On 2020/5/6 23:05, Jaegeuk Kim wrote: > On 05/06, Chao Yu wrote: >> In f2fs_try_to_free_nids(), .nid_list_lock spinlock critical region will >> increase as expected shrink number increase, to avoid spining other CPUs >> for long time, it's better to implement like extent cache and nats >> shrinker. >> >> Signed-off-by: Chao Yu <yuch...@huawei.com> >> --- >> v2: >> - fix unlock wrong spinlock. >> fs/f2fs/node.c | 15 +++++++++++---- >> 1 file changed, 11 insertions(+), 4 deletions(-) >> >> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c >> index 4da0d8713df5..ad0b14f4dab8 100644 >> --- a/fs/f2fs/node.c >> +++ b/fs/f2fs/node.c >> @@ -2488,7 +2488,6 @@ void f2fs_alloc_nid_failed(struct f2fs_sb_info *sbi, >> nid_t nid) >> int f2fs_try_to_free_nids(struct f2fs_sb_info *sbi, int nr_shrink) >> { >> struct f2fs_nm_info *nm_i = NM_I(sbi); >> - struct free_nid *i, *next; >> int nr = nr_shrink; >> >> if (nm_i->nid_cnt[FREE_NID] <= MAX_FREE_NIDS) >> @@ -2498,14 +2497,22 @@ int f2fs_try_to_free_nids(struct f2fs_sb_info *sbi, >> int nr_shrink) >> return 0; >> >> spin_lock(&nm_i->nid_list_lock); >> - list_for_each_entry_safe(i, next, &nm_i->free_nid_list, list) { >> - if (nr_shrink <= 0 || >> - nm_i->nid_cnt[FREE_NID] <= MAX_FREE_NIDS) >> + while (nr_shrink) { >> + struct free_nid *i; >> + >> + if (nm_i->nid_cnt[FREE_NID] <= MAX_FREE_NIDS) >> break; >> >> + i = list_first_entry(&nm_i->free_nid_list, >> + struct free_nid, list); >> + list_del(&i->list); >> + spin_unlock(&nm_i->nid_list_lock); >> + >> __remove_free_nid(sbi, i, FREE_NID); > > __remove_free_nid() will do list_del again. btw, how about just splitting out
Oh, my bad. How about moving __remove_free_nid into .nid_list_lock coverage? > given nr_shrink into multiple trials? Like this? while (shrink) { batch = DEFAULT_BATCH_NUMBER; // 16 spinlock(); list_for_each_entry_safe() { if (!shrink || !batch) break; remove_item_from_list; shrink--; batch--; } spin_unlock(); } Thanks, > >> kmem_cache_free(free_nid_slab, i); >> nr_shrink--; >> + >> + spin_lock(&nm_i->nid_list_lock); >> } >> spin_unlock(&nm_i->nid_list_lock); >> mutex_unlock(&nm_i->build_lock); >> -- >> 2.18.0.rc1 > . > _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel