kernel_optimize_test/tools
Matthew Wilcox afe0e395b6 radix-tree: fix several shrinking bugs with multiorder entries
Setting the indirect bit on the user data entry used to be unambiguous
because the tree walking code knew not to expect internal nodes in the
last level of the tree.  Multiorder entries can appear at any level of
the tree, and a leaf with the indirect bit set is indistinguishable from
a pointer to a node.

Introduce a special entry (RADIX_TREE_RETRY) which is neither a valid
user entry, nor a valid pointer to a node.  The radix_tree_deref_retry()
function continues to work the same way, but tree walking code can
distinguish it from a pointer to a node.

Also fix the condition for setting slot->parent to NULL; it does not
matter what height the tree is, it only matters whether slot is an
indirect pointer.  Move this code above the comment which is referring
to the assignment to root->rnode.

Also fix the condition for preventing the tree from shrinking to a
single entry if it's a multiorder entry.

Add a test-case to the test suite that checks that the tree goes back
down to its original height after an item is inserted & deleted from a
higher index in the tree.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Jan Kara <jack@suse.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20 17:58:30 -07:00
..
arch
build perf probe: Check if dwarf_getlocations() is available 2016-05-12 11:26:59 -03:00
cgroup
firewire
gpio
hv
iio
include
laptop/freefall
lguest tools/lguest: Force disable tboot and APM 2016-04-22 10:29:03 +02:00
lib Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-05-16 14:08:43 -07:00
net tools: bpf_jit_disasm: check for klogctl failure 2016-05-08 23:32:59 -04:00
nfsd
objtool objtool: Detect falling through to the next function 2016-04-16 11:14:17 +02:00
perf powerpc updates for 4.7 2016-05-20 10:12:41 -07:00
power ACPI material for v4.7-rc1 2016-05-16 19:41:41 -07:00
scripts
spi
testing radix-tree: fix several shrinking bugs with multiorder entries 2016-05-20 17:58:30 -07:00
thermal/tmon
time
usb
virtio
vm
Makefile tools build: Fix perf_clean target 2016-04-25 17:59:36 -03:00