2023-06-01 01:42:32

by Wu Bo

Subject: [PATCH v3 1/1] f2fs: fix args passed to trace_f2fs_lookup_end

The NULL return of 'd_splice_alias' dosen't mean error. Thus the
successful case will also return NULL, which makes the tracepoint always
print 'err=-ENOENT'.

And the different cases of 'new' & 'err' are list as following:
1) dentry exists: err(0) with new(NULL) --> dentry, err=0
2) dentry exists: err(0) with new(VALID) --> new, err=0
3) dentry exists: err(0) with new(ERR) --> dentry, err=ERR
4) no dentry exists: err(-ENOENT) with new(NULL) --> dentry, err=-ENOENT
5) no dentry exists: err(-ENOENT) with new(VALID) --> new, err=-ENOENT
6) no dentry exists: err(-ENOENT) with new(ERR) --> dentry, err=ERR

Signed-off-by: Wu Bo <[email protected]>
---
fs/f2fs/namei.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 77a71276ecb1..3e35eb7dbb8f 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -576,8 +576,8 @@ static struct dentry *f2fs_lookup(struct inode *dir, struct dentry *dentry,
}
#endif
new = d_splice_alias(inode, dentry);
- err = PTR_ERR_OR_ZERO(new);
- trace_f2fs_lookup_end(dir, dentry, ino, !new ? -ENOENT : err);
+ trace_f2fs_lookup_end(dir, !IS_ERR_OR_NULL(new) ? new : dentry,
+ ino, IS_ERR(new) ? PTR_ERR(new) : err);
return new;
out_iput:
iput(inode);
--
2.35.3

2023-06-06 01:29:40

by Chao Yu

Subject: Re: [PATCH v3 1/1] f2fs: fix args passed to trace_f2fs_lookup_end

On 2023/6/1 9:37, Wu Bo wrote:
> The NULL return of 'd_splice_alias' dosen't mean error. Thus the
> successful case will also return NULL, which makes the tracepoint always
> print 'err=-ENOENT'.
>
> And the different cases of 'new' & 'err' are list as following:
> 1) dentry exists: err(0) with new(NULL) --> dentry, err=0
> 2) dentry exists: err(0) with new(VALID) --> new, err=0
> 3) dentry exists: err(0) with new(ERR) --> dentry, err=ERR
> 4) no dentry exists: err(-ENOENT) with new(NULL) --> dentry, err=-ENOENT
> 5) no dentry exists: err(-ENOENT) with new(VALID) --> new, err=-ENOENT
> 6) no dentry exists: err(-ENOENT) with new(ERR) --> dentry, err=ERR
>
> Signed-off-by: Wu Bo <[email protected]>

Reviewed-by: Chao Yu <[email protected]>

Thanks,

2023-06-07 18:11:43

by patchwork-bot+f2fs

Subject: Re: [f2fs-dev] [PATCH v3 1/1] f2fs: fix args passed to trace_f2fs_lookup_end

Hello:

This patch was applied to jaegeuk/f2fs.git (dev)
by Jaegeuk Kim <[email protected]>:

On Thu, 1 Jun 2023 09:37:59 +0800 you wrote:
> The NULL return of 'd_splice_alias' dosen't mean error. Thus the
> successful case will also return NULL, which makes the tracepoint always
> print 'err=-ENOENT'.
>
> And the different cases of 'new' & 'err' are list as following:
> 1) dentry exists: err(0) with new(NULL) --> dentry, err=0
> 2) dentry exists: err(0) with new(VALID) --> new, err=0
> 3) dentry exists: err(0) with new(ERR) --> dentry, err=ERR
> 4) no dentry exists: err(-ENOENT) with new(NULL) --> dentry, err=-ENOENT
> 5) no dentry exists: err(-ENOENT) with new(VALID) --> new, err=-ENOENT
> 6) no dentry exists: err(-ENOENT) with new(ERR) --> dentry, err=ERR
>
> [...]

Here is the summary with links:
- [f2fs-dev,v3,1/1] f2fs: fix args passed to trace_f2fs_lookup_end
https://git.kernel.org/jaegeuk/f2fs/c/fddd7d0466ae

You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html