diff options
author | Yafang Shao <laoar.shao@gmail.com> | 2019-05-13 17:23:11 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-14 09:47:51 -0700 |
commit | 19343b5bdd16ad4ae6b845ef829f68b683c4dfb5 (patch) | |
tree | f6e36441b6b86ea3e4d499ebc35e3e7c9b6bd203 | |
parent | 60b62ff7cc4217ac3de76535fa4c1510a798dbcb (diff) |
mm/page-writeback: introduce tracepoint for wait_on_page_writeback()
Recently there have been some hung tasks on our server due to
wait_on_page_writeback(), and we want to know the details of this
PG_writeback, i.e. this page is writing back to which device. But it is
not so convenient to get the details.
I think it would be better to introduce a tracepoint for diagnosing the
writeback details.
Link: http://lkml.kernel.org/r/1556274402-19018-1-git-send-email-laoar.shao@gmail.com
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | include/linux/pagemap.h | 10 | ||||
-rw-r--r-- | include/trace/events/writeback.h | 16 | ||||
-rw-r--r-- | mm/page-writeback.c | 12 |
3 files changed, 28 insertions, 10 deletions
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 2e8438a1216a..112f15bb5907 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -540,15 +540,7 @@ static inline int wait_on_page_locked_killable(struct page *page) extern void put_and_wait_on_page_locked(struct page *page); -/* - * Wait for a page to complete writeback - */ -static inline void wait_on_page_writeback(struct page *page) -{ - if (PageWriteback(page)) - wait_on_page_bit(page, PG_writeback); -} - +void wait_on_page_writeback(struct page *page); extern void end_page_writeback(struct page *page); void wait_for_stable_page(struct page *page); diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h index 32db72c7c055..aa7f3aeac740 100644 --- a/include/trace/events/writeback.h +++ b/include/trace/events/writeback.h @@ -53,7 +53,7 @@ WB_WORK_REASON struct wb_writeback_work; -TRACE_EVENT(writeback_dirty_page, +DECLARE_EVENT_CLASS(writeback_page_template, TP_PROTO(struct page *page, struct address_space *mapping), @@ -79,6 +79,20 @@ TRACE_EVENT(writeback_dirty_page, ) ); +DEFINE_EVENT(writeback_page_template, writeback_dirty_page, + + TP_PROTO(struct page *page, struct address_space *mapping), + + TP_ARGS(page, mapping) +); + +DEFINE_EVENT(writeback_page_template, wait_on_page_writeback, + + TP_PROTO(struct page *page, struct address_space *mapping), + + TP_ARGS(page, mapping) +); + DECLARE_EVENT_CLASS(writeback_dirty_inode_template, TP_PROTO(struct inode *inode, int flags), diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 9f61dfec6a1f..07656485c0e6 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2808,6 +2808,18 @@ int __test_set_page_writeback(struct page *page, bool keep_write) } EXPORT_SYMBOL(__test_set_page_writeback); +/* + * Wait for a page to complete writeback + */ +void wait_on_page_writeback(struct page *page) +{ + if (PageWriteback(page)) { + trace_wait_on_page_writeback(page, page_mapping(page)); + wait_on_page_bit(page, PG_writeback); + } +} +EXPORT_SYMBOL_GPL(wait_on_page_writeback); + /** * wait_for_stable_page() - wait for writeback to finish, if necessary. * @page: The page to wait on. |