diff options
author | Yafang Shao <laoar.shao@gmail.com> | 2019-05-13 17:23:11 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-14 09:47:51 -0700 |
commit | 19343b5bdd16ad4ae6b845ef829f68b683c4dfb5 (patch) | |
tree | f6e36441b6b86ea3e4d499ebc35e3e7c9b6bd203 /mm/page-writeback.c | |
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>
Diffstat (limited to 'mm/page-writeback.c')
-rw-r--r-- | mm/page-writeback.c | 12 |
1 files changed, 12 insertions, 0 deletions
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. |