Remove double removal of blktrace directory
[safe/jmp/linux-2.6] / kernel / trace / blktrace.c
index 5708a14..7a34cb5 100644 (file)
 #include <linux/init.h>
 #include <linux/mutex.h>
 #include <linux/debugfs.h>
+#include <linux/smp_lock.h>
 #include <linux/time.h>
-#include <trace/block.h>
 #include <linux/uaccess.h>
+
+#include <trace/events/block.h>
+
 #include "trace_output.h"
 
+#ifdef CONFIG_BLK_DEV_IO_TRACE
+
 static unsigned int blktrace_seq __read_mostly = 1;
 
 static struct trace_array *blk_tr;
@@ -147,7 +152,7 @@ static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector,
 {
        if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0)
                return 1;
-       if (sector < bt->start_lba || sector > bt->end_lba)
+       if (sector && (sector < bt->start_lba || sector > bt->end_lba))
                return 1;
        if (bt->pid && pid != bt->pid)
                return 1;
@@ -192,7 +197,7 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
        what |= MASK_TC_BIT(rw, DISCARD);
 
        pid = tsk->pid;
-       if (unlikely(act_log_check(bt, what, sector, pid)))
+       if (act_log_check(bt, what, sector, pid))
                return;
        cpu = raw_smp_processor_id();
 
@@ -263,6 +268,7 @@ static void blk_trace_free(struct blk_trace *bt)
        debugfs_remove(bt->msg_file);
        debugfs_remove(bt->dropped_file);
        relay_close(bt->rchan);
+       debugfs_remove(bt->dir);
        free_percpu(bt->sequence);
        free_percpu(bt->msg_data);
        kfree(bt);
@@ -372,18 +378,8 @@ static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf,
 
 static int blk_remove_buf_file_callback(struct dentry *dentry)
 {
-       struct dentry *parent = dentry->d_parent;
        debugfs_remove(dentry);
 
-       /*
-       * this will fail for all but the last file, but that is ok. what we
-       * care about is the top level buts->name directory going away, when
-       * the last trace file is gone. Then we don't have to rmdir() that
-       * manually on trace stop, so it nicely solves the issue with
-       * force killing of running traces.
-       */
-
-       debugfs_remove(parent);
        return 0;
 }
 
@@ -403,11 +399,29 @@ static struct rchan_callbacks blk_relay_callbacks = {
        .remove_buf_file        = blk_remove_buf_file_callback,
 };
 
+static void blk_trace_setup_lba(struct blk_trace *bt,
+                               struct block_device *bdev)
+{
+       struct hd_struct *part = NULL;
+
+       if (bdev)
+               part = bdev->bd_part;
+
+       if (part) {
+               bt->start_lba = part->start_sect;
+               bt->end_lba = part->start_sect + part->nr_sects;
+       } else {
+               bt->start_lba = 0;
+               bt->end_lba = -1ULL;
+       }
+}
+
 /*
  * Setup everything required to start tracing
  */
 int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
-                       struct blk_user_trace_setup *buts)
+                      struct block_device *bdev,
+                      struct blk_user_trace_setup *buts)
 {
        struct blk_trace *old_bt, *bt = NULL;
        struct dentry *dir = NULL;
@@ -480,10 +494,13 @@ int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
        if (!bt->act_mask)
                bt->act_mask = (u16) -1;
 
-       bt->start_lba = buts->start_lba;
-       bt->end_lba = buts->end_lba;
-       if (!bt->end_lba)
-               bt->end_lba = -1ULL;
+       blk_trace_setup_lba(bt, bdev);
+
+       /* overwrite with user settings */
+       if (buts->start_lba)
+               bt->start_lba = buts->start_lba;
+       if (buts->end_lba)
+               bt->end_lba = buts->end_lba;
 
        bt->pid = buts->pid;
        bt->trace_state = Blktrace_setup;
@@ -505,6 +522,7 @@ err:
 }
 
 int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
+                   struct block_device *bdev,
                    char __user *arg)
 {
        struct blk_user_trace_setup buts;
@@ -514,7 +532,7 @@ int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
        if (ret)
                return -EFAULT;
 
-       ret = do_blk_trace_setup(q, name, dev, &buts);
+       ret = do_blk_trace_setup(q, name, dev, bdev, &buts);
        if (ret)
                return ret;
 
@@ -582,7 +600,7 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg)
        switch (cmd) {
        case BLKTRACESETUP:
                bdevname(bdev, b);
-               ret = blk_trace_setup(q, b, bdev->bd_dev, arg);
+               ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg);
                break;
        case BLKTRACESTART:
                start = 1;
@@ -809,7 +827,6 @@ static void blk_add_trace_split(struct request_queue *q, struct bio *bio,
  * @bio:       the source bio
  * @dev:       target device
  * @from:      source sector
- * @to:                target sector
  *
  * Description:
  *     Device mapper or raid target sometimes need to split a bio because
@@ -817,7 +834,7 @@ static void blk_add_trace_split(struct request_queue *q, struct bio *bio,
  *
  **/
 static void blk_add_trace_remap(struct request_queue *q, struct bio *bio,
-                                      dev_t dev, sector_t from, sector_t to)
+                                      dev_t dev, sector_t from)
 {
        struct blk_trace *bt = q->blk_trace;
        struct blk_io_trace_remap r;
@@ -825,12 +842,13 @@ static void blk_add_trace_remap(struct request_queue *q, struct bio *bio,
        if (likely(!bt))
                return;
 
-       r.device = cpu_to_be32(dev);
-       r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev);
-       r.sector = cpu_to_be64(to);
+       r.device_from = cpu_to_be32(dev);
+       r.device_to   = cpu_to_be32(bio->bi_bdev->bd_dev);
+       r.sector_from = cpu_to_be64(from);
 
-       __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP,
-                       !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r);
+       __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw,
+                       BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE),
+                       sizeof(r), &r);
 }
 
 /**
@@ -971,6 +989,16 @@ static inline const void *pdu_start(const struct trace_entry *ent)
        return te_blk_io_trace(ent) + 1;
 }
 
+static inline u32 t_action(const struct trace_entry *ent)
+{
+       return te_blk_io_trace(ent)->action;
+}
+
+static inline u32 t_bytes(const struct trace_entry *ent)
+{
+       return te_blk_io_trace(ent)->bytes;
+}
+
 static inline u32 t_sec(const struct trace_entry *ent)
 {
        return te_blk_io_trace(ent)->bytes >> 9;
@@ -996,11 +1024,11 @@ static void get_pdu_remap(const struct trace_entry *ent,
                          struct blk_io_trace_remap *r)
 {
        const struct blk_io_trace_remap *__r = pdu_start(ent);
-       __u64 sector = __r->sector;
+       __u64 sector_from = __r->sector_from;
 
-       r->device = be32_to_cpu(__r->device);
        r->device_from = be32_to_cpu(__r->device_from);
-       r->sector = be64_to_cpu(sector);
+       r->device_to   = be32_to_cpu(__r->device_to);
+       r->sector_from = be64_to_cpu(sector_from);
 }
 
 typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act);
@@ -1031,36 +1059,98 @@ static int blk_log_action(struct trace_iterator *iter, const char *act)
                                MAJOR(t->device), MINOR(t->device), act, rwbs);
 }
 
+static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent)
+{
+       const unsigned char *pdu_buf;
+       int pdu_len;
+       int i, end, ret;
+
+       pdu_buf = pdu_start(ent);
+       pdu_len = te_blk_io_trace(ent)->pdu_len;
+
+       if (!pdu_len)
+               return 1;
+
+       /* find the last zero that needs to be printed */
+       for (end = pdu_len - 1; end >= 0; end--)
+               if (pdu_buf[end])
+                       break;
+       end++;
+
+       if (!trace_seq_putc(s, '('))
+               return 0;
+
+       for (i = 0; i < pdu_len; i++) {
+
+               ret = trace_seq_printf(s, "%s%02x",
+                                      i == 0 ? "" : " ", pdu_buf[i]);
+               if (!ret)
+                       return ret;
+
+               /*
+                * stop when the rest is just zeroes and indicate so
+                * with a ".." appended
+                */
+               if (i == end && end != pdu_len - 1)
+                       return trace_seq_puts(s, " ..) ");
+       }
+
+       return trace_seq_puts(s, ") ");
+}
+
 static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent)
 {
        char cmd[TASK_COMM_LEN];
 
        trace_find_cmdline(ent->pid, cmd);
 
-       if (t_sec(ent))
-               return trace_seq_printf(s, "%llu + %u [%s]\n",
-                                       t_sector(ent), t_sec(ent), cmd);
-       return trace_seq_printf(s, "[%s]\n", cmd);
+       if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) {
+               int ret;
+
+               ret = trace_seq_printf(s, "%u ", t_bytes(ent));
+               if (!ret)
+                       return 0;
+               ret = blk_log_dump_pdu(s, ent);
+               if (!ret)
+                       return 0;
+               return trace_seq_printf(s, "[%s]\n", cmd);
+       } else {
+               if (t_sec(ent))
+                       return trace_seq_printf(s, "%llu + %u [%s]\n",
+                                               t_sector(ent), t_sec(ent), cmd);
+               return trace_seq_printf(s, "[%s]\n", cmd);
+       }
 }
 
 static int blk_log_with_error(struct trace_seq *s,
                              const struct trace_entry *ent)
 {
-       if (t_sec(ent))
-               return trace_seq_printf(s, "%llu + %u [%d]\n", t_sector(ent),
-                                       t_sec(ent), t_error(ent));
-       return trace_seq_printf(s, "%llu [%d]\n", t_sector(ent), t_error(ent));
+       if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) {
+               int ret;
+
+               ret = blk_log_dump_pdu(s, ent);
+               if (ret)
+                       return trace_seq_printf(s, "[%d]\n", t_error(ent));
+               return 0;
+       } else {
+               if (t_sec(ent))
+                       return trace_seq_printf(s, "%llu + %u [%d]\n",
+                                               t_sector(ent),
+                                               t_sec(ent), t_error(ent));
+               return trace_seq_printf(s, "%llu [%d]\n",
+                                       t_sector(ent), t_error(ent));
+       }
 }
 
 static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent)
 {
-       struct blk_io_trace_remap r = { .device = 0, };
+       struct blk_io_trace_remap r = { .device_from = 0, };
 
        get_pdu_remap(ent, &r);
        return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n",
-                              t_sector(ent),
-                              t_sec(ent), MAJOR(r.device), MINOR(r.device),
-                              (unsigned long long)r.sector);
+                               t_sector(ent), t_sec(ent),
+                               MAJOR(r.device_from), MINOR(r.device_from),
+                               (unsigned long long)r.sector_from);
 }
 
 static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent)
@@ -1117,7 +1207,6 @@ static void blk_tracer_print_header(struct seq_file *m)
 static void blk_tracer_start(struct trace_array *tr)
 {
        blk_tracer_enabled = true;
-       trace_flags &= ~TRACE_ITER_CONTEXT_INFO;
 }
 
 static int blk_tracer_init(struct trace_array *tr)
@@ -1130,7 +1219,6 @@ static int blk_tracer_init(struct trace_array *tr)
 static void blk_tracer_stop(struct trace_array *tr)
 {
        blk_tracer_enabled = false;
-       trace_flags |= TRACE_ITER_CONTEXT_INFO;
 }
 
 static void blk_tracer_reset(struct trace_array *tr)
@@ -1182,7 +1270,7 @@ static enum print_line_t print_one_line(struct trace_iterator *iter,
        }
 
        if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act)))
-               ret = trace_seq_printf(s, "Bad pc action %x\n", what);
+               ret = trace_seq_printf(s, "Unknown action %x\n", what);
        else {
                ret = log_action(iter, what2act[what].act[long_act]);
                if (ret)
@@ -1195,9 +1283,6 @@ out:
 static enum print_line_t blk_trace_event_print(struct trace_iterator *iter,
                                               int flags)
 {
-       if (!trace_print_context(iter))
-               return TRACE_TYPE_PARTIAL_LINE;
-
        return print_one_line(iter, false);
 }
 
@@ -1232,6 +1317,18 @@ static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter)
        return print_one_line(iter, true);
 }
 
+static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set)
+{
+       /* don't output context-info for blk_classic output */
+       if (bit == TRACE_BLK_OPT_CLASSIC) {
+               if (set)
+                       trace_flags &= ~TRACE_ITER_CONTEXT_INFO;
+               else
+                       trace_flags |= TRACE_ITER_CONTEXT_INFO;
+       }
+       return 0;
+}
+
 static struct tracer blk_tracer __read_mostly = {
        .name           = "blk",
        .init           = blk_tracer_init,
@@ -1241,6 +1338,7 @@ static struct tracer blk_tracer __read_mostly = {
        .print_header   = blk_tracer_print_header,
        .print_line     = blk_tracer_print_line,
        .flags          = &blk_tracer_flags,
+       .set_flag       = blk_tracer_set_flag,
 };
 
 static struct trace_event trace_blk_event = {
@@ -1285,7 +1383,8 @@ static int blk_trace_remove_queue(struct request_queue *q)
 /*
  * Setup everything required to start tracing
  */
-static int blk_trace_setup_queue(struct request_queue *q, dev_t dev)
+static int blk_trace_setup_queue(struct request_queue *q,
+                                struct block_device *bdev)
 {
        struct blk_trace *old_bt, *bt = NULL;
        int ret = -ENOMEM;
@@ -1298,9 +1397,10 @@ static int blk_trace_setup_queue(struct request_queue *q, dev_t dev)
        if (!bt->msg_data)
                goto free_bt;
 
-       bt->dev = dev;
+       bt->dev = bdev->bd_dev;
        bt->act_mask = (u16)-1;
-       bt->end_lba = -1ULL;
+
+       blk_trace_setup_lba(bt, bdev);
 
        old_bt = xchg(&q->blk_trace, bt);
        if (old_bt != NULL) {
@@ -1517,7 +1617,7 @@ static ssize_t sysfs_blk_trace_attr_store(struct device *dev,
 
        if (attr == &dev_attr_enable) {
                if (value)
-                       ret = blk_trace_setup_queue(q, bdev->bd_dev);
+                       ret = blk_trace_setup_queue(q, bdev);
                else
                        ret = blk_trace_remove_queue(q);
                goto out_unlock_bdev;
@@ -1525,7 +1625,7 @@ static ssize_t sysfs_blk_trace_attr_store(struct device *dev,
 
        ret = 0;
        if (q->blk_trace == NULL)
-               ret = blk_trace_setup_queue(q, bdev->bd_dev);
+               ret = blk_trace_setup_queue(q, bdev);
 
        if (ret == 0) {
                if (attr == &dev_attr_act_mask)
@@ -1548,3 +1648,77 @@ out:
        return ret ? ret : count;
 }
 
+int blk_trace_init_sysfs(struct device *dev)
+{
+       return sysfs_create_group(&dev->kobj, &blk_trace_attr_group);
+}
+
+#endif /* CONFIG_BLK_DEV_IO_TRACE */
+
+#ifdef CONFIG_EVENT_TRACING
+
+void blk_dump_cmd(char *buf, struct request *rq)
+{
+       int i, end;
+       int len = rq->cmd_len;
+       unsigned char *cmd = rq->cmd;
+
+       if (!blk_pc_request(rq)) {
+               buf[0] = '\0';
+               return;
+       }
+
+       for (end = len - 1; end >= 0; end--)
+               if (cmd[end])
+                       break;
+       end++;
+
+       for (i = 0; i < len; i++) {
+               buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]);
+               if (i == end && end != len - 1) {
+                       sprintf(buf, " ..");
+                       break;
+               }
+       }
+}
+
+void blk_fill_rwbs(char *rwbs, u32 rw, int bytes)
+{
+       int i = 0;
+
+       if (rw & WRITE)
+               rwbs[i++] = 'W';
+       else if (rw & 1 << BIO_RW_DISCARD)
+               rwbs[i++] = 'D';
+       else if (bytes)
+               rwbs[i++] = 'R';
+       else
+               rwbs[i++] = 'N';
+
+       if (rw & 1 << BIO_RW_AHEAD)
+               rwbs[i++] = 'A';
+       if (rw & 1 << BIO_RW_BARRIER)
+               rwbs[i++] = 'B';
+       if (rw & 1 << BIO_RW_SYNCIO)
+               rwbs[i++] = 'S';
+       if (rw & 1 << BIO_RW_META)
+               rwbs[i++] = 'M';
+
+       rwbs[i] = '\0';
+}
+
+void blk_fill_rwbs_rq(char *rwbs, struct request *rq)
+{
+       int rw = rq->cmd_flags & 0x03;
+       int bytes;
+
+       if (blk_discard_rq(rq))
+               rw |= (1 << BIO_RW_DISCARD);
+
+       bytes = blk_rq_bytes(rq);
+
+       blk_fill_rwbs(rwbs, rw, bytes);
+}
+
+#endif /* CONFIG_EVENT_TRACING */
+