Commit Graph

6 Commits

Author SHA1 Message Date
Linus Torvalds
f94181da71 Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: fix rcutorture bug
  rcu: eliminate synchronize_rcu_xxx macro
  rcu: make treercu safe for suspend and resume
  rcu: fix rcutree grace-period-latency bug on small systems
  futex: catch certain assymetric (get|put)_futex_key calls
  futex: make futex_(get|put)_key() calls symmetric
  locking, percpu counters: introduce separate lock classes
  swiotlb: clean up EXPORT_SYMBOL usage
  swiotlb: remove unnecessary declaration
  swiotlb: replace architecture-specific swiotlb.h with linux/swiotlb.h
  swiotlb: add support for systems with highmem
  swiotlb: store phys address in io_tlb_orig_addr array
  swiotlb: add hwdev to swiotlb_phys_to_bus() / swiotlb_sg_to_bus()
2009-01-06 17:10:04 -08:00
Harvey Harrison
3007967742 lib: proportions.c trivial sparse lock annotation
Suppresses sparse warning:
lib/proportions.c:159:16: warning: context imbalance in 'prop_get_global': wrong count at exit
lib/proportions.c:159:16:    context 'RCU': wanted 0, got 1
lib/proportions.c:164:2: warning: context imbalance in 'prop_put_global': unexpected unlock
lib/proportions.c:164:2:    context 'RCU': wanted 0, got -1

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:11 -08:00
Peter Zijlstra
ea319518ba locking, percpu counters: introduce separate lock classes
Impact: fix lockdep false positives

Classify percpu_counter instances similar to regular lock objects --
that is, per instantiation site.

The networking code has increased its use of percpu_counters, which
leads to false positives if they are treated as a single class.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-29 13:43:00 +01:00
Peter Zijlstra
a42dde0415 mm: bdi: allow setting a maximum for the bdi dirty limit
Add "max_ratio" to /sys/class/bdi.  This indicates the maximum percentage of
the global dirty threshold allocated to this bdi.

[mszeredi@suse.cz]

 - fix parsing in max_ratio_store().
 - export bdi_set_max_ratio() to modules
 - limit bdi_dirty with bdi->max_ratio
 - document new sysfs attribute

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
Peter Zijlstra
f16b34aa13 lib: proportion: fix underflow in prop_norm_percpu()
Zhe Jiang noticed that its possible to underflow pl->events in
prop_norm_percpu() when the value returned by percpu_counter_read() is less
than the error on that read and the period delay > 1.  In that case half might
not trigger the batch increment and the value will be identical on the next
iteration, causing the same half to be subtracted again and again.

Fix this by rewriting the division as a single subtraction instead of a
subtraction loop and using percpu_counter_sum() when the value returned by
percpu_counter_read() is smaller than the error.

The latter is still needed if we want pl->events to shrink properly in the
error region.

[akpm@linux-foundation.org: cleanups]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Jiang Zhe <zhe.jiang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-23 12:54:37 -08:00
Peter Zijlstra
145ca25eb2 lib: floating proportions
Given a set of objects, floating proportions aims to efficiently give the
proportional 'activity' of a single item as compared to the whole set. Where
'activity' is a measure of a temporal property of the items.

It is efficient in that it need not inspect any other items of the set
in order to provide the answer. It is not even needed to know how many
other items there are.

It has one parameter, and that is the period of 'time' over which the
'activity' is measured.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:45 -07:00