Re: [f2fs-dev] [RFC PATCH] f2fs: don't set SBI_QUOTA_NEED_REPAIR flag if receive SIGKILL

From: Chao Yu
Date: Wed Sep 11 2024 - 03:12:36 EST


On 2024/9/4 11:49, Chao Yu via Linux-f2fs-devel wrote:
On 2024/9/3 14:06, wangzijie wrote:
From: Chao Yu via Linux-f2fs-devel <linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx>

On 2024/8/27 14:22, wangzijie wrote:
Thread A
-dquot_initialize
  -dqget
   -f2fs_dquot_acquire
    -v2_read_dquot
     -qtree_read_dquot
      -find_tree_dqentry
       -f2fs_quota_read
        -read_cache_page_gfp
         -do_read_cache_folio
          -fiemap_read_folio
           -folio_wait_locked_killable
            -receive SIGKILL : return -EINTR
        -set SBI_QUOTA_NEED_REPAIR
    -set SBI_QUOTA_NEED_REPAIR

When calling read_cache_page_gfp in quota read, thread may receive SIGKILL and
set SBI_QUOTA_NEED_REPAIR, should we set SBI_QUOTA_NEED_REPAIR in this error path?

f2fs_quota_read() can be called in a lot of contexts, can we just ignore -EINTR
for f2fs_dquot_initialize() case?

Thanks,

Yes, in many contexts f2fs_quota_read() can be called and may return -EINTR, we need to ignore this errno for more cases. If we need to do so, I will check it and resend patch.
Or do you have other suggestions to avoid unnecessary SBI_QUOTA_NEED_REPAIR flag set?

How about this?

---
 fs/f2fs/f2fs.h  |  1 +
 fs/f2fs/inode.c |  3 +--
 fs/f2fs/super.c | 17 +++++++++++++----
 3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index dfed1974eda5..a1704a19dfe9 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -810,6 +810,7 @@ enum {
     FI_ATOMIC_DIRTIED,    /* indicate atomic file is dirtied */
     FI_ATOMIC_REPLACE,    /* indicate atomic replace */
     FI_OPENED_FILE,        /* indicate file has been opened */
+    FI_INIT_DQUOT,        /* indicate it's initializing dquot */
     FI_MAX,            /* max flag, never be used */
 };

diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 008f01348afa..b1dbaeda306f 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -827,8 +827,7 @@ void f2fs_evict_inode(struct inode *inode)

     err = f2fs_dquot_initialize(inode);
     if (err) {
-        if (err != -EINTR)
-            set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
+        set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
         err = 0;
     }

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 8e29aba4b7a4..e774bdf875b2 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -2644,8 +2644,11 @@ static ssize_t f2fs_quota_read(struct super_block *sb, int type, char *data,
             if (PTR_ERR(page) == -ENOMEM) {
                 memalloc_retry_wait(GFP_NOFS);
                 goto repeat;
-            } else if (PTR_ERR(page) != -EINTR)
-                set_sbi_flag(F2FS_SB(sb), SBI_QUOTA_NEED_REPAIR);
+            } else if (PTR_ERR(page) == -EINTR &&
+                is_inode_flag_set(inode, FI_INIT_DQUOT)) {

Current inode is quota inode, it's not the same inode we tagged
w/ FI_INIT_DQUOT, so please ignore this diff...

Thanks,

+                return PTR_ERR(page);
+            }
+            set_sbi_flag(F2FS_SB(sb), SBI_QUOTA_NEED_REPAIR);
             return PTR_ERR(page);
         }

@@ -2721,10 +2724,16 @@ static ssize_t f2fs_quota_write(struct super_block *sb, int type,

 int f2fs_dquot_initialize(struct inode *inode)
 {
+    int ret;
+
     if (time_to_inject(F2FS_I_SB(inode), FAULT_DQUOT_INIT))
         return -ESRCH;

-    return dquot_initialize(inode);
+    set_inode_flag(inode, FI_INIT_DQUOT);
+    ret = dquot_initialize(inode);
+    clear_inode_flag(inode, FI_INIT_DQUOT);
+
+    return ret;
 }

 static struct dquot __rcu **f2fs_get_dquots(struct inode *inode)
@@ -3064,7 +3073,7 @@ static int f2fs_dquot_acquire(struct dquot *dquot)

     f2fs_down_read(&sbi->quota_sem);
     ret = dquot_acquire(dquot);
-    if (ret < 0 && ret != -EINTR)
+    if (ret < 0)
         set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
     f2fs_up_read(&sbi->quota_sem);
     return ret;