| Message ID | 1676645312-13-3-git-send-email-ruansy.fnst@fujitsu.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm, pmem, xfs: Introduce MF_MEM_REMOVE for unbind | expand |
On Fri, Feb 17, 2023 at 02:48:31PM +0000, Shiyang Ruan wrote: > - invalidate_mapping_pages(inode->i_mapping, 0, -1); > - iput(toput_inode); > - toput_inode = inode; > - > - cond_resched(); > - spin_lock(&sb->s_inode_list_lock); > - } > - spin_unlock(&sb->s_inode_list_lock); > - iput(toput_inode); > + super_drop_pagecache(sb, invalidate_inode_pages); I thought I explained last time that you can do this with invalidate_mapping_pages() / invalidate_inode_pages2_range() ? Then you don't need to introduce invalidate_inode_pages(). > +void super_drop_pagecache(struct super_block *sb, > + int (*invalidator)(struct address_space *)) void super_drop_pagecache(struct super_block *sb, int (*invalidate)(struct address_space *, pgoff_t, pgoff_t)) > + invalidator(inode->i_mapping); invalidate(inode->i_mapping, 0, -1) ... then all the changes to mm/truncate.c and filemap.h go away.
在 2023/2/18 0:14, Matthew Wilcox 写道: > On Fri, Feb 17, 2023 at 02:48:31PM +0000, Shiyang Ruan wrote: >> - invalidate_mapping_pages(inode->i_mapping, 0, -1); >> - iput(toput_inode); >> - toput_inode = inode; >> - >> - cond_resched(); >> - spin_lock(&sb->s_inode_list_lock); >> - } >> - spin_unlock(&sb->s_inode_list_lock); >> - iput(toput_inode); >> + super_drop_pagecache(sb, invalidate_inode_pages); > > I thought I explained last time that you can do this with > invalidate_mapping_pages() / invalidate_inode_pages2_range() ? > Then you don't need to introduce invalidate_inode_pages(). > >> +void super_drop_pagecache(struct super_block *sb, >> + int (*invalidator)(struct address_space *)) > > void super_drop_pagecache(struct super_block *sb, > int (*invalidate)(struct address_space *, pgoff_t, pgoff_t)) > >> + invalidator(inode->i_mapping); > > invalidate(inode->i_mapping, 0, -1) > > ... then all the changes to mm/truncate.c and filemap.h go away. Yes, I tried as you suggested, but I found that they don't have same type of return value. int invalidate_inode_pages2_range(struct address_space *mapping, pgoff_t start, pgoff_t end); unsigned long invalidate_mapping_pages(struct address_space *mapping, pgoff_t start, pgoff_t end); -- Thanks, Ruan.
On Sat, Feb 18, 2023 at 09:16:43AM +0800, Shiyang Ruan wrote: > 在 2023/2/18 0:14, Matthew Wilcox 写道: > > On Fri, Feb 17, 2023 at 02:48:31PM +0000, Shiyang Ruan wrote: > > > - invalidate_mapping_pages(inode->i_mapping, 0, -1); > > > - iput(toput_inode); > > > - toput_inode = inode; > > > - > > > - cond_resched(); > > > - spin_lock(&sb->s_inode_list_lock); > > > - } > > > - spin_unlock(&sb->s_inode_list_lock); > > > - iput(toput_inode); > > > + super_drop_pagecache(sb, invalidate_inode_pages); > > > > I thought I explained last time that you can do this with > > invalidate_mapping_pages() / invalidate_inode_pages2_range() ? > > Then you don't need to introduce invalidate_inode_pages(). > > > > > +void super_drop_pagecache(struct super_block *sb, > > > + int (*invalidator)(struct address_space *)) > > > > void super_drop_pagecache(struct super_block *sb, > > int (*invalidate)(struct address_space *, pgoff_t, pgoff_t)) > > > > > + invalidator(inode->i_mapping); > > > > invalidate(inode->i_mapping, 0, -1) > > > > ... then all the changes to mm/truncate.c and filemap.h go away. > > Yes, I tried as you suggested, but I found that they don't have same type of > return value. > > int invalidate_inode_pages2_range(struct address_space *mapping, > pgoff_t start, pgoff_t end); > > unsigned long invalidate_mapping_pages(struct address_space *mapping, > pgoff_t start, pgoff_t end); Oh, that's annoying. Particularly annoying is that the return value for invalidate_mapping_pages() is used by fs/inode.c to account for the number of pages invalidate, and the return value for invalidate_inode_pages2_range() is used by several filesystems to know whether an error occurred. Hm. Shouldn't you be checking for an error from invalidate_inode_pages2_range()? Seems like it can return -EBUSY for DAX entries. With that in mind, the wrapper you actually want to exist is static int invalidate_inode_pages_range(struct address_space *mapping, pgoff_t start, pgoff_t end) { invalidate_mapping_pages(mapping, start, end); return 0; } Right?
在 2023/2/19 2:27, Matthew Wilcox 写道: > On Sat, Feb 18, 2023 at 09:16:43AM +0800, Shiyang Ruan wrote: >> 在 2023/2/18 0:14, Matthew Wilcox 写道: >>> On Fri, Feb 17, 2023 at 02:48:31PM +0000, Shiyang Ruan wrote: >>>> - invalidate_mapping_pages(inode->i_mapping, 0, -1); >>>> - iput(toput_inode); >>>> - toput_inode = inode; >>>> - >>>> - cond_resched(); >>>> - spin_lock(&sb->s_inode_list_lock); >>>> - } >>>> - spin_unlock(&sb->s_inode_list_lock); >>>> - iput(toput_inode); >>>> + super_drop_pagecache(sb, invalidate_inode_pages); >>> >>> I thought I explained last time that you can do this with >>> invalidate_mapping_pages() / invalidate_inode_pages2_range() ? >>> Then you don't need to introduce invalidate_inode_pages(). >>> >>>> +void super_drop_pagecache(struct super_block *sb, >>>> + int (*invalidator)(struct address_space *)) >>> >>> void super_drop_pagecache(struct super_block *sb, >>> int (*invalidate)(struct address_space *, pgoff_t, pgoff_t)) >>> >>>> + invalidator(inode->i_mapping); >>> >>> invalidate(inode->i_mapping, 0, -1) >>> >>> ... then all the changes to mm/truncate.c and filemap.h go away. >> >> Yes, I tried as you suggested, but I found that they don't have same type of >> return value. >> >> int invalidate_inode_pages2_range(struct address_space *mapping, >> pgoff_t start, pgoff_t end); >> >> unsigned long invalidate_mapping_pages(struct address_space *mapping, >> pgoff_t start, pgoff_t end); > > Oh, that's annoying. Particularly annoying is that the return value > for invalidate_mapping_pages() is used by fs/inode.c to account for > the number of pages invalidate, and the return value for > invalidate_inode_pages2_range() is used by several filesystems > to know whether an error occurred. > > Hm. Shouldn't you be checking for an error from > invalidate_inode_pages2_range()? Seems like it can return -EBUSY for > DAX entries. > > With that in mind, the wrapper you actually want to exist is > > static int invalidate_inode_pages_range(struct address_space *mapping, > pgoff_t start, pgoff_t end) > { > invalidate_mapping_pages(mapping, start, end); > return 0; > } > > Right? So, I should introduce this wrapper in fs/xfs/xfs_notify_failure.c because it is the only one who calls this wrapper. Ok, got it! -- Thanks, Ruan.
在 2023/2/20 17:39, Shiyang Ruan 写道: > > > 在 2023/2/19 2:27, Matthew Wilcox 写道: >> On Sat, Feb 18, 2023 at 09:16:43AM +0800, Shiyang Ruan wrote: >>> 在 2023/2/18 0:14, Matthew Wilcox 写道: >>>> On Fri, Feb 17, 2023 at 02:48:31PM +0000, Shiyang Ruan wrote: >>>>> - invalidate_mapping_pages(inode->i_mapping, 0, -1); >>>>> - iput(toput_inode); >>>>> - toput_inode = inode; >>>>> - >>>>> - cond_resched(); >>>>> - spin_lock(&sb->s_inode_list_lock); >>>>> - } >>>>> - spin_unlock(&sb->s_inode_list_lock); >>>>> - iput(toput_inode); >>>>> + super_drop_pagecache(sb, invalidate_inode_pages); >>>> >>>> I thought I explained last time that you can do this with >>>> invalidate_mapping_pages() / invalidate_inode_pages2_range() ? >>>> Then you don't need to introduce invalidate_inode_pages(). >>>> >>>>> +void super_drop_pagecache(struct super_block *sb, >>>>> + int (*invalidator)(struct address_space *)) >>>> >>>> void super_drop_pagecache(struct super_block *sb, >>>> int (*invalidate)(struct address_space *, pgoff_t, pgoff_t)) >>>> >>>>> + invalidator(inode->i_mapping); >>>> >>>> invalidate(inode->i_mapping, 0, -1) >>>> >>>> ... then all the changes to mm/truncate.c and filemap.h go away. >>> >>> Yes, I tried as you suggested, but I found that they don't have same >>> type of >>> return value. >>> >>> int invalidate_inode_pages2_range(struct address_space *mapping, >>> pgoff_t start, pgoff_t end); >>> >>> unsigned long invalidate_mapping_pages(struct address_space *mapping, >>> pgoff_t start, pgoff_t end); >> >> Oh, that's annoying. Particularly annoying is that the return value >> for invalidate_mapping_pages() is used by fs/inode.c to account for >> the number of pages invalidate, and the return value for >> invalidate_inode_pages2_range() is used by several filesystems >> to know whether an error occurred. >> >> Hm. Shouldn't you be checking for an error from >> invalidate_inode_pages2_range()? Seems like it can return -EBUSY for >> DAX entries. >> >> With that in mind, the wrapper you actually want to exist is >> >> static int invalidate_inode_pages_range(struct address_space *mapping, >> pgoff_t start, pgoff_t end) >> { >> invalidate_mapping_pages(mapping, start, end); >> return 0; >> } >> >> Right? > > So, I should introduce this wrapper in fs/xfs/xfs_notify_failure.c Ahh... It's not fs/xfs/xfs_notify_failure.c, should be fs/drop_caches.c. > because it is the only one who calls this wrapper. Ok, got it! > > > -- > Thanks, > Ruan.
On Fri, Feb 17, 2023 at 02:48:31PM +0000, Shiyang Ruan wrote: > xfs_notify_failure.c requires a method to invalidate all dax mappings. > drop_pagecache_sb() can do this but it is a static function and only > build with CONFIG_SYSCTL. Now, move its implementation into super.c and > call it super_drop_pagecache(). Use its second argument as invalidator > so that we can choose which invalidate method to use. > > Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> I got no repsonse last time, so I'll just post a link to the concerns I stated about this: https://lore.kernel.org/linux-xfs/20230205215000.GT360264@dread.disaster.area/ -Dave.
在 2023/2/21 5:25, Dave Chinner 写道: > On Fri, Feb 17, 2023 at 02:48:31PM +0000, Shiyang Ruan wrote: >> xfs_notify_failure.c requires a method to invalidate all dax mappings. >> drop_pagecache_sb() can do this but it is a static function and only >> build with CONFIG_SYSCTL. Now, move its implementation into super.c and >> call it super_drop_pagecache(). Use its second argument as invalidator >> so that we can choose which invalidate method to use. >> >> Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> > > I got no repsonse last time, so I'll just post a link to the > concerns I stated about this: > > https://lore.kernel.org/linux-xfs/20230205215000.GT360264@dread.disaster.area/ Please see patch 3. I changed the code: freeze the fs, then drop its caches. -- Thanks, Ruan. > > -Dave.
On Tue, Feb 21, 2023 at 09:57:52AM +0800, Shiyang Ruan wrote: > > > 在 2023/2/21 5:25, Dave Chinner 写道: > > On Fri, Feb 17, 2023 at 02:48:31PM +0000, Shiyang Ruan wrote: > > > xfs_notify_failure.c requires a method to invalidate all dax mappings. > > > drop_pagecache_sb() can do this but it is a static function and only > > > build with CONFIG_SYSCTL. Now, move its implementation into super.c and > > > call it super_drop_pagecache(). Use its second argument as invalidator > > > so that we can choose which invalidate method to use. > > > > > > Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> > > > > I got no repsonse last time, so I'll just post a link to the > > concerns I stated about this: > > > > https://lore.kernel.org/linux-xfs/20230205215000.GT360264@dread.disaster.area/ > > Please see patch 3. I changed the code: freeze the fs, then drop its > caches. Neither the patch nor the cover letter have a changelog in them that mention you changed anything. Please, at least, keep a change log in the cover letter so that people know what has changed from version to version without having to look at every patch and line of code again. -Dave.
diff --git a/fs/drop_caches.c b/fs/drop_caches.c index e619c31b6bd9..f88ce339b635 100644 --- a/fs/drop_caches.c +++ b/fs/drop_caches.c @@ -17,34 +17,7 @@ int sysctl_drop_caches; static void drop_pagecache_sb(struct super_block *sb, void *unused) { - struct inode *inode, *toput_inode = NULL; - - spin_lock(&sb->s_inode_list_lock); - list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { - spin_lock(&inode->i_lock); - /* - * We must skip inodes in unusual state. We may also skip - * inodes without pages but we deliberately won't in case - * we need to reschedule to avoid softlockups. - */ - if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) || - (mapping_empty(inode->i_mapping) && !need_resched())) { - spin_unlock(&inode->i_lock); - continue; - } - __iget(inode); - spin_unlock(&inode->i_lock); - spin_unlock(&sb->s_inode_list_lock); - - invalidate_mapping_pages(inode->i_mapping, 0, -1); - iput(toput_inode); - toput_inode = inode; - - cond_resched(); - spin_lock(&sb->s_inode_list_lock); - } - spin_unlock(&sb->s_inode_list_lock); - iput(toput_inode); + super_drop_pagecache(sb, invalidate_inode_pages); } int drop_caches_sysctl_handler(struct ctl_table *table, int write, diff --git a/fs/super.c b/fs/super.c index 12c08cb20405..a403243b5513 100644 --- a/fs/super.c +++ b/fs/super.c @@ -36,6 +36,7 @@ #include <linux/lockdep.h> #include <linux/user_namespace.h> #include <linux/fs_context.h> +#include <linux/pagemap.h> #include <uapi/linux/mount.h> #include "internal.h" @@ -678,6 +679,48 @@ void drop_super_exclusive(struct super_block *sb) } EXPORT_SYMBOL(drop_super_exclusive); +/** + * super_drop_pagecache - drop all page caches of a filesystem + * @sb: superblock to invalidate + * @arg: invalidate method, such as invalidate_inode_pages(), + * invalidate_inode_pages2() + * + * Scans the inodes of a filesystem, drop all page caches. + */ +void super_drop_pagecache(struct super_block *sb, + int (*invalidator)(struct address_space *)) +{ + struct inode *inode, *toput_inode = NULL; + + spin_lock(&sb->s_inode_list_lock); + list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { + spin_lock(&inode->i_lock); + /* + * We must skip inodes in unusual state. We may also skip + * inodes without pages but we deliberately won't in case + * we need to reschedule to avoid softlockups. + */ + if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) || + (mapping_empty(inode->i_mapping) && !need_resched())) { + spin_unlock(&inode->i_lock); + continue; + } + __iget(inode); + spin_unlock(&inode->i_lock); + spin_unlock(&sb->s_inode_list_lock); + + invalidator(inode->i_mapping); + iput(toput_inode); + toput_inode = inode; + + cond_resched(); + spin_lock(&sb->s_inode_list_lock); + } + spin_unlock(&sb->s_inode_list_lock); + iput(toput_inode); +} +EXPORT_SYMBOL(super_drop_pagecache); + static void __iterate_supers(void (*f)(struct super_block *)) { struct super_block *sb, *p = NULL; diff --git a/include/linux/fs.h b/include/linux/fs.h index c1769a2c5d70..fdcaa9bf85dd 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3308,6 +3308,8 @@ extern struct super_block *get_super(struct block_device *); extern struct super_block *get_active_super(struct block_device *bdev); extern void drop_super(struct super_block *sb); extern void drop_super_exclusive(struct super_block *sb); +void super_drop_pagecache(struct super_block *sb, + int (*invalidator)(struct address_space *)); extern void iterate_supers(void (*)(struct super_block *, void *), void *); extern void iterate_supers_type(struct file_system_type *, void (*)(struct super_block *, void *), void *); diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 29e1f9e76eb6..d0a180268baa 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -27,6 +27,7 @@ static inline void invalidate_remote_inode(struct inode *inode) S_ISLNK(inode->i_mode)) invalidate_mapping_pages(inode->i_mapping, 0, -1); } +int invalidate_inode_pages(struct address_space *mapping); int invalidate_inode_pages2(struct address_space *mapping); int invalidate_inode_pages2_range(struct address_space *mapping, pgoff_t start, pgoff_t end); diff --git a/mm/truncate.c b/mm/truncate.c index 7b4ea4c4a46b..131f2ab2d566 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -540,12 +540,13 @@ unsigned long invalidate_mapping_pagevec(struct address_space *mapping, } /** - * invalidate_mapping_pages - Invalidate all clean, unlocked cache of one inode + * invalidate_mapping_pages - Invalidate range of clean, unlocked cache of one + * inode * @mapping: the address_space which holds the cache to invalidate * @start: the offset 'from' which to invalidate * @end: the offset 'to' which to invalidate (inclusive) * - * This function removes pages that are clean, unmapped and unlocked, + * This function removes range of pages that are clean, unmapped and unlocked, * as well as shadow entries. It will not block on IO activity. * * If you want to remove all the pages of one inode, regardless of @@ -560,6 +561,21 @@ unsigned long invalidate_mapping_pages(struct address_space *mapping, } EXPORT_SYMBOL(invalidate_mapping_pages); +/** + * invalidate_inode_pages - Invalidate all clean, unlocked cache of one inode + * @mapping: the address_space which holds the cache to invalidate + * + * This function removes all pages that are clean, unmapped and unlocked, + * as well as shadow entries. It will not block on IO activity. + */ +int invalidate_inode_pages(struct address_space *mapping) +{ + invalidate_mapping_pages(mapping, 0, -1); + + return 0; +} +EXPORT_SYMBOL(invalidate_inode_pages); + /* * This is like invalidate_inode_page(), except it ignores the page's * refcount. We do this because invalidate_inode_pages2() needs stronger
xfs_notify_failure.c requires a method to invalidate all dax mappings. drop_pagecache_sb() can do this but it is a static function and only build with CONFIG_SYSCTL. Now, move its implementation into super.c and call it super_drop_pagecache(). Use its second argument as invalidator so that we can choose which invalidate method to use. Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> --- fs/drop_caches.c | 29 +-------------------------- fs/super.c | 43 +++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 2 ++ include/linux/pagemap.h | 1 + mm/truncate.c | 20 +++++++++++++++++-- 5 files changed, 65 insertions(+), 30 deletions(-)