linux/include
Matthew Wilcox f6bb2a2c0b xarray: add the xa_lock to the radix_tree_root
This results in no change in structure size on 64-bit machines as it
fits in the padding between the gfp_t and the void *.  32-bit machines
will grow the structure from 8 to 12 bytes.  Almost all radix trees are
protected with (at least) a spinlock, so as they are converted from
radix trees to xarrays, the data structures will shrink again.

Initialising the spinlock requires a name for the benefit of lockdep, so
RADIX_TREE_INIT() now needs to know the name of the radix tree it's
initialising, and so do IDR_INIT() and IDA_INIT().

Also add the xa_lock() and xa_unlock() family of wrappers to make it
easier to use the lock.  If we could rely on -fplan9-extensions in the
compiler, we could avoid all of this syntactic sugar, but that wasn't
added until gcc 4.6.

Link: http://lkml.kernel.org/r/20180313132639.17387-8-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:39 -07:00
..
acpi pci-v4.17-changes 2018-04-06 18:31:06 -07:00
asm-generic ARM: 2018-04-09 11:42:31 -07:00
clocksource ARM: SoC platform updates for 4.17 2018-04-05 21:21:08 -07:00
crypto
drm
dt-bindings ARM: SoC driver updates for 4.17 2018-04-05 21:29:35 -07:00
keys
kvm
linux xarray: add the xa_lock to the radix_tree_root 2018-04-11 10:28:39 -07:00
math-emu
media media updates for v4.17-rc1 2018-04-10 10:10:30 -07:00
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-04-09 17:04:10 -07:00
pcmcia
ras
rdma Merge candidates for 4.17 merge window 2018-04-06 17:35:43 -07:00
scsi SCSI for-linus on 20180404 2018-04-05 15:05:53 -07:00
soc ARM: SoC driver updates for 4.17 2018-04-05 21:29:35 -07:00
sound sound updates for 4.17-rc1 2018-04-05 10:42:07 -07:00
target
trace mm, vmscan, tracing: use pointer to reclaim_stat struct in trace event 2018-04-11 10:28:30 -07:00
uapi linux/const.h: refactor _BITUL and _BITULL a bit 2018-04-11 10:28:38 -07:00
video
xen