Johannes Weiner 14b468791f mm: workingset: move shadow entry tracking to radix tree exceptional tracking ... Currently, we track the shadow entries in the page cache in the upper bits of the radix_tree_node->count, behind the back of the radix tree implementation. Because the radix tree code has no awareness of them, we rely on random subtleties throughout the implementation (such as the node->count != 1 check in the shrinking code, which is meant to exclude multi-entry nodes but also happens to skip nodes with only one shadow entry, as that's accounted in the upper bits). This is error prone and has, in fact, caused the bug fixed in d3798ae8c6 ("mm: filemap: don't plant shadow entries without radix tree node"). To remove these subtleties, this patch moves shadow entry tracking from the upper bits of node->count to the existing counter for exceptional entries. node->count goes back to being a simple counter of valid entries in the tree node and can be shrunk to a single byte. This vastly simplifies the page cache code. All accounting happens natively inside the radix tree implementation, and maintaining the LRU linkage of shadow nodes is consolidated into a single function in the workingset code that is called for leaf nodes affected by a change in the page cache tree. This also removes the last user of the __radix_delete_node() return value. Eliminate it. Link: http://lkml.kernel.org/r/20161117193211.GE23430@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox <mawilcox@linuxonhyperv.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2016-12-12 18:55:08 -08:00
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acpi	Merge branches 'acpica-fixes', 'acpi-cppc-fixes' and 'acpi-tools-fixes'	2016-11-18 21:34:42 +01:00
asm-generic	mm: remove the page size change check in tlb_remove_page	2016-12-12 18:55:07 -08:00
clocksource
crypto	crypto: drbg - prevent invalid SG mappings	2016-11-30 19:46:44 +08:00
drm
dt-bindings	dt-bindings: net: add EEE capability constants	2016-11-29 19:38:31 -05:00
keys
kvm
linux	mm: workingset: move shadow entry tracking to radix tree exceptional tracking	2016-12-12 18:55:08 -08:00
math-emu
media
memory
misc
net	Three fixes:	2016-12-09 22:59:05 -05:00
pcmcia
ras
rdma
rxrpc
scsi
soc
sound
target
trace	Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-12-12 09:09:54 -08:00
uapi	net: l2tp: deprecate PPPOL2TP_MSG_* in favour of L2TP_MSG_*	2016-12-10 23:29:11 -05:00
video
xen
Kbuild