Btrfs devel - Dec 2010 - PATCH: btrfs ioctl for waiting for kernel cleaner thread task completions kernel code

the attached patch is against ubuntu maverick latest git, and I
believe it is final. It is forward-compatible, as there is space in it
to define 29 more deferred things to wait for, if needed, as well as a
flag bit reserved for strict versioning. Calling it with a flags field
of 0xFFFFFFFA will wait for everything it knows how to wait for,
including things it doesn''t know how to wait for now.

It is also architecture-safe, using u32 in the interface arg structure
instead of unisgned long.

A revised btrfs-progs patch (that uses __u32 instead of unsigned long
in the interface object) will be forthcoming soon, to the btrfs list.

Question: is it safe to examine list_empty(fs->delayed_iputs) without
taking the spinlock that protects that list in inode.c?


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“The aeroplane is fatally defective. It is merely a toy—a sporting
play-thing.  It can never become commercially practical." -- Nikola
Tesla