On Thu, 6 Jun 2024 11:35:47 +0800 Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> wrote: > Factor out balance_wb_limits to remove repeated code > > Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> > --- > mm/page-writeback.c | 25 +++++++++++++++++-------- > 1 file changed, 17 insertions(+), 8 deletions(-) > > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index bf050abd9053..f611272d3c5b 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -1783,6 +1783,21 @@ static inline void wb_dirty_exceeded(struct dirty_throttle_control *dtc, > ((dtc->dirty > dtc->thresh) || strictlimit); > } > > +/* > + * The limits fileds dirty_exceeded and pos_ratio won't be updated if wb is > + * in freerun state. Please don't use these invalid fileds in freerun case. s/fileds/fields/. I queued a fix for this. > + */ > +static void balance_wb_limits(struct dirty_throttle_control *dtc, > + bool strictlimit) > +{ > + wb_dirty_freerun(dtc, strictlimit); > + if (dtc->freerun) > + return; > + > + wb_dirty_exceeded(dtc, strictlimit); > + wb_position_ratio(dtc); > +} > + > /* > * balance_dirty_pages() must be called by processes which are generating dirty > * data. It looks at the number of dirty pages in the machine and will force > @@ -1869,12 +1884,9 @@ static int balance_dirty_pages(struct bdi_writeback *wb, > * Calculate global domain's pos_ratio and select the > * global dtc by default. > */ > - wb_dirty_freerun(gdtc, strictlimit); > + balance_wb_limits(gdtc, strictlimit); > if (gdtc->freerun) > goto free_running; Would it be neater to do if (balance_wb_limits(...)) goto free_running; ? That would require a balance_wb_limits() comment update and probably name change. Just a thought.