFrederic Weisbecker } 6912db270a8SFrederic Weisbecker 6922db270a8SFrederic Weisbecker static void blk_add_trace_rq_issue(struct request_queue *q, struct request *rq) 6932db270a8SFrederic Weisbecker { 6942db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_ISSUE); 6952db270a8SFrederic Weisbecker } 6962db270a8SFrederic Weisbecker 6972db270a8SFrederic Weisbecker static void blk_add_trace_rq_requeue(struct request_queue *q, 6982db270a8SFrederic Weisbecker struct request *rq) 6992db270a8SFrederic Weisbecker { 7002db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); 7012db270a8SFrederic Weisbecker } 7022db270a8SFrederic Weisbecker 7032db270a8SFrederic Weisbecker static void blk_add_trace_rq_complete(struct request_queue *q, 7042db270a8SFrederic Weisbecker struct request *rq) 7052db270a8SFrederic Weisbecker { 7062db270a8SFrederic Weisbecker blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); 7072db270a8SFrederic Weisbecker } 7082db270a8SFrederic Weisbecker 7092db270a8SFrederic Weisbecker /** 7102db270a8SFrederic Weisbecker * blk_add_trace_bio - Add a trace for a bio oriented action 7112db270a8SFrederic Weisbecker * @q: queue the io is for 7122db270a8SFrederic Weisbecker * @bio: the source bio 7132db270a8SFrederic Weisbecker * @what: the action 7142db270a8SFrederic Weisbecker * 7152db270a8SFrederic Weisbecker * Description: 7162db270a8SFrederic Weisbecker * Records an action against a bio. Will log the bio offset + size. 7172db270a8SFrederic Weisbecker * 7182db270a8SFrederic Weisbecker **/ 7192db270a8SFrederic Weisbecker static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, 7202db270a8SFrederic Weisbecker u32 what) 7212db270a8SFrederic Weisbecker { 7222db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7232db270a8SFrederic Weisbecker 7242db270a8SFrederic Weisbecker if (likely(!bt)) 7252db270a8SFrederic Weisbecker return; 7262db270a8SFrederic Weisbecker 7272db270a8SFrederic Weisbecker __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, 7282db270a8SFrederic Weisbecker !bio_flagged(bio, BIO_UPTODATE), 0, NULL); 7292db270a8SFrederic Weisbecker } 7302db270a8SFrederic Weisbecker 7312db270a8SFrederic Weisbecker static void blk_add_trace_bio_bounce(struct request_queue *q, struct bio *bio) 7322db270a8SFrederic Weisbecker { 7332db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); 7342db270a8SFrederic Weisbecker } 7352db270a8SFrederic Weisbecker 7362db270a8SFrederic Weisbecker static void blk_add_trace_bio_complete(struct request_queue *q, struct bio *bio) 7372db270a8SFrederic Weisbecker { 7382db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); 7392db270a8SFrederic Weisbecker } 7402db270a8SFrederic Weisbecker 7412db270a8SFrederic Weisbecker static void blk_add_trace_bio_backmerge(struct request_queue *q, 7422db270a8SFrederic Weisbecker struct bio *bio) 7432db270a8SFrederic Weisbecker { 7442db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); 7452db270a8SFrederic Weisbecker } 7462db270a8SFrederic Weisbecker 7472db270a8SFrederic Weisbecker static void blk_add_trace_bio_frontmerge(struct request_queue *q, 7482db270a8SFrederic Weisbecker struct bio *bio) 7492db270a8SFrederic Weisbecker { 7502db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); 7512db270a8SFrederic Weisbecker } 7522db270a8SFrederic Weisbecker 7532db270a8SFrederic Weisbecker static void blk_add_trace_bio_queue(struct request_queue *q, struct bio *bio) 7542db270a8SFrederic Weisbecker { 7552db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_QUEUE); 7562db270a8SFrederic Weisbecker } 7572db270a8SFrederic Weisbecker 7582db270a8SFrederic Weisbecker static void blk_add_trace_getrq(struct request_queue *q, 7592db270a8SFrederic Weisbecker struct bio *bio, int rw) 7602db270a8SFrederic Weisbecker { 7612db270a8SFrederic Weisbecker if (bio) 7622db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_GETRQ); 7632db270a8SFrederic Weisbecker else { 7642db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7652db270a8SFrederic Weisbecker 7662db270a8SFrederic Weisbecker if (bt) 7672db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); 7682db270a8SFrederic Weisbecker } 7692db270a8SFrederic Weisbecker } 7702db270a8SFrederic Weisbecker 7712db270a8SFrederic Weisbecker 7722db270a8SFrederic Weisbecker static void blk_add_trace_sleeprq(struct request_queue *q, 7732db270a8SFrederic Weisbecker struct bio *bio, int rw) 7742db270a8SFrederic Weisbecker { 7752db270a8SFrederic Weisbecker if (bio) 7762db270a8SFrederic Weisbecker blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); 7772db270a8SFrederic Weisbecker else { 7782db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7792db270a8SFrederic Weisbecker 7802db270a8SFrederic Weisbecker if (bt) 7812db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, 7822db270a8SFrederic Weisbecker 0, 0, NULL); 7832db270a8SFrederic Weisbecker } 7842db270a8SFrederic Weisbecker } 7852db270a8SFrederic Weisbecker 7862db270a8SFrederic Weisbecker static void blk_add_trace_plug(struct request_queue *q) 7872db270a8SFrederic Weisbecker { 7882db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7892db270a8SFrederic Weisbecker 7902db270a8SFrederic Weisbecker if (bt) 7912db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); 7922db270a8SFrederic Weisbecker } 7932db270a8SFrederic Weisbecker 7942db270a8SFrederic Weisbecker static void blk_add_trace_unplug_io(struct request_queue *q) 7952db270a8SFrederic Weisbecker { 7962db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 7972db270a8SFrederic Weisbecker 7982db270a8SFrederic Weisbecker if (bt) { 7992db270a8SFrederic Weisbecker unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; 8002db270a8SFrederic Weisbecker __be64 rpdu = cpu_to_be64(pdu); 8012db270a8SFrederic Weisbecker 8022db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, 8032db270a8SFrederic Weisbecker sizeof(rpdu), &rpdu); 8042db270a8SFrederic Weisbecker } 8052db270a8SFrederic Weisbecker } 8062db270a8SFrederic Weisbecker 8072db270a8SFrederic Weisbecker static void blk_add_trace_unplug_timer(struct request_queue *q) 8082db270a8SFrederic Weisbecker { 8092db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8102db270a8SFrederic Weisbecker 8112db270a8SFrederic Weisbecker if (bt) { 8122db270a8SFrederic Weisbecker unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; 8132db270a8SFrederic Weisbecker __be64 rpdu = cpu_to_be64(pdu); 8142db270a8SFrederic Weisbecker 8152db270a8SFrederic Weisbecker __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, 8162db270a8SFrederic Weisbecker sizeof(rpdu), &rpdu); 8172db270a8SFrederic Weisbecker } 8182db270a8SFrederic Weisbecker } 8192db270a8SFrederic Weisbecker 8202db270a8SFrederic Weisbecker static void blk_add_trace_split(struct request_queue *q, struct bio *bio, 8212db270a8SFrederic Weisbecker unsigned int pdu) 8222db270a8SFrederic Weisbecker { 8232db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8242db270a8SFrederic Weisbecker 8252db270a8SFrederic Weisbecker if (bt) { 8262db270a8SFrederic Weisbecker __be64 rpdu = cpu_to_be64(pdu); 8272db270a8SFrederic Weisbecker 8282db270a8SFrederic Weisbecker __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, 8292db270a8SFrederic Weisbecker BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), 8302db270a8SFrederic Weisbecker sizeof(rpdu), &rpdu); 8312db270a8SFrederic Weisbecker } 8322db270a8SFrederic Weisbecker } 8332db270a8SFrederic Weisbecker 8342db270a8SFrederic Weisbecker /** 8352db270a8SFrederic Weisbecker * blk_add_trace_remap - Add a trace for a remap operation 8362db270a8SFrederic Weisbecker * @q: queue the io is for 8372db270a8SFrederic Weisbecker * @bio: the source bio 8382db270a8SFrederic Weisbecker * @dev: target device 839a42aaa3bSAlan D. Brunelle * @from: source sector 8402db270a8SFrederic Weisbecker * 8412db270a8SFrederic Weisbecker * Description: 8422db270a8SFrederic Weisbecker * Device mapper or raid target sometimes need to split a bio because 8432db270a8SFrederic Weisbecker * it spans a stripe (or similar). Add a trace for that action. 8442db270a8SFrederic Weisbecker * 8452db270a8SFrederic Weisbecker **/ 8462db270a8SFrederic Weisbecker static void blk_add_trace_remap(struct request_queue *q, struct bio *bio, 84722a7c31aSAlan D. Brunelle dev_t dev, sector_t from) 8482db270a8SFrederic Weisbecker { 8492db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8502db270a8SFrederic Weisbecker struct blk_io_trace_remap r; 8512db270a8SFrederic Weisbecker 8522db270a8SFrederic Weisbecker if (likely(!bt)) 8532db270a8SFrederic Weisbecker return; 8542db270a8SFrederic Weisbecker 855a42aaa3bSAlan D. Brunelle r.device_from = cpu_to_be32(dev); 856a42aaa3bSAlan D. Brunelle r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); 857a42aaa3bSAlan D. Brunelle r.sector_from = cpu_to_be64(from); 8582db270a8SFrederic Weisbecker 85922a7c31aSAlan D. Brunelle __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, 86022a7c31aSAlan D. Brunelle BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), 86122a7c31aSAlan D. Brunelle sizeof(r), &r); 8622db270a8SFrederic Weisbecker } 8632db270a8SFrederic Weisbecker 8642db270a8SFrederic Weisbecker /** 8652db270a8SFrederic Weisbecker * blk_add_driver_data - Add binary message with driver-specific data 8662db270a8SFrederic Weisbecker * @q: queue the io is for 8672db270a8SFrederic Weisbecker * @rq: io request 8682db270a8SFrederic Weisbecker * @data: driver-specific data 8692db270a8SFrederic Weisbecker * @len: length of driver-specific data 8702db270a8SFrederic Weisbecker * 8712db270a8SFrederic Weisbecker * Description: 8722db270a8SFrederic Weisbecker * Some drivers might want to write driver-specific data per request. 8732db270a8SFrederic Weisbecker * 8742db270a8SFrederic Weisbecker **/ 8752db270a8SFrederic Weisbecker void blk_add_driver_data(struct request_queue *q, 8762db270a8SFrederic Weisbecker struct request *rq, 8772db270a8SFrederic Weisbecker void *data, size_t len) 8782db270a8SFrederic Weisbecker { 8792db270a8SFrederic Weisbecker struct blk_trace *bt = q->blk_trace; 8802db270a8SFrederic Weisbecker 8812db270a8SFrederic Weisbecker if (likely(!bt)) 8822db270a8SFrederic Weisbecker return; 8832db270a8SFrederic Weisbecker 8842db270a8SFrederic Weisbecker if (blk_pc_request(rq)) 8852e46e8b2STejun Heo __blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, 8862e46e8b2STejun Heo BLK_TA_DRV_DATA, rq->errors, len, data); 8872db270a8SFrederic Weisbecker else 8882e46e8b2STejun Heo __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0, 8892e46e8b2STejun Heo BLK_TA_DRV_DATA, rq->errors, len, data); 8902db270a8SFrederic Weisbecker } 8912db270a8SFrederic Weisbecker EXPORT_SYMBOL_GPL(blk_add_driver_data); 8922db270a8SFrederic Weisbecker 8933c289ba7SLi Zefan static void blk_register_tracepoints(void) 8942db270a8SFrederic Weisbecker { 8952db270a8SFrederic Weisbecker int ret; 8962db270a8SFrederic Weisbecker 8972db270a8SFrederic Weisbecker ret = register_trace_block_rq_abort(blk_add_trace_rq_abort); 8982db270a8SFrederic Weisbecker WARN_ON(ret); 8992db270a8SFrederic Weisbecker ret = register_trace_block_rq_insert(blk_add_trace_rq_insert); 9002db270a8SFrederic Weisbecker WARN_ON(ret); 9012db270a8SFrederic Weisbecker ret = register_trace_block_rq_issue(blk_add_trace_rq_issue); 9022db270a8SFrederic Weisbecker WARN_ON(ret); 9032db270a8SFrederic Weisbecker ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue); 9042db270a8SFrederic Weisbecker WARN_ON(ret); 9052db270a8SFrederic Weisbecker ret = register_trace_block_rq_complete(blk_add_trace_rq_complete); 9062db270a8SFrederic Weisbecker WARN_ON(ret); 9072db270a8SFrederic Weisbecker ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce); 9082db270a8SFrederic Weisbecker WARN_ON(ret); 9092db270a8SFrederic Weisbecker ret = register_trace_block_bio_complete(blk_add_trace_bio_complete); 9102db270a8SFrederic Weisbecker WARN_ON(ret); 9112db270a8SFrederic Weisbecker ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); 9122db270a8SFrederic Weisbecker WARN_ON(ret); 9132db270a8SFrederic Weisbecker ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); 9142db270a8SFrederic Weisbecker WARN_ON(ret); 9152db270a8SFrederic Weisbecker ret = register_trace_block_bio_queue(blk_add_trace_bio_queue); 9162db270a8SFrederic Weisbecker WARN_ON(ret); 9172db270a8SFrederic Weisbecker ret = register_trace_block_getrq(blk_add_trace_getrq); 9182db270a8SFrederic Weisbecker WARN_ON(ret); 9192db270a8SFrederic Weisbecker ret = register_trace_block_sleeprq(blk_add_trace_sleeprq); 9202db270a8SFrederic Weisbecker WARN_ON(ret); 9212db270a8SFrederic Weisbecker ret = register_trace_block_plug(blk_add_trace_plug); 9222db270a8SFrederic Weisbecker WARN_ON(ret); 9232db270a8SFrederic Weisbecker ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer); 9242db270a8SFrederic Weisbecker WARN_ON(ret); 9252db270a8SFrederic Weisbecker ret = register_trace_block_unplug_io(blk_add_trace_unplug_io); 9262db270a8SFrederic Weisbecker WARN_ON(ret); 9272db270a8SFrederic Weisbecker ret = register_trace_block_split(blk_add_trace_split); 9282db270a8SFrederic Weisbecker WARN_ON(ret); 9292db270a8SFrederic Weisbecker ret = register_trace_block_remap(blk_add_trace_remap); 9302db270a8SFrederic Weisbecker WARN_ON(ret); 9312db270a8SFrederic Weisbecker } 9322db270a8SFrederic Weisbecker 9332db270a8SFrederic Weisbecker static void blk_unregister_tracepoints(void) 9342db270a8SFrederic Weisbecker { 9352db270a8SFrederic Weisbecker unregister_trace_block_remap(blk_add_trace_remap); 9362db270a8SFrederic Weisbecker unregister_trace_block_split(blk_add_trace_split); 9372db270a8SFrederic Weisbecker unregister_trace_block_unplug_io(blk_add_trace_unplug_io); 9382db270a8SFrederic Weisbecker unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer); 9392db270a8SFrederic Weisbecker unregister_trace_block_plug(blk_add_trace_plug); 9402db270a8SFrederic Weisbecker unregister_trace_block_sleeprq(blk_add_trace_sleeprq); 9412db270a8SFrederic Weisbecker unregister_trace_block_getrq(blk_add_trace_getrq); 9422db270a8SFrederic Weisbecker unregister_trace_block_bio_queue(blk_add_trace_bio_queue); 9432db270a8SFrederic Weisbecker unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); 9442db270a8SFrederic Weisbecker unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); 9452db270a8SFrederic Weisbecker unregister_trace_block_bio_complete(blk_add_trace_bio_complete); 9462db270a8SFrederic Weisbecker unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce); 9472db270a8SFrederic Weisbecker unregister_trace_block_rq_complete(blk_add_trace_rq_complete); 9482db270a8SFrederic Weisbecker unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue); 9492db270a8SFrederic Weisbecker unregister_trace_block_rq_issue(blk_add_trace_rq_issue); 9502db270a8SFrederic Weisbecker unregister_trace_block_rq_insert(blk_add_trace_rq_insert); 9512db270a8SFrederic Weisbecker unregister_trace_block_rq_abort(blk_add_trace_rq_abort); 9522db270a8SFrederic Weisbecker 9532db270a8SFrederic Weisbecker tracepoint_synchronize_unregister(); 9542db270a8SFrederic Weisbecker } 9552db270a8SFrederic Weisbecker 9562db270a8SFrederic Weisbecker /* 9572db270a8SFrederic Weisbecker * struct blk_io_tracer formatting routines 9582db270a8SFrederic Weisbecker */ 9592db270a8SFrederic Weisbecker 9602db270a8SFrederic Weisbecker static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) 9612db270a8SFrederic Weisbecker { 9622db270a8SFrederic Weisbecker int i = 0; 96365796348SLi Zefan int tc = t->action >> BLK_TC_SHIFT; 9642db270a8SFrederic Weisbecker 96518cea459SLi Zefan if (t->action == BLK_TN_MESSAGE) { 96618cea459SLi Zefan rwbs[i++] = 'N'; 96718cea459SLi Zefan goto out; 96818cea459SLi Zefan } 96918cea459SLi Zefan 97065796348SLi Zefan if (tc & BLK_TC_DISCARD) 9712db270a8SFrederic Weisbecker rwbs[i++] = 'D'; 97265796348SLi Zefan else if (tc & BLK_TC_WRITE) 9732db270a8SFrederic Weisbecker rwbs[i++] = 'W'; 9742db270a8SFrederic Weisbecker else if (t->bytes) 9752db270a8SFrederic Weisbecker rwbs[i++] = 'R'; 9762db270a8SFrederic Weisbecker else 9772db270a8SFrederic Weisbecker rwbs[i++] = 'N'; 9782db270a8SFrederic Weisbecker 97965796348SLi Zefan if (tc & BLK_TC_AHEAD) 9802db270a8SFrederic Weisbecker rwbs[i++] = 'A'; 98165796348SLi Zefan if (tc & BLK_TC_BARRIER) 9822db270a8SFrederic Weisbecker rwbs[i++] = 'B'; 98365796348SLi Zefan if (tc & BLK_TC_SYNC) 9842db270a8SFrederic Weisbecker rwbs[i++] = 'S'; 98565796348SLi Zefan if (tc & BLK_TC_META) 9862db270a8SFrederic Weisbecker rwbs[i++] = 'M'; 98718cea459SLi Zefan out: 9882db270a8SFrederic Weisbecker rwbs[i] = '\0'; 9892db270a8SFrederic Weisbecker } 9902db270a8SFrederic Weisbecker 9912db270a8SFrederic Weisbecker static inline 9922db270a8SFrederic Weisbecker const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) 9932db270a8SFrederic Weisbecker { 9942db270a8SFrederic Weisbecker return (const struct blk_io_trace *)ent; 9952db270a8SFrederic Weisbecker } 9962db270a8SFrederic Weisbecker 9972db270a8SFrederic Weisbecker static inline const void *pdu_start(const struct trace_entry *ent) 9982db270a8SFrederic Weisbecker { 9992db270a8SFrederic Weisbecker return te_blk_io_trace(ent) + 1; 10002db270a8SFrederic Weisbecker } 10012db270a8SFrederic Weisbecker 100266de7792SLi Zefan static inline u32 t_action(const struct trace_entry *ent) 100366de7792SLi Zefan { 100466de7792SLi Zefan return te_blk_io_trace(ent)->action; 100566de7792SLi Zefan } 100666de7792SLi Zefan 100766de7792SLi Zefan static inline u32 t_bytes(const struct trace_entry *ent) 100866de7792SLi Zefan { 100966de7792SLi Zefan return te_blk_io_trace(ent)->bytes; 101066de7792SLi Zefan } 101166de7792SLi Zefan 10122db270a8SFrederic Weisbecker static inline u32 t_sec(const struct trace_entry *ent) 10132db270a8SFrederic Weisbecker { 10142db270a8SFrederic Weisbecker return te_blk_io_trace(ent)->bytes >> 9; 10152db270a8SFrederic Weisbecker } 10162db270a8SFrederic Weisbecker 10172db270a8SFrederic Weisbecker static inline unsigned long long t_sector(const struct trace_entry *ent) 10182db270a8SFrederic Weisbecker { 10192db270a8SFrederic Weisbecker return te_blk_io_trace(ent)->sector; 10202db270a8SFrederic Weisbecker } 10212db270a8SFrederic Weisbecker 10222db270a8SFrederic Weisbecker static inline __u16 t_error(const struct trace_entry *ent) 10232db270a8SFrederic Weisbecker { 1024e0dc81beSLi Zefan return te_blk_io_trace(ent)->error; 10252db270a8SFrederic Weisbecker } 10262db270a8SFrederic Weisbecker 10272db270a8SFrederic Weisbecker static __u64 get_pdu_int(const struct trace_entry *ent) 10282db270a8SFrederic Weisbecker { 10292db270a8SFrederic Weisbecker const __u64 *val = pdu_start(ent); 10302db270a8SFrederic Weisbecker return be64_to_cpu(*val); 10312db270a8SFrederic Weisbecker } 10322db270a8SFrederic Weisbecker 10332db270a8SFrederic Weisbecker static void get_pdu_remap(const struct trace_entry *ent, 10342db270a8SFrederic Weisbecker struct blk_io_trace_remap *r) 10352db270a8SFrederic Weisbecker { 10362db270a8SFrederic Weisbecker const struct blk_io_trace_remap *__r = pdu_start(ent); 1037a42aaa3bSAlan D. Brunelle __u64 sector_from = __r->sector_from; 10382db270a8SFrederic Weisbecker 10392db270a8SFrederic Weisbecker r->device_from = be32_to_cpu(__r->device_from); 1040a42aaa3bSAlan D. Brunelle r->device_to = be32_to_cpu(__r->device_to); 1041a42aaa3bSAlan D. Brunelle r->sector_from = be64_to_cpu(sector_from); 10422db270a8SFrederic Weisbecker } 10432db270a8SFrederic Weisbecker 1044b6a4b0c3SLi Zefan typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); 1045b6a4b0c3SLi Zefan 1046b6a4b0c3SLi Zefan static int blk_log_action_classic(struct trace_iterator *iter, const char *act) 10472db270a8SFrederic Weisbecker { 10482db270a8SFrederic Weisbecker char rwbs[6]; 104935ac51bfSLi Zefan unsigned long long ts = iter->ts; 105035ac51bfSLi Zefan unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); 10512db270a8SFrederic Weisbecker unsigned secs = (unsigned long)ts; 1052b6a4b0c3SLi Zefan const struct blk_io_trace *t = te_blk_io_trace(iter->ent); 10532db270a8SFrederic Weisbecker 10542db270a8SFrederic Weisbecker fill_rwbs(rwbs, t); 10552db270a8SFrederic Weisbecker 10562db270a8SFrederic Weisbecker return trace_seq_printf(&iter->seq, 105735ac51bfSLi Zefan "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ", 10582db270a8SFrederic Weisbecker MAJOR(t->device), MINOR(t->device), iter->cpu, 1059b6a4b0c3SLi Zefan secs, nsec_rem, iter->ent->pid, act, rwbs); 10602db270a8SFrederic Weisbecker } 10612db270a8SFrederic Weisbecker 1062b6a4b0c3SLi Zefan static int blk_log_action(struct trace_iterator *iter, const char *act) 10632db270a8SFrederic Weisbecker { 10642db270a8SFrederic Weisbecker char rwbs[6]; 1065b6a4b0c3SLi Zefan const struct blk_io_trace *t = te_blk_io_trace(iter->ent); 1066b6a4b0c3SLi Zefan 10672db270a8SFrederic Weisbecker fill_rwbs(rwbs, t); 1068b6a4b0c3SLi Zefan return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ", 10692db270a8SFrederic Weisbecker MAJOR(t->device), MINOR(t->device), act, rwbs); 10702db270a8SFrederic Weisbecker } 10712db270a8SFrederic Weisbecker 107266de7792SLi Zefan static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent) 107366de7792SLi Zefan { 107404986257SLi Zefan const unsigned char *pdu_buf; 107566de7792SLi Zefan int pdu_len; 107666de7792SLi Zefan int i, end, ret; 107766de7792SLi Zefan 107866de7792SLi Zefan pdu_buf = pdu_start(ent); 107966de7792SLi Zefan pdu_len = te_blk_io_trace(ent)->pdu_len; 108066de7792SLi Zefan 108166de7792SLi Zefan if (!pdu_len) 108266de7792SLi Zefan return 1; 108366de7792SLi Zefan 108466de7792SLi Zefan /* find the last zero that needs to be printed */ 108566de7792SLi Zefan for (end = pdu_len - 1; end >= 0; end--) 108666de7792SLi Zefan if (pdu_buf[end]) 108766de7792SLi Zefan break; 108866de7792SLi Zefan end++; 108966de7792SLi Zefan 109066de7792SLi Zefan if (!trace_seq_putc(s, '(')) 109166de7792SLi Zefan return 0; 109266de7792SLi Zefan 109366de7792SLi Zefan for (i = 0; i < pdu_len; i++) { 109466de7792SLi Zefan 109566de7792SLi Zefan ret = trace_seq_printf(s, "%s%02x", 109666de7792SLi Zefan i == 0 ? "" : " ", pdu_buf[i]); 109766de7792SLi Zefan if (!ret) 109866de7792SLi Zefan return ret; 109966de7792SLi Zefan 110066de7792SLi Zefan /* 110166de7792SLi Zefan * stop when the rest is just zeroes and indicate so 110266de7792SLi Zefan * with a ".." appended 110366de7792SLi Zefan */ 110466de7792SLi Zefan if (i == end && end != pdu_len - 1) 110566de7792SLi Zefan return trace_seq_puts(s, " ..) "); 110666de7792SLi Zefan } 110766de7792SLi Zefan 110866de7792SLi Zefan return trace_seq_puts(s, ") "); 110966de7792SLi Zefan } 111066de7792SLi Zefan 11112db270a8SFrederic Weisbecker static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) 11122db270a8SFrederic Weisbecker { 11134ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 11144ca53085SSteven Rostedt 11154ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 11162db270a8SFrederic Weisbecker 111766de7792SLi Zefan if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { 111866de7792SLi Zefan int ret; 111966de7792SLi Zefan 112066de7792SLi Zefan ret = trace_seq_printf(s, "%u ", t_bytes(ent)); 112166de7792SLi Zefan if (!ret) 112266de7792SLi Zefan return 0; 112366de7792SLi Zefan ret = blk_log_dump_pdu(s, ent); 112466de7792SLi Zefan if (!ret) 112566de7792SLi Zefan return 0; 112666de7792SLi Zefan return trace_seq_printf(s, "[%s]\n", cmd); 112766de7792SLi Zefan } else { 11282db270a8SFrederic Weisbecker if (t_sec(ent)) 11292db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu + %u [%s]\n", 11302db270a8SFrederic Weisbecker t_sector(ent), t_sec(ent), cmd); 11312db270a8SFrederic Weisbecker return trace_seq_printf(s, "[%s]\n", cmd); 11322db270a8SFrederic Weisbecker } 113366de7792SLi Zefan } 11342db270a8SFrederic Weisbecker 11352db270a8SFrederic Weisbecker static int blk_log_with_error(struct trace_seq *s, 11362db270a8SFrederic Weisbecker const struct trace_entry *ent) 11372db270a8SFrederic Weisbecker { 113866de7792SLi Zefan if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { 113966de7792SLi Zefan int ret; 114066de7792SLi Zefan 114166de7792SLi Zefan ret = blk_log_dump_pdu(s, ent); 114266de7792SLi Zefan if (ret) 114366de7792SLi Zefan return trace_seq_printf(s, "[%d]\n", t_error(ent)); 114466de7792SLi Zefan return 0; 114566de7792SLi Zefan } else { 11462db270a8SFrederic Weisbecker if (t_sec(ent)) 114766de7792SLi Zefan return trace_seq_printf(s, "%llu + %u [%d]\n", 114866de7792SLi Zefan t_sector(ent), 11492db270a8SFrederic Weisbecker t_sec(ent), t_error(ent)); 115066de7792SLi Zefan return trace_seq_printf(s, "%llu [%d]\n", 115166de7792SLi Zefan t_sector(ent), t_error(ent)); 115266de7792SLi Zefan } 11532db270a8SFrederic Weisbecker } 11542db270a8SFrederic Weisbecker 11552db270a8SFrederic Weisbecker static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) 11562db270a8SFrederic Weisbecker { 1157a42aaa3bSAlan D. Brunelle struct blk_io_trace_remap r = { .device_from = 0, }; 11582db270a8SFrederic Weisbecker 11592db270a8SFrederic Weisbecker get_pdu_remap(ent, &r); 11602db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", 1161a42aaa3bSAlan D. Brunelle t_sector(ent), t_sec(ent), 1162a42aaa3bSAlan D. Brunelle MAJOR(r.device_from), MINOR(r.device_from), 1163a42aaa3bSAlan D. Brunelle (unsigned long long)r.sector_from); 11642db270a8SFrederic Weisbecker } 11652db270a8SFrederic Weisbecker 11662db270a8SFrederic Weisbecker static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) 11672db270a8SFrederic Weisbecker { 11684ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 11694ca53085SSteven Rostedt 11704ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 11714ca53085SSteven Rostedt 11724ca53085SSteven Rostedt return trace_seq_printf(s, "[%s]\n", cmd); 11732db270a8SFrederic Weisbecker } 11742db270a8SFrederic Weisbecker 11752db270a8SFrederic Weisbecker static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) 11762db270a8SFrederic Weisbecker { 11774ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 11784ca53085SSteven Rostedt 11794ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 11804ca53085SSteven Rostedt 11814ca53085SSteven Rostedt return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); 11822db270a8SFrederic Weisbecker } 11832db270a8SFrederic Weisbecker 11842db270a8SFrederic Weisbecker static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) 11852db270a8SFrederic Weisbecker { 11864ca53085SSteven Rostedt char cmd[TASK_COMM_LEN]; 11874ca53085SSteven Rostedt 11884ca53085SSteven Rostedt trace_find_cmdline(ent->pid, cmd); 11894ca53085SSteven Rostedt 11902db270a8SFrederic Weisbecker return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), 11914ca53085SSteven Rostedt get_pdu_int(ent), cmd); 11922db270a8SFrederic Weisbecker } 11932db270a8SFrederic Weisbecker 119418cea459SLi Zefan static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent) 119518cea459SLi Zefan { 119618cea459SLi Zefan int ret; 119718cea459SLi Zefan const struct blk_io_trace *t = te_blk_io_trace(ent); 119818cea459SLi Zefan 119918cea459SLi Zefan ret = trace_seq_putmem(s, t + 1, t->pdu_len); 120018cea459SLi Zefan if (ret) 120118cea459SLi Zefan return trace_seq_putc(s, '\n'); 120218cea459SLi Zefan return ret; 120318cea459SLi Zefan } 120418cea459SLi Zefan 12052db270a8SFrederic Weisbecker /* 12062db270a8SFrederic Weisbecker * struct tracer operations 12072db270a8SFrederic Weisbecker */ 12082db270a8SFrederic Weisbecker 12092db270a8SFrederic Weisbecker static void blk_tracer_print_header(struct seq_file *m) 12102db270a8SFrederic Weisbecker { 12112db270a8SFrederic Weisbecker if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) 12122db270a8SFrederic Weisbecker return; 12132db270a8SFrederic Weisbecker seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" 12142db270a8SFrederic Weisbecker "# | | | | | |\n"); 12152db270a8SFrederic Weisbecker } 12162db270a8SFrederic Weisbecker 12172db270a8SFrederic Weisbecker static void blk_tracer_start(struct trace_array *tr) 12182db270a8SFrederic Weisbecker { 1219ad5dd549SLi Zefan blk_tracer_enabled = true; 12202db270a8SFrederic Weisbecker } 12212db270a8SFrederic Weisbecker 12222db270a8SFrederic Weisbecker static int blk_tracer_init(struct trace_array *tr) 12232db270a8SFrederic Weisbecker { 12242db270a8SFrederic Weisbecker blk_tr = tr; 12252db270a8SFrederic Weisbecker blk_tracer_start(tr); 12262db270a8SFrederic Weisbecker return 0; 12272db270a8SFrederic Weisbecker } 12282db270a8SFrederic Weisbecker 12292db270a8SFrederic Weisbecker static void blk_tracer_stop(struct trace_array *tr) 12302db270a8SFrederic Weisbecker { 1231ad5dd549SLi Zefan blk_tracer_enabled = false; 12322db270a8SFrederic Weisbecker } 12332db270a8SFrederic Weisbecker 12342db270a8SFrederic Weisbecker static void blk_tracer_reset(struct trace_array *tr) 12352db270a8SFrederic Weisbecker { 12362db270a8SFrederic Weisbecker blk_tracer_stop(tr); 12372db270a8SFrederic Weisbecker } 12382db270a8SFrederic Weisbecker 1239e4955c99SLi Zefan static const struct { 12402db270a8SFrederic Weisbecker const char *act[2]; 12412db270a8SFrederic Weisbecker int (*print)(struct trace_seq *s, const struct trace_entry *ent); 1242e4955c99SLi Zefan } what2act[] = { 12432db270a8SFrederic Weisbecker [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, 12442db270a8SFrederic Weisbecker [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, 12452db270a8SFrederic Weisbecker [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, 12462db270a8SFrederic Weisbecker [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, 12472db270a8SFrederic Weisbecker [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, 12482db270a8SFrederic Weisbecker [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, 12492db270a8SFrederic Weisbecker [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, 12502db270a8SFrederic Weisbecker [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, 12512db270a8SFrederic Weisbecker [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, 12522db270a8SFrederic Weisbecker [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, 12532db270a8SFrederic Weisbecker [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, 12542db270a8SFrederic Weisbecker [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, 12552db270a8SFrederic Weisbecker [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, 12562db270a8SFrederic Weisbecker [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, 12572db270a8SFrederic Weisbecker [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, 12582db270a8SFrederic Weisbecker }; 12592db270a8SFrederic Weisbecker 1260b6a4b0c3SLi Zefan static enum print_line_t print_one_line(struct trace_iterator *iter, 1261b6a4b0c3SLi Zefan bool classic) 12622db270a8SFrederic Weisbecker { 12632db270a8SFrederic Weisbecker struct trace_seq *s = &iter->seq; 1264b6a4b0c3SLi Zefan const struct blk_io_trace *t; 1265b6a4b0c3SLi Zefan u16 what; 12662db270a8SFrederic Weisbecker int ret; 1267b6a4b0c3SLi Zefan bool long_act; 1268b6a4b0c3SLi Zefan blk_log_action_t *log_action; 12692db270a8SFrederic Weisbecker 1270b6a4b0c3SLi Zefan t = te_blk_io_trace(iter->ent); 1271b6a4b0c3SLi Zefan what = t->action & ((1 << BLK_TC_SHIFT) - 1); 1272b6a4b0c3SLi Zefan long_act = !!(trace_flags & TRACE_ITER_VERBOSE); 1273b6a4b0c3SLi Zefan log_action = classic ? &blk_log_action_classic : &blk_log_action; 12742db270a8SFrederic Weisbecker 127518cea459SLi Zefan if (t->action == BLK_TN_MESSAGE) { 127618cea459SLi Zefan ret = log_action(iter, long_act ? "message" : "m"); 127718cea459SLi Zefan if (ret) 127818cea459SLi Zefan ret = blk_log_msg(s, iter->ent); 127918cea459SLi Zefan goto out; 128018cea459SLi Zefan } 128118cea459SLi Zefan 1282eb08f8ebSLi Zefan if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) 1283b78825d6SLi Zefan ret = trace_seq_printf(s, "Unknown action %x\n", what); 12842db270a8SFrederic Weisbecker else { 1285b6a4b0c3SLi Zefan ret = log_action(iter, what2act[what].act[long_act]); 12862db270a8SFrederic Weisbecker if (ret) 12872db270a8SFrederic Weisbecker ret = what2act[what].print(s, iter->ent); 12882db270a8SFrederic Weisbecker } 128918cea459SLi Zefan out: 12902db270a8SFrederic Weisbecker return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; 12912db270a8SFrederic Weisbecker } 12922db270a8SFrederic Weisbecker 1293b6a4b0c3SLi Zefan static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, 1294b6a4b0c3SLi Zefan int flags) 1295b6a4b0c3SLi Zefan { 1296b6a4b0c3SLi Zefan return print_one_line(iter, false); 1297b6a4b0c3SLi Zefan } 1298b6a4b0c3SLi Zefan 12992db270a8SFrederic Weisbecker static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) 13002db270a8SFrederic Weisbecker { 13012db270a8SFrederic Weisbecker struct trace_seq *s = &iter->seq; 13022db270a8SFrederic Weisbecker struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; 13032db270a8SFrederic Weisbecker const int offset = offsetof(struct blk_io_trace, sector); 13042db270a8SFrederic Weisbecker struct blk_io_trace old = { 13052db270a8SFrederic Weisbecker .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, 13066c051ce0SLi Zefan .time = iter->ts, 13072db270a8SFrederic Weisbecker }; 13082db270a8SFrederic Weisbecker 13092db270a8SFrederic Weisbecker if (!trace_seq_putmem(s, &old, offset)) 13102db270a8SFrederic Weisbecker return 0; 13112db270a8SFrederic Weisbecker return trace_seq_putmem(s, &t->sector, 13122db270a8SFrederic Weisbecker sizeof(old) - offset + t->pdu_len); 13132db270a8SFrederic Weisbecker } 13142db270a8SFrederic Weisbecker 13152db270a8SFrederic Weisbecker static enum print_line_t 13162db270a8SFrederic Weisbecker blk_trace_event_print_binary(struct trace_iterator *iter, int flags) 13172db270a8SFrederic Weisbecker { 13182db270a8SFrederic Weisbecker return blk_trace_synthesize_old_trace(iter) ? 13192db270a8SFrederic Weisbecker TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; 13202db270a8SFrederic Weisbecker } 13212db270a8SFrederic Weisbecker 13222db270a8SFrederic Weisbecker static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) 13232db270a8SFrederic Weisbecker { 13242db270a8SFrederic Weisbecker if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) 13252db270a8SFrederic Weisbecker return TRACE_TYPE_UNHANDLED; 13262db270a8SFrederic Weisbecker 1327b6a4b0c3SLi Zefan return print_one_line(iter, true); 13282db270a8SFrederic Weisbecker } 13292db270a8SFrederic Weisbecker 1330f3948f88SLi Zefan static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) 1331f3948f88SLi Zefan { 1332f3948f88SLi Zefan /* don't output context-info for blk_classic output */ 1333f3948f88SLi Zefan if (bit == TRACE_BLK_OPT_CLASSIC) { 1334f3948f88SLi Zefan if (set) 1335f3948f88SLi Zefan trace_flags &= ~TRACE_ITER_CONTEXT_INFO; 1336f3948f88SLi Zefan else 1337f3948f88SLi Zefan trace_flags |= TRACE_ITER_CONTEXT_INFO; 1338f3948f88SLi Zefan } 1339f3948f88SLi Zefan return 0; 1340f3948f88SLi Zefan } 1341f3948f88SLi Zefan 13422db270a8SFrederic Weisbecker static struct tracer blk_tracer __read_mostly = { 13432db270a8SFrederic Weisbecker .name = "blk", 13442db270a8SFrederic Weisbecker .init = blk_tracer_init, 13452db270a8SFrederic Weisbecker .reset = blk_tracer_reset, 13462db270a8SFrederic Weisbecker .start = blk_tracer_start, 13472db270a8SFrederic Weisbecker .stop = blk_tracer_stop, 13482db270a8SFrederic Weisbecker .print_header = blk_tracer_print_header, 13492db270a8SFrederic Weisbecker .print_line = blk_tracer_print_line, 13502db270a8SFrederic Weisbecker .flags = &blk_tracer_flags, 1351f3948f88SLi Zefan .set_flag = blk_tracer_set_flag, 13522db270a8SFrederic Weisbecker }; 13532db270a8SFrederic Weisbecker 13542db270a8SFrederic Weisbecker static struct trace_event trace_blk_event = { 13552db270a8SFrederic Weisbecker .type = TRACE_BLK, 13562db270a8SFrederic Weisbecker .trace = blk_trace_event_print, 13572db270a8SFrederic Weisbecker .binary = blk_trace_event_print_binary, 13582db270a8SFrederic Weisbecker }; 13592db270a8SFrederic Weisbecker 13602db270a8SFrederic Weisbecker static int __init init_blk_tracer(void) 13612db270a8SFrederic Weisbecker { 13622db270a8SFrederic Weisbecker if (!register_ftrace_event(&trace_blk_event)) { 13632db270a8SFrederic Weisbecker pr_warning("Warning: could not register block events\n"); 13642db270a8SFrederic Weisbecker return 1; 13652db270a8SFrederic Weisbecker } 13662db270a8SFrederic Weisbecker 13672db270a8SFrederic Weisbecker if (register_tracer(&blk_tracer) != 0) { 13682db270a8SFrederic Weisbecker pr_warning("Warning: could not register the block tracer\n"); 13692db270a8SFrederic Weisbecker unregister_ftrace_event(&trace_blk_event); 13702db270a8SFrederic Weisbecker return 1; 13712db270a8SFrederic Weisbecker } 13722db270a8SFrederic Weisbecker 13732db270a8SFrederic Weisbecker return 0; 13742db270a8SFrederic Weisbecker } 13752db270a8SFrederic Weisbecker 13762db270a8SFrederic Weisbecker device_initcall(init_blk_tracer); 13772db270a8SFrederic Weisbecker 13782db270a8SFrederic Weisbecker static int blk_trace_remove_queue(struct request_queue *q) 13792db270a8SFrederic Weisbecker { 13802db270a8SFrederic Weisbecker struct blk_trace *bt; 13812db270a8SFrederic Weisbecker 13822db270a8SFrederic Weisbecker bt = xchg(&q->blk_trace, NULL); 13832db270a8SFrederic Weisbecker if (bt == NULL) 13842db270a8SFrederic Weisbecker return -EINVAL; 13852db270a8SFrederic Weisbecker 138617ba97e3SLi Zefan if (atomic_dec_and_test(&blk_probes_ref)) 138717ba97e3SLi Zefan blk_unregister_tracepoints(); 138817ba97e3SLi Zefan 1389ad5dd549SLi Zefan blk_trace_free(bt); 13902db270a8SFrederic Weisbecker return 0; 13912db270a8SFrederic Weisbecker } 13922db270a8SFrederic Weisbecker 13932db270a8SFrederic Weisbecker /* 13942db270a8SFrederic Weisbecker * Setup everything required to start tracing 13952db270a8SFrederic Weisbecker */ 13969908c309SLi Zefan static int blk_trace_setup_queue(struct request_queue *q, 13979908c309SLi Zefan struct block_device *bdev) 13982db270a8SFrederic Weisbecker { 13992db270a8SFrederic Weisbecker struct blk_trace *old_bt, *bt = NULL; 140018cea459SLi Zefan int ret = -ENOMEM; 14012db270a8SFrederic Weisbecker 14022db270a8SFrederic Weisbecker bt = kzalloc(sizeof(*bt), GFP_KERNEL); 14032db270a8SFrederic Weisbecker if (!bt) 140415152e44SLi Zefan return -ENOMEM; 14052db270a8SFrederic Weisbecker 140618cea459SLi Zefan bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); 140718cea459SLi Zefan if (!bt->msg_data) 140818cea459SLi Zefan goto free_bt; 140918cea459SLi Zefan 14109908c309SLi Zefan bt->dev = bdev->bd_dev; 14112db270a8SFrederic Weisbecker bt->act_mask = (u16)-1; 14129908c309SLi Zefan 14139908c309SLi Zefan blk_trace_setup_lba(bt, bdev); 14142db270a8SFrederic Weisbecker 14152db270a8SFrederic Weisbecker old_bt = xchg(&q->blk_trace, bt); 14162db270a8SFrederic Weisbecker if (old_bt != NULL) { 14172db270a8SFrederic Weisbecker (void)xchg(&q->blk_trace, old_bt); 141818cea459SLi Zefan ret = -EBUSY; 141918cea459SLi Zefan goto free_bt; 14202db270a8SFrederic Weisbecker } 142115152e44SLi Zefan 142217ba97e3SLi Zefan if (atomic_inc_return(&blk_probes_ref) == 1) 142317ba97e3SLi Zefan blk_register_tracepoints(); 14242db270a8SFrederic Weisbecker return 0; 142518cea459SLi Zefan 142618cea459SLi Zefan free_bt: 142718cea459SLi Zefan blk_trace_free(bt); 142818cea459SLi Zefan return ret; 14292db270a8SFrederic Weisbecker } 14302db270a8SFrederic Weisbecker 14312db270a8SFrederic Weisbecker /* 14322db270a8SFrederic Weisbecker * sysfs interface to enable and configure tracing 14332db270a8SFrederic Weisbecker */ 14342db270a8SFrederic Weisbecker 14352db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_show(struct device *dev, 14362db270a8SFrederic Weisbecker struct device_attribute *attr, 14372db270a8SFrederic Weisbecker char *buf); 14382db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_store(struct device *dev, 14392db270a8SFrederic Weisbecker struct device_attribute *attr, 14402db270a8SFrederic Weisbecker const char *buf, size_t count); 14412db270a8SFrederic Weisbecker #define BLK_TRACE_DEVICE_ATTR(_name) \ 14422db270a8SFrederic Weisbecker DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ 14432db270a8SFrederic Weisbecker sysfs_blk_trace_attr_show, \ 14442db270a8SFrederic Weisbecker sysfs_blk_trace_attr_store) 14452db270a8SFrederic Weisbecker 1446cd649b8bSLi Zefan static BLK_TRACE_DEVICE_ATTR(enable); 14472db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(act_mask); 14482db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(pid); 14492db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(start_lba); 14502db270a8SFrederic Weisbecker static BLK_TRACE_DEVICE_ATTR(end_lba); 14512db270a8SFrederic Weisbecker 14522db270a8SFrederic Weisbecker static struct attribute *blk_trace_attrs[] = { 14532db270a8SFrederic Weisbecker &dev_attr_enable.attr, 14542db270a8SFrederic Weisbecker &dev_attr_act_mask.attr, 14552db270a8SFrederic Weisbecker &dev_attr_pid.attr, 14562db270a8SFrederic Weisbecker &dev_attr_start_lba.attr, 14572db270a8SFrederic Weisbecker &dev_attr_end_lba.attr, 14582db270a8SFrederic Weisbecker NULL 14592db270a8SFrederic Weisbecker }; 14602db270a8SFrederic Weisbecker 14612db270a8SFrederic Weisbecker struct attribute_group blk_trace_attr_group = { 14622db270a8SFrederic Weisbecker .name = "trace", 14632db270a8SFrederic Weisbecker .attrs = blk_trace_attrs, 14642db270a8SFrederic Weisbecker }; 14652db270a8SFrederic Weisbecker 146609341997SLi Zefan static const struct { 146709341997SLi Zefan int mask; 146809341997SLi Zefan const char *str; 146909341997SLi Zefan } mask_maps[] = { 147009341997SLi Zefan { BLK_TC_READ, "read" }, 147109341997SLi Zefan { BLK_TC_WRITE, "write" }, 147209341997SLi Zefan { BLK_TC_BARRIER, "barrier" }, 147309341997SLi Zefan { BLK_TC_SYNC, "sync" }, 147409341997SLi Zefan { BLK_TC_QUEUE, "queue" }, 147509341997SLi Zefan { BLK_TC_REQUEUE, "requeue" }, 147609341997SLi Zefan { BLK_TC_ISSUE, "issue" }, 147709341997SLi Zefan { BLK_TC_COMPLETE, "complete" }, 147809341997SLi Zefan { BLK_TC_FS, "fs" }, 147909341997SLi Zefan { BLK_TC_PC, "pc" }, 148009341997SLi Zefan { BLK_TC_AHEAD, "ahead" }, 148109341997SLi Zefan { BLK_TC_META, "meta" }, 148209341997SLi Zefan { BLK_TC_DISCARD, "discard" }, 148309341997SLi Zefan { BLK_TC_DRV_DATA, "drv_data" }, 148409341997SLi Zefan }; 148509341997SLi Zefan 148609341997SLi Zefan static int blk_trace_str2mask(const char *str) 14872db270a8SFrederic Weisbecker { 148809341997SLi Zefan int i; 14892db270a8SFrederic Weisbecker int mask = 0; 14909eb85125SLi Zefan char *buf, *s, *token; 14912db270a8SFrederic Weisbecker 14929eb85125SLi Zefan buf = kstrdup(str, GFP_KERNEL); 14939eb85125SLi Zefan if (buf == NULL) 14942db270a8SFrederic Weisbecker return -ENOMEM; 14959eb85125SLi Zefan s = strstrip(buf); 14962db270a8SFrederic Weisbecker 14972db270a8SFrederic Weisbecker while (1) { 149809341997SLi Zefan token = strsep(&s, ","); 149909341997SLi Zefan if (token == NULL) 15002db270a8SFrederic Weisbecker break; 15012db270a8SFrederic Weisbecker 150209341997SLi Zefan if (*token == '\0') 150309341997SLi Zefan continue; 150409341997SLi Zefan 150509341997SLi Zefan for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { 150609341997SLi Zefan if (strcasecmp(token, mask_maps[i].str) == 0) { 150709341997SLi Zefan mask |= mask_maps[i].mask; 150809341997SLi Zefan break; 15092db270a8SFrederic Weisbecker } 151009341997SLi Zefan } 151109341997SLi Zefan if (i == ARRAY_SIZE(mask_maps)) { 151209341997SLi Zefan mask = -EINVAL; 151309341997SLi Zefan break; 151409341997SLi Zefan } 151509341997SLi Zefan } 15169eb85125SLi Zefan kfree(buf); 15172db270a8SFrederic Weisbecker 15182db270a8SFrederic Weisbecker return mask; 15192db270a8SFrederic Weisbecker } 15202db270a8SFrederic Weisbecker 152109341997SLi Zefan static ssize_t blk_trace_mask2str(char *buf, int mask) 152209341997SLi Zefan { 152309341997SLi Zefan int i; 152409341997SLi Zefan char *p = buf; 152509341997SLi Zefan 152609341997SLi Zefan for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { 152709341997SLi Zefan if (mask & mask_maps[i].mask) { 152809341997SLi Zefan p += sprintf(p, "%s%s", 152909341997SLi Zefan (p == buf) ? "" : ",", mask_maps[i].str); 153009341997SLi Zefan } 153109341997SLi Zefan } 153209341997SLi Zefan *p++ = '\n'; 153309341997SLi Zefan 153409341997SLi Zefan return p - buf; 153509341997SLi Zefan } 153609341997SLi Zefan 1537b125130bSLi Zefan static struct request_queue *blk_trace_get_queue(struct block_device *bdev) 1538b125130bSLi Zefan { 1539b125130bSLi Zefan if (bdev->bd_disk == NULL) 1540b125130bSLi Zefan return NULL; 1541b125130bSLi Zefan 1542b125130bSLi Zefan return bdev_get_queue(bdev); 1543b125130bSLi Zefan } 1544b125130bSLi Zefan 15452db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_show(struct device *dev, 15462db270a8SFrederic Weisbecker struct device_attribute *attr, 15472db270a8SFrederic Weisbecker char *buf) 15482db270a8SFrederic Weisbecker { 15492db270a8SFrederic Weisbecker struct hd_struct *p = dev_to_part(dev); 15502db270a8SFrederic Weisbecker struct request_queue *q; 15512db270a8SFrederic Weisbecker struct block_device *bdev; 15522db270a8SFrederic Weisbecker ssize_t ret = -ENXIO; 15532db270a8SFrederic Weisbecker 15542db270a8SFrederic Weisbecker lock_kernel(); 15552db270a8SFrederic Weisbecker bdev = bdget(part_devt(p)); 15562db270a8SFrederic Weisbecker if (bdev == NULL) 15572db270a8SFrederic Weisbecker goto out_unlock_kernel; 15582db270a8SFrederic Weisbecker 1559b125130bSLi Zefan q = blk_trace_get_queue(bdev); 15602db270a8SFrederic Weisbecker if (q == NULL) 15612db270a8SFrederic Weisbecker goto out_bdput; 1562b125130bSLi Zefan 15632db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 1564cd649b8bSLi Zefan 1565cd649b8bSLi Zefan if (attr == &dev_attr_enable) { 1566cd649b8bSLi Zefan ret = sprintf(buf, "%u\n", !!q->blk_trace); 1567cd649b8bSLi Zefan goto out_unlock_bdev; 1568cd649b8bSLi Zefan } 1569cd649b8bSLi Zefan 15702db270a8SFrederic Weisbecker if (q->blk_trace == NULL) 15712db270a8SFrederic Weisbecker ret = sprintf(buf, "disabled\n"); 15722db270a8SFrederic Weisbecker else if (attr == &dev_attr_act_mask) 157309341997SLi Zefan ret = blk_trace_mask2str(buf, q->blk_trace->act_mask); 15742db270a8SFrederic Weisbecker else if (attr == &dev_attr_pid) 15752db270a8SFrederic Weisbecker ret = sprintf(buf, "%u\n", q->blk_trace->pid); 15762db270a8SFrederic Weisbecker else if (attr == &dev_attr_start_lba) 15772db270a8SFrederic Weisbecker ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); 15782db270a8SFrederic Weisbecker else if (attr == &dev_attr_end_lba) 15792db270a8SFrederic Weisbecker ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); 1580cd649b8bSLi Zefan 1581cd649b8bSLi Zefan out_unlock_bdev: 15822db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 15832db270a8SFrederic Weisbecker out_bdput: 15842db270a8SFrederic Weisbecker bdput(bdev); 15852db270a8SFrederic Weisbecker out_unlock_kernel: 15862db270a8SFrederic Weisbecker unlock_kernel(); 15872db270a8SFrederic Weisbecker return ret; 15882db270a8SFrederic Weisbecker } 15892db270a8SFrederic Weisbecker 15902db270a8SFrederic Weisbecker static ssize_t sysfs_blk_trace_attr_store(struct device *dev, 15912db270a8SFrederic Weisbecker struct device_attribute *attr, 15922db270a8SFrederic Weisbecker const char *buf, size_t count) 15932db270a8SFrederic Weisbecker { 15942db270a8SFrederic Weisbecker struct block_device *bdev; 15952db270a8SFrederic Weisbecker struct request_queue *q; 15962db270a8SFrederic Weisbecker struct hd_struct *p; 15972db270a8SFrederic Weisbecker u64 value; 159809341997SLi Zefan ssize_t ret = -EINVAL; 15992db270a8SFrederic Weisbecker 16002db270a8SFrederic Weisbecker if (count == 0) 16012db270a8SFrederic Weisbecker goto out; 16022db270a8SFrederic Weisbecker 16032db270a8SFrederic Weisbecker if (attr == &dev_attr_act_mask) { 16042db270a8SFrederic Weisbecker if (sscanf(buf, "%llx", &value) != 1) { 16052db270a8SFrederic Weisbecker /* Assume it is a list of trace category names */ 160609341997SLi Zefan ret = blk_trace_str2mask(buf); 160709341997SLi Zefan if (ret < 0) 16082db270a8SFrederic Weisbecker goto out; 160909341997SLi Zefan value = ret; 16102db270a8SFrederic Weisbecker } 16112db270a8SFrederic Weisbecker } else if (sscanf(buf, "%llu", &value) != 1) 16122db270a8SFrederic Weisbecker goto out; 16132db270a8SFrederic Weisbecker 161409341997SLi Zefan ret = -ENXIO; 161509341997SLi Zefan 16162db270a8SFrederic Weisbecker lock_kernel(); 16172db270a8SFrederic Weisbecker p = dev_to_part(dev); 16182db270a8SFrederic Weisbecker bdev = bdget(part_devt(p)); 16192db270a8SFrederic Weisbecker if (bdev == NULL) 16202db270a8SFrederic Weisbecker goto out_unlock_kernel; 16212db270a8SFrederic Weisbecker 1622b125130bSLi Zefan q = blk_trace_get_queue(bdev); 16232db270a8SFrederic Weisbecker if (q == NULL) 16242db270a8SFrederic Weisbecker goto out_bdput; 16252db270a8SFrederic Weisbecker 16262db270a8SFrederic Weisbecker mutex_lock(&bdev->bd_mutex); 1627cd649b8bSLi Zefan 1628cd649b8bSLi Zefan if (attr == &dev_attr_enable) { 1629cd649b8bSLi Zefan if (value) 16309908c309SLi Zefan ret = blk_trace_setup_queue(q, bdev); 1631cd649b8bSLi Zefan else 1632cd649b8bSLi Zefan ret = blk_trace_remove_queue(q); 1633cd649b8bSLi Zefan goto out_unlock_bdev; 1634cd649b8bSLi Zefan } 1635cd649b8bSLi Zefan 16362db270a8SFrederic Weisbecker ret = 0; 16372db270a8SFrederic Weisbecker if (q->blk_trace == NULL) 16389908c309SLi Zefan ret = blk_trace_setup_queue(q, bdev); 16392db270a8SFrederic Weisbecker 16402db270a8SFrederic Weisbecker if (ret == 0) { 16412db270a8SFrederic Weisbecker if (attr == &dev_attr_act_mask) 16422db270a8SFrederic Weisbecker q->blk_trace->act_mask = value; 16432db270a8SFrederic Weisbecker else if (attr == &dev_attr_pid) 16442db270a8SFrederic Weisbecker q->blk_trace->pid = value; 16452db270a8SFrederic Weisbecker else if (attr == &dev_attr_start_lba) 16462db270a8SFrederic Weisbecker q->blk_trace->start_lba = value; 16472db270a8SFrederic Weisbecker else if (attr == &dev_attr_end_lba) 16482db270a8SFrederic Weisbecker q->blk_trace->end_lba = value; 16492db270a8SFrederic Weisbecker } 1650cd649b8bSLi Zefan 1651cd649b8bSLi Zefan out_unlock_bdev: 16522db270a8SFrederic Weisbecker mutex_unlock(&bdev->bd_mutex); 16532db270a8SFrederic Weisbecker out_bdput: 16542db270a8SFrederic Weisbecker bdput(bdev); 16552db270a8SFrederic Weisbecker out_unlock_kernel: 16562db270a8SFrederic Weisbecker unlock_kernel(); 16572db270a8SFrederic Weisbecker out: 1658cd649b8bSLi Zefan return ret ? ret : count; 16592db270a8SFrederic Weisbecker } 1660cd649b8bSLi Zefan 16611d54ad6dSLi Zefan int blk_trace_init_sysfs(struct device *dev) 16621d54ad6dSLi Zefan { 16631d54ad6dSLi Zefan return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); 16641d54ad6dSLi Zefan } 16651d54ad6dSLi Zefan 166655782138SLi Zefan #endif /* CONFIG_BLK_DEV_IO_TRACE */ 166755782138SLi Zefan 166855782138SLi Zefan #ifdef CONFIG_EVENT_TRACING 166955782138SLi Zefan 167055782138SLi Zefan void blk_dump_cmd(char *buf, struct request *rq) 167155782138SLi Zefan { 167255782138SLi Zefan int i, end; 167355782138SLi Zefan int len = rq->cmd_len; 167455782138SLi Zefan unsigned char *cmd = rq->cmd; 167555782138SLi Zefan 167655782138SLi Zefan if (!blk_pc_request(rq)) { 167755782138SLi Zefan buf[0] = '\0'; 167855782138SLi Zefan return; 167955782138SLi Zefan } 168055782138SLi Zefan 168155782138SLi Zefan for (end = len - 1; end >= 0; end--) 168255782138SLi Zefan if (cmd[end]) 168355782138SLi Zefan break; 168455782138SLi Zefan end++; 168555782138SLi Zefan 168655782138SLi Zefan for (i = 0; i < len; i++) { 168755782138SLi Zefan buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]); 168855782138SLi Zefan if (i == end && end != len - 1) { 168955782138SLi Zefan sprintf(buf, " .."); 169055782138SLi Zefan break; 169155782138SLi Zefan } 169255782138SLi Zefan } 169355782138SLi Zefan } 169455782138SLi Zefan 169555782138SLi Zefan void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) 169655782138SLi Zefan { 169755782138SLi Zefan int i = 0; 169855782138SLi Zefan 169955782138SLi Zefan if (rw & WRITE) 170055782138SLi Zefan rwbs[i++] = 'W'; 170155782138SLi Zefan else if (rw & 1 << BIO_RW_DISCARD) 170255782138SLi Zefan rwbs[i++] = 'D'; 170355782138SLi Zefan else if (bytes) 170455782138SLi Zefan rwbs[i++] = 'R'; 170555782138SLi Zefan else 170655782138SLi Zefan rwbs[i++] = 'N'; 170755782138SLi Zefan 170855782138SLi Zefan if (rw & 1 << BIO_RW_AHEAD) 170955782138SLi Zefan rwbs[i++] = 'A'; 171055782138SLi Zefan if (rw & 1 << BIO_RW_BARRIER) 171155782138SLi Zefan rwbs[i++] = 'B'; 171255782138SLi Zefan if (rw & 1 << BIO_RW_SYNCIO) 171355782138SLi Zefan rwbs[i++] = 'S'; 171455782138SLi Zefan if (rw & 1 << BIO_RW_META) 171555782138SLi Zefan rwbs[i++] = 'M'; 171655782138SLi Zefan 171755782138SLi Zefan rwbs[i] = '\0'; 171855782138SLi Zefan } 171955782138SLi Zefan 172055782138SLi Zefan void blk_fill_rwbs_rq(char *rwbs, struct request *rq) 172155782138SLi Zefan { 172255782138SLi Zefan int rw = rq->cmd_flags & 0x03; 172355782138SLi Zefan int bytes; 172455782138SLi Zefan 172555782138SLi Zefan if (blk_discard_rq(rq)) 172655782138SLi Zefan rw |= (1 << BIO_RW_DISCARD); 172755782138SLi Zefan 1728c9059598SLinus Torvalds bytes = blk_rq_bytes(rq); 172955782138SLi Zefan 173055782138SLi Zefan blk_fill_rwbs(rwbs, rw, bytes); 173155782138SLi Zefan } 173255782138SLi Zefan 173355782138SLi Zefan #endif /* CONFIG_EVENT_TRACING */ 173455782138SLi Zefan 1735