Re: [PATCH] f2fs: move f2fs_balance_fs from truncate to punch_hole

[Namjae Jeon]

2013/4/9, Jason Hrycay <jhrycay@xxxxxxxxx>:
> From: Jason Hrycay <jason.hrycay@xxxxxxxxxxxx>
>
> Move the f2fs_balance_fs out of the truncate_hole function and only
> perform that in punch_hole use case.  The commit:
>
>   ed60b1644e7f7e5dd67d21caf7e4425dff05dad0
>
> intended to do this but moved it into truncate_hole to cover more
> cases.  However, a deadlock scenario is possible when deleting an inode
> entry under specific conditions:
>
>  f2fs_delete_entry()
>      mutex_lock_op(sbi, DENTRY_OPS);
>      truncate_hole()
>          f2fs_balance_fs()
>              mutex_lock(&sbi->gc_mutex);
>              f2fs_gc()
>                  write_checkpoint()
>                      block_operations()
>                          mutex_lock_op(sbi, DENTRY_OPS);
>
> Lets move it into the punch_hole case to cover the original intent of
> avoiding it during fallocate's expand_inode_data case.
>
> Change-Id: I29f8ea1056b0b88b70ba8652d901b6e8431bb27e
> Signed-off-by: Jason Hrycay <jason.hrycay@xxxxxxxxxxxx>
Hi,
With the latest commit 9995bf953a83749abd9fa22f72ab2b0be341025a
About introducing the global locking method in âf2fsâ,
I think we no longer will have a case of deadlock happening in this path.

Thanks.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/