ocfs2: Support commit= mount option

Mostly taken from ext3. This allows the user to set the jbd commit interval,
in seconds. The default of 5 seconds stays the same, but now users can
easily increase the commit interval. Typically, this would be increased in
order to benefit performance at the expense of data-safety.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

diff --git a/Documentation/filesystems/ocfs2.txt b/Documentation/filesystems/ocfs2.txt
index e78abdcc59eef4219012a3b263216e5621fd8c32..b63bd2d7fcd3017bc8d63206da7e7978d143bce9 100644 (file)
--- a/Documentation/filesystems/ocfs2.txt
+++ b/Documentation/filesystems/ocfs2.txt
@@ -61,3 +61,14 @@ data=writeback               Data ordering is not preserved, data may be written
 preferred_slot=0(*)    During mount, try to use this filesystem slot first. If
                        it is in use by another node, the first empty one found
                        will be chosen. Invalid values will be ignored.
+commit=nrsec   (*)     Ocfs2 can be told to sync all its data and metadata
+                       every 'nrsec' seconds. The default value is 5 seconds.
+                       This means that if you lose your power, you will lose
+                       as much as the latest 5 seconds of work (your
+                       filesystem will not be damaged though, thanks to the
+                       journaling).  This default value (or any low value)
+                       will hurt performance, but it's good for data-safety.
+                       Setting it to 0 will have the same effect as leaving
+                       it at the default (5 seconds).
+                       Setting it to very large values will improve
+                       performance.

diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
index 4f440a88bf53ab34a315e8b638fd97001f8e25af..8b9ce2a729ab5583ffbc4ab41a6bc500f57bd8d5 100644 (file)
--- a/fs/ocfs2/journal.c
+++ b/fs/ocfs2/journal.c
@@ -313,14 +313,18 @@ int ocfs2_journal_dirty_data(handle_t *handle,
        return err;
 }
 
-#define OCFS2_DEFAULT_COMMIT_INTERVAL  (HZ * 5)
+#define OCFS2_DEFAULT_COMMIT_INTERVAL  (HZ * JBD_DEFAULT_MAX_COMMIT_AGE)
 
 void ocfs2_set_journal_params(struct ocfs2_super *osb)
 {
        journal_t *journal = osb->journal->j_journal;
+       unsigned long commit_interval = OCFS2_DEFAULT_COMMIT_INTERVAL;
+
+       if (osb->osb_commit_interval)
+               commit_interval = osb->osb_commit_interval;
 
        spin_lock(&journal->j_state_lock);
-       journal->j_commit_interval = OCFS2_DEFAULT_COMMIT_INTERVAL;
+       journal->j_commit_interval = commit_interval;
        if (osb->s_mount_opt & OCFS2_MOUNT_BARRIER)
                journal->j_flags |= JFS_BARRIER;
        else

diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index f8f866144c6a3c9d1bff174d8cd4840bb854c4cf..82802f5672a1859a1932df82b42eba42795a2eee 100644 (file)
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -229,6 +229,7 @@ struct ocfs2_super
        wait_queue_head_t checkpoint_event;
        atomic_t needs_checkpoint;
        struct ocfs2_journal *journal;
+       unsigned long osb_commit_interval;
 
        enum ocfs2_local_alloc_state local_alloc_state;
        struct buffer_head *local_alloc_bh;

diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 479ac50c86d9d93321875b671e73481db1ce6b47..8044ed97d36263161ad0c81ebb36225df56f08d4 100644 (file)
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -83,6 +83,7 @@ MODULE_LICENSE("GPL");
 
 struct mount_options
 {
+       unsigned long   commit_interval;
        unsigned long   mount_opt;
        unsigned int    atime_quantum;
        signed short    slot;
@@ -149,6 +150,7 @@ enum {
        Opt_data_writeback,
        Opt_atime_quantum,
        Opt_slot,
+       Opt_commit,
        Opt_err,
 };
 
@@ -164,6 +166,7 @@ static match_table_t tokens = {
        {Opt_data_writeback, "data=writeback"},
        {Opt_atime_quantum, "atime_quantum=%u"},
        {Opt_slot, "preferred_slot=%u"},
+       {Opt_commit, "commit=%u"},
        {Opt_err, NULL}
 };
 
@@ -442,6 +445,8 @@ unlock_osb:
                osb->s_mount_opt = parsed_options.mount_opt;
                osb->s_atime_quantum = parsed_options.atime_quantum;
                osb->preferred_slot = parsed_options.slot;
+               if (parsed_options.commit_interval)
+                       osb->osb_commit_interval = parsed_options.commit_interval;
 
                if (!ocfs2_is_hard_readonly(osb))
                        ocfs2_set_journal_params(osb);
@@ -596,6 +601,7 @@ static int ocfs2_fill_super(struct super_block *sb, void *data, int silent)
        osb->s_mount_opt = parsed_options.mount_opt;
        osb->s_atime_quantum = parsed_options.atime_quantum;
        osb->preferred_slot = parsed_options.slot;
+       osb->osb_commit_interval = parsed_options.commit_interval;
 
        sb->s_magic = OCFS2_SUPER_MAGIC;
 
@@ -746,6 +752,7 @@ static int ocfs2_parse_options(struct super_block *sb,
        mlog_entry("remount: %d, options: \"%s\"\n", is_remount,
                   options ? options : "(none)");
 
+       mopt->commit_interval = 0;
        mopt->mount_opt = 0;
        mopt->atime_quantum = OCFS2_DEFAULT_ATIME_QUANTUM;
        mopt->slot = OCFS2_INVALID_SLOT;
@@ -815,6 +822,18 @@ static int ocfs2_parse_options(struct super_block *sb,
                        if (option)
                                mopt->slot = (s16)option;
                        break;
+               case Opt_commit:
+                       option = 0;
+                       if (match_int(&args[0], &option)) {
+                               status = 0;
+                               goto bail;
+                       }
+                       if (option < 0)
+                               return 0;
+                       if (option == 0)
+                               option = JBD_DEFAULT_MAX_COMMIT_AGE;
+                       mopt->commit_interval = HZ * option;
+                       break;
                default:
                        mlog(ML_ERROR,
                             "Unrecognized mount option \"%s\" "
@@ -863,6 +882,10 @@ static int ocfs2_show_options(struct seq_file *s, struct vfsmount *mnt)
        if (osb->s_atime_quantum != OCFS2_DEFAULT_ATIME_QUANTUM)
                seq_printf(s, ",atime_quantum=%u", osb->s_atime_quantum);
 
+       if (osb->osb_commit_interval)
+               seq_printf(s, ",commit=%u",
+                          (unsigned) (osb->osb_commit_interval / HZ));
+
        return 0;
 }