Re: [RFC v3 01/13] btrfs: add one new mount option '-o hot_track'

[Zhi Yong Wu <zwu.kernel@gmail.com>]

On Wed, Oct 10, 2012 at 9:11 PM, Lukáš Czerner <lczerner@redhat.com> wrote:
> On Wed, 10 Oct 2012, Zhi Yong Wu wrote:
>
>> Date: Wed, 10 Oct 2012 20:21:48 +0800
>> From: Zhi Yong Wu <zwu.kernel@gmail.com>
>> To: Lukáš Czerner <lczerner@redhat.com>
>> Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org,
>>     linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org,
>>     linuxram@linux.vnet.ibm.com, viro@zeniv.linux.org.uk, david@fromorbit.com,
>>     dave@jikos.cz, tytso@mit.edu, cmm@us.ibm.com,
>>     Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
>> Subject: Re: [RFC v3 01/13] btrfs: add one new mount option '-o hot_track'
>>
>> On Wed, Oct 10, 2012 at 7:59 PM, Lukáš Czerner <lczerner@redhat.com> wrote:
>> > On Wed, 10 Oct 2012, zwu.kernel@gmail.com wrote:
>> >
>> >> Date: Wed, 10 Oct 2012 18:07:23 +0800
>> >> From: zwu.kernel@gmail.com
>> >> To: linux-fsdevel@vger.kernel.org
>> >> Cc: linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org,
>> >>     linux-kernel@vger.kernel.org, linuxram@linux.vnet.ibm.com,
>> >>     viro@zeniv.linux.org.uk, david@fromorbit.com, dave@jikos.cz,
>> >>     tytso@mit.edu, cmm@us.ibm.com, Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
>> >> Subject: [RFC v3 01/13] btrfs: add one new mount option '-o hot_track'
>> >>
>> >> From: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
>> >>
>> >> Introduce one new mount option '-o hot_track',
>> >> and add its parsing support.
>> >>   Its usage looks like:
>> >>    mount -o hot_track
>> >>    mount -o nouser,hot_track
>> >>    mount -o nouser,hot_track,loop
>> >>    mount -o hot_track,nouser
>> >
>> > This patch should probably be at the end of the series.
>> Can you let me know your reason? I think that it is not necessary to
>> be at the end of the series.
>
> Simply because you're adding the mount option which does not do
> anything yet. Moreover you change the implementation of the hot track
> as you go. You should enable this once it is ready to use, not the other
> way around. So, please move this at the end of the patch set when
> the feature is supposed to be ready to use.
OK, done, thanks. If you have comments on other patches, it will be appreciated.

>
> Thanks!
> -Lukas
>
>>
>> >
>> > -Lukas
>> >
>> >>
>> >> Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
>> >> ---
>> >>  fs/btrfs/ctree.h |    1 +
>> >>  fs/btrfs/super.c |    7 ++++++-
>> >>  2 files changed, 7 insertions(+), 1 deletions(-)
>> >>
>> >> diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
>> >> index 9821b67..094bec6 100644
>> >> --- a/fs/btrfs/ctree.h
>> >> +++ b/fs/btrfs/ctree.h
>> >> @@ -1726,6 +1726,7 @@ struct btrfs_ioctl_defrag_range_args {
>> >>  #define BTRFS_MOUNT_CHECK_INTEGRITY  (1 << 20)
>> >>  #define BTRFS_MOUNT_CHECK_INTEGRITY_INCLUDING_EXTENT_DATA (1 << 21)
>> >>  #define BTRFS_MOUNT_PANIC_ON_FATAL_ERROR     (1 << 22)
>> >> +#define BTRFS_MOUNT_HOT_TRACK                (1 << 23)
>> >>
>> >>  #define btrfs_clear_opt(o, opt)              ((o) &= ~BTRFS_MOUNT_##opt)
>> >>  #define btrfs_set_opt(o, opt)                ((o) |= BTRFS_MOUNT_##opt)
>> >> diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
>> >> index 83d6f9f..00be9e3 100644
>> >> --- a/fs/btrfs/super.c
>> >> +++ b/fs/btrfs/super.c
>> >> @@ -41,6 +41,7 @@
>> >>  #include <linux/slab.h>
>> >>  #include <linux/cleancache.h>
>> >>  #include <linux/ratelimit.h>
>> >> +#include <linux/hot_tracking.h>
>> >>  #include "compat.h"
>> >>  #include "delayed-inode.h"
>> >>  #include "ctree.h"
>> >> @@ -303,7 +304,7 @@ enum {
>> >>       Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard,
>> >>       Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed,
>> >>       Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, Opt_inode_cache,
>> >> -     Opt_no_space_cache, Opt_recovery, Opt_skip_balance,
>> >> +     Opt_no_space_cache, Opt_recovery, Opt_skip_balance, Opt_hot_track,
>> >>       Opt_check_integrity, Opt_check_integrity_including_extent_data,
>> >>       Opt_check_integrity_print_mask, Opt_fatal_errors,
>> >>       Opt_err,
>> >> @@ -342,6 +343,7 @@ static match_table_t tokens = {
>> >>       {Opt_no_space_cache, "nospace_cache"},
>> >>       {Opt_recovery, "recovery"},
>> >>       {Opt_skip_balance, "skip_balance"},
>> >> +     {Opt_hot_track, "hot_track"},
>> >>       {Opt_check_integrity, "check_int"},
>> >>       {Opt_check_integrity_including_extent_data, "check_int_data"},
>> >>       {Opt_check_integrity_print_mask, "check_int_print_mask=%d"},
>> >> @@ -553,6 +555,9 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
>> >>               case Opt_skip_balance:
>> >>                       btrfs_set_opt(info->mount_opt, SKIP_BALANCE);
>> >>                       break;
>> >> +             case Opt_hot_track:
>> >> +                     btrfs_set_opt(info->mount_opt, HOT_TRACK);
>> >> +                     break;
>> >>  #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
>> >>               case Opt_check_integrity_including_extent_data:
>> >>                       printk(KERN_INFO "btrfs: enabling check integrity"
>> >>
>>
>>
>>
>>



-- 
Regards,

Zhi Yong Wu