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2015-08-18blkcg: inline [__]blkg_lookup()Tejun Heo
blkg_lookup() checks whether the target queue is bypassing and, if not, calls __blkg_lookup() which first checks the lookup hint and then performs radix tree walk. The operations upto hint checking are trivial and there are many users of this function. This patch inlines blkg_lookup() and the fast path part of __blkg_lookup(). The radix tree lookup and hint update are now in blkg_lookup_slowpath(). This will help consolidating blkg handling by easing moving root blkcg short-circuit to inlined lookup fast path. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blkcg: replace blkcg_policy->cpd_size with ->cpd_alloc/free_fn() methodsTejun Heo
Each active policy has a cpd (blkcg_policy_data) on each blkcg. The cpd's were allocated by blkcg core and each policy could request to allocate extra space at the end by setting blkcg_policy->cpd_size larger than the size of cpd. This is a bit unusual but blkg (blkcg_gq) policy data used to be handled this way too so it made sense to be consistent; however, blkg policy data switched to alloc/free callbacks. This patch makes similar changes to cpd handling. blkcg_policy->cpd_alloc/free_fn() are added to replace ->cpd_size. As cpd allocation is now done from policy side, it can simply allocate a larger area which embeds cpd at the beginning. As ->cpd_alloc_fn() may be able to perform all necessary initializations, this patch makes ->cpd_init_fn() optional. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blkcg: minor updates around blkcg_policy_dataTejun Heo
* Rename blkcg->pd[] to blkcg->cpd[] so that cpd is consistently used for blkcg_policy_data. * Make blkcg_policy->cpd_init_fn() take blkcg_policy_data instead of blkcg. This makes it consistent with blkg_policy_data methods and to-be-added cpd alloc/free methods. * blkcg_policy_data->blkcg and cpd_to_blkcg() added so that cpd_init_fn() can determine the associated blkcg from blkcg_policy_data. v2: blkcg_policy_data->blkcg initializations were missing. Added. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blkcg: make blkcg_policy methods take a pointer to blkcg_policy_dataTejun Heo
The newly added ->pd_alloc_fn() and ->pd_free_fn() deal with pd (blkg_policy_data) while the older ones use blkg (blkcg_gq). As using blkg doesn't make sense for ->pd_alloc_fn() and after allocation pd can always be mapped to blkg and given that these are policy-specific methods, it makes sense to converge on pd. This patch makes all methods deal with pd instead of blkg. Most conversions are trivial. In blk-cgroup.c, a couple method invocation sites now test whether pd exists instead of policy state for consistency. This shouldn't cause any behavioral differences. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blk-throttle: clean up blkg_policy_data alloc/init/exit/free methodsTejun Heo
With the recent addition of alloc and free methods, things became messier. This patch reorganizes them according to the followings. * ->pd_alloc_fn() Responsible for allocation and static initializations - the ones which can be done independent of where the pd might be attached. * ->pd_init_fn() Initializations which require the knowledge of where the pd is attached. * ->pd_free_fn() The counter part of pd_alloc_fn(). Static de-init and freeing. This leaves ->pd_exit_fn() without any users. Removed. While at it, collapse an one liner function throtl_pd_exit(), which has only one user, into its user. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blk-throttle: remove asynchrnous percpu stats allocation mechanismTejun Heo
Because percpu allocator couldn't do non-blocking allocations, blk-throttle was forced to implement an ad-hoc asynchronous allocation mechanism for its percpu stats for cases where blkg's (blkcg_gq's) are allocated from an IO path without sleepable context. Now that percpu allocator can handle gfp_mask and blkg_policy_data alloc / free are handled by policy methods, the ad-hoc asynchronous allocation mechanism can be replaced with direct allocation from tg_stats_alloc_fn(). Rit it out. This ensures that an active throtl_grp always has valid non-NULL ->stats_cpu. Remove checks on it. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blkcg: replace blkcg_policy->pd_size with ->pd_alloc/free_fn() methodsTejun Heo
A blkg (blkcg_gq) represents the relationship between a cgroup and request_queue. Each active policy has a pd (blkg_policy_data) on each blkg. The pd's were allocated by blkcg core and each policy could request to allocate extra space at the end by setting blkcg_policy->pd_size larger than the size of pd. This is a bit unusual but was done this way mostly to simplify error handling and all the existing use cases could be handled this way; however, this is becoming too restrictive now that percpu memory can be allocated without blocking. This introduces two new mandatory blkcg_policy methods - pd_alloc_fn() and pd_free_fn() - which are used to allocate and release pd for a given policy. As pd allocation is now done from policy side, it can simply allocate a larger area which embeds pd at the beginning. This change makes ->pd_size pointless. Removed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blkcg: make blkcg_activate_policy() allow NULL ->pd_init_fnTejun Heo
blkg_create() allows NULL ->pd_init_fn() but blkcg_activate_policy() doesn't. As both in-kernel policies implement ->pd_init_fn, it currently doesn't break anything. Update blkcg_activate_policy() so that its behavior is consistent with blkg_create(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blkcg: restructure blkg_policy_data allocation in blkcg_activate_policy()Tejun Heo
When a policy gets activated, it needs to allocate and install its policy data on all existing blkg's (blkcg_gq's). Because blkg iteration is protected by a spinlock, it currently counts the total number of blkg's in the system, allocates the matching number of policy data on a list and installs them during a single iteration. This can be simplified by using speculative GFP_NOWAIT allocations while iterating and falling back to a preallocated policy data on failure. If the preallocated one has already been consumed, it releases the lock, preallocate with GFP_KERNEL and then restarts the iteration. This can be a bit more expensive than before but policy activation is a very cold path and shouldn't matter. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blkcg: remove unnecessary blkcg_root handling from css_alloc/free pathsTejun Heo
blkcg_css_alloc() bypasses policy data allocation and blkcg_css_free() bypasses policy data and blkcg freeing for blkcg_root. There's no reason to to treat policy data any differently for blkcg_root. If the root css gets allocated after policies are registered, policy registration path will add policy data; otherwise, the alloc path will. The free path isn't never invoked for root csses. This patch removes the unnecessary special handling of blkcg_root from css_alloc/free paths. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blkcg: use blkg_free() in blkcg_init_queue() failure pathTejun Heo
When blkcg_init_queue() fails midway after creating a new blkg, it performs kfree() directly; however, this doesn't free the policy data areas. Make it use blkg_free() instead. In turn, blkg_free() is updated to handle root request_list special case. While this fixes a possible memory leak, it's on an unlikely failure path of an already cold path and the size leaked per occurrence is miniscule too. I don't think it needs to be tagged for -stable. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blkcg: remove unnecessary request_list->blkg NULL test in blk_put_rl()Tejun Heo
Since ec13b1d6f0a0 ("blkcg: always create the blkcg_gq for the root blkcg"), a request_list always has its blkg associated. Drop unnecessary rl->blkg NULL test from blk_put_rl(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18cfq-iosched: charge async IOs to the appropriate blkcg's instead of the rootTejun Heo
Up until now, all async IOs were queued to async queues which are shared across the whole request_queue, which means that blkcg resource control is completely void on async IOs including all writeback IOs. It was done this way because writeback didn't support writeback and there was no way of telling which writeback IO belonged to which cgroup; however, writeback recently became cgroup aware and writeback bio's are sent down properly tagged with the blkcg's to charge them against. This patch makes async cfq_queues per-cfq_cgroup instead of per-cfq_data so that each async IO is charged to the blkcg that it was tagged for instead of unconditionally attributing it to root. * cfq_data->async_cfqq and ->async_idle_cfqq are moved to cfq_group and alloc / destroy paths are updated accordingly. * cfq_link_cfqq_cfqg() no longer overrides @cfqg to root for async queues. * check_blkcg_changed() now also invalidates async queues as they no longer stay the same across cgroups. After this patch, cfq's proportional IO control through blkio.weight works correctly when cgroup writeback is in use. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18cfq-iosched: fold cfq_find_alloc_queue() into cfq_get_queue()Tejun Heo
cfq_find_alloc_queue() checks whether a queue actually needs to be allocated, which is unnecessary as its sole caller, cfq_get_queue(), only calls it if so. Also, the oom queue fallback logic is scattered between cfq_get_queue() and cfq_find_alloc_queue(). There really isn't much going on in the latter and things can be made simpler by folding it into cfq_get_queue(). This patch collapses cfq_find_alloc_queue() into cfq_get_queue(). The change is fairly straight-forward with one exception - async_cfqq is now initialized to NULL and the "!is_sync" test in the last if conditional is replaced with "async_cfqq" test. This is because gcc (5.1.1) gets confused for some reason and warns that async_cfqq may be used uninitialized otherwise. Oh well, the code isn't necessarily worse this way. This patch doesn't cause any functional difference. v2: Updated to reflect GFP_ATOMIC -> GPF_NOWAIT. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18cfq-iosched: move cfq_group determination from cfq_find_alloc_queue() to ↵Tejun Heo
cfq_get_queue() This is necessary for making async cfq_cgroups per-cfq_group instead of per-cfq_data. While this change makes cfq_get_queue() perform RCU locking and look up cfq_group even when it reuses async queue, the extra overhead is extremely unlikely to be noticeable given that this is already sitting behind cic->cfqq[] cache and the overall cost of cfq operation. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18cfq-iosched: remove @gfp_mask from cfq_find_alloc_queue()Tejun Heo
Even when allocations fail, cfq_find_alloc_queue() always returns a valid cfq_queue by falling back to the oom cfq_queue. As such, there isn't much point in taking @gfp_mask and trying "harder" if __GFP_WAIT is set. GFP_NOWAIT allocations don't fail often and even when they do the degraded behavior is acceptable and temporary. After all, the only reason get_request(), which ultimately determines the gfp_mask, cares about __GFP_WAIT is to guarantee request allocation, assuming IO forward progress, for callers which are willing to wait. There's no reason for cfq_find_alloc_queue() to behave differently on __GFP_WAIT when it already has a fallback mechanism. Remove @gfp_mask from cfq_find_alloc_queue() and propagate the changes to its callers. This simplifies the function quite a bit and will help making async queues per-cfq_group. v2: Updated to reflect GFP_ATOMIC -> GPF_NOWAIT. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18blkcg, cfq-iosched: use GFP_NOWAIT instead of GFP_ATOMIC for non-critical ↵Tejun Heo
allocations blkcg performs several allocations to track IOs per cgroup and enforce resource control. Most of these allocations are performed lazily on demand in the IO path and thus can't involve reclaim path. Currently, these allocations use GFP_ATOMIC; however, blkcg can gracefully deal with occassional failures of these allocations by punting IOs to the root cgroup and there's no reason to reach into the emergency reserve. This patch replaces GFP_ATOMIC with GFP_NOWAIT for the following allocations. * bdi_writeback_congested and blkcg_gq allocations in blkg_create(). * radix tree node allocations for blkcg->blkg_tree. * cfq_queue allocation on ioprio changes. Signed-off-by: Tejun Heo <tj@kernel.org> Suggested-and-Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Suggested-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18cfq-iosched: minor cleanupsTejun Heo
* Some were accessing cic->cfqq[] directly. Always use cic_to_cfqq() and cic_set_cfqq(). * check_ioprio_changed() doesn't need to verify cfq_get_queue()'s return for NULL. It's always non-NULL. Simplify accordingly. This patch doesn't cause any functional changes. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18cfq-iosched: fix oom cfq_queue ref leak in cfq_set_request()Tejun Heo
If the cfq_queue cached in cfq_io_cq is the oom one, cfq_set_request() replaces it by invoking cfq_get_queue() again without putting the oom queue leaking the reference it was holding. While oom queues are not released through reference counting, they're still reference counted and this can theoretically lead to the reference count overflowing and incorrectly invoke the usual release path on it. Fix it by making cfq_set_request() put the ref it was holding. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18cfq-iosched: fix async oom queue handlingTejun Heo
Async cfqq's (cfq_queue's) are shared across cfq_data. When cfq_get_queue() obtains a new queue from cfq_find_alloc_queue(), it stashes the pointer in cfq_data and reuses it from then on; however, the function doesn't consider that cfq_find_alloc_queue() may return the oom_cfqq under memory pressure and installs the returned queue unconditionally. If the oom_cfqq is installed as an async cfqq, cfq_set_request() will continue calling cfq_get_queue() hoping to replace it with a proper queue; however, cfq_get_queue() will keep returning the cached queue for the slot - the oom_cfqq. Fix it by skipping caching if the queue is the oom one. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18cfq-iosched: simplify control flow in cfq_get_queue()Tejun Heo
cfq_get_queue()'s control flow looks like the following. async_cfqq = NULL; cfqq = NULL; if (!is_sync) { ... async_cfqq = ...; cfqq = *async_cfqq; } if (!cfqq) cfqq = ...; if (!is_sync && !(*async_cfqq)) ...; The only thing the local variable init, the second if, and the async_cfqq test in the third if achieves is to skip cfqq creation and installation if *async_cfqq was already non-NULL. This is needlessly complicated with different tests examining the same condition. Simplify it to the following. if (!is_sync) { ... async_cfqq = ...; cfqq = *async_cfqq; if (cfqq) goto out; } cfqq = ...; if (!is_sync) ...; out: Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18writeback: update writeback tracepoints to report cgroupTejun Heo
The following tracepoints are updated to report the cgroup used during cgroup writeback. * writeback_write_inode[_start] * writeback_queue * writeback_exec * writeback_start * writeback_written * writeback_wait * writeback_nowork * writeback_wake_background * wbc_writepage * writeback_queue_io * bdi_dirty_ratelimit * balance_dirty_pages * writeback_sb_inodes_requeue * writeback_single_inode[_start] Note that writeback_bdi_register is separated out from writeback_class as reporting cgroup doesn't make sense to it. Tracepoints which take bdi are updated to take bdi_writeback instead. Signed-off-by: Tejun Heo <tj@kernel.org> Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18kernfs: implement kernfs_path_len()Tejun Heo
Add a function to determine the path length of a kernfs node. This for now will be used by writeback tracepoint updates. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18writeback: explain why @inode is allowed to be NULL for inode_congested()Tejun Heo
Signed-off-by: Tejun Heo <tj@kernel.org> Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18writeback: remove wb_writeback_work->single_wait/doneTejun Heo
wb_writeback_work->single_wait/done are used for the wait mechanism for synchronous wb_work (wb_writeback_work) items which are issued when bdi_split_work_to_wbs() fails to allocate memory for asynchronous wb_work items; however, there's no reason to use a separate wait mechanism for this. bdi_split_work_to_wbs() can simply use on-stack fallback wb_work item and separate wb_completion to wait for it. This patch removes wb_work->single_wait/done and the related code and make bdi_split_work_to_wbs() use on-stack fallback wb_work and wb_completion instead. Signed-off-by: Tejun Heo <tj@kernel.org> Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18writeback: bdi_for_each_wb() iteration is memcg ID based not blkcgTejun Heo
wb's (bdi_writeback's) are currently keyed by memcg ID; however, in an earlier implementation, wb's were keyed by blkcg ID. bdi_for_each_wb() walks bdi->cgwb_tree in the ascending ID order and allows iterations to start from an arbitrary ID which is used to interrupt and resume iterations. Unfortunately, while changing wb to be keyed by memcg ID instead of blkcg, bdi_for_each_wb() was missed and is still assuming that wb's are keyed by blkcg ID. This doesn't affect iterations which don't get interrupted but bdi_split_work_to_wbs() makes use of iteration resuming on allocation failures and thus may incorrectly skip or repeat wb's. Fix it by changing bdi_for_each_wb() to take memcg IDs instead of blkcg IDs and updating bdi_split_work_to_wbs() accordingly. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18Merge branch 'for-4.3-unified-base' of ↵Jens Axboe
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup into for-4.3/blkcg
2015-08-18cgroup: introduce cgroup_subsys->legacy_nameTejun Heo
This allows cgroup subsystems to use a different name on the unified hierarchy. cgroup_subsys->name is used on the unified hierarchy, ->legacy_name elsewhere. If ->legacy_name is not explicitly set, it's automatically set to ->name and the userland visible behavior remains unchanged. v2: Make parse_cgroupfs_options() only consider ->legacy_name as mount options are used only on legacy hierarchies. Suggested by Li Zefan. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: cgroups@vger.kernel.org
2015-08-18cgroup: don't print subsystems for the default hierarchyTejun Heo
It doesn't make sense to print subsystems on mount option or /proc/PID/cgroup for the default hierarchy. * cgroup.controllers file at the root of the default hierarchy lists the currently attached controllers. * The default hierarchy is catch-all for unmounted subsystems. * The default hierarchy doesn't accept any mount options. Suppress subsystem printing on mount options and /proc/PID/cgroup for the default hierarchy. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: cgroups@vger.kernel.org
2015-08-11cgroup: make cftype->private a unsigned longTejun Heo
It's pretty unusual to have an int as a private data field and it makes it impossible to carray a pointer value through it. Let's make it an unsigned long. AFAICS, this shouldn't break anything. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org>
2015-08-05cgroup: export cgrp_dfl_rootTejun Heo
While cgroup subsystems can't be modules, blkcg supports dynamically loadable policies which interact with cgroup core. Export cgrp_dfl_root so that cgroup_on_dfl() can be used in those modules. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org>
2015-08-04cgroup: define controller file conventionsTejun Heo
Traditionally, each cgroup controller implemented whatever interface it wanted leading to interfaces which are widely inconsistent. Examining the requirements of the controllers readily yield that there are only a few control schemes shared among all. Two major controllers already had to implement new interface for the unified hierarchy due to significant structural changes. Let's take the chance to establish common conventions throughout all controllers. This patch defines CGROUP_WEIGHT_MIN/DFL/MAX to be used on all weight based control knobs and documents the conventions that controllers should follow on the unified hierarchy. Except for io.weight knob, all existing unified hierarchy knobs are already compliant. A follow-up patch will update io.weight. v2: Added descriptions of min, low and high knobs. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Peter Zijlstra <peterz@infradead.org>
2015-07-27Merge branch 'stable/for-jens-4.2' of ↵Jens Axboe
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-linus Konrad writes: "There are three bugs that have been found in the xen-blkfront (and backend). Two of them have the stable tree CC-ed. They have been found where an guest is migrating to a host that is missing 'feature-persistent' support (from one that has it enabled). We end up hitting an BUG() in the driver code."
2015-07-26Linux 4.2-rc4Linus Torvalds
2015-07-26Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fix from Thomas Gleixner: "A single fix for the intel cqm perf facility to prevent IPIs from interrupt context" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel/cqm: Return cached counter value from IRQ context
2015-07-26Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "This update contains: - the manual revert of the SYSCALL32 changes which caused a regression - a fix for the MPX vma handling - three fixes for the ioremap 'is ram' checks. - PAT warning fixes - a trivial fix for the size calculation of TLB tracepoints - handle old EFI structures gracefully This also contains a PAT fix from Jan plus a revert thereof. Toshi explained why the code is correct" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm/pat: Revert 'Adjust default caching mode translation tables' x86/asm/entry/32: Revert 'Do not use R9 in SYSCALL32' commit x86/mm: Fix newly introduced printk format warnings mm: Fix bugs in region_is_ram() x86/mm: Remove region_is_ram() call from ioremap x86/mm: Move warning from __ioremap_check_ram() to the call site x86/mm/pat, drivers/media/ivtv: Move the PAT warning and replace WARN() with pr_warn() x86/mm/pat, drivers/infiniband/ipath: Replace WARN() with pr_warn() x86/mm/pat: Adjust default caching mode translation tables x86/fpu: Disable dependent CPU features on "noxsave" x86/mpx: Do not set ->vm_ops on MPX VMAs x86/mm: Add parenthesis for TLB tracepoint size calculation efi: Handle memory error structures produced based on old versions of standard
2015-07-26x86/mm/pat: Revert 'Adjust default caching mode translation tables'Thomas Gleixner
Toshi explains: "No, the default values need to be set to the fallback types, i.e. minimal supported mode. For WC and WT, UC is the fallback type. When PAT is disabled, pat_init() does update the tables below to enable WT per the default BIOS setup. However, when PAT is enabled, but CPU has PAT -errata, WT falls back to UC per the default values." Revert: ca1fec58bc6a 'x86/mm/pat: Adjust default caching mode translation tables' Requested-by: Toshi Kani <toshi.kani@hp.com> Cc: Jan Beulich <jbeulich@suse.de> Link: http://lkml.kernel.org/r/1437577776.3214.252.camel@hp.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-26perf/x86/intel/cqm: Return cached counter value from IRQ contextMatt Fleming
Peter reported the following potential crash which I was able to reproduce with his test program, [ 148.765788] ------------[ cut here ]------------ [ 148.765796] WARNING: CPU: 34 PID: 2840 at kernel/smp.c:417 smp_call_function_many+0xb6/0x260() [ 148.765797] Modules linked in: [ 148.765800] CPU: 34 PID: 2840 Comm: perf Not tainted 4.2.0-rc1+ #4 [ 148.765803] ffffffff81cdc398 ffff88085f105950 ffffffff818bdfd5 0000000000000007 [ 148.765805] 0000000000000000 ffff88085f105990 ffffffff810e413a 0000000000000000 [ 148.765807] ffffffff82301080 0000000000000022 ffffffff8107f640 ffffffff8107f640 [ 148.765809] Call Trace: [ 148.765810] <NMI> [<ffffffff818bdfd5>] dump_stack+0x45/0x57 [ 148.765818] [<ffffffff810e413a>] warn_slowpath_common+0x8a/0xc0 [ 148.765822] [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60 [ 148.765824] [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60 [ 148.765825] [<ffffffff810e422a>] warn_slowpath_null+0x1a/0x20 [ 148.765827] [<ffffffff811613f6>] smp_call_function_many+0xb6/0x260 [ 148.765829] [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60 [ 148.765831] [<ffffffff81161748>] on_each_cpu_mask+0x28/0x60 [ 148.765832] [<ffffffff8107f6ef>] intel_cqm_event_count+0x7f/0xe0 [ 148.765836] [<ffffffff811cdd35>] perf_output_read+0x2a5/0x400 [ 148.765839] [<ffffffff811d2e5a>] perf_output_sample+0x31a/0x590 [ 148.765840] [<ffffffff811d333d>] ? perf_prepare_sample+0x26d/0x380 [ 148.765841] [<ffffffff811d3497>] perf_event_output+0x47/0x60 [ 148.765843] [<ffffffff811d36c5>] __perf_event_overflow+0x215/0x240 [ 148.765844] [<ffffffff811d4124>] perf_event_overflow+0x14/0x20 [ 148.765847] [<ffffffff8107e7f4>] intel_pmu_handle_irq+0x1d4/0x440 [ 148.765849] [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0 [ 148.765853] [<ffffffff81219bad>] ? vunmap_page_range+0x19d/0x2f0 [ 148.765854] [<ffffffff81219d11>] ? unmap_kernel_range_noflush+0x11/0x20 [ 148.765859] [<ffffffff814ce6fe>] ? ghes_copy_tofrom_phys+0x11e/0x2a0 [ 148.765863] [<ffffffff8109e5db>] ? native_apic_msr_write+0x2b/0x30 [ 148.765865] [<ffffffff8109e44d>] ? x2apic_send_IPI_self+0x1d/0x20 [ 148.765869] [<ffffffff81065135>] ? arch_irq_work_raise+0x35/0x40 [ 148.765872] [<ffffffff811c8d86>] ? irq_work_queue+0x66/0x80 [ 148.765875] [<ffffffff81075306>] perf_event_nmi_handler+0x26/0x40 [ 148.765877] [<ffffffff81063ed9>] nmi_handle+0x79/0x100 [ 148.765879] [<ffffffff81064422>] default_do_nmi+0x42/0x100 [ 148.765880] [<ffffffff81064563>] do_nmi+0x83/0xb0 [ 148.765884] [<ffffffff818c7c0f>] end_repeat_nmi+0x1e/0x2e [ 148.765886] [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0 [ 148.765888] [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0 [ 148.765890] [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0 [ 148.765891] <<EOE>> [<ffffffff8110ab66>] finish_task_switch+0x156/0x210 [ 148.765898] [<ffffffff818c1671>] __schedule+0x341/0x920 [ 148.765899] [<ffffffff818c1c87>] schedule+0x37/0x80 [ 148.765903] [<ffffffff810ae1af>] ? do_page_fault+0x2f/0x80 [ 148.765905] [<ffffffff818c1f4a>] schedule_user+0x1a/0x50 [ 148.765907] [<ffffffff818c666c>] retint_careful+0x14/0x32 [ 148.765908] ---[ end trace e33ff2be78e14901 ]--- The CQM task events are not safe to be called from within interrupt context because they require performing an IPI to read the counter value on all sockets. And performing IPIs from within IRQ context is a "no-no". Make do with the last read counter value currently event in event->count when we're invoked in this context. Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vikas Shivappa <vikas.shivappa@intel.com> Cc: Kanaka Juvva <kanaka.d.juvva@intel.com> Cc: Will Auld <will.auld@intel.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1437490509-15373-1-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-25Merge tag 'usb-4.2-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB fixes from Greg KH: "Here's a few USB and PHY fixes for 4.2-rc4. Nothing major, the shortlog has the full details. All of these have been in linux-next successfully" * tag 'usb-4.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (21 commits) USB: OHCI: fix bad #define in ohci-tmio.c cdc-acm: Destroy acm_minors IDR on module exit usb-storage: Add ignore-device quirk for gm12u320 based usb mini projectors usb-storage: ignore ZTE MF 823 card reader in mode 0x1225 USB: OHCI: Fix race between ED unlink and URB submission usb: core: lpm: set lpm_capable for root hub device xhci: do not report PLC when link is in internal resume state xhci: prevent bus_suspend if SS port resuming in phase 1 xhci: report U3 when link is in resume state xhci: Calculate old endpoints correctly on device reset usb: xhci: Bugfix for NULL pointer deference in xhci_endpoint_init() function xhci: Workaround to get D3 working in Intel xHCI xhci: call BIOS workaround to enable runtime suspend on Intel Braswell usb: dwc3: Reset the transfer resource index on SET_INTERFACE usb: gadget: udc: core: Fix argument of dma_map_single for IOMMU usb: gadget: mv_udc_core: fix phy_regs I/O memory leak usb: ulpi: ulpi_init should be executed in subsys_initcall phy: berlin-usb: fix divider for BG2 phy: berlin-usb: fix divider for BG2CD phy/pxa: add HAS_IOMEM dependency ...
2015-07-25Merge tag 'tty-4.2-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver fixes from Greg KH: "Here are a number of small serial and tty fixes for reported issues. All have been in linux-next successfully" * tag 'tty-4.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: tty: vt: Fix !TASK_RUNNING diagnostic warning from paste_selection() serial: core: Fix crashes while echoing when closing m32r: Add ioreadXX/iowriteXX big-endian mmio accessors Revert "serial: imx: initialized DMA w/o HW flow enabled" sc16is7xx: fix FIFO address of secondary UART sc16is7xx: fix Kconfig dependencies serial: etraxfs-uart: Fix release etraxfs_uart_ports tty/vt: Fix the memory leak in visual_init serial: amba-pl011: Fix devm_ioremap_resource return value check n_tty: signal and flush atomically
2015-07-25Merge tag 'staging-4.2-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging Pull staging driver fixes from Greg KH: "Here are a number of iio and staging driver fixes for reported issues for 4.2-rc4. All have been in linux-next for a while with no problems" * tag 'staging-4.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (34 commits) iio:light:stk3310: make endianness independent of host iio:light:stk3310: move device register to end of probe iio: mma8452: use iio event type IIO_EV_TYPE_MAG iio: mcp320x: Fix NULL pointer dereference iio: adc: vf610: fix the adc register read fail issue iio: mlx96014: Replace offset sign iio: magnetometer: mmc35240: fix SET/RESET sequence iio: magnetometer: mmc35240: Fix SET/RESET mask iio: magnetometer: mmc35240: Fix crash in pm suspend iio:magnetometer:bmc150_magn: output intended variable iio:magnetometer:bmc150_magn: add regmap dependency staging: vt6656: check ieee80211_bss_conf bssid not NULL staging: vt6655: check ieee80211_bss_conf bssid not NULL iio: tmp006: Check channel info on write iio: sx9500: Add missing init in sx9500_buffer_pre{en,dis}able() iio:light:ltr501: fix regmap dependency iio:light:ltr501: fix variable in ltr501_init iio: sx9500: fix bug in compensation code iio: sx9500: rework error handling of raw readings iio: magnetometer: mmc35240: fix available sampling frequencies ...
2015-07-25Merge tag 'char-misc-4.2-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver fixes from Greg KH: "Here are some char and misc driver fixes for reported issues. One parport patch is reverted as it was incorrect, thanks to testing by the 0-day bot" * tag 'char-misc-4.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: parport: Revert "parport: fix memory leak" mei: prevent unloading mei hw modules while the device is opened. misc: mic: scif bug fix for vmalloc_to_page crash parport: fix freeing freed memory parport: fix memory leak parport: fix error handling
2015-07-25parport: Revert "parport: fix memory leak"Sudip Mukherjee
This reverts commit 23c405912b88 ("parport: fix memory leak") par_dev->state was already being removed in parport_unregister_device(). Reported-by: Ying Huang <ying.huang@intel.com> Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-07-25Merge tag 'trace-v4.2-rc2-fix3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull ftrace fix from Steven Rostedt: "Back in 3.16 the ftrace code was redesigned and cleaned up to remove the double iteration list (one for registered ftrace ops, and one for registered "global" ops), to just use one list. That simplified the code but also broke the function tracing filtering on pid. This updates the code to handle the filtering again with the new logic" * tag 'trace-v4.2-rc2-fix3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace: Fix breakage of set_ftrace_pid
2015-07-25Merge branch 'libnvdimm-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm Pull libnvdimm fix from Dan Williams: "A minor fix for the libnvdimm subsystem. This is not critical. The problem can be worked around in userspace by putting the namespace temporarily into raw mode (ndctl_namespace_set_raw_mode() from libndctl), but that is awkward for management utilities. * 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm: libnvdimm: fix namespace seed creation
2015-07-25Merge tag 'md/4.2-fixes' of git://neil.brown.name/mdLinus Torvalds
Pull md fixes from Neil Brown: "Some md fixes for 4.2 Several are tagged for -stable. A few aren't because they are not very, serious or because they are in the 'experimental' cluster code" * tag 'md/4.2-fixes' of git://neil.brown.name/md: md/raid5: clear R5_NeedReplace when no longer needed. Fix read-balancing during node failure md-cluster: fix bitmap sub-offset in bitmap_read_sb md: Return error if request_module fails and returns positive value md: Skip cluster setup in case of error while reading bitmap md/raid1: fix test for 'was read error from last working device'. md: Skip cluster setup for dm-raid md: flush ->event_work before stopping array. md/raid10: always set reshape_safe when initializing reshape_position. md/raid5: avoid races when changing cache size.
2015-07-25Merge tag 'for-linus-20150724' of git://git.infradead.org/linux-mtdLinus Torvalds
Pull MTD fixes from Brian Norris: "Two trivial updates. I meant to send these much earlier, but I've been preoccupied. - Add MAINTAINERS entry for diskonchip g3 driver - Fix an overlooked conflict in bitfield value assignments The latter update is a bit overdue, but there's no reason to wait any longer" * tag 'for-linus-20150724' of git://git.infradead.org/linux-mtd: mtd: nand: Fix NAND_USE_BOUNCE_BUFFER flag conflict MAINTAINERS: mtd: docg3: add docg3 maintainer
2015-07-25libnvdimm: fix namespace seed creationDan Williams
A new BLK namespace "seed" device is created whenever the current seed is successfully probed. However, if that namespace is assigned to a BTT it may never directly experience a successful probe as it is a subordinate device to a BTT configuration. The effect of the current code is that no new namespaces can be instantiated, after the seed namespace, to consume available BLK DPA capacity. Fix this by treating a successful BTT probe event as a successful probe event for the backing namespace. Reported-by: Nicholas Moulin <nicholas.w.moulin@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-07-24Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: "Four smaller fixes for the current series. This contains: - A fix for clones of discard bio's, that can cause data corruption. From Martin. - A fix for null_blk, where in certain queue modes it could access a request after it had been freed. From Mike Krinkin. - An error handling leak fix for blkcg, from Tejun. - Also from Tejun, export of the functions that a file system needs to implement cgroup writeback support" * 'for-linus' of git://git.kernel.dk/linux-block: block: Do a full clone when splitting discard bios block: export bio_associate_*() and wbc_account_io() blkcg: fix gendisk reference leak in blkg_conf_prep() null_blk: fix use-after-free problem
2015-07-24Merge branch 'for-4.2-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata Pull libata fixes from Tejun Heo: "A couple important fixes. - A block layer change which removed restriction on max transfer size led to silent data corruption on some devices. A new quirk is added to restore the old size limit for the reported device. If it gets reported on more devices, we might have to consider restoring the restriction for ATA devices by default. - There finally is a SSD which is confirmed to cause data corruption on TRIM regardless of which flavor is used. A new quirk is added and the device is blacklisted - Other device-specific workarounds" * 'for-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata: libata: Do not blacklist M510DC libata: increase the timeout when setting transfer mode libata: add ATA_HORKAGE_MAX_SEC_1024 to revert back to previous max_sectors limit libata: force disable trim for SuperSSpeed S238 libata: add ATA_HORKAGE_NOTRIM libata: add ATA_HORKAGE_BROKEN_FPDMA_AA quirk for HP 250GB SATA disk VB0250EAVER ata: pmp: add quirk for Marvell 4140 SATA PMP