Apparently, bitmap_andnot is supposed to return whether the new bitmap
is empty. But it didn't take potential garbage bits in the last word
into account.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Apparently, bitmap_and is supposed to return whether the new bitmap is
empty. But it didn't take potential garbage bits in the last word into
account.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is no guarantee that *src does not contain garbage bits outside
the lower nbits, so we need to mask it before the shift-and-assign.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Changing the pos parameter of __reg_op to unsigned allows the compiler
to generate slightly smaller and simpler code. Also update its callers
bitmap_*_region to receive and pass unsigned int. The return types of
bitmap_find_free_region and bitmap_allocate_region are still int to
allow a negative error code to be returned. An int is certainly capable
of representing any realistic return value.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The compiler can generate slightly smaller and simpler code when it
knows that "start" is non-negative.
Also, use the names "start" and "len" for the two parameters for
consistency with bitmap_set.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The compiler can generate slightly smaller and simpler code when it
knows that "start" is non-negative.
Also, use the names "start" and "len" for the two parameters in both
header file and implementation, instead of the previous mix.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The compiler can generate slightly smaller and simpler code when it
knows that "nbits" is non-negative. Since no-one passes a negative
bit-count, this shouldn't affect the semantics.
I didn't change the return type, since that might change the semantics
of some expression containing a call to bitmap_weight(). Certainly an
int is capable of holding the result.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The compiler can generate slightly smaller and simpler code when it
knows that "nbits" is non-negative. Since no-one passes a negative
bit-count, this shouldn't affect the semantics.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The compiler can generate slightly smaller and simpler code when it
knows that "nbits" is non-negative. Since no-one passes a negative
bit-count, this shouldn't affect the semantics.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This change is only for consistency with the changes to the other
bitmap_* functions; it doesn't change the size of the generated code:
inside BITS_TO_LONGS there is a sizeof(long), which causes bits to be
interpreted as unsigned anyway.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since the extra bits are "don't care", there is no reason to mask the
last word to the used bits when complementing. This shaves off yet a
few bytes.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The compiler can generate slightly smaller and simpler code when it
knows that "nbits" is non-negative. Since no-one passes a negative
bit-count, this shouldn't affect the semantics.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The compiler can generate slightly smaller and simpler code when it
knows that "nbits" is non-negative. Since no-one passes a negative
bit-count, this shouldn't affect the semantics.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The compiler can generate slightly smaller and simpler code when it
knows that "nbits" is non-negative. Since no-one passes a negative
bit-count, this shouldn't affect the semantics.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Many functions in lib/bitmap.c start with an expression such as lim =
bits/BITS_PER_LONG. Since bits has type (signed) int, and since gcc
cannot know that it is in fact non-negative, it generates worse code
than it could. These patches, mostly consisting of changing various
parameters to unsigned, gives a slight overall code reduction:
add/remove: 1/1 grow/shrink: 8/16 up/down: 251/-414 (-163)
function old new delta
tick_device_uses_broadcast 335 425 +90
__irq_alloc_descs 498 554 +56
__bitmap_andnot 73 115 +42
__bitmap_and 70 101 +31
bitmap_weight - 11 +11
copy_hugetlb_page_range 752 762 +10
follow_hugetlb_page 846 854 +8
hugetlb_init 1415 1417 +2
hugetlb_nrpages_setup 130 131 +1
hugetlb_add_hstate 377 376 -1
bitmap_allocate_region 82 80 -2
select_task_rq_fair 2202 2191 -11
hweight_long 66 55 -11
__reg_op 230 219 -11
dm_stats_message 2849 2833 -16
bitmap_parselist 92 74 -18
__bitmap_weight 115 97 -18
__bitmap_subset 153 129 -24
__bitmap_full 128 104 -24
__bitmap_empty 120 96 -24
bitmap_set 179 149 -30
bitmap_clear 185 155 -30
__bitmap_equal 136 105 -31
__bitmap_intersects 148 108 -40
__bitmap_complement 109 67 -42
tick_device_setup_broadcast_func.isra 81 - -81
[The increases in __bitmap_and{,not} are due to bug fixes 17/18,18/18.
No idea why bitmap_weight suddenly appears.] While 163 bytes treewide is
insignificant, I believe the bitmap functions are often called with
locks held, so saving even a few cycles might be worth it.
While making these changes, I found a few other things that might be
worth including. 16,17,18 are actual bug fixes. The rest shouldn't
change the behaviour of any of the functions, provided no-one passed
negative nbits values. If something should come up, it should be fairly
bisectable.
A few issues I thought about, but didn't know what to do with:
* Many of the functions misbehave if nbits is compile-time 0; the
out-of-line functions generally handle 0 correctly. bitmap_fill() is
particularly bad, whether the 0 is known at compile time or not. It
would probably be nice to add detection of at least compile-time 0 and
handle that appropriately.
* I didn't change __bitmap_shift_{left,right} to use unsigned because I
want to fully understand why the algorithm works before making that
change. However, AFAICT, they behave correctly for all (positive) shift
amounts. This is not the case for the small_const_nbits versions. If
for example nbits = n = BITS_PER_LONG, the shift operators turn into
no-ops (at least on x86), so one get *dst = *src, whereas one would
expect to get *dst=0. That difference in behaviour is somewhat
annoying.
This patch (of 18):
The compiler can generate slightly smaller and simpler code when it
knows that "nbits" is non-negative. Since no-one passes a negative
bit-count, this shouldn't affect the semantics.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some trivial conflicts due to other various merges
adding to the end of common lists sooner than this one.
arch/ia64/Kconfig
arch/powerpc/Kconfig
arch/x86/Kconfig
lib/Kconfig
lib/Makefile
Signed-off-by: Len Brown <len.brown@intel.com>
This version of the gen_pool memory allocator supports lockless
operation.
This makes it safe to use in NMI handlers and other special
unblockable contexts that could otherwise deadlock on locks. This is
implemented by using atomic operations and retries on any conflicts.
The disadvantage is that there may be livelocks in extreme cases. For
better scalability, one gen_pool allocator can be used for each CPU.
The lockless operation only works if there is enough memory available.
If new memory is added to the pool a lock has to be still taken. So
any user relying on locklessness has to ensure that sufficient memory
is preallocated.
The basic atomic operation of this allocator is cmpxchg on long. On
architectures that don't have NMI-safe cmpxchg implementation, the
allocator can NOT be used in NMI handler. So code uses the allocator
in NMI handler should depend on CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
[ This patch has already been accepted as commit 0ac0c0d0f8 but later
reverted (commit 35926ff5fb) because it itroduced arch specific
__node_random which was defined only for x86 code so it broke other
archs. This is a followup without any arch specific code. Other than
that there are no functional changes.]
Some workloads that create a large number of small files tend to assign
too many pages to node 0 (multi-node systems). Part of the reason is
that the rotor (in cpuset_mem_spread_node()) used to assign nodes starts
at node 0 for newly created tasks.
This patch changes the rotor to be initialized to a random node number
of the cpuset.
[akpm@linux-foundation.org: fix layout]
[Lee.Schermerhorn@hp.com: Define stub numa_random() for !NUMA configuration]
[mhocko@suse.cz: Make it arch independent]
[akpm@linux-foundation.org: fix CONFIG_NUMA=y, MAX_NUMNODES>1 build]
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Paul Menage <menage@google.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Paul Menage <menage@google.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Robin Holt <holt@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Manually adjusting the smp_affinity for IRQ's becomes unwieldy when the
cpu count is large.
Setting smp affinity to cpus 256 to 263 would be:
echo 000000ff,00000000,00000000,00000000,00000000,00000000,00000000,00000000 > smp_affinity
instead of:
echo 256-263 > smp_affinity_list
Think about what it looks like for cpus around say, 4088 to 4095.
We already have many alternate "list" interfaces:
/sys/devices/system/cpu/cpuX/indexY/shared_cpu_list
/sys/devices/system/cpu/cpuX/topology/thread_siblings_list
/sys/devices/system/cpu/cpuX/topology/core_siblings_list
/sys/devices/system/node/nodeX/cpulist
/sys/devices/pci***/***/local_cpulist
Add a companion interface, smp_affinity_list to use cpu lists instead of
cpu maps. This conforms to other companion interfaces where both a map
and a list interface exists.
This required adding a bitmap_parselist_user() function in a manner
similar to the bitmap_parse_user() function.
[akpm@linux-foundation.org: make __bitmap_parselist() static]
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 0ac0c0d0f8, which
caused cross-architecture build problems for all the wrong reasons.
IA64 already added its own version of __node_random(), but the fact is,
there is nothing architectural about the function, and the original
commit was just badly done. Revert it, since no fix is forthcoming.
Requested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some workloads that create a large number of small files tend to assign
too many pages to node 0 (multi-node systems). Part of the reason is that
the rotor (in cpuset_mem_spread_node()) used to assign nodes starts at
node 0 for newly created tasks.
This patch changes the rotor to be initialized to a random node number of
the cpuset.
[akpm@linux-foundation.org: fix layout]
[Lee.Schermerhorn@hp.com: Define stub numa_random() for !NUMA configuration]
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Paul Menage <menage@google.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When 'and'ing two bitmasks (where 'andnot' is a variation on it), some
cases want to know whether the result is the empty set or not. In
particular, the TLB IPI sending code wants to do cpumask operations and
determine if there are any CPU's left in the final set.
So this just makes the bitmask (and cpumask) functions return a boolean
for whether the result has any bits set.
Cc: stable@kernel.org (2.6.30, needed by TLB shootdown fix)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Impact: reduce text size
bitmap_zero et al have a fastpath for nbits <= BITS_PER_LONG, but this
should really only apply where the nbits is known at compile time.
This only saves about 1200 bytes on an allyesconfig kernel, but with
cpumasks going variable that number will increase.
text data bss dec hex filename
35327852 5035607 6782976 47146435 2cf65c3 vmlinux-before
35326640 5035607 6782976 47145223 2cf6107 vmlinux-after
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/dvrabel/uwb: (47 commits)
uwb: wrong sizeof argument in mac address compare
uwb: don't use printk_ratelimit() so often
uwb: use kcalloc where appropriate
uwb: use time_after() when purging stale beacons
uwb: add credits for the original developers of the UWB/WUSB/WLP subsystems
uwb: add entries in the MAINTAINERS file
uwb: depend on EXPERIMENTAL
wusb: wusb-cbaf (CBA driver) sysfs ABI simplification
uwb: document UWB and WUSB sysfs files
uwb: add symlinks in sysfs between radio controllers and PALs
uwb: dont tranmit identification IEs
uwb: i1480/GUWA100U: fix firmware download issues
uwb: i1480: remove MAC/PHY information checking function
uwb: add Intel i1480 HWA to the UWB RC quirk table
uwb: disable command/event filtering for D-Link DUB-1210
uwb: initialize the debug sub-system
uwb: Fix handling IEs with empty IE data in uwb_est_get_size()
wusb: fix bmRequestType for Abort RPipe request
wusb: fix error path for wusb_set_dev_addr()
wusb: add HWA host controller driver
...
