Re: [PATCH] SCHED: attribute page lock and waitqueue functions as sched

[Matthew Wilcox]

On Thu, Nov 04, 2021 at 02:47:03AM +0800, Jimmy Shiu wrote:
> +++ b/mm/filemap.c
> @@ -1271,7 +1271,7 @@ static inline bool folio_trylock_flag(struct folio *folio, int bit_nr,
>  /* How many times do we accept lock stealing from under a waiter? */
>  int sysctl_page_lock_unfairness = 5;
>  
> -static inline int folio_wait_bit_common(struct folio *folio, int bit_nr,
> +static inline __sched int folio_wait_bit_common(struct folio *folio, int bit_nr,

It's not clear to me whether folio_wait_bit_common() needs to be marked
as __sched or whether marking its callers is sufficient, but I'm pretty
sure you forgot to mark put_and_wait_on_page_locked() as __sched, which
is an important one as it's now where we wait for readahead to finish
when reading a file.