| Message ID | 20220516164718.2419891-14-shr@fb.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | io-uring/xfs: support async buffered writes | expand |
On Mon 16-05-22 09:47:15, Stefan Roesch wrote: > This adds the function balance_dirty_pages_ratelimited_flags(). It adds > the parameter is_async to balance_dirty_pages_ratelimited(). In case > this is an async write, it will call _balance_diirty_pages() to > determine if write throttling needs to be enabled. If write throttling > is enabled, it retuns -EAGAIN, so the write request can be punted to > the io-uring worker. > > The new function is changed to return the sleep time, so callers can > observe if the write has been punted. > > For non-async writes the current behavior is maintained. > > Signed-off-by: Stefan Roesch <shr@fb.com> > --- > include/linux/writeback.h | 1 + > mm/page-writeback.c | 48 ++++++++++++++++++++++++++------------- > 2 files changed, 33 insertions(+), 16 deletions(-) > > diff --git a/include/linux/writeback.h b/include/linux/writeback.h > index fec248ab1fec..d589804bb3be 100644 > --- a/include/linux/writeback.h > +++ b/include/linux/writeback.h > @@ -373,6 +373,7 @@ unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh); > > void wb_update_bandwidth(struct bdi_writeback *wb); > void balance_dirty_pages_ratelimited(struct address_space *mapping); > +int balance_dirty_pages_ratelimited_flags(struct address_space *mapping, bool is_async); > bool wb_over_bg_thresh(struct bdi_writeback *wb); > > typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc, > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index cbb74c0666c6..78f1326f3f20 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -1877,28 +1877,17 @@ static DEFINE_PER_CPU(int, bdp_ratelimits); > */ > DEFINE_PER_CPU(int, dirty_throttle_leaks) = 0; > > -/** > - * balance_dirty_pages_ratelimited - balance dirty memory state > - * @mapping: address_space which was dirtied > - * > - * Processes which are dirtying memory should call in here once for each page > - * which was newly dirtied. The function will periodically check the system's > - * dirty state and will initiate writeback if needed. > - * > - * Once we're over the dirty memory limit we decrease the ratelimiting > - * by a lot, to prevent individual processes from overshooting the limit > - * by (ratelimit_pages) each. > - */ > -void balance_dirty_pages_ratelimited(struct address_space *mapping) > +int balance_dirty_pages_ratelimited_flags(struct address_space *mapping, bool is_async) Perhaps I'd call the other function balance_dirty_pages_ratelimited_async() and then keep balance_dirty_pages_ratelimited_flags() as an internal function. It is then more obvious at the external call sites what the call is about (unlike the true/false argument). Honza > { > struct inode *inode = mapping->host; > struct backing_dev_info *bdi = inode_to_bdi(inode); > struct bdi_writeback *wb = NULL; > int ratelimit; > + int ret = 0; > int *p; > > if (!(bdi->capabilities & BDI_CAP_WRITEBACK)) > - return; > + return ret; > > if (inode_cgwb_enabled(inode)) > wb = wb_get_create_current(bdi, GFP_KERNEL); > @@ -1937,10 +1926,37 @@ void balance_dirty_pages_ratelimited(struct address_space *mapping) > } > preempt_enable(); > > - if (unlikely(current->nr_dirtied >= ratelimit)) > - balance_dirty_pages(wb, current->nr_dirtied); > + if (unlikely(current->nr_dirtied >= ratelimit)) { > + if (is_async) { > + struct bdp_ctx ctx = { BDP_CTX_INIT(ctx, wb) }; > + > + ret = _balance_dirty_pages(wb, current->nr_dirtied, &ctx); > + if (ret) > + ret = -EAGAIN; > + } else { > + balance_dirty_pages(wb, current->nr_dirtied); > + } > + } > > wb_put(wb); > + return ret; > +} > + > +/** > + * balance_dirty_pages_ratelimited - balance dirty memory state > + * @mapping: address_space which was dirtied > + * > + * Processes which are dirtying memory should call in here once for each page > + * which was newly dirtied. The function will periodically check the system's > + * dirty state and will initiate writeback if needed. > + * > + * Once we're over the dirty memory limit we decrease the ratelimiting > + * by a lot, to prevent individual processes from overshooting the limit > + * by (ratelimit_pages) each. > + */ > +void balance_dirty_pages_ratelimited(struct address_space *mapping) > +{ > + balance_dirty_pages_ratelimited_flags(mapping, false); > } > EXPORT_SYMBOL(balance_dirty_pages_ratelimited); > > -- > 2.30.2 >
On 5/17/22 1:12 PM, Jan Kara wrote: > On Mon 16-05-22 09:47:15, Stefan Roesch wrote: >> This adds the function balance_dirty_pages_ratelimited_flags(). It adds >> the parameter is_async to balance_dirty_pages_ratelimited(). In case >> this is an async write, it will call _balance_diirty_pages() to >> determine if write throttling needs to be enabled. If write throttling >> is enabled, it retuns -EAGAIN, so the write request can be punted to >> the io-uring worker. >> >> The new function is changed to return the sleep time, so callers can >> observe if the write has been punted. >> >> For non-async writes the current behavior is maintained. >> >> Signed-off-by: Stefan Roesch <shr@fb.com> >> --- >> include/linux/writeback.h | 1 + >> mm/page-writeback.c | 48 ++++++++++++++++++++++++++------------- >> 2 files changed, 33 insertions(+), 16 deletions(-) >> >> diff --git a/include/linux/writeback.h b/include/linux/writeback.h >> index fec248ab1fec..d589804bb3be 100644 >> --- a/include/linux/writeback.h >> +++ b/include/linux/writeback.h >> @@ -373,6 +373,7 @@ unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh); >> >> void wb_update_bandwidth(struct bdi_writeback *wb); >> void balance_dirty_pages_ratelimited(struct address_space *mapping); >> +int balance_dirty_pages_ratelimited_flags(struct address_space *mapping, bool is_async); >> bool wb_over_bg_thresh(struct bdi_writeback *wb); >> >> typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc, >> diff --git a/mm/page-writeback.c b/mm/page-writeback.c >> index cbb74c0666c6..78f1326f3f20 100644 >> --- a/mm/page-writeback.c >> +++ b/mm/page-writeback.c >> @@ -1877,28 +1877,17 @@ static DEFINE_PER_CPU(int, bdp_ratelimits); >> */ >> DEFINE_PER_CPU(int, dirty_throttle_leaks) = 0; >> >> -/** >> - * balance_dirty_pages_ratelimited - balance dirty memory state >> - * @mapping: address_space which was dirtied >> - * >> - * Processes which are dirtying memory should call in here once for each page >> - * which was newly dirtied. The function will periodically check the system's >> - * dirty state and will initiate writeback if needed. >> - * >> - * Once we're over the dirty memory limit we decrease the ratelimiting >> - * by a lot, to prevent individual processes from overshooting the limit >> - * by (ratelimit_pages) each. >> - */ >> -void balance_dirty_pages_ratelimited(struct address_space *mapping) >> +int balance_dirty_pages_ratelimited_flags(struct address_space *mapping, bool is_async) > > Perhaps I'd call the other function balance_dirty_pages_ratelimited_async() > and then keep balance_dirty_pages_ratelimited_flags() as an internal > function. It is then more obvious at the external call sites what the call > is about (unlike the true/false argument). > I added a new function balance_dirty_pages_ratelimited_async() and made the function balance_dirty_pages_ratelimited_flags an internal function. > Honza > >> { >> struct inode *inode = mapping->host; >> struct backing_dev_info *bdi = inode_to_bdi(inode); >> struct bdi_writeback *wb = NULL; >> int ratelimit; >> + int ret = 0; >> int *p; >> >> if (!(bdi->capabilities & BDI_CAP_WRITEBACK)) >> - return; >> + return ret; >> >> if (inode_cgwb_enabled(inode)) >> wb = wb_get_create_current(bdi, GFP_KERNEL); >> @@ -1937,10 +1926,37 @@ void balance_dirty_pages_ratelimited(struct address_space *mapping) >> } >> preempt_enable(); >> >> - if (unlikely(current->nr_dirtied >= ratelimit)) >> - balance_dirty_pages(wb, current->nr_dirtied); >> + if (unlikely(current->nr_dirtied >= ratelimit)) { >> + if (is_async) { >> + struct bdp_ctx ctx = { BDP_CTX_INIT(ctx, wb) }; >> + >> + ret = _balance_dirty_pages(wb, current->nr_dirtied, &ctx); >> + if (ret) >> + ret = -EAGAIN; >> + } else { >> + balance_dirty_pages(wb, current->nr_dirtied); >> + } >> + } >> >> wb_put(wb); >> + return ret; >> +} >> + >> +/** >> + * balance_dirty_pages_ratelimited - balance dirty memory state >> + * @mapping: address_space which was dirtied >> + * >> + * Processes which are dirtying memory should call in here once for each page >> + * which was newly dirtied. The function will periodically check the system's >> + * dirty state and will initiate writeback if needed. >> + * >> + * Once we're over the dirty memory limit we decrease the ratelimiting >> + * by a lot, to prevent individual processes from overshooting the limit >> + * by (ratelimit_pages) each. >> + */ >> +void balance_dirty_pages_ratelimited(struct address_space *mapping) >> +{ >> + balance_dirty_pages_ratelimited_flags(mapping, false); >> } >> EXPORT_SYMBOL(balance_dirty_pages_ratelimited); >> >> -- >> 2.30.2 >>
diff --git a/include/linux/writeback.h b/include/linux/writeback.h index fec248ab1fec..d589804bb3be 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -373,6 +373,7 @@ unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh); void wb_update_bandwidth(struct bdi_writeback *wb); void balance_dirty_pages_ratelimited(struct address_space *mapping); +int balance_dirty_pages_ratelimited_flags(struct address_space *mapping, bool is_async); bool wb_over_bg_thresh(struct bdi_writeback *wb); typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc, diff --git a/mm/page-writeback.c b/mm/page-writeback.c index cbb74c0666c6..78f1326f3f20 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -1877,28 +1877,17 @@ static DEFINE_PER_CPU(int, bdp_ratelimits); */ DEFINE_PER_CPU(int, dirty_throttle_leaks) = 0; -/** - * balance_dirty_pages_ratelimited - balance dirty memory state - * @mapping: address_space which was dirtied - * - * Processes which are dirtying memory should call in here once for each page - * which was newly dirtied. The function will periodically check the system's - * dirty state and will initiate writeback if needed. - * - * Once we're over the dirty memory limit we decrease the ratelimiting - * by a lot, to prevent individual processes from overshooting the limit - * by (ratelimit_pages) each. - */ -void balance_dirty_pages_ratelimited(struct address_space *mapping) +int balance_dirty_pages_ratelimited_flags(struct address_space *mapping, bool is_async) { struct inode *inode = mapping->host; struct backing_dev_info *bdi = inode_to_bdi(inode); struct bdi_writeback *wb = NULL; int ratelimit; + int ret = 0; int *p; if (!(bdi->capabilities & BDI_CAP_WRITEBACK)) - return; + return ret; if (inode_cgwb_enabled(inode)) wb = wb_get_create_current(bdi, GFP_KERNEL); @@ -1937,10 +1926,37 @@ void balance_dirty_pages_ratelimited(struct address_space *mapping) } preempt_enable(); - if (unlikely(current->nr_dirtied >= ratelimit)) - balance_dirty_pages(wb, current->nr_dirtied); + if (unlikely(current->nr_dirtied >= ratelimit)) { + if (is_async) { + struct bdp_ctx ctx = { BDP_CTX_INIT(ctx, wb) }; + + ret = _balance_dirty_pages(wb, current->nr_dirtied, &ctx); + if (ret) + ret = -EAGAIN; + } else { + balance_dirty_pages(wb, current->nr_dirtied); + } + } wb_put(wb); + return ret; +} + +/** + * balance_dirty_pages_ratelimited - balance dirty memory state + * @mapping: address_space which was dirtied + * + * Processes which are dirtying memory should call in here once for each page + * which was newly dirtied. The function will periodically check the system's + * dirty state and will initiate writeback if needed. + * + * Once we're over the dirty memory limit we decrease the ratelimiting + * by a lot, to prevent individual processes from overshooting the limit + * by (ratelimit_pages) each. + */ +void balance_dirty_pages_ratelimited(struct address_space *mapping) +{ + balance_dirty_pages_ratelimited_flags(mapping, false); } EXPORT_SYMBOL(balance_dirty_pages_ratelimited);
This adds the function balance_dirty_pages_ratelimited_flags(). It adds the parameter is_async to balance_dirty_pages_ratelimited(). In case this is an async write, it will call _balance_diirty_pages() to determine if write throttling needs to be enabled. If write throttling is enabled, it retuns -EAGAIN, so the write request can be punted to the io-uring worker. The new function is changed to return the sleep time, so callers can observe if the write has been punted. For non-async writes the current behavior is maintained. Signed-off-by: Stefan Roesch <shr@fb.com> --- include/linux/writeback.h | 1 + mm/page-writeback.c | 48 ++++++++++++++++++++++++++------------- 2 files changed, 33 insertions(+), 16 deletions(-)