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* percpu: replace area map allocator with bitmapDennis Zhou (Facebook)2017-07-261-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The percpu memory allocator is experiencing scalability issues when allocating and freeing large numbers of counters as in BPF. Additionally, there is a corner case where iteration is triggered over all chunks if the contig_hint is the right size, but wrong alignment. This patch replaces the area map allocator with a basic bitmap allocator implementation. Each subsequent patch will introduce new features and replace full scanning functions with faster non-scanning options when possible. Implementation: This patchset removes the area map allocator in favor of a bitmap allocator backed by metadata blocks. The primary goal is to provide consistency in performance and memory footprint with a focus on small allocations (< 64 bytes). The bitmap removes the heavy memmove from the freeing critical path and provides a consistent memory footprint. The metadata blocks provide a bound on the amount of scanning required by maintaining a set of hints. In an effort to make freeing fast, the metadata is updated on the free path if the new free area makes a page free, a block free, or spans across blocks. This causes the chunk's contig hint to potentially be smaller than what it could allocate by up to the smaller of a page or a block. If the chunk's contig hint is contained within a block, a check occurs and the hint is kept accurate. Metadata is always kept accurate on allocation, so there will not be a situation where a chunk has a later contig hint than available. Evaluation: I have primarily done testing against a simple workload of allocation of 1 million objects (2^20) of varying size. Deallocation was done by in order, alternating, and in reverse. These numbers were collected after rebasing ontop of a80099a152. I present the worst-case numbers here: Area Map Allocator: Object Size | Alloc Time (ms) | Free Time (ms) ---------------------------------------------- 4B | 310 | 4770 16B | 557 | 1325 64B | 436 | 273 256B | 776 | 131 1024B | 3280 | 122 Bitmap Allocator: Object Size | Alloc Time (ms) | Free Time (ms) ---------------------------------------------- 4B | 490 | 70 16B | 515 | 75 64B | 610 | 80 256B | 950 | 100 1024B | 3520 | 200 This data demonstrates the inability for the area map allocator to handle less than ideal situations. In the best case of reverse deallocation, the area map allocator was able to perform within range of the bitmap allocator. In the worst case situation, freeing took nearly 5 seconds for 1 million 4-byte objects. The bitmap allocator dramatically improves the consistency of the free path. The small allocations performed nearly identical regardless of the freeing pattern. While it does add to the allocation latency, the allocation scenario here is optimal for the area map allocator. The area map allocator runs into trouble when it is allocating in chunks where the latter half is full. It is difficult to replicate this, so I present a variant where the pages are second half filled. Freeing was done sequentially. Below are the numbers for this scenario: Area Map Allocator: Object Size | Alloc Time (ms) | Free Time (ms) ---------------------------------------------- 4B | 4118 | 4892 16B | 1651 | 1163 64B | 598 | 285 256B | 771 | 158 1024B | 3034 | 160 Bitmap Allocator: Object Size | Alloc Time (ms) | Free Time (ms) ---------------------------------------------- 4B | 481 | 67 16B | 506 | 69 64B | 636 | 75 256B | 892 | 90 1024B | 3262 | 147 The data shows a parabolic curve of performance for the area map allocator. This is due to the memmove operation being the dominant cost with the lower object sizes as more objects are packed in a chunk and at higher object sizes, the traversal of the chunk slots is the dominating cost. The bitmap allocator suffers this problem as well. The above data shows the inability to scale for the allocation path with the area map allocator and that the bitmap allocator demonstrates consistent performance in general. The second problem of additional scanning can result in the area map allocator completing in 52 minutes when trying to allocate 1 million 4-byte objects with 8-byte alignment. The same workload takes approximately 16 seconds to complete for the bitmap allocator. V2: Fixed a bug in pcpu_alloc_first_chunk end_offset was setting the bitmap using bytes instead of bits. Added a comment to pcpu_cnt_pop_pages to explain bitmap_weight. Signed-off-by: Dennis Zhou <dennisszhou@gmail.com> Reviewed-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* random: do not ignore early device randomnessKees Cook2017-07-121-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | The add_device_randomness() function would ignore incoming bytes if the crng wasn't ready. This additionally makes sure to make an early enough call to add_latent_entropy() to influence the initial stack canary, which is especially important on non-x86 systems where it stays the same through the life of the boot. Link: http://lkml.kernel.org/r/20170626233038.GA48751@beast Signed-off-by: Kees Cook <keescook@chromium.org> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jessica Yu <jeyu@redhat.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Tejun Heo <tj@kernel.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Lokesh Vutla <lokeshvutla@ti.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: allow slab_nomerge to be set at build timeKees Cook2017-07-061-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some hardened environments want to build kernels with slab_nomerge already set (so that they do not depend on remembering to set the kernel command line option). This is desired to reduce the risk of kernel heap overflows being able to overwrite objects from merged caches and changes the requirements for cache layout control, increasing the difficulty of these attacks. By keeping caches unmerged, these kinds of exploits can usually only damage objects in the same cache (though the risk to metadata exploitation is unchanged). Link: http://lkml.kernel.org/r/20170620230911.GA25238@beast Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Daniel Micay <danielmicay@gmail.com> Cc: David Windsor <dave@nullcore.net> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Christoph Lameter <cl@linux.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Daniel Micay <danielmicay@gmail.com> Cc: David Windsor <dave@nullcore.net> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Tejun Heo <tj@kernel.org> Cc: Daniel Mack <daniel@zonque.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Helge Deller <deller@gmx.de> Cc: Rik van Riel <riel@redhat.com> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-4.13' of ↵Linus Torvalds2017-07-061-2/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup changes from Tejun Heo: - Waiman made the debug controller work and a lot more useful on cgroup2 - There were a couple issues with cgroup subtree delegation. The documentation on delegating to a non-root user was missing some part and cgroup namespace support wasn't factoring in delegation at all. The documentation is updated and the now there is a mount option to make cgroup namespace fit for delegation * 'for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: implement "nsdelegate" mount option cgroup: restructure cgroup_procs_write_permission() cgroup: "cgroup.subtree_control" should be writeable by delegatee cgroup: fix lockdep warning in debug controller cgroup: refactor cgroup_masks_read() in the debug controller cgroup: make debug an implicit controller on cgroup2 cgroup: Make debug cgroup support v2 and thread mode cgroup: Make Kconfig prompt of debug cgroup more accurate cgroup: Move debug cgroup to its own file cgroup: Keep accurate count of tasks in each css_set
| * cgroup: Make Kconfig prompt of debug cgroup more accurateWaiman Long2017-06-141-2/+5
| | | | | | | | | | | | | | | | | | The Kconfig prompt and description of the debug cgroup controller more accurate by saying that it is for debug purpose only and its interfaces are unstable. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* | Merge branch 'sched-core-for-linus' of ↵Linus Torvalds2017-07-032-5/+23
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this cycle were: - Add the SYSTEM_SCHEDULING bootup state to move various scheduler debug checks earlier into the bootup. This turns silent and sporadically deadly bugs into nice, deterministic splats. Fix some of the splats that triggered. (Thomas Gleixner) - A round of restructuring and refactoring of the load-balancing and topology code (Peter Zijlstra) - Another round of consolidating ~20 of incremental scheduler code history: this time in terms of wait-queue nomenclature. (I didn't get much feedback on these renaming patches, and we can still easily change any names I might have misplaced, so if anyone hates a new name, please holler and I'll fix it.) (Ingo Molnar) - sched/numa improvements, fixes and updates (Rik van Riel) - Another round of x86/tsc scheduler clock code improvements, in hope of making it more robust (Peter Zijlstra) - Improve NOHZ behavior (Frederic Weisbecker) - Deadline scheduler improvements and fixes (Luca Abeni, Daniel Bristot de Oliveira) - Simplify and optimize the topology setup code (Lauro Ramos Venancio) - Debloat and decouple scheduler code some more (Nicolas Pitre) - Simplify code by making better use of llist primitives (Byungchul Park) - ... plus other fixes and improvements" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits) sched/cputime: Refactor the cputime_adjust() code sched/debug: Expose the number of RT/DL tasks that can migrate sched/numa: Hide numa_wake_affine() from UP build sched/fair: Remove effective_load() sched/numa: Implement NUMA node level wake_affine() sched/fair: Simplify wake_affine() for the single socket case sched/numa: Override part of migrate_degrades_locality() when idle balancing sched/rt: Move RT related code from sched/core.c to sched/rt.c sched/deadline: Move DL related code from sched/core.c to sched/deadline.c sched/cpuset: Only offer CONFIG_CPUSETS if SMP is enabled sched/fair: Spare idle load balancing on nohz_full CPUs nohz: Move idle balancer registration to the idle path sched/loadavg: Generalize "_idle" naming to "_nohz" sched/core: Drop the unused try_get_task_struct() helper function sched/fair: WARN() and refuse to set buddy when !se->on_rq sched/debug: Fix SCHED_WARN_ON() to return a value on !CONFIG_SCHED_DEBUG as well sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming sched/wait: Move bit_wait_table[] and related functionality from sched/core.c to sched/wait_bit.c sched/wait: Split out the wait_bit*() APIs from <linux/wait.h> into <linux/wait_bit.h> sched/wait: Re-adjust macro line continuation backslashes in <linux/wait.h> ...
| * | sched/cpuset: Only offer CONFIG_CPUSETS if SMP is enabledNicolas Pitre2017-06-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make CONFIG_CPUSETS=y depend on SMP as this feature makes no sense on UP. This allows for configuring out cpuset_cpumask_can_shrink() and task_can_attach() entirely, which shrinks the kernel a bit. Signed-off-by: Nicolas Pitre <nico@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170614171926.8345-2-nicolas.pitre@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | sched/core: Enable might_sleep() and smp_processor_id() checks earlyThomas Gleixner2017-05-231-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | might_sleep() and smp_processor_id() checks are enabled after the boot process is done. That hides bugs in the SMP bringup and driver initialization code. Enable it right when the scheduler starts working, i.e. when init task and kthreadd have been created and right before the idle task enables preemption. Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20170516184736.272225698@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | init: Pin init task to the boot CPU, initiallyThomas Gleixner2017-05-231-5/+12
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some of the boot code in init_kernel_freeable() which runs before SMP bringup assumes (rightfully) that it runs on the boot CPU and therefore can use smp_processor_id() in preemptible context. That works so far because the smp_processor_id() check starts to be effective after smp bringup. That's just wrong. Starting with SMP bringup and the ability to move threads around, smp_processor_id() in preemptible context is broken. Aside of that it does not make sense to allow init to run on all CPUs before sched_smp_init() has been run. Pin the init to the boot CPU so the existing code can continue to use smp_processor_id() without triggering the checks when the enabling of those checks starts earlier. Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20170516184734.943149935@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | rcu: Move RCU non-debug Kconfig options to kernel/rcuPaul E. McKenney2017-06-081-238/+1
| | | | | | | | | | | | | | | | | | | | RCU's Kconfig options are scattered, and there are enough of them that it would be good for them to be more centralized. This commit therefore extracts RCU's Kconfig options from init/Kconfig into a new kernel/rcu/Kconfig file. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* | rcu: Eliminate NOCBs CPU-state Kconfig optionsPaul E. McKenney2017-06-081-53/+0
| | | | | | | | | | | | | | | | | | | | The CONFIG_RCU_NOCB_CPU_ALL, CONFIG_RCU_NOCB_CPU_NONE, and CONFIG_RCU_NOCB_CPU_ZERO Kconfig options are used only in testing and are redundant with the rcu_nocbs= boot parameter. This commit therefore removes these three Kconfig options and adjusts the rcutorture scripts to use the boot parameter instead. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* | rcu: Remove debugfs tracingPaul E. McKenney2017-06-081-8/+0
| | | | | | | | | | | | | | | | | | RCU's debugfs tracing used to be the only reasonable low-level debug information available, but ftrace and event tracing has since surpassed the RCU debugfs level of usefulness. This commit therefore removes RCU's debugfs tracing. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* | srcu: Remove Classic SRCUPaul E. McKenney2017-06-081-19/+2
| | | | | | | | | | | | | | | | Classic SRCU was only ever intended to be a fallback in case of issues with Tree/Tiny SRCU, and the latter two are doing quite well in testing. This commit therefore removes Classic SRCU. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* | rcu: Remove the RCU_KTHREAD_PRIO Kconfig optionPaul E. McKenney2017-06-081-31/+0
| | | | | | | | | | | | | | | | | | | | | | Anything that can be done with the RCU_KTHREAD_PRIO Kconfig option can also be done with the rcutree.kthread_prio kernel boot parameter. This commit therefore removes this Kconfig option. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Rik van Riel <riel@redhat.com>
* | srcu: Apply trivial callback lists to shrink Tiny SRCUPaul E. McKenney2017-06-081-1/+1
| | | | | | | | | | | | | | | | | | | | The rcu_segcblist structure provides quite a bit of functionality, and Tiny SRCU needs almost none of it. So this commit replaces Tiny SRCU's uses of rcu_segcblist with a simple singly linked list with tail pointer. This change significantly reduces Tiny SRCU's memory footprint, more than making up for the growth caused by the creation of rcu_segcblist.c Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* | srcu: Make SRCU be once again optionalPaul E. McKenney2017-06-081-1/+0
|/ | | | | | | | | | | | Commit d160a727c40e ("srcu: Make SRCU be built by default") in response to build errors, which were caused by code that included srcu.h despite !SRCU. However, srcutiny.o is almost 2K of code, which is not insignificant for those attempting to run the Linux kernel on IoT devices. This commit therefore makes SRCU be once again optional, and adjusts srcu.h to allow error-free inclusion in !SRCU kernel builds. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Nicolas Pitre <nico@linaro.org>
* Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds2017-05-101-2/+41
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The main changes are: - Debloat RCU headers - Parallelize SRCU callback handling (plus overlapping patches) - Improve the performance of Tree SRCU on a CPU-hotplug stress test - Documentation updates - Miscellaneous fixes" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits) rcu: Open-code the rcu_cblist_n_lazy_cbs() function rcu: Open-code the rcu_cblist_n_cbs() function rcu: Open-code the rcu_cblist_empty() function rcu: Separately compile large rcu_segcblist functions srcu: Debloat the <linux/rcu_segcblist.h> header srcu: Adjust default auto-expediting holdoff srcu: Specify auto-expedite holdoff time srcu: Expedite first synchronize_srcu() when idle srcu: Expedited grace periods with reduced memory contention srcu: Make rcutorture writer stalls print SRCU GP state srcu: Exact tracking of srcu_data structures containing callbacks srcu: Make SRCU be built by default srcu: Fix Kconfig botch when SRCU not selected rcu: Make non-preemptive schedule be Tasks RCU quiescent state srcu: Expedite srcu_schedule_cbs_snp() callback invocation srcu: Parallelize callback handling kvm: Move srcu_struct fields to end of struct kvm rcu: Fix typo in PER_RCU_NODE_PERIOD header comment rcu: Use true/false in assignment to bool rcu: Use bool value directly ...
| * rcu: Separately compile large rcu_segcblist functionsPaul E. McKenney2017-05-021-0/+3
| | | | | | | | | | | | | | | | | | | | | | This commit creates a new kernel/rcu/rcu_segcblist.c file that contains non-trivial segcblist functions. Trivial functions remain as static inline functions in kernel/rcu/rcu_segcblist.h Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de>
| * srcu: Make SRCU be built by defaultPaul E. McKenney2017-04-241-0/+1
| | | | | | | | | | | | | | | | SRCU is optional, and included only if there is a "select SRCU" in effect. However, we now have Tiny SRCU, so this commit defaults CONFIG_SRCU=y. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| * srcu: Fix Kconfig botch when SRCU not selectedPaul E. McKenney2017-04-241-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the CONFIG_SRCU option is not selected, for example, when building arch/tile allnoconfig, the following build errors appear: kernel/rcu/tree.o: In function `srcu_online_cpu': tree.c:(.text+0x4248): multiple definition of `srcu_online_cpu' kernel/rcu/srcutree.o:srcutree.c:(.text+0x2120): first defined here kernel/rcu/tree.o: In function `srcu_offline_cpu': tree.c:(.text+0x4250): multiple definition of `srcu_offline_cpu' kernel/rcu/srcutree.o:srcutree.c:(.text+0x2160): first defined here The corresponding .config file shows CONFIG_TREE_SRCU=y, but no sign of CONFIG_SRCU, which fatally confuses SRCU's #ifdefs, resulting in the above errors. The reason this occurs is the folowing line in init/Kconfig's definition for TREE_SRCU: default y if !TINY_RCU && !CLASSIC_SRCU If CONFIG_CLASSIC_SRCU=n, as it will be in for allnoconfig, and if CONFIG_SMP=y, then we will get CONFIG_TREE_SRCU=y but no CONFIG_SRCU, as seen in the .config file, and which will result in the above errors. This error did not show up during rcutorture testing because rcutorture forces CONFIG_SRCU=y, as it must to prevent build errors in rcutorture.c. This commit therefore conditions TREE_SRCU (and TINY_SRCU, while it is at it) with SRCU, like this: default y if SRCU && !TINY_RCU && !CLASSIC_SRCU Reported-by: kbuild test robot <fengguang.wu@intel.com> Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20170423162205.GP3956@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * Merge branch 'for-mingo' of ↵Ingo Molnar2017-04-231-2/+37
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU updates from Paul E. McKenney: - Documentation updates. - Miscellaneous fixes. - Parallelize SRCU callback handling (plus overlapping patches). Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | *-. Merge branches 'doc.2017.04.12a', 'fixes.2017.04.19a' and 'srcu.2017.04.21a' ↵Paul E. McKenney2017-04-211-2/+37
| | |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | into HEAD doc.2017.04.12a: Documentation updates fixes.2017.04.19a: Miscellaneous fixes srcu.2017.04.21a: Parallelize SRCU callback handling
| | | | * srcu: Introduce CLASSIC_SRCU Kconfig optionPaul E. McKenney2017-04-181-2/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The TREE_SRCU rewrite is large and a bit on the non-simple side, so this commit helps reduce risk by allowing the old v4.11 SRCU algorithm to be selected using a new CLASSIC_SRCU Kconfig option that depends on RCU_EXPERT. The default is to use the new TREE_SRCU and TINY_SRCU algorithms, in order to help get these the testing that they need. However, if your users do not require the update-side scalability that is to be provided by TREE_SRCU, select RCU_EXPERT and then CLASSIC_SRCU to revert back to the old classic SRCU algorithm. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| | | | * srcu: Create a tiny SRCUPaul E. McKenney2017-04-181-0/+12
| | | |/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | In response to automated complaints about modifications to SRCU increasing its size, this commit creates a tiny SRCU that is used in SMP=n && PREEMPT=n builds. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| | | * rcu: Make RCU_FANOUT_LEAF help text more explicit about skew_tickPaul E. McKenney2017-04-191-2/+8
| | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | If you set RCU_FANOUT_LEAF too high, you can get lock contention on the leaf rcu_node, and you should boot with the skew_tick kernel parameter set in order to avoid this lock contention. This commit therefore upgrades the RCU_FANOUT_LEAF help text to explicitly state this. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* | | Merge tag 'tty-4.12-rc1' of ↵Linus Torvalds2017-05-081-1/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial updates from Greg KH: "Here is the "big" TTY/Serial patch updates for 4.12-rc1 Not a lot of new things here, the normal number of serial driver updates and additions, tiny bugs fixed, and some core files split up to make future changes a bit easier for Nicolas's "tiny-tty" work. All of these have been in linux-next for a while" * tag 'tty-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (62 commits) serial: small Makefile reordering tty: split job control support into a file of its own tty: move baudrate handling code to a file of its own console: move console_init() out of tty_io.c serial: 8250_early: Add earlycon support for Palmchip UART tty: pl011: use "qdf2400_e44" as the earlycon name for QDF2400 E44 vt: make mouse selection of non-ASCII consistent vt: set mouse selection word-chars to gpm's default imx-serial: Reduce RX DMA startup latency when opening for reading serial: omap: suspend device on probe errors serial: omap: fix runtime-pm handling on unbind tty: serial: omap: add UPF_BOOT_AUTOCONF flag for DT init serial: samsung: Remove useless spinlock serial: samsung: Add missing checks for dma_map_single failure serial: samsung: Use right device for DMA-mapping calls serial: imx: setup DCEDTE early and ensure DCD and RI irqs to be off tty: fix comment typo s/repsonsible/responsible/ tty: amba-pl011: Fix spurious TX interrupts serial: xuartps: Enable clocks in the pm disable case also serial: core: Re-use struct uart_port {name} field ...
| * | | console: move console_init() out of tty_io.cNicolas Pitre2017-04-181-1/+1
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | All the console driver handling code lives in printk.c. Move console_init() there as well so console support can still be used when the TTY code is configured out. No logical changes from this patch. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | | initramfs: use vfs_stat/lstat directlyArnd Bergmann2017-05-082-24/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sys_newlstat is a system call implementation that is meant for user space, and that copies kernel-internal data structure to the user format, which is not needed for in-kernel users. Further, as we rearrange the system call implementation so we can extend it with 64-bit time_t, the prototype for sys_newlstat changes. This changes the initramfs code to use vfs_lstat directly, to get it out of the way of the time_t changes, and make it slightly more efficient in the process. Along the same lines we also replace sys_stat and sys_stat64 with vfs_stat. Link: http://lkml.kernel.org/r/20170314214932.4052842-1-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | initramfs: provide a way to ignore image provided by bootloaderDaniel Thompson2017-05-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many "embedded" architectures provide CMDLINE_FORCE to allow the kernel to override the command line provided by an inflexible bootloader. However there is currrently no way for the kernel to override the initramfs image provided by the bootloader meaning there are still ways for bootloaders to make things difficult for us. Fix this by introducing INITRAMFS_FORCE which can prevent the kernel from loading the bootloader supplied image. We use CMDLINE_FORCE (and its friend CMDLINE_EXTEND) to imply that the system has an inflexible bootloader. This allow us to avoid presenting this config option to users of systems where inflexible bootloaders aren't usually a problem. Link: http://lkml.kernel.org/r/20170217121940.30126-1-daniel.thompson@linaro.org Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | initramfs: avoid "label at end of compound statement" errorLinus Torvalds2017-05-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 17a9be317475 ("initramfs: Always do fput() and load modules after rootfs populate") introduced an error for the CONFIG_BLK_DEV_RAM=y case, because even though the code looks fine, the compiler really wants a statement after a label, or you'll get complaints: init/initramfs.c: In function 'populate_rootfs': init/initramfs.c:644:2: error: label at end of compound statement That commit moved the subsequent statements to outside the compound statement, leaving the label without any associated statements. Reported-by: Jörg Otte <jrg.otte@gmail.com> Fixes: 17a9be317475 ("initramfs: Always do fput() and load modules after rootfs populate") Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: stable@vger.kernel.org # if 17a9be317475 gets backported Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge tag 'initramfs-fix-4.12-rc1' of git://github.com/stffrdhrn/linuxLinus Torvalds2017-05-051-6/+9
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull initramfs fix from Stafford Horne: "This is a fix for an issue that has caused 4.11 to not boot on OpenRISC. I should have caught this during the 4.11 cycle but I had been busy on testing some other series of patches. I would have considered pushing it though a different path but Al Viro suggested submitting directly to you. Also, its just one as I havent really got anything else ready on my queue for 4.12. Summary: - Ensure fput() flush is done even for builtin initramfs" * tag 'initramfs-fix-4.12-rc1' of git://github.com/stffrdhrn/linux: initramfs: Always do fput() and load modules after rootfs populate
| * | | initramfs: Always do fput() and load modules after rootfs populateStafford Horne2017-05-051-6/+9
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In OpenRISC we do not have a bootloader passed initrd, but the built in initramfs does contain the /init and other binaries, including modules. The previous commit 08865514805d2 ("initramfs: finish fput() before accessing any binary from initramfs") made a change to only call fput() if the bootloader initrd was available, this caused intermittent crashes for OpenRISC. This patch changes the fput() to happen unconditionally if any rootfs is loaded. Also, I added some comments to make it a bit more clear why we call unpack_to_rootfs() multiple times. Fixes: 08865514805d2 ("initramfs: finish fput() before accessing any binary from initramfs") Cc: stable@vger.kernel.org Cc: Lokesh Vutla <lokeshvutla@ti.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Stafford Horne <shorne@gmail.com>
* | | Merge tag 'trace-v4.12' of ↵Linus Torvalds2017-05-031-3/+7
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "New features for this release: - Pretty much a full rewrite of the processing of function plugins. i.e. echo do_IRQ:stacktrace > set_ftrace_filter - The rewrite was needed to add plugins to be unique to tracing instances. i.e. mkdir instance/foo; cd instances/foo; echo do_IRQ:stacktrace > set_ftrace_filter The old way was written very hacky. This removes a lot of those hacks. - New "function-fork" tracing option. When set, pids in the set_ftrace_pid will have their children added when the processes with their pids listed in the set_ftrace_pid file forks. - Exposure of "maxactive" for kretprobe in kprobe_events - Allow for builtin init functions to be traced by the function tracer (via the kernel command line). Module init function tracing will come in the next release. - Added more selftests, and have selftests also test in an instance" * tag 'trace-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (60 commits) ring-buffer: Return reader page back into existing ring buffer selftests: ftrace: Allow some event trigger tests to run in an instance selftests: ftrace: Have some basic tests run in a tracing instance too selftests: ftrace: Have event tests also run in an tracing instance selftests: ftrace: Make func_event_triggers and func_traceonoff_triggers tests do instances selftests: ftrace: Allow some tests to be run in a tracing instance tracing/ftrace: Allow for instances to trigger their own stacktrace probes tracing/ftrace: Allow for the traceonoff probe be unique to instances tracing/ftrace: Enable snapshot function trigger to work with instances tracing/ftrace: Allow instances to have their own function probes tracing/ftrace: Add a better way to pass data via the probe functions ftrace: Dynamically create the probe ftrace_ops for the trace_array tracing: Pass the trace_array into ftrace_probe_ops functions tracing: Have the trace_array hold the list of registered func probes ftrace: If the hash for a probe fails to update then free what was initialized ftrace: Have the function probes call their own function ftrace: Have each function probe use its own ftrace_ops ftrace: Have unregister_ftrace_function_probe_func() return a value ftrace: Add helper function ftrace_hash_move_and_update_ops() ftrace: Remove data field from ftrace_func_probe structure ...
| * | | ftrace: Have init/main.c call ftrace directly to free init memorySteven Rostedt (VMware)2017-04-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Relying on free_reserved_area() to call ftrace to free init memory proved to not be sufficient. The issue is that on x86, when debug_pagealloc is enabled, the init memory is not freed, but simply set as not present. Since ftrace was uninformed of this, starting function tracing still tries to update pages that are not present according to the page tables, causing ftrace to bug, as well as killing the kernel itself. Instead of relying on free_reserved_area(), have init/main.c call ftrace directly just before it frees the init memory. Then it needs to use __init_begin and __init_end to know where the init memory location is. Looking at all archs (and testing what I can), it appears that this should work for each of them. Reported-by: kernel test robot <xiaolong.ye@intel.com> Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | ftrace: Move ftrace_init() to right after memory initializationSteven Rostedt (VMware)2017-03-241-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Initialize the ftrace records immediately after memory initialization, as that is all that is required for the records to be created. This will allow for future work to get function tracing started earlier in the boot process. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: Split tracing initialization into two for early initializationSteven Rostedt (VMware)2017-03-241-1/+4
| | |/ | |/| | | | | | | | | | | | | | | | | | | Create an early_trace_init() function that will initialize the buffers and allow for ealier use of trace_printk(). This will also allow for future work to have function tracing start earlier at boot up. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | | Merge branch 'for-linus' of ↵Linus Torvalds2017-05-021-5/+5
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: tty: fix comment for __tty_alloc_driver() init/main: properly align the multi-line comment init/main: Fix double "the" in comment Fix dead URLs to ftp.kernel.org drivers: Clean up duplicated email address treewide: Fix typo in xml/driver-api/basics.xml tools/testing/selftests/powerpc: remove redundant CFLAGS in Makefile: "-Wall -O2 -Wall" -> "-O2 -Wall" selftests/timers: Spelling s/privledges/privileges/ HID: picoLCD: Spelling s/REPORT_WRTIE_MEMORY/REPORT_WRITE_MEMORY/ net: phy: dp83848: Fix Typo UBI: Fix typos Documentation: ftrace.txt: Correct nice value of 120 priority net: fec: Fix typo in error msg and comment treewide: Fix typos in printk
| * | init/main: properly align the multi-line commentViresh Kumar2017-04-241-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | Add a tab before it to follow standard practices. Also add the missing full stop '.'. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
| * | init/main: Fix double "the" in commentViresh Kumar2017-04-241-1/+1
| |/ | | | | | | | | | | | | s/the\ the/the Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* / mm: move mm_percpu_wq initialization earlierMichal Hocko2017-03-311-0/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Yang Li has reported that drain_all_pages triggers a WARN_ON which means that this function is called earlier than the mm_percpu_wq is initialized on arm64 with CMA configured: WARNING: CPU: 2 PID: 1 at mm/page_alloc.c:2423 drain_all_pages+0x244/0x25c Modules linked in: CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.11.0-rc1-next-20170310-00027-g64dfbc5 #127 Hardware name: Freescale Layerscape 2088A RDB Board (DT) task: ffffffc07c4a6d00 task.stack: ffffffc07c4a8000 PC is at drain_all_pages+0x244/0x25c LR is at start_isolate_page_range+0x14c/0x1f0 [...] drain_all_pages+0x244/0x25c start_isolate_page_range+0x14c/0x1f0 alloc_contig_range+0xec/0x354 cma_alloc+0x100/0x1fc dma_alloc_from_contiguous+0x3c/0x44 atomic_pool_init+0x7c/0x208 arm64_dma_init+0x44/0x4c do_one_initcall+0x38/0x128 kernel_init_freeable+0x1a0/0x240 kernel_init+0x10/0xfc ret_from_fork+0x10/0x20 Fix this by moving the whole setup_vmstat which is an initcall right now to init_mm_internals which will be called right after the WQ subsystem is initialized. Link: http://lkml.kernel.org/r/20170315164021.28532-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Yang Li <pku.leo@gmail.com> Tested-by: Yang Li <pku.leo@gmail.com> Tested-by: Xiaolong Ye <xiaolong.ye@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'random_for_linus' of ↵Linus Torvalds2017-03-111-1/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random Pull random updates from Ted Ts'o: "Change get_random_{int,log} to use the CRNG used by /dev/urandom and getrandom(2). It's faster and arguably more secure than cut-down MD5 that we had been using. Also do some code cleanup" * tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: random: move random_min_urandom_seed into CONFIG_SYSCTL ifdef block random: convert get_random_int/long into get_random_u32/u64 random: use chacha20 for get_random_int/long random: fix comment for unused random_min_urandom_seed random: remove variable limit random: remove stale urandom_init_wait random: remove stale maybe_reseed_primary_crng
| * random: use chacha20 for get_random_int/longJason A. Donenfeld2017-01-271-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that our crng uses chacha20, we can rely on its speedy characteristics for replacing MD5, while simultaneously achieving a higher security guarantee. Before the idea was to use these functions if you wanted random integers that aren't stupidly insecure but aren't necessarily secure either, a vague gray zone, that hopefully was "good enough" for its users. With chacha20, we can strengthen this claim, since either we're using an rdrand-like instruction, or we're using the same crng as /dev/urandom. And it's faster than what was before. We could have chosen to replace this with a SipHash-derived function, which might be slightly faster, but at the cost of having yet another RNG construction in the kernel. By moving to chacha20, we have a single RNG to analyze and verify, and we also already get good performance improvements on all platforms. Implementation-wise, rather than use a generic buffer for both get_random_int/long and memcpy based on the size needs, we use a specific buffer for 32-bit reads and for 64-bit reads. This way, we're guaranteed to always have aligned accesses on all platforms. While slightly more verbose in C, the assembly this generates is a lot simpler than otherwise. Finally, on 32-bit platforms where longs and ints are the same size, we simply alias get_random_int to get_random_long. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Suggested-by: Theodore Ts'o <tytso@mit.edu> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Cc: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* | sched/headers: Prepare to move _init() prototypes from <linux/sched.h> to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/init.h> But first introduce a trivial header and update usage sites. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers, vfs/execve: Prepare to move the do_execve*() prototypes from ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched.h> to <linux/binfmts.h> But first update the usage sites with the new header dependency. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare to move 'init_task' and 'init_thread_union' from ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched.h> to <linux/sched/task.h> Update all usage sites first. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/task_stack.h> We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task_stack.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/task.h> We are going to split <linux/sched/task.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/nmi.h> We are going to move softlockup APIs out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. <linux/nmi.h> already includes <linux/sched.h>. Include the <linux/nmi.h> header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge branch 'idr-4.11' of git://git.infradead.org/users/willy/linux-daxLinus Torvalds2017-02-281-2/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull IDR rewrite from Matthew Wilcox: "The most significant part of the following is the patch to rewrite the IDR & IDA to be clients of the radix tree. But there's much more, including an enhancement of the IDA to be significantly more space efficient, an IDR & IDA test suite, some improvements to the IDR API (and driver changes to take advantage of those improvements), several improvements to the radix tree test suite and RCU annotations. The IDR & IDA rewrite had a good spin in linux-next and Andrew's tree for most of the last cycle. Coupled with the IDR test suite, I feel pretty confident that any remaining bugs are quite hard to hit. 0-day did a great job of watching my git tree and pointing out problems; as it hit them, I added new test-cases to be sure not to be caught the same way twice" Willy goes on to expand a bit on the IDR rewrite rationale: "The radix tree and the IDR use very similar data structures. Merging the two codebases lets us share the memory allocation pools, and results in a net deletion of 500 lines of code. It also opens up the possibility of exposing more of the features of the radix tree to users of the IDR (and I have some interesting patches along those lines waiting for 4.12) It also shrinks the size of the 'struct idr' from 40 bytes to 24 which will shrink a fair few data structures that embed an IDR" * 'idr-4.11' of git://git.infradead.org/users/willy/linux-dax: (32 commits) radix tree test suite: Add config option for map shift idr: Add missing __rcu annotations radix-tree: Fix __rcu annotations radix-tree: Add rcu_dereference and rcu_assign_pointer calls radix tree test suite: Run iteration tests for longer radix tree test suite: Fix split/join memory leaks radix tree test suite: Fix leaks in regression2.c radix tree test suite: Fix leaky tests radix tree test suite: Enable address sanitizer radix_tree_iter_resume: Fix out of bounds error radix-tree: Store a pointer to the root in each node radix-tree: Chain preallocated nodes through ->parent radix tree test suite: Dial down verbosity with -v radix tree test suite: Introduce kmalloc_verbose idr: Return the deleted entry from idr_remove radix tree test suite: Build separate binaries for some tests ida: Use exceptional entries for small IDAs ida: Move ida_bitmap to a percpu variable Reimplement IDR and IDA using the radix tree radix-tree: Add radix_tree_iter_delete ...
| * | Reimplement IDR and IDA using the radix treeMatthew Wilcox2017-02-131-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The IDR is very similar to the radix tree. It has some functionality that the radix tree did not have (alloc next free, cyclic allocation, a callback-based for_each, destroy tree), which is readily implementable on top of the radix tree. A few small changes were needed in order to use a tag to represent nodes with free space below them. More extensive changes were needed to support storing NULL as a valid entry in an IDR. Plain radix trees still interpret NULL as a not-present entry. The IDA is reimplemented as a client of the newly enhanced radix tree. As in the current implementation, it uses a bitmap at the last level of the tree. Signed-off-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>