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2013-09-10list_lru: fix broken LRU_RETRY behaviourDave Chinner
The LRU_RETRY code assumes that the list traversal status after we have dropped and regained the list lock. Unfortunately, this is not a valid assumption, and that can lead to racing traversals isolating objects that the other traversal expects to be the next item on the list. This is causing problems with the inode cache shrinker isolation, with races resulting in an inode on a dispose list being "isolated" because a racing traversal still thinks it is on the LRU. The inode is then never reclaimed and that causes hangs if a subsequent lookup on that inode occurs. Fix it by always restarting the list walk on a LRU_RETRY return from the isolate callback. Avoid the possibility of livelocks the current code was trying to avoid by always decrementing the nr_to_walk counter on retries so that even if we keep hitting the same item on the list we'll eventually stop trying to walk and exit out of the situation causing the problem. Reported-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Dave Chinner <dchinner@redhat.com> Cc: Glauber Costa <glommer@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10list_lru: per-node list infrastructureDave Chinner
Now that we have an LRU list API, we can start to enhance the implementation. This splits the single LRU list into per-node lists and locks to enhance scalability. Items are placed on lists according to the node the memory belongs to. To make scanning the lists efficient, also track whether the per-node lists have entries in them in a active nodemask. Note: We use a fixed-size array for the node LRU, this struct can be very big if MAX_NUMNODES is big. If this becomes a problem this is fixable by turning this into a pointer and dynamically allocating this to nr_node_ids. This quantity is firwmare-provided, and still would provide room for all nodes at the cost of a pointer lookup and an extra allocation. Because that allocation will most likely come from a may very well fail. [glommer@openvz.org: fix warnings, added note about node lru] Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Glauber Costa <glommer@openvz.org> Reviewed-by: Greg Thelen <gthelen@google.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10dcache: convert to use new lru list infrastructureDave Chinner
[glommer@openvz.org: don't reintroduce double decrement of nr_unused_dentries, adapted for new LRU return codes] Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Glauber Costa <glommer@openvz.org> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10inode: move inode to a different list inside lockGlauber Costa
When removing an element from the lru, this will be done today after the lock is released. This is a clear mistake, although we are not sure if the bugs we are seeing are related to this. All list manipulations are done inside the lock, and so should this one. Signed-off-by: Glauber Costa <glommer@openvz.org> Tested-by: Michal Hocko <mhocko@suse.cz> Cc: Dave Chinner <dchinner@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10inode: convert inode lru list to generic lru list code.Dave Chinner
[glommer@openvz.org: adapted for new LRU return codes] Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Glauber Costa <glommer@openvz.org> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10list: add a new LRU list typeDave Chinner
Several subsystems use the same construct for LRU lists - a list head, a spin lock and and item count. They also use exactly the same code for adding and removing items from the LRU. Create a generic type for these LRU lists. This is the beginning of generic, node aware LRUs for shrinkers to work with. [glommer@openvz.org: enum defined constants for lru. Suggested by gthelen, don't relock over retry] Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Glauber Costa <glommer@openvz.org> Reviewed-by: Greg Thelen <gthelen@google.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10shrinker: convert superblock shrinkers to new APIDave Chinner
Convert superblock shrinker to use the new count/scan API, and propagate the API changes through to the filesystem callouts. The filesystem callouts already use a count/scan API, so it's just changing counters to longs to match the VM API. This requires the dentry and inode shrinker callouts to be converted to the count/scan API. This is mainly a mechanical change. [glommer@openvz.org: use mult_frac for fractional proportions, build fixes] Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Glauber Costa <glommer@openvz.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10mm: new shrinker APIDave Chinner
The current shrinker callout API uses an a single shrinker call for multiple functions. To determine the function, a special magical value is passed in a parameter to change the behaviour. This complicates the implementation and return value specification for the different behaviours. Separate the two different behaviours into separate operations, one to return a count of freeable objects in the cache, and another to scan a certain number of objects in the cache for freeing. In defining these new operations, ensure the return values and resultant behaviours are clearly defined and documented. Modify shrink_slab() to use the new API and implement the callouts for all the existing shrinkers. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Glauber Costa <glommer@parallels.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10dcache: remove dentries from LRU before putting on dispose listDave Chinner
One of the big problems with modifying the way the dcache shrinker and LRU implementation works is that the LRU is abused in several ways. One of these is shrink_dentry_list(). Basically, we can move a dentry off the LRU onto a different list without doing any accounting changes, and then use dentry_lru_prune() to remove it from what-ever list it is now on to do the LRU accounting at that point. This makes it -really hard- to change the LRU implementation. The use of the per-sb LRU lock serialises movement of the dentries between the different lists and the removal of them, and this is the only reason that it works. If we want to break up the dentry LRU lock and lists into, say, per-node lists, we remove the only serialisation that allows this lru list/dispose list abuse to work. To make this work effectively, the dispose list has to be isolated from the LRU list - dentries have to be removed from the LRU *before* being placed on the dispose list. This means that the LRU accounting and isolation is completed before disposal is started, and that means we can change the LRU implementation freely in future. This means that dentries *must* be marked with DCACHE_SHRINK_LIST when they are placed on the dispose list so that we don't think that parent dentries found in try_prune_one_dentry() are on the LRU when the are actually on the dispose list. This would result in accounting the dentry to the LRU a second time. Hence dentry_lru_del() has to handle the DCACHE_SHRINK_LIST case Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Glauber Costa <glommer@openvz.org> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10dentry: move to per-sb LRU locksDave Chinner
With the dentry LRUs being per-sb structures, there is no real need for a global dentry_lru_lock. The locking can be made more fine-grained by moving to a per-sb LRU lock, isolating the LRU operations of different filesytsems completely from each other. The need for this is independent of any performance consideration that may arise: in the interest of abstracting the lru operations away, it is mandatory that each lru works around its own lock instead of a global lock for all of them. [glommer@openvz.org: updated changelog ] Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Glauber Costa <glommer@openvz.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mel Gorman <mgorman@suse.de> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10dcache: convert dentry_stat.nr_unused to per-cpu countersDave Chinner
Before we split up the dcache_lru_lock, the unused dentry counter needs to be made independent of the global dcache_lru_lock. Convert it to per-cpu counters to do this. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Glauber Costa <glommer@openvz.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mel Gorman <mgorman@suse.de> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10super: fix calculation of shrinkable objects for small numbersGlauber Costa
The sysctl knob sysctl_vfs_cache_pressure is used to determine which percentage of the shrinkable objects in our cache we should actively try to shrink. It works great in situations in which we have many objects (at least more than 100), because the aproximation errors will be negligible. But if this is not the case, specially when total_objects < 100, we may end up concluding that we have no objects at all (total / 100 = 0, if total < 100). This is certainly not the biggest killer in the world, but may matter in very low kernel memory situations. Signed-off-by: Glauber Costa <glommer@openvz.org> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Dave Chinner <david@fromorbit.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10fs: bump inode and dentry counters to longGlauber Costa
This series reworks our current object cache shrinking infrastructure in two main ways: * Noticing that a lot of users copy and paste their own version of LRU lists for objects, we put some effort in providing a generic version. It is modeled after the filesystem users: dentries, inodes, and xfs (for various tasks), but we expect that other users could benefit in the near future with little or no modification. Let us know if you have any issues. * The underlying list_lru being proposed automatically and transparently keeps the elements in per-node lists, and is able to manipulate the node lists individually. Given this infrastructure, we are able to modify the up-to-now hammer called shrink_slab to proceed with node-reclaim instead of always searching memory from all over like it has been doing. Per-node lru lists are also expected to lead to less contention in the lru locks on multi-node scans, since we are now no longer fighting for a global lock. The locks usually disappear from the profilers with this change. Although we have no official benchmarks for this version - be our guest to independently evaluate this - earlier versions of this series were performance tested (details at http://permalink.gmane.org/gmane.linux.kernel.mm/100537) yielding no visible performance regressions while yielding a better qualitative behavior in NUMA machines. With this infrastructure in place, we can use the list_lru entry point to provide memcg isolation and per-memcg targeted reclaim. Historically, those two pieces of work have been posted together. This version presents only the infrastructure work, deferring the memcg work for a later time, so we can focus on getting this part tested. You can see more about the history of such work at http://lwn.net/Articles/552769/ Dave Chinner (18): dcache: convert dentry_stat.nr_unused to per-cpu counters dentry: move to per-sb LRU locks dcache: remove dentries from LRU before putting on dispose list mm: new shrinker API shrinker: convert superblock shrinkers to new API list: add a new LRU list type inode: convert inode lru list to generic lru list code. dcache: convert to use new lru list infrastructure list_lru: per-node list infrastructure shrinker: add node awareness fs: convert inode and dentry shrinking to be node aware xfs: convert buftarg LRU to generic code xfs: rework buffer dispose list tracking xfs: convert dquot cache lru to list_lru fs: convert fs shrinkers to new scan/count API drivers: convert shrinkers to new count/scan API shrinker: convert remaining shrinkers to count/scan API shrinker: Kill old ->shrink API. Glauber Costa (7): fs: bump inode and dentry counters to long super: fix calculation of shrinkable objects for small numbers list_lru: per-node API vmscan: per-node deferred work i915: bail out earlier when shrinker cannot acquire mutex hugepage: convert huge zero page shrinker to new shrinker API list_lru: dynamically adjust node arrays This patch: There are situations in very large machines in which we can have a large quantity of dirty inodes, unused dentries, etc. This is particularly true when umounting a filesystem, where eventually since every live object will eventually be discarded. Dave Chinner reported a problem with this while experimenting with the shrinker revamp patchset. So we believe it is time for a change. This patch just moves int to longs. Machines where it matters should have a big long anyway. Signed-off-by: Glauber Costa <glommer@openvz.org> Cc: Dave Chinner <dchinner@redhat.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dave Chinner <dchinner@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10Add missing unlocks to error paths of mountpoint_last.Dave Jones
Signed-off-by: Dave Jones <davej@fedoraproject.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10... and fold the renamed __vfs_follow_link() into its only callerAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10fs: remove vfs_follow_linkChristoph Hellwig
For a long time no filesystem has been using vfs_follow_link, and as seen by recent filesystem submissions any new use is accidental as well. Remove vfs_follow_link, document the replacement in Documentation/filesystems/porting and also rename __vfs_follow_link to match its only caller better. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10ARM: fix forced-HZ valuesRussell King
Olof Johansson reports that the tests against HZ_FIXED seem non-functional. Fix this by using '0' as a sentinel for "not specified" and test against that instead. Reported-by: Olof Johansson <olof@lixom.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-09-10[SCSI] lpfc 8.3.42: Fixed not able to log informational messages at early ↵James Smart
stage of driver init time Signed-off-by: James Smart <james.smart@emulex.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-09-10[SCSI] lpfc 8.3.42: Fixed using unsafe linked list macro for walking and ↵James Smart
deleting linked list Signed-off-by: James Smart <james.smart@emulex.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-09-10[SCSI] megaraid_sas: addded support for big endian architectureSumit.Saxena@lsi.com
This patch will add big endian architecture support to megaraid_sas driver. The support added is for LSI MegaRAID all generation controllers- (3Gb/s, 6Gb/s and 12 Gb/s controllers). We have done basic sanity test @ppc64 arch and @x86_64. Additional testing/observations are welcome. [jejb: fix up rejections] Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com> Signed-off-by: Sumit Saxena <sumit.saxena@lsi.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-09-10Merge tag 'cris-for-3.12' of git://jni.nu/crisLinus Torvalds
Pull CRIS updates from Jesper Nilsson: "Mostly cleanup and removal of unused configs" * tag 'cris-for-3.12' of git://jni.nu/cris: CRIS: drop unused Kconfig symbols CRIS: Add kvm_para.h which includes generic file CRIS: remove unused current_regs CRIS: Remove last traces of legacy RTC drivers CRIS: remove "config OOM_REBOOT"
2013-09-10mn10300: Fix crash just after starting userspace on !CONFIG_PREEMPTAkira Takeuchi
The mn10300 kernel crashes just after starting userspace programs, if CONFIG_PREEMPT is disabled: Freeing unused kernel memory: 96K (90286000 - 9029e000) MISALIGN: 97c33ff9: unsupported instruction f MISALIGN: 97c33ff9: unsupported instruction f MISALIGN: 97c33ff9: unsupported instruction f : This fixes the problem that was introduced by commit d17fc238ac14 ("MN10300: Enable IRQs more in system call exit work path"). Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com> Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-10[SCSI] aic7xxx: fix swapped arguments in ahc_find_pci_deviceDave Jones
The prototype for ahc_9005_subdevinfo_valid shows that the caller has the arguments in the wrong order. 637 ahc_9005_subdevinfo_valid(uint16_t device, uint16_t vendor, 638 uint16_t subdevice, uint16_t subvendor) Signed-off-by: Dave Jones <davej@fedoraproject.org> Acked-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-09-10[SCSI] hpsa: bump driver version to reflect changesMike Miller
Changes the version of hpsa so we know something has changed. Please consider this for inclusion. Signed-off-by: Mike Miller <mike.miller@hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-09-10[SCSI] hpsa: housekeeping patch for device_id and product arraysMike Miller
This patch does a bit of housekeeping for hpsa. Change lowercase alpha hex digits to uppercase for consistency within the driver. Also moves the P822se in the tables to keep controllers of each family grouped together. Signed-off-by: Mike Miller <mike.miller@hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-09-10[SCSI] hpsa: add HP Smart Array Gen8 namesMike Miller
Add the marketing names for HP Smart Array Gen8 controllers. Also removes an unused ID. Please consider this for inclusion. Signed-off-by: Mike Miller <mike.miller@hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-09-10i2c: davinci: Fix bad dev_get_platdata() conversionOlof Johansson
commit 6d4028c644e (i2c: use dev_get_platdata()) did a bad conversion of this one case: drivers/i2c/busses/i2c-davinci.c: In function 'davinci_i2c_probe': drivers/i2c/busses/i2c-davinci.c:665:2: warning: passing argument 1 of 'dev_get_platdata' from incompatible pointer type [enabled by default] Reviewed-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Olof Johansson <olof@lixom.net>
2013-09-10Merge branch 'pm-cpuidle'Rafael J. Wysocki
* pm-cpuidle: cpuidle: Check the result of cpuidle_get_driver() against NULL
2013-09-10Merge branch 'acpi-assorted'Rafael J. Wysocki
* acpi-assorted: ACPI / LPSS: don't crash if a device has no MMIO resources
2013-09-10Merge branch 'acpica'Rafael J. Wysocki
* acpica: ACPICA: Fix for a Store->ArgX when ArgX contains a reference to a field.
2013-09-10Merge branch 'acpi-pci-hotplug'Rafael J. Wysocki
* acpi-pci-hotplug: ACPI / hotplug / PCI: Avoid parent bus rescans on spurious device checks ACPI / hotplug / PCI: Use _OST to notify firmware about notify status ACPI / hotplug / PCI: Avoid doing too much for spurious notifies ACPI / hotplug / PCI: Don't trim devices before scanning the namespace
2013-09-10Merge branch 'acpi-hotplug'Rafael J. Wysocki
* acpi-hotplug: PM / hibernate / memory hotplug: Rework mutual exclusion PM / hibernate: Create memory bitmaps after freezing user space ACPI / scan: Change ordering of locks for device hotplug
2013-09-10[SCSI] hpsa: add HP Smart Array Gen9 PCI ID'sMike Miller
This patch adds the PCI ID's for HP Smart Array Gen9 controllers. Please consider this patch for inclusion. Signed-off-by: Mike Miller <mike.miller@hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-09-10intel_pstate: Add Haswell CPU modelsNell Hardcastle
Enable the intel_pstate driver for Haswell CPUs. One missing Ivy Bridge model (0x3E) is also included. Models referenced from tools/power/x86/turbostat/turbostat.c:has_nehalem_turbo_ratio_limit Signed-off-by: Nell Hardcastle <nell@spicious.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Dirk Brandewie <dirk.j.brandewie@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10Add missing unlocks to error paths of mountpoint_last.Dave Jones
Signed-off-by: Dave Jones <davej@fedoraproject.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10... and fold the renamed __vfs_follow_link() into its only callerAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10fs: remove vfs_follow_linkChristoph Hellwig
For a long time no filesystem has been using vfs_follow_link, and as seen by recent filesystem submissions any new use is accidental as well. Remove vfs_follow_link, document the replacement in Documentation/filesystems/porting and also rename __vfs_follow_link to match its only caller better. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linuxLinus Torvalds
Pull device tree core updates from Grant Likely: "Generally minor changes. A bunch of bug fixes, particularly for initialization and some refactoring. Most notable change if feeding the entire flattened tree into the random pool at boot. May not be significant, but shouldn't hurt either" Tim Bird questions whether the boot time cost of the random feeding may be noticeable. And "add_device_randomness()" is definitely not some speed deamon of a function. * tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux: of/platform: add error reporting to of_amba_device_create() irq/of: Fix comment typo for irq_of_parse_and_map of: Feed entire flattened device tree into the random pool of/fdt: Clean up casting in unflattening path of/fdt: Remove duplicate memory clearing on FDT unflattening gpio: implement gpio-ranges binding document fix of: call __of_parse_phandle_with_args from of_parse_phandle of: introduce of_parse_phandle_with_fixed_args of: move of_parse_phandle() of: move documentation of of_parse_phandle_with_args of: Fix missing memory initialization on FDT unflattening of: consolidate definition of early_init_dt_alloc_memory_arch() of: Make of_get_phy_mode() return int i.s.o. const int include: dt-binding: input: create a DT header defining key codes. of/platform: Staticize of_platform_device_create_pdata() of: Specify initrd location using 64-bit dt: Typo fix OF: make of_property_for_each_{u32|string}() use parameters if OF is not enabled
2013-09-10Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dmaLinus Torvalds
Pull slave-dmaengine updates from Vinod Koul: "This pull brings: - Andy's DW driver updates - Guennadi's sh driver updates - Pl08x driver fixes from Tomasz & Alban - Improvements to mmp_pdma by Daniel - TI EDMA fixes by Joel - New drivers: - Hisilicon k3dma driver - Renesas rcar dma driver - New API for publishing slave driver capablities - Various fixes across the subsystem by Andy, Jingoo, Sachin etc..." * 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma: (94 commits) dma: edma: Remove limits on number of slots dma: edma: Leave linked to Null slot instead of DUMMY slot dma: edma: Find missed events and issue them ARM: edma: Add function to manually trigger an EDMA channel dma: edma: Write out and handle MAX_NR_SG at a given time dma: edma: Setup parameters to DMA MAX_NR_SG at a time dmaengine: pl330: use dma_set_max_seg_size to set the sg limit dmaengine: dma_slave_caps: remove sg entries dma: replace devm_request_and_ioremap by devm_ioremap_resource dma: ste_dma40: Fix potential null pointer dereference dma: ste_dma40: Remove duplicate const dma: imx-dma: Remove redundant NULL check dma: dmagengine: fix function names in comments dma: add driver for R-Car HPB-DMAC dma: k3dma: use devm_ioremap_resource() instead of devm_request_and_ioremap() dma: imx-sdma: Staticize sdma_driver_data structures pch_dma: Add MODULE_DEVICE_TABLE dmaengine: PL08x: Add cyclic transfer support dmaengine: PL08x: Fix reading the byte count in cctl dmaengine: PL08x: Add support for different maximum transfer size ...
2013-09-10Merge tag 'mmc-updates-for-3.12-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc Pull MMC updates from Chris Ball: "MMC highlights for 3.12: Core: - Support Allocation Units 8MB-64MB in SD3.0, previous max was 4MB. - The slot-gpio helper can now handle GPIO debouncing card-detect. - Read supported voltages from DT "voltage-ranges" property. Drivers: - dw_mmc: Add support for ARC architecture, and support exynos5420. - mmc_spi: Support CD/RO GPIOs. - sh_mobile_sdhi: Add compatibility for more Renesas SoCs. - sh_mmcif: Add DT support for DMA channels" * tag 'mmc-updates-for-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: (50 commits) Revert "mmc: tmio-mmc: Remove .set_pwr() callback from platform data" mmc: dw_mmc: Add support for ARC mmc: sdhci-s3c: initialize host->quirks2 for using quirks2 mmc: sdhci-s3c: fix the wrong register value, when clock is disabled mmc: esdhc: add support to get voltage from device-tree mmc: sdhci: get voltage from sdhc host mmc: core: parse voltage from device-tree mmc: omap_hsmmc: use the generic config for omap2plus devices mmc: omap_hsmmc: clear status flags before starting a new command mmc: dw_mmc: exynos: Add a new compatible string for exynos5420 mmc: sh_mmcif: revision-specific CLK_CTRL2 handling mmc: sh_mmcif: revision-specific Command Completion Signal handling mmc: sh_mmcif: add support for Device Tree DMA bindings mmc: sh_mmcif: move header include from header into .c mmc: SDHI: add DT compatibility strings for further SoCs mmc: dw_mmc-pci: enable bus-mastering mode mmc: dw_mmc-pci: get resources from a proper BAR mmc: tmio-mmc: Remove .set_pwr() callback from platform data mmc: tmio-mmc: Remove .get_cd() callback from platform data mmc: sh_mobile_sdhi: Remove .set_pwr() callback from platform data ...
2013-09-10Merge tag 'dm-3.12-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device-mapper updates from Mike Snitzer: "Add the ability to collect I/O statistics on user-defined regions of a device-mapper device. This dm-stats code required the reintroduction of a div64_u64_rem() helper, but as a separate method that doesn't slow down div64_u64() -- especially on 32-bit systems. Allow the error target to replace request-based DM devices (e.g. multipath) in addition to bio-based DM devices. Various other small code fixes and improvements to thin-provisioning, DM cache and the DM ioctl interface" * tag 'dm-3.12-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm stripe: silence a couple sparse warnings dm: add statistics support dm thin: always return -ENOSPC if no_free_space is set dm ioctl: cleanup error handling in table_load dm ioctl: increase granularity of type_lock when loading table dm ioctl: prevent rename to empty name or uuid dm thin: set pool read-only if breaking_sharing fails block allocation dm thin: prefix pool error messages with pool device name dm: allow error target to replace bio-based and request-based targets math64: New separate div64_u64_rem helper dm space map: optimise sm_ll_dec and sm_ll_inc dm btree: prefetch child nodes when walking tree for a dm_btree_del dm btree: use pop_frame in dm_btree_del to cleanup code dm cache: eliminate holes in cache structure dm cache: fix stacking of geometry limits dm thin: fix stacking of geometry limits dm thin: add data block size limits to Documentation dm cache: add data block size limits to code and Documentation dm cache: document metadata device is exclussive to a cache dm: stop using WQ_NON_REENTRANT
2013-09-10Merge tag 'md/3.12' of git://neil.brown.name/mdLinus Torvalds
Pull md update from Neil Brown: "Headline item is multithreading for RAID5 so that more IO/sec can be supported on fast (SSD) devices. Also TILE-Gx SIMD suppor for RAID6 calculations and an assortment of bug fixes" * tag 'md/3.12' of git://neil.brown.name/md: raid5: only wakeup necessary threads md/raid5: flush out all pending requests before proceeding with reshape. md/raid5: use seqcount to protect access to shape in make_request. raid5: sysfs entry to control worker thread number raid5: offload stripe handle to workqueue raid5: fix stripe release order raid5: make release_stripe lockless md: avoid deadlock when dirty buffers during md_stop. md: Don't test all of mddev->flags at once. md: Fix apparent cut-and-paste error in super_90_validate raid6/test: replace echo -e with printf RAID: add tilegx SIMD implementation of raid6 md: fix safe_mode buglet. md: don't call md_allow_write in get_bitmap_file.
2013-09-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile 3 (of many) from Al Viro: "Waiman's conversion of d_path() and bits related to it, kern_path_mountpoint(), several cleanups and fixes (exportfs one is -stable fodder, IMO). There definitely will be more... ;-/" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: split read_seqretry_or_unlock(), convert d_walk() to resulting primitives dcache: Translating dentry into pathname without taking rename_lock autofs4 - fix device ioctl mount lookup introduce kern_path_mountpoint() rename user_path_umountat() to user_path_mountpoint_at() take unlazy_walk() into umount_lookup_last() Kill indirect include of file.h from eventfd.h, use fdget() in cgroup.c prune_super(): sb->s_op is never NULL exportfs: don't assume that ->iterate() won't feed us too long entries afs: get rid of redundant ->d_name.len checks
2013-09-10watchdog: s3c2410_wdt: simplify use of devm_ioremap_resourceJulia Lawall
Remove unneeded error handling on the result of a call to platform_get_resource when the value is passed to devm_ioremap_resource. Move the call to platform_get_resource adjacent to the call to devm_ioremap_resource to make the connection between them more clear. A simplified version of the semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression pdev,res,n,e,e1; expression ret != 0; identifier l; @@ - res = platform_get_resource(pdev, IORESOURCE_MEM, n); ... when != res - if (res == NULL) { ... \(goto l;\|return ret;\) } ... when != res + res = platform_get_resource(pdev, IORESOURCE_MEM, n); e = devm_ioremap_resource(e1, res); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2013-09-10watchdog: simplify platform_get_resource_byname/devm_ioremap_resourceJulia Lawall
Remove unneeded error handling on the result of a call to platform_get_resource_byname when the value is passed to devm_ioremap_resource. A simplified version of the semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression pdev,res,e,e1; expression ret != 0; identifier l; @@ res = platform_get_resource_byname(...); - if (res == NULL) { ... \(goto l;\|return ret;\) } e = devm_ioremap_resource(e1, res); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2013-09-10vfs: make sure we don't have a stale root path if unlazy_walk() failsLinus Torvalds
When I moved the RCU walk termination into unlazy_walk(), I didn't copy quite all of it: for the successful RCU termination we properly add the necessary reference counts to our temporary copy of the root path, but for the failure case we need to make sure that any temporary root path information is cleared out (since it does _not_ have the proper reference counts from the RCU lookup). We could clean up this mess by just always dropping the temporary root information, but Al points out that that would mean that a single lookup through symlinks could see multiple different root entries if it races with another thread doing chroot. Not that I think we should really care (we had that before too, back before we had a copy of the root path in the nameidata). Al says he has a cunning plan. In the meantime, this is the minimal fix for the problem, even if it's not all that pretty. Reported-by: Mace Moneta <moneta.mace@gmail.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-10watchdog: ts72xx_wdt: simplify use of devm_ioremap_resourceJulia Lawall
Remove unneeded error handling on the result of a call to platform_get_resource when the value is passed to devm_ioremap_resource. A simplified version of the semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression pdev,res,n,e,e1; expression ret != 0; identifier l; @@ - res = platform_get_resource(pdev, IORESOURCE_MEM, n); ... when != res - if (res == NULL) { ... \(goto l;\|return ret;\) } ... when != res + res = platform_get_resource(pdev, IORESOURCE_MEM, n); e = devm_ioremap_resource(e1, res); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2013-09-10watchdog: nuc900_wdt.c: simplify use of devm_ioremap_resourceJulia Lawall
Remove unneeded error handling on the result of a call to platform_get_resource when the value is passed to devm_ioremap_resource. A simplified version of the semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression pdev,res,n,e,e1; expression ret != 0; identifier l; @@ - res = platform_get_resource(pdev, IORESOURCE_MEM, n); ... when != res - if (res == NULL) { ... \(goto l;\|return ret;\) } ... when != res + res = platform_get_resource(pdev, IORESOURCE_MEM, n); e = devm_ioremap_resource(e1, res); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Wan Zongshun <mcuos.com@gmail.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2013-09-10watchdog: sunxi: New watchdog driver for Allwinner A10/A13Carlo Caione
This patch adds the driver for the watchdog found in the Allwinner A10 and A13 SoCs. It has DT-support and uses the new watchdog framework. Signed-off-by: Carlo Caione <carlo.caione@gmail.com> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2013-09-10watchdog: s3c2410_wdt: remove the global variablesLeela Krishna Amudala
This patch removes the global variables in the driver file and group them into a structure. Signed-off-by: Leela Krishna Amudala <l.krishna@samsung.com> Reviewed-by: Tomasz Figa <t.figa@samsung.com> Acked-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>