From: Al Viro <viro@zeniv.linux.org.uk>
To: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Eric Biggers <ebiggers@kernel.org>,
Matthew Wilcox <willy@infradead.org>,
"Theodore Y. Ts'o" <tytso@mit.edu>,
Jaegeuk Kim <jaegeuk@kernel.org>, Chao Yu <yuchao0@huawei.com>,
Tyler Hicks <tyhicks@canonical.com>,
linux-fsdevel@vger.kernel.org, ecryptfs@vger.kernel.org,
linux-fscrypt@vger.kernel.org,
linux-f2fs-devel@lists.sourceforge.net,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v5] fs: introduce is_dot_or_dotdot helper for cleanup
Date: Wed, 11 Dec 2019 04:47:23 +0000 [thread overview]
Message-ID: <20191211044723.GC4203@ZenIV.linux.org.uk> (raw)
In-Reply-To: <febbd7eb-5e53-6e7c-582d-5b224e441e37@loongson.cn>
On Wed, Dec 11, 2019 at 11:59:40AM +0800, Tiezhu Yang wrote:
> static inline bool is_dot_or_dotdot(const unsigned char *name, size_t len)
> {
> if (len == 1 && name[0] == '.')
> return true;
>
> if (len == 2 && name[0] == '.' && name[1] == '.')
> return true;
>
> return false;
> }
>
> Hi Matthew,
>
> How do you think? I think the performance influence is very small
> due to is_dot_or_dotdot() is a such short static inline function.
It's a very short inline function called on a very hot codepath.
Often.
I mean it - it's done literally for every pathname component of
every pathname passed to a syscall.
next prev parent reply other threads:[~2019-12-11 4:47 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-11 2:20 [PATCH v5] fs: introduce is_dot_or_dotdot helper for cleanup Tiezhu Yang
2019-12-11 2:48 ` Eric Biggers
2019-12-11 3:59 ` Tiezhu Yang
2019-12-11 4:47 ` Al Viro [this message]
2019-12-11 6:38 ` Tiezhu Yang
2019-12-11 7:17 ` Gao Xiang
2019-12-11 13:40 ` Matthew Wilcox
2019-12-11 14:41 ` Gao Xiang
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