greate.
On Tue, Oct 1, 2019 at 3:53 PM harshad shirwadkar
<harshadshirwadkar@xxxxxxxxx> wrote:
>
> Oops, I missed this, I'll handle this in V4. Thanks!
>
> On Fri, Aug 9, 2019 at 1:02 PM Andreas Dilger <adilger@xxxxxxxxx> wrote:
> >
> > On Aug 8, 2019, at 9:45 PM, Harshad Shirwadkar <harshadshirwadkar@xxxxxxxxx> wrote:
> > >
> > > This patch allows file systems to turn fast commits on and thereby
> > > restrict the normal journalling space to total journal blocks minus
> > > JBD2_FAST_COMMIT_BLOCKS. Fast commits are not actually performed, just
> > > the interface to turn fast commits on is opened.
> > >
> > > Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@xxxxxxxxx>
> > >
> > > ---
> > >
> > > Changelog:
> > >
> > > V2: No changes since V1
> > > ---
> > > fs/ext4/super.c | 3 ++-
> > > fs/jbd2/journal.c | 39 ++++++++++++++++++++++++++++++++-------
> > > fs/ocfs2/journal.c | 4 ++--
> > > include/linux/jbd2.h | 2 +-
> > > 4 files changed, 37 insertions(+), 11 deletions(-)
> > >
> > > diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> > > index e376ac040cce..81c3ec165822 100644
> > > --- a/fs/ext4/super.c
> > > +++ b/fs/ext4/super.c
> > > @@ -4933,7 +4933,8 @@ static int ext4_load_journal(struct super_block *sb,
> > > if (save)
> > > memcpy(save, ((char *) es) +
> > > EXT4_S_ERR_START, EXT4_S_ERR_LEN);
> > > - err = jbd2_journal_load(journal);
> > > + err = jbd2_journal_load(journal,
> > > + test_opt2(sb, JOURNAL_FAST_COMMIT));
> > > if (save)
> > > memcpy(((char *) es) + EXT4_S_ERR_START,
> > > save, EXT4_S_ERR_LEN);
> > > diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
> > > index 953990eb70a9..59ad709154a3 100644
> > > --- a/fs/jbd2/journal.c
> > > +++ b/fs/jbd2/journal.c
> > > @@ -1159,12 +1159,15 @@ static journal_t *journal_init_common(struct block_device *bdev,
> > > journal->j_blk_offset = start;
> > > journal->j_maxlen = len;
> > > n = journal->j_blocksize / sizeof(journal_block_tag_t);
> > > - journal->j_wbufsize = n;
> > > + journal->j_wbufsize = n - JBD2_FAST_COMMIT_BLOCKS;
> >
> > The reservation of the JBD2_FAST_COMMIT_BLOCKS should only be done in
> > the case of the FAST_COMMIT feature being enabled. Otherwise it can
> > hurt performance for filesystems where this feature is not enabled.
> >
> > Cheers, Andreas
> >
> > > journal->j_wbuf = kmalloc_array(n, sizeof(struct buffer_head *),
> > > GFP_KERNEL);
> > > if (!journal->j_wbuf)
> > > goto err_cleanup;
> > >
> > > + journal->j_fc_wbuf = &journal->j_wbuf[journal->j_wbufsize];
> > > + journal->j_fc_wbufsize = JBD2_FAST_COMMIT_BLOCKS;
> > > +
> > > bh = getblk_unmovable(journal->j_dev, start, journal->j_blocksize);
> > > if (!bh) {
> > > pr_err("%s: Cannot get buffer for journal superblock\n",
> > > @@ -1297,11 +1300,19 @@ static int journal_reset(journal_t *journal)
> > > }
> > >
> > > journal->j_first = first;
> > > - journal->j_last = last;
> > >
> > > - journal->j_head = first;
> > > - journal->j_tail = first;
> > > - journal->j_free = last - first;
> > > + if (jbd2_has_feature_fast_commit(journal)) {
> > > + journal->j_last_fc = last;
> > > + journal->j_last = last - JBD2_FAST_COMMIT_BLOCKS;
> > > + journal->j_first_fc = journal->j_last + 1;
> > > + journal->j_fc_off = 0;
> > > + } else {
> > > + journal->j_last = last;
> > > + }
> > > +
> > > + journal->j_head = journal->j_first;
> > > + journal->j_tail = journal->j_first;
> > > + journal->j_free = journal->j_last - journal->j_first;
> > >
> > > journal->j_tail_sequence = journal->j_transaction_sequence;
> > > journal->j_commit_sequence = journal->j_transaction_sequence - 1;
> > > @@ -1626,9 +1637,17 @@ static int load_superblock(journal_t *journal)
> > > journal->j_tail_sequence = be32_to_cpu(sb->s_sequence);
> > > journal->j_tail = be32_to_cpu(sb->s_start);
> > > journal->j_first = be32_to_cpu(sb->s_first);
> > > - journal->j_last = be32_to_cpu(sb->s_maxlen);
> > > journal->j_errno = be32_to_cpu(sb->s_errno);
> > >
> > > + if (jbd2_has_feature_fast_commit(journal)) {
> > > + journal->j_last_fc = be32_to_cpu(sb->s_maxlen);
> > > + journal->j_last = journal->j_last_fc - JBD2_FAST_COMMIT_BLOCKS;
> > > + journal->j_first_fc = journal->j_last + 1;
> > > + journal->j_fc_off = 0;
> > > + } else {
> > > + journal->j_last = be32_to_cpu(sb->s_maxlen);
> > > + }
> > > +
> > > return 0;
> > > }
> > >
> > > @@ -1641,7 +1660,7 @@ static int load_superblock(journal_t *journal)
> > > * a journal, read the journal from disk to initialise the in-memory
> > > * structures.
> > > */
> > > -int jbd2_journal_load(journal_t *journal)
> > > +int jbd2_journal_load(journal_t *journal, bool enable_fc)
> > > {
> > > int err;
> > > journal_superblock_t *sb;
> > > @@ -1684,6 +1703,12 @@ int jbd2_journal_load(journal_t *journal)
> > > return -EFSCORRUPTED;
> > > }
> > >
> > > + if (enable_fc)
> > > + jbd2_journal_set_features(journal, 0, 0,
> > > + JBD2_FEATURE_INCOMPAT_FAST_COMMIT);
> > > + else
> > > + jbd2_journal_clear_features(journal, 0, 0,
> > > + JBD2_FEATURE_INCOMPAT_FAST_COMMIT);
> > > /* OK, we've finished with the dynamic journal bits:
> > > * reinitialise the dynamic contents of the superblock in memory
> > > * and reset them on disk. */
> > > diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
> > > index 930e3d388579..3b4d91b16e8e 100644
> > > --- a/fs/ocfs2/journal.c
> > > +++ b/fs/ocfs2/journal.c
> > > @@ -1057,7 +1057,7 @@ int ocfs2_journal_load(struct ocfs2_journal *journal, int local, int replayed)
> > >
> > > osb = journal->j_osb;
> > >
> > > - status = jbd2_journal_load(journal->j_journal);
> > > + status = jbd2_journal_load(journal->j_journal, false);
> > > if (status < 0) {
> > > mlog(ML_ERROR, "Failed to load journal!\n");
> > > goto done;
> > > @@ -1642,7 +1642,7 @@ static int ocfs2_replay_journal(struct ocfs2_super *osb,
> > > goto done;
> > > }
> > >
> > > - status = jbd2_journal_load(journal);
> > > + status = jbd2_journal_load(journal, false);
> > > if (status < 0) {
> > > mlog_errno(status);
> > > if (!igrab(inode))
> > > diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
> > > index 9a750b732241..153840b422cc 100644
> > > --- a/include/linux/jbd2.h
> > > +++ b/include/linux/jbd2.h
> > > @@ -1476,7 +1476,7 @@ extern int jbd2_journal_set_features
> > > (journal_t *, unsigned long, unsigned long, unsigned long);
> > > extern void jbd2_journal_clear_features
> > > (journal_t *, unsigned long, unsigned long, unsigned long);
> > > -extern int jbd2_journal_load (journal_t *journal);
> > > +extern int jbd2_journal_load(journal_t *journal, bool enable_fc);
> > > extern int jbd2_journal_destroy (journal_t *);
> > > extern int jbd2_journal_recover (journal_t *journal);
> > > extern int jbd2_journal_wipe (journal_t *, int);
> > > --
> > > 2.23.0.rc1.153.gdeed80330f-goog
> > >
> >
> >
> > Cheers, Andreas
> >
> >
> >
> >
> >
