| Message ID | 6bd882fd0562b8b18600629f7d0504f98c560dcf.1654792073.git.johannes.thumshirn@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | btrfs: add tracepoints for ordered extents | expand |
On Thu, Jun 09, 2022 at 09:28:04AM -0700, Johannes Thumshirn wrote: > When debugging a reference counting issue with ordered extents, I've found > we're lacking a lot of tracepoint coverage in the ordered-extent code. > > Close these gaps by adding tracepoints after every refcount_inc() in the > ordered-extent code. > > Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Looks good, I see the new tracepoints. I think it would be helpful for posterity to motivate why refcount_inc is what we want to trace. Reviewed-by: Boris Burkov <boris@bur.io> > --- > fs/btrfs/ordered-data.c | 19 +++++++++-- > include/trace/events/btrfs.h | 64 ++++++++++++++++++++++++++++++++++++ > 2 files changed, 80 insertions(+), 3 deletions(-) > > diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c > index dc88d2b3721f..41b3bc44c92b 100644 > --- a/fs/btrfs/ordered-data.c > +++ b/fs/btrfs/ordered-data.c > @@ -401,6 +401,7 @@ void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode, > set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags); > cond_wake_up(&entry->wait); > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_mark_finished(inode, entry); > spin_unlock_irqrestore(&tree->lock, flags); > btrfs_init_work(&entry->work, finish_func, NULL, NULL); > btrfs_queue_work(wq, &entry->work); > @@ -473,6 +474,7 @@ bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode, > if (finished && cached && entry) { > *cached = entry; > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_dec_test_pending(inode, entry); > } > spin_unlock_irqrestore(&tree->lock, flags); > return finished; > @@ -807,8 +809,10 @@ struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *ino > entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); > if (!in_range(file_offset, entry->file_offset, entry->num_bytes)) > entry = NULL; > - if (entry) > + if (entry) { > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup(inode, entry); > + } > out: > spin_unlock_irqrestore(&tree->lock, flags); > return entry; > @@ -848,8 +852,10 @@ struct btrfs_ordered_extent *btrfs_lookup_ordered_range( > break; > } > out: > - if (entry) > + if (entry) { > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup_range(inode, entry); > + } > spin_unlock_irq(&tree->lock); > return entry; > } > @@ -878,6 +884,7 @@ void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode, > ASSERT(list_empty(&ordered->log_list)); > list_add_tail(&ordered->log_list, list); > refcount_inc(&ordered->refs); > + trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered); > } > spin_unlock_irq(&tree->lock); > } > @@ -901,6 +908,7 @@ btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset) > > entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup_first(inode, entry); > out: > spin_unlock_irq(&tree->lock); > return entry; > @@ -975,8 +983,11 @@ struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range( > /* No ordered extent in the range */ > entry = NULL; > out: > - if (entry) > + if (entry) { > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup_first_range(inode, entry); > + } > + > spin_unlock_irq(&tree->lock); > return entry; > } > @@ -1055,6 +1066,8 @@ int btrfs_split_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pre, > struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); > int ret = 0; > > + trace_btrfs_ordered_extent_split(BTRFS_I(inode), ordered); > + > spin_lock_irq(&tree->lock); > /* Remove from tree once */ > node = &ordered->rb_node; > diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h > index 29fa8ea2cc0f..73df80d462dc 100644 > --- a/include/trace/events/btrfs.h > +++ b/include/trace/events/btrfs.h > @@ -598,6 +598,70 @@ DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_put, > TP_ARGS(inode, ordered) > ); > > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_range, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_first_range, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_for_logging, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_first, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_split, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_dec_test_pending, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_mark_finished, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > DECLARE_EVENT_CLASS(btrfs__writepage, > > TP_PROTO(const struct page *page, const struct inode *inode, > -- > 2.35.3 >
On 2022/6/10 00:28, Johannes Thumshirn wrote: > When debugging a reference counting issue with ordered extents, I've found > we're lacking a lot of tracepoint coverage in the ordered-extent code. > > Close these gaps by adding tracepoints after every refcount_inc() in the > ordered-extent code. > > Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> > --- > fs/btrfs/ordered-data.c | 19 +++++++++-- > include/trace/events/btrfs.h | 64 ++++++++++++++++++++++++++++++++++++ > 2 files changed, 80 insertions(+), 3 deletions(-) > > diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c > index dc88d2b3721f..41b3bc44c92b 100644 > --- a/fs/btrfs/ordered-data.c > +++ b/fs/btrfs/ordered-data.c > @@ -401,6 +401,7 @@ void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode, > set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags); > cond_wake_up(&entry->wait); > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_mark_finished(inode, entry); > spin_unlock_irqrestore(&tree->lock, flags); > btrfs_init_work(&entry->work, finish_func, NULL, NULL); > btrfs_queue_work(wq, &entry->work); > @@ -473,6 +474,7 @@ bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode, > if (finished && cached && entry) { > *cached = entry; > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_dec_test_pending(inode, entry); > } > spin_unlock_irqrestore(&tree->lock, flags); > return finished; > @@ -807,8 +809,10 @@ struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *ino > entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); > if (!in_range(file_offset, entry->file_offset, entry->num_bytes)) > entry = NULL; > - if (entry) > + if (entry) { > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup(inode, entry); > + } > out: > spin_unlock_irqrestore(&tree->lock, flags); > return entry; > @@ -848,8 +852,10 @@ struct btrfs_ordered_extent *btrfs_lookup_ordered_range( > break; > } > out: > - if (entry) > + if (entry) { > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup_range(inode, entry); > + } > spin_unlock_irq(&tree->lock); > return entry; > } > @@ -878,6 +884,7 @@ void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode, > ASSERT(list_empty(&ordered->log_list)); > list_add_tail(&ordered->log_list, list); > refcount_inc(&ordered->refs); > + trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered); > } > spin_unlock_irq(&tree->lock); > } > @@ -901,6 +908,7 @@ btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset) > > entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup_first(inode, entry); > out: > spin_unlock_irq(&tree->lock); > return entry; > @@ -975,8 +983,11 @@ struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range( > /* No ordered extent in the range */ > entry = NULL; > out: > - if (entry) > + if (entry) { > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup_first_range(inode, entry); > + } > + > spin_unlock_irq(&tree->lock); > return entry; > } > @@ -1055,6 +1066,8 @@ int btrfs_split_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pre, > struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); > int ret = 0; > > + trace_btrfs_ordered_extent_split(BTRFS_I(inode), ordered); I guess this doesn't have all the info for this split event? Like pre/post values? Although we will call clone_ordered_extent() which will call btrfs_add_ordered_extent() and trigger the event for add. It still doesn't really show the pre/post values directly. Is there better way to just add extra members for the existing trace event class? If not, I guess that's all what we can do right now... Thanks, Qu > + > spin_lock_irq(&tree->lock); > /* Remove from tree once */ > node = &ordered->rb_node; > diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h > index 29fa8ea2cc0f..73df80d462dc 100644 > --- a/include/trace/events/btrfs.h > +++ b/include/trace/events/btrfs.h > @@ -598,6 +598,70 @@ DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_put, > TP_ARGS(inode, ordered) > ); > > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_range, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_first_range, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_for_logging, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_first, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_split, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_dec_test_pending, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_mark_finished, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > DECLARE_EVENT_CLASS(btrfs__writepage, > > TP_PROTO(const struct page *page, const struct inode *inode,
On 10.06.22 11:17, Qu Wenruo wrote: >> + trace_btrfs_ordered_extent_split(BTRFS_I(inode), ordered); > > I guess this doesn't have all the info for this split event? > Like pre/post values? > > Although we will call clone_ordered_extent() which will call > btrfs_add_ordered_extent() and trigger the event for add. > > It still doesn't really show the pre/post values directly. > Yup, unfortunately you need to do the math on your own. > Is there better way to just add extra members for the existing trace > event class? > If not, I guess that's all what we can do right now... > Not that I know of, hence why I had to do it this way.
On 2022/6/10 18:07, Johannes Thumshirn wrote: > On 10.06.22 11:17, Qu Wenruo wrote: >>> + trace_btrfs_ordered_extent_split(BTRFS_I(inode), ordered); >> >> I guess this doesn't have all the info for this split event? >> Like pre/post values? >> >> Although we will call clone_ordered_extent() which will call >> btrfs_add_ordered_extent() and trigger the event for add. >> >> It still doesn't really show the pre/post values directly. >> > > Yup, unfortunately you need to do the math on your own. > >> Is there better way to just add extra members for the existing trace >> event class? >> If not, I guess that's all what we can do right now... >> > > Not that I know of, hence why I had to do it this way. OK, then it looks fine to me. Reviewed-by: Qu Wenruo <wqu@suse.com> Thanks, Qu
On 6/9/22 21:58, Johannes Thumshirn wrote: > When debugging a reference counting issue with ordered extents, I've found > we're lacking a lot of tracepoint coverage in the ordered-extent code. > > Close these gaps by adding tracepoints after every refcount_inc() in the > ordered-extent code. > > Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> LGTM Reviewed-by: Anand Jain <anand.jain@oracle.com> > --- > fs/btrfs/ordered-data.c | 19 +++++++++-- > include/trace/events/btrfs.h | 64 ++++++++++++++++++++++++++++++++++++ > 2 files changed, 80 insertions(+), 3 deletions(-) > > diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c > index dc88d2b3721f..41b3bc44c92b 100644 > --- a/fs/btrfs/ordered-data.c > +++ b/fs/btrfs/ordered-data.c > @@ -401,6 +401,7 @@ void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode, > set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags); > cond_wake_up(&entry->wait); > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_mark_finished(inode, entry); > spin_unlock_irqrestore(&tree->lock, flags); > btrfs_init_work(&entry->work, finish_func, NULL, NULL); > btrfs_queue_work(wq, &entry->work); > @@ -473,6 +474,7 @@ bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode, > if (finished && cached && entry) { > *cached = entry; > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_dec_test_pending(inode, entry); > } > spin_unlock_irqrestore(&tree->lock, flags); > return finished; > @@ -807,8 +809,10 @@ struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *ino > entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); > if (!in_range(file_offset, entry->file_offset, entry->num_bytes)) > entry = NULL; > - if (entry) > + if (entry) { > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup(inode, entry); > + } > out: > spin_unlock_irqrestore(&tree->lock, flags); > return entry; > @@ -848,8 +852,10 @@ struct btrfs_ordered_extent *btrfs_lookup_ordered_range( > break; > } > out: > - if (entry) > + if (entry) { > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup_range(inode, entry); > + } > spin_unlock_irq(&tree->lock); > return entry; > } > @@ -878,6 +884,7 @@ void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode, > ASSERT(list_empty(&ordered->log_list)); > list_add_tail(&ordered->log_list, list); > refcount_inc(&ordered->refs); > + trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered); > } > spin_unlock_irq(&tree->lock); > } > @@ -901,6 +908,7 @@ btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset) > > entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup_first(inode, entry); > out: > spin_unlock_irq(&tree->lock); > return entry; > @@ -975,8 +983,11 @@ struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range( > /* No ordered extent in the range */ > entry = NULL; > out: > - if (entry) > + if (entry) { > refcount_inc(&entry->refs); > + trace_btrfs_ordered_extent_lookup_first_range(inode, entry); > + } > + > spin_unlock_irq(&tree->lock); > return entry; > } > @@ -1055,6 +1066,8 @@ int btrfs_split_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pre, > struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); > int ret = 0; > > + trace_btrfs_ordered_extent_split(BTRFS_I(inode), ordered); > + > spin_lock_irq(&tree->lock); > /* Remove from tree once */ > node = &ordered->rb_node; > diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h > index 29fa8ea2cc0f..73df80d462dc 100644 > --- a/include/trace/events/btrfs.h > +++ b/include/trace/events/btrfs.h > @@ -598,6 +598,70 @@ DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_put, > TP_ARGS(inode, ordered) > ); > > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_range, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_first_range, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_for_logging, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_first, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_split, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_dec_test_pending, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_mark_finished, > + > + TP_PROTO(const struct btrfs_inode *inode, > + const struct btrfs_ordered_extent *ordered), > + > + TP_ARGS(inode, ordered) > +); > + > DECLARE_EVENT_CLASS(btrfs__writepage, > > TP_PROTO(const struct page *page, const struct inode *inode,
On Thu, Jun 09, 2022 at 09:28:04AM -0700, Johannes Thumshirn wrote: > When debugging a reference counting issue with ordered extents, I've found > we're lacking a lot of tracepoint coverage in the ordered-extent code. > > Close these gaps by adding tracepoints after every refcount_inc() in the > ordered-extent code. > > Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Added to misc-next, thanks.
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c index dc88d2b3721f..41b3bc44c92b 100644 --- a/fs/btrfs/ordered-data.c +++ b/fs/btrfs/ordered-data.c @@ -401,6 +401,7 @@ void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode, set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags); cond_wake_up(&entry->wait); refcount_inc(&entry->refs); + trace_btrfs_ordered_extent_mark_finished(inode, entry); spin_unlock_irqrestore(&tree->lock, flags); btrfs_init_work(&entry->work, finish_func, NULL, NULL); btrfs_queue_work(wq, &entry->work); @@ -473,6 +474,7 @@ bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode, if (finished && cached && entry) { *cached = entry; refcount_inc(&entry->refs); + trace_btrfs_ordered_extent_dec_test_pending(inode, entry); } spin_unlock_irqrestore(&tree->lock, flags); return finished; @@ -807,8 +809,10 @@ struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *ino entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); if (!in_range(file_offset, entry->file_offset, entry->num_bytes)) entry = NULL; - if (entry) + if (entry) { refcount_inc(&entry->refs); + trace_btrfs_ordered_extent_lookup(inode, entry); + } out: spin_unlock_irqrestore(&tree->lock, flags); return entry; @@ -848,8 +852,10 @@ struct btrfs_ordered_extent *btrfs_lookup_ordered_range( break; } out: - if (entry) + if (entry) { refcount_inc(&entry->refs); + trace_btrfs_ordered_extent_lookup_range(inode, entry); + } spin_unlock_irq(&tree->lock); return entry; } @@ -878,6 +884,7 @@ void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode, ASSERT(list_empty(&ordered->log_list)); list_add_tail(&ordered->log_list, list); refcount_inc(&ordered->refs); + trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered); } spin_unlock_irq(&tree->lock); } @@ -901,6 +908,7 @@ btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset) entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); refcount_inc(&entry->refs); + trace_btrfs_ordered_extent_lookup_first(inode, entry); out: spin_unlock_irq(&tree->lock); return entry; @@ -975,8 +983,11 @@ struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range( /* No ordered extent in the range */ entry = NULL; out: - if (entry) + if (entry) { refcount_inc(&entry->refs); + trace_btrfs_ordered_extent_lookup_first_range(inode, entry); + } + spin_unlock_irq(&tree->lock); return entry; } @@ -1055,6 +1066,8 @@ int btrfs_split_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pre, struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); int ret = 0; + trace_btrfs_ordered_extent_split(BTRFS_I(inode), ordered); + spin_lock_irq(&tree->lock); /* Remove from tree once */ node = &ordered->rb_node; diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h index 29fa8ea2cc0f..73df80d462dc 100644 --- a/include/trace/events/btrfs.h +++ b/include/trace/events/btrfs.h @@ -598,6 +598,70 @@ DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_put, TP_ARGS(inode, ordered) ); +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup, + + TP_PROTO(const struct btrfs_inode *inode, + const struct btrfs_ordered_extent *ordered), + + TP_ARGS(inode, ordered) +); + +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_range, + + TP_PROTO(const struct btrfs_inode *inode, + const struct btrfs_ordered_extent *ordered), + + TP_ARGS(inode, ordered) +); + +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_first_range, + + TP_PROTO(const struct btrfs_inode *inode, + const struct btrfs_ordered_extent *ordered), + + TP_ARGS(inode, ordered) +); + +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_for_logging, + + TP_PROTO(const struct btrfs_inode *inode, + const struct btrfs_ordered_extent *ordered), + + TP_ARGS(inode, ordered) +); + +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_lookup_first, + + TP_PROTO(const struct btrfs_inode *inode, + const struct btrfs_ordered_extent *ordered), + + TP_ARGS(inode, ordered) +); + +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_split, + + TP_PROTO(const struct btrfs_inode *inode, + const struct btrfs_ordered_extent *ordered), + + TP_ARGS(inode, ordered) +); + +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_dec_test_pending, + + TP_PROTO(const struct btrfs_inode *inode, + const struct btrfs_ordered_extent *ordered), + + TP_ARGS(inode, ordered) +); + +DEFINE_EVENT(btrfs__ordered_extent, btrfs_ordered_extent_mark_finished, + + TP_PROTO(const struct btrfs_inode *inode, + const struct btrfs_ordered_extent *ordered), + + TP_ARGS(inode, ordered) +); + DECLARE_EVENT_CLASS(btrfs__writepage, TP_PROTO(const struct page *page, const struct inode *inode,
When debugging a reference counting issue with ordered extents, I've found we're lacking a lot of tracepoint coverage in the ordered-extent code. Close these gaps by adding tracepoints after every refcount_inc() in the ordered-extent code. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> --- fs/btrfs/ordered-data.c | 19 +++++++++-- include/trace/events/btrfs.h | 64 ++++++++++++++++++++++++++++++++++++ 2 files changed, 80 insertions(+), 3 deletions(-)