| Message ID | 20230228085002.2592473-2-yosryahmed@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Ignore non-LRU-based reclaim in memcg reclaim | expand |
+Yu Zhao On Tue, Feb 28, 2023 at 12:50 AM Yosry Ahmed <yosryahmed@google.com> wrote: > > During reclaim, we keep track of pages reclaimed from other means than > LRU-based reclaim through scan_control->reclaim_state->reclaimed_slab, > which we stash a pointer to in current task_struct. > > However, we keep track of more than just reclaimed slab pages through > this. We also use it for clean file pages dropped through pruned inodes, > and xfs buffer pages freed. Rename reclaimed_slab to reclaimed, and add > a helper function that wraps updating it through current. > > Signed-off-by: Yosry Ahmed <yosryahmed@google.com> > --- > fs/inode.c | 3 +-- > fs/xfs/xfs_buf.c | 3 +-- > include/linux/swap.h | 5 ++++- > mm/slab.c | 3 +-- > mm/slob.c | 6 ++---- > mm/slub.c | 5 ++--- > mm/vmscan.c | 31 +++++++++++++++++++++++++------ > 7 files changed, 36 insertions(+), 20 deletions(-) > > diff --git a/fs/inode.c b/fs/inode.c > index 4558dc2f1355..1022d8ac7205 100644 > --- a/fs/inode.c > +++ b/fs/inode.c > @@ -864,8 +864,7 @@ static enum lru_status inode_lru_isolate(struct list_head *item, > __count_vm_events(KSWAPD_INODESTEAL, reap); > else > __count_vm_events(PGINODESTEAL, reap); > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += reap; > + report_freed_pages(reap); > } > iput(inode); > spin_lock(lru_lock); > diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c > index 54c774af6e1c..060079f1e966 100644 > --- a/fs/xfs/xfs_buf.c > +++ b/fs/xfs/xfs_buf.c > @@ -286,8 +286,7 @@ xfs_buf_free_pages( > if (bp->b_pages[i]) > __free_page(bp->b_pages[i]); > } > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += bp->b_page_count; > + report_freed_pages(bp->b_page_count); > > if (bp->b_pages != bp->b_page_array) > kmem_free(bp->b_pages); > diff --git a/include/linux/swap.h b/include/linux/swap.h > index 209a425739a9..525f0ae442f9 100644 > --- a/include/linux/swap.h > +++ b/include/linux/swap.h > @@ -153,13 +153,16 @@ union swap_header { > * memory reclaim > */ > struct reclaim_state { > - unsigned long reclaimed_slab; > + /* pages reclaimed outside of LRU-based reclaim */ > + unsigned long reclaimed; > #ifdef CONFIG_LRU_GEN > /* per-thread mm walk data */ > struct lru_gen_mm_walk *mm_walk; > #endif > }; > > +void report_freed_pages(unsigned long pages); > + > #ifdef __KERNEL__ > > struct address_space; > diff --git a/mm/slab.c b/mm/slab.c > index dabc2a671fc6..325634416aab 100644 > --- a/mm/slab.c > +++ b/mm/slab.c > @@ -1392,8 +1392,7 @@ static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab) > smp_wmb(); > __folio_clear_slab(folio); > > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += 1 << order; > + report_freed_pages(1 << order); > unaccount_slab(slab, order, cachep); > __free_pages(&folio->page, order); > } > diff --git a/mm/slob.c b/mm/slob.c > index fe567fcfa3a3..71ee00e9dd46 100644 > --- a/mm/slob.c > +++ b/mm/slob.c > @@ -61,7 +61,7 @@ > #include <linux/slab.h> > > #include <linux/mm.h> > -#include <linux/swap.h> /* struct reclaim_state */ > +#include <linux/swap.h> /* report_freed_pages() */ > #include <linux/cache.h> > #include <linux/init.h> > #include <linux/export.h> > @@ -211,9 +211,7 @@ static void slob_free_pages(void *b, int order) > { > struct page *sp = virt_to_page(b); > > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += 1 << order; > - > + report_freed_pages(1 << order); > mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > -(PAGE_SIZE << order)); > __free_pages(sp, order); > diff --git a/mm/slub.c b/mm/slub.c > index 39327e98fce3..165319bf11f1 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -11,7 +11,7 @@ > */ > > #include <linux/mm.h> > -#include <linux/swap.h> /* struct reclaim_state */ > +#include <linux/swap.h> /* report_freed_pages() */ > #include <linux/module.h> > #include <linux/bit_spinlock.h> > #include <linux/interrupt.h> > @@ -2063,8 +2063,7 @@ static void __free_slab(struct kmem_cache *s, struct slab *slab) > /* Make the mapping reset visible before clearing the flag */ > smp_wmb(); > __folio_clear_slab(folio); > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += pages; > + report_freed_pages(pages); > unaccount_slab(slab, order, s); > __free_pages(&folio->page, order); > } > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 9c1c5e8b24b8..8846531e85a4 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -200,6 +200,29 @@ static void set_task_reclaim_state(struct task_struct *task, > task->reclaim_state = rs; > } > > +/* > + * reclaim_report_freed_pages: report pages freed outside of LRU-based reclaim > + * @pages: number of pages freed > + * > + * If the current process is undergoing a reclaim operation, > + * increment the number of reclaimed pages by @pages. > + */ > +void report_freed_pages(unsigned long pages) > +{ > + if (current->reclaim_state) > + current->reclaim_state->reclaimed += pages; > +} > +EXPORT_SYMBOL(report_freed_pages); > + > +static void add_non_vmscan_reclaimed(struct scan_control *sc, > + struct reclaim_state *rs) > +{ > + if (rs) { > + sc->nr_reclaimed += rs->reclaimed; > + rs->reclaimed = 0; > + } > +} > + > LIST_HEAD(shrinker_list); > DECLARE_RWSEM(shrinker_rwsem); > > @@ -5346,8 +5369,7 @@ static int shrink_one(struct lruvec *lruvec, struct scan_control *sc) > vmpressure(sc->gfp_mask, memcg, false, sc->nr_scanned - scanned, > sc->nr_reclaimed - reclaimed); > > - sc->nr_reclaimed += current->reclaim_state->reclaimed_slab; > - current->reclaim_state->reclaimed_slab = 0; > + add_non_vmscan_reclaimed(sc, current->reclaim_state); > > return success ? MEMCG_LRU_YOUNG : 0; > } > @@ -6472,10 +6494,7 @@ static void shrink_node(pg_data_t *pgdat, struct scan_control *sc) > > shrink_node_memcgs(pgdat, sc); > > - if (reclaim_state) { > - sc->nr_reclaimed += reclaim_state->reclaimed_slab; > - reclaim_state->reclaimed_slab = 0; > - } > + add_non_vmscan_reclaimed(sc, reclaim_state); > > /* Record the subtree's reclaim efficiency */ > if (!sc->proactive) > -- > 2.39.2.722.g9855ee24e9-goog >
diff --git a/fs/inode.c b/fs/inode.c index 4558dc2f1355..1022d8ac7205 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -864,8 +864,7 @@ static enum lru_status inode_lru_isolate(struct list_head *item, __count_vm_events(KSWAPD_INODESTEAL, reap); else __count_vm_events(PGINODESTEAL, reap); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += reap; + report_freed_pages(reap); } iput(inode); spin_lock(lru_lock); diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index 54c774af6e1c..060079f1e966 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -286,8 +286,7 @@ xfs_buf_free_pages( if (bp->b_pages[i]) __free_page(bp->b_pages[i]); } - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += bp->b_page_count; + report_freed_pages(bp->b_page_count); if (bp->b_pages != bp->b_page_array) kmem_free(bp->b_pages); diff --git a/include/linux/swap.h b/include/linux/swap.h index 209a425739a9..525f0ae442f9 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -153,13 +153,16 @@ union swap_header { * memory reclaim */ struct reclaim_state { - unsigned long reclaimed_slab; + /* pages reclaimed outside of LRU-based reclaim */ + unsigned long reclaimed; #ifdef CONFIG_LRU_GEN /* per-thread mm walk data */ struct lru_gen_mm_walk *mm_walk; #endif }; +void report_freed_pages(unsigned long pages); + #ifdef __KERNEL__ struct address_space; diff --git a/mm/slab.c b/mm/slab.c index dabc2a671fc6..325634416aab 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1392,8 +1392,7 @@ static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab) smp_wmb(); __folio_clear_slab(folio); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += 1 << order; + report_freed_pages(1 << order); unaccount_slab(slab, order, cachep); __free_pages(&folio->page, order); } diff --git a/mm/slob.c b/mm/slob.c index fe567fcfa3a3..71ee00e9dd46 100644 --- a/mm/slob.c +++ b/mm/slob.c @@ -61,7 +61,7 @@ #include <linux/slab.h> #include <linux/mm.h> -#include <linux/swap.h> /* struct reclaim_state */ +#include <linux/swap.h> /* report_freed_pages() */ #include <linux/cache.h> #include <linux/init.h> #include <linux/export.h> @@ -211,9 +211,7 @@ static void slob_free_pages(void *b, int order) { struct page *sp = virt_to_page(b); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += 1 << order; - + report_freed_pages(1 << order); mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, -(PAGE_SIZE << order)); __free_pages(sp, order); diff --git a/mm/slub.c b/mm/slub.c index 39327e98fce3..165319bf11f1 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -11,7 +11,7 @@ */ #include <linux/mm.h> -#include <linux/swap.h> /* struct reclaim_state */ +#include <linux/swap.h> /* report_freed_pages() */ #include <linux/module.h> #include <linux/bit_spinlock.h> #include <linux/interrupt.h> @@ -2063,8 +2063,7 @@ static void __free_slab(struct kmem_cache *s, struct slab *slab) /* Make the mapping reset visible before clearing the flag */ smp_wmb(); __folio_clear_slab(folio); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += pages; + report_freed_pages(pages); unaccount_slab(slab, order, s); __free_pages(&folio->page, order); } diff --git a/mm/vmscan.c b/mm/vmscan.c index 9c1c5e8b24b8..8846531e85a4 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -200,6 +200,29 @@ static void set_task_reclaim_state(struct task_struct *task, task->reclaim_state = rs; } +/* + * reclaim_report_freed_pages: report pages freed outside of LRU-based reclaim + * @pages: number of pages freed + * + * If the current process is undergoing a reclaim operation, + * increment the number of reclaimed pages by @pages. + */ +void report_freed_pages(unsigned long pages) +{ + if (current->reclaim_state) + current->reclaim_state->reclaimed += pages; +} +EXPORT_SYMBOL(report_freed_pages); + +static void add_non_vmscan_reclaimed(struct scan_control *sc, + struct reclaim_state *rs) +{ + if (rs) { + sc->nr_reclaimed += rs->reclaimed; + rs->reclaimed = 0; + } +} + LIST_HEAD(shrinker_list); DECLARE_RWSEM(shrinker_rwsem); @@ -5346,8 +5369,7 @@ static int shrink_one(struct lruvec *lruvec, struct scan_control *sc) vmpressure(sc->gfp_mask, memcg, false, sc->nr_scanned - scanned, sc->nr_reclaimed - reclaimed); - sc->nr_reclaimed += current->reclaim_state->reclaimed_slab; - current->reclaim_state->reclaimed_slab = 0; + add_non_vmscan_reclaimed(sc, current->reclaim_state); return success ? MEMCG_LRU_YOUNG : 0; } @@ -6472,10 +6494,7 @@ static void shrink_node(pg_data_t *pgdat, struct scan_control *sc) shrink_node_memcgs(pgdat, sc); - if (reclaim_state) { - sc->nr_reclaimed += reclaim_state->reclaimed_slab; - reclaim_state->reclaimed_slab = 0; - } + add_non_vmscan_reclaimed(sc, reclaim_state); /* Record the subtree's reclaim efficiency */ if (!sc->proactive)
During reclaim, we keep track of pages reclaimed from other means than LRU-based reclaim through scan_control->reclaim_state->reclaimed_slab, which we stash a pointer to in current task_struct. However, we keep track of more than just reclaimed slab pages through this. We also use it for clean file pages dropped through pruned inodes, and xfs buffer pages freed. Rename reclaimed_slab to reclaimed, and add a helper function that wraps updating it through current. Signed-off-by: Yosry Ahmed <yosryahmed@google.com> --- fs/inode.c | 3 +-- fs/xfs/xfs_buf.c | 3 +-- include/linux/swap.h | 5 ++++- mm/slab.c | 3 +-- mm/slob.c | 6 ++---- mm/slub.c | 5 ++--- mm/vmscan.c | 31 +++++++++++++++++++++++++------ 7 files changed, 36 insertions(+), 20 deletions(-)