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authorLi Zefan <lizf@cn.fujitsu.com>2009-04-14 13:59:34 +0800
committerIngo Molnar <mingo@elte.hu>2009-04-16 10:10:58 +0200
commit9908c30997b8a73c95f836170b9998dae9aa3f4a (patch)
treed44d6d663a150c26b5d7be6edebb1abbb88ecc94 /kernel/trace/blktrace.c
parentd0deef5b14af7d5bbd0003a0a2a1a32326e20a6d (diff)
downloadlinux-9908c30997b8a73c95f836170b9998dae9aa3f4a.tar.bz2
blktrace: support per-partition tracing for ftrace plugin
The previous patch adds support to trace a single partition for relay+ioctl blktrace, and this patch is for ftrace plugin blktrace: # echo 1 > /sys/block/sda/sda7/enable # cat start_lba 102398373 # cat end_lba 102703545 Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Shawn Du <duyuyang@gmail.com> Cc: Jens Axboe <jens.axboe@oracle.com> LKML-Reference: <49E42646.4060608@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/trace/blktrace.c')
-rw-r--r--kernel/trace/blktrace.c39
1 files changed, 25 insertions, 14 deletions
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index e932654cf590..d10989880520 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -403,6 +403,23 @@ 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
*/
@@ -413,7 +430,6 @@ int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
struct blk_trace *old_bt, *bt = NULL;
struct dentry *dir = NULL;
int ret, i;
- struct hd_struct *part = NULL;
if (!buts->buf_size || !buts->buf_nr)
return -EINVAL;
@@ -482,14 +498,7 @@ int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
if (!bt->act_mask)
bt->act_mask = (u16) -1;
- 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->end_lba = -1ULL;
+ blk_trace_setup_lba(bt, bdev);
/* overwrite with user settings */
if (buts->start_lba)
@@ -1370,7 +1379,8 @@ 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;
@@ -1383,9 +1393,10 @@ 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) {
@@ -1602,7 +1613,7 @@ 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;
@@ -1610,7 +1621,7 @@ 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)