From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@kernel.org>,
Sebastian Siewior <bigeasy@linutronix.de>,
Anna-Maria Gleixner <anna-maria@linutronix.de>,
Steven Rostedt <rostedt@goodmis.org>,
Julia Cartwright <julia@ni.com>,
linux-ext4@vger.kernel.org, "Theodore Tso" <tytso@mit.edu>,
Jan Kara <jack@suse.com>, Jan Kara <jack@suse.cz>,
Matthew Wilcox <willy@infradead.org>,
Alexander Viro <viro@zeniv.linux.org.uk>,
linux-fsdevel@vger.kernel.org, Mark Fasheh <mark@fasheh.com>,
Joseph Qi <joseph.qi@linux.alibaba.com>,
Joel Becker <jlbec@evilplan.org>
Subject: [patch V2 5/7] fs/jbd2: Simplify journal_unmap_buffer()
Date: Thu, 01 Aug 2019 03:01:31 +0200 [thread overview]
Message-ID: <20190801010944.364767635@linutronix.de> (raw)
In-Reply-To: 20190801010126.245731659@linutronix.de
journal_unmap_buffer() checks first whether the buffer head is a journal.
If so it takes locks and then invokes jbd2_journal_grab_journal_head()
followed by another check whether this is journal head buffer.
The double checking is pointless.
Replace the initial check with jbd2_journal_grab_journal_head() which
alredy checks whether the buffer head is actually a journal.
Allows also early access to the journal head pointer for the upcoming
conversion of state lock to a regular spinlock.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-ext4@vger.kernel.org
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan Kara <jack@suse.com>
---
V2: New patch
---
fs/jbd2/transaction.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -2196,7 +2196,8 @@ static int journal_unmap_buffer(journal_
* holding the page lock. --sct
*/
- if (!buffer_jbd(bh))
+ jh = jbd2_journal_grab_journal_head(bh);
+ if (!jh)
goto zap_buffer_unlocked;
/* OK, we have data buffer in journaled mode */
@@ -2204,10 +2205,6 @@ static int journal_unmap_buffer(journal_
jbd_lock_bh_state(bh);
spin_lock(&journal->j_list_lock);
- jh = jbd2_journal_grab_journal_head(bh);
- if (!jh)
- goto zap_buffer_no_jh;
-
/*
* We cannot remove the buffer from checkpoint lists until the
* transaction adding inode to orphan list (let's call it T)
@@ -2329,7 +2326,6 @@ static int journal_unmap_buffer(journal_
*/
jh->b_modified = 0;
jbd2_journal_put_journal_head(jh);
-zap_buffer_no_jh:
spin_unlock(&journal->j_list_lock);
jbd_unlock_bh_state(bh);
write_unlock(&journal->j_state_lock);
next prev parent reply other threads:[~2019-08-01 1:16 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-01 1:01 [patch V2 0/7] fs: Substitute bit-spinlocks for PREEMPT_RT and debugging Thomas Gleixner
2019-08-01 1:01 ` [patch V2 1/7] locking/lockdep: Add Kconfig option for bit spinlocks Thomas Gleixner
2019-08-01 1:01 ` [patch V2 2/7] fs/buffer: Move BH_Uptodate_Lock locking into wrapper functions Thomas Gleixner
2019-08-01 1:01 ` [patch V2 3/7] fs/buffer: Substitute BH_Uptodate_Lock for RT and bit spinlock debugging Thomas Gleixner
2019-08-01 1:01 ` [patch V2 4/7] fs/jbd2: Remove jbd_trylock_bh_state() Thomas Gleixner
2019-08-01 9:00 ` Jan Kara
2019-08-01 1:01 ` Thomas Gleixner [this message]
2019-08-01 9:04 ` [patch V2 5/7] fs/jbd2: Simplify journal_unmap_buffer() Jan Kara
2019-08-01 1:01 ` [patch V2 6/7] fs/jbd2: Make state lock a spinlock Thomas Gleixner
2019-08-01 11:28 ` Peter Zijlstra
2019-08-02 13:31 ` Jan Kara
2019-08-01 17:57 ` Jan Kara
2019-08-01 18:12 ` Thomas Gleixner
2019-08-02 13:37 ` Jan Kara
2019-08-02 15:29 ` Thomas Gleixner
2019-08-01 1:01 ` [patch V2 7/7] fs/jbd2: Free journal head outside of locked region Thomas Gleixner
2019-08-01 9:22 ` Jan Kara
2019-08-01 18:08 ` Thomas Gleixner
2019-08-02 7:56 ` [patch V2 0/7] fs: Substitute bit-spinlocks for PREEMPT_RT and debugging Christoph Hellwig
2019-08-02 9:07 ` Thomas Gleixner
2019-08-06 6:11 ` Christoph Hellwig
2019-08-08 7:02 ` Thomas Gleixner
2019-08-08 7:28 ` Christoph Hellwig
2019-08-08 7:54 ` Thomas Gleixner
2019-08-10 8:18 ` Christoph Hellwig
2019-08-11 1:22 ` Matthew Wilcox
2019-08-20 17:16 ` Sebastian Siewior
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190801010944.364767635@linutronix.de \
--to=tglx@linutronix.de \
--cc=anna-maria@linutronix.de \
--cc=bigeasy@linutronix.de \
--cc=jack@suse.com \
--cc=jack@suse.cz \
--cc=jlbec@evilplan.org \
--cc=joseph.qi@linux.alibaba.com \
--cc=julia@ni.com \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark@fasheh.com \
--cc=mingo@kernel.org \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=tytso@mit.edu \
--cc=viro@zeniv.linux.org.uk \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).