user/sven/linux.git/kernel/locking/lockdep.c, branch v6.1.13

locking/lockdep: Print more debug information - report name and key when look_up_lock_class() got confused

2022-09-21T07:58:21Z

Printing this information will be helpful: ------------[ cut here ]------------ Looking for class "l2tp_sock" with key l2tp_socket_class, but found a different class "slock-AF_INET6" with the same key WARNING: CPU: 1 PID: 14195 at kernel/locking/lockdep.c:940 look_up_lock_class+0xcc/0x140 Modules linked in: CPU: 1 PID: 14195 Comm: a.out Not tainted 6.0.0-rc6-dirty #863 Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 RIP: 0010:look_up_lock_class+0xcc/0x140 Signed-off-by: Tetsuo Handa Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/bd99391e-f787-efe9-5ec6-3c6dc4c587b0@I-love.SAKURA.ne.jp

Merge tag 'rcu.2022.07.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

2022-08-03T02:12:45Z

Pull RCU updates from Paul McKenney: - Documentation updates - Miscellaneous fixes - Callback-offload updates, perhaps most notably a new RCU_NOCB_CPU_DEFAULT_ALL Kconfig option that causes all CPUs to be offloaded at boot time, regardless of kernel boot parameters. This is useful to battery-powered systems such as ChromeOS and Android. In addition, a new RCU_NOCB_CPU_CB_BOOST kernel boot parameter prevents offloaded callbacks from interfering with real-time workloads and with energy-efficiency mechanisms - Polled grace-period updates, perhaps most notably making these APIs account for both normal and expedited grace periods - Tasks RCU updates, perhaps most notably reducing the CPU overhead of RCU tasks trace grace periods by more than a factor of two on a system with 15,000 tasks. The reduction is expected to increase with the number of tasks, so it seems reasonable to hypothesize that a system with 150,000 tasks might see a 20-fold reduction in CPU overhead - Torture-test updates - Updates that merge RCU's dyntick-idle tracking into context tracking, thus reducing the overhead of transitioning to kernel mode from either idle or nohz_full userspace execution for kernels that track context independently of RCU. This is expected to be helpful primarily for kernels built with CONFIG_NO_HZ_FULL=y * tag 'rcu.2022.07.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (98 commits) rcu: Add irqs-disabled indicator to expedited RCU CPU stall warnings rcu: Diagnose extended sync_rcu_do_polled_gp() loops rcu: Put panic_on_rcu_stall() after expedited RCU CPU stall warnings rcutorture: Test polled expedited grace-period primitives rcu: Add polled expedited grace-period primitives rcutorture: Verify that polled GP API sees synchronous grace periods rcu: Make Tiny RCU grace periods visible to polled APIs rcu: Make polled grace-period API account for expedited grace periods rcu: Switch polled grace-period APIs to ->gp_seq_polled rcu/nocb: Avoid polling when my_rdp->nocb_head_rdp list is empty rcu/nocb: Add option to opt rcuo kthreads out of RT priority rcu: Add nocb_cb_kthread check to rcu_is_callbacks_kthread() rcu/nocb: Add an option to offload all CPUs on boot rcu/nocb: Fix NOCB kthreads spawn failure with rcu_nocb_rdp_deoffload() direct call rcu/nocb: Invert rcu_state.barrier_mutex VS hotplug lock locking order rcu/nocb: Add/del rdp to iterate from rcuog itself rcu/tree: Add comment to describe GP-done condition in fqs loop rcu: Initialize first_gp_fqs at declaration in rcu_gp_fqs() rcu/kvfree: Remove useless monitor_todo flag rcu: Cleanup RCU urgency state for offline CPU ...

context_tracking: Take idle eqs entrypoints over RCU

2022-07-05T20:32:16Z

The RCU dynticks counter is going to be merged into the context tracking subsystem. Start with moving the idle extended quiescent states entrypoints to context tracking. For now those are dumb redirections to existing RCU calls. [ paulmck: Apply kernel test robot feedback. ] Signed-off-by: Frederic Weisbecker Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Neeraj Upadhyay Cc: Uladzislau Rezki Cc: Joel Fernandes Cc: Boqun Feng Cc: Nicolas Saenz Julienne Cc: Marcelo Tosatti Cc: Xiongfeng Wang Cc: Yu Liao Cc: Phil Auld Cc: Paul Gortmaker Cc: Alex Belits Signed-off-by: Paul E. McKenney Reviewed-by: Nicolas Saenz Julienne Tested-by: Nicolas Saenz Julienne

locking/lockdep: Fix lockdep_init_map_*() confusion

2022-06-24T07:48:56Z

Commit dfd5e3f5fe27 ("locking/lockdep: Mark local_lock_t") added yet another lockdep_init_map_*() variant, but forgot to update all the existing users of the most complicated version. This could lead to a loss of lock_type and hence an incorrect report. Given the relative rarity of both local_lock and these annotations, this is unlikely to happen in practise, still, best fix things. Fixes: dfd5e3f5fe27 ("locking/lockdep: Mark local_lock_t") Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/YqyEDtoan20K0CVD@worktop.programming.kicks-ass.net

locking/lockdep: Use sched_clock() for random numbers

2022-06-13T08:29:57Z

Since the rewrote of prandom_u32(), in the commit mentioned below, the function uses sleeping locks which extracing random numbers and filling the batch. This breaks lockdep on PREEMPT_RT because lock_pin_lock() disables interrupts while calling __lock_pin_lock(). This can't be moved earlier because the main user of the function (rq_pin_lock()) invokes that function after disabling interrupts in order to acquire the lock. The cookie does not require random numbers as its goal is to provide a random value in order to notice unexpected "unlock + lock" sites. Use sched_clock() to provide random numbers. Fixes: a0103f4d86f88 ("random32: use real rng for non-deterministic randomness") Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/YoNn3pTkm5+QzE5k@linutronix.de

Merge tag 'sysctl-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

2022-05-26T23:57:20Z

Pull sysctl updates from Luis Chamberlain: "For two kernel releases now kernel/sysctl.c has been being cleaned up slowly, since the tables were grossly long, sprinkled with tons of #ifdefs and all this caused merge conflicts with one susbystem or another. This tree was put together to help try to avoid conflicts with these cleanups going on different trees at time. So nothing exciting on this pull request, just cleanups. Thanks a lot to the Uniontech and Huawei folks for doing some of this nasty work" * tag 'sysctl-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (28 commits) sched: Fix build warning without CONFIG_SYSCTL reboot: Fix build warning without CONFIG_SYSCTL kernel/kexec_core: move kexec_core sysctls into its own file sysctl: minor cleanup in new_dir() ftrace: fix building with SYSCTL=y but DYNAMIC_FTRACE=n fs/proc: Introduce list_for_each_table_entry for proc sysctl mm: fix unused variable kernel warning when SYSCTL=n latencytop: move sysctl to its own file ftrace: fix building with SYSCTL=n but DYNAMIC_FTRACE=y ftrace: Fix build warning ftrace: move sysctl_ftrace_enabled to ftrace.c kernel/do_mount_initrd: move real_root_dev sysctls to its own file kernel/delayacct: move delayacct sysctls to its own file kernel/acct: move acct sysctls to its own file kernel/panic: move panic sysctls to its own file kernel/lockdep: move lockdep sysctls to its own file mm: move page-writeback sysctls to their own file mm: move oom_kill sysctls to their own file kernel/reboot: move reboot sysctls to its own file sched: Move energy_aware sysctls to topology.c ...

kernel/lockdep: move lockdep sysctls to its own file

2022-04-06T20:43:44Z

kernel/sysctl.c is a kitchen sink where everyone leaves their dirty dishes, this makes it very difficult to maintain. To help with this maintenance let's start by moving sysctls to places where they actually belong. The proc sysctl maintainers do not want to know what sysctl knobs you wish to add for your own piece of code, we just care about the core logic. All filesystem syctls now get reviewed by fs folks. This commit follows the commit of fs, move the prove_locking and lock_stat sysctls to its own file, kernel/lockdep.c. Signed-off-by: tangmeng Signed-off-by: Luis Chamberlain

locking: Add lock contention tracepoints

2022-04-05T08:24:35Z

This adds two new lock contention tracepoints like below: * lock:contention_begin * lock:contention_end The lock:contention_begin takes a flags argument to classify locks. I found it useful to identify what kind of locks it's tracing like if it's spinning or sleeping, reader-writer lock, real-time, and per-cpu. Move tracepoint definitions into mutex.c so that we can use them without lockdep. Signed-off-by: Namhyung Kim Signed-off-by: Peter Zijlstra (Intel) Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Link: https://lkml.kernel.org/r/20220322185709.141236-2-namhyung@kernel.org

lockdep: Fix -Wunused-parameter for _THIS_IP_

2022-04-05T08:24:34Z

While looking into a bug related to the compiler's handling of addresses of labels, I noticed some uses of _THIS_IP_ seemed unused in lockdep. Drive by cleanup. -Wunused-parameter: kernel/locking/lockdep.c:1383:22: warning: unused parameter 'ip' kernel/locking/lockdep.c:4246:48: warning: unused parameter 'ip' kernel/locking/lockdep.c:4844:19: warning: unused parameter 'ip' Signed-off-by: Nick Desaulniers Signed-off-by: Peter Zijlstra (Intel) Acked-by: Waiman Long Link: https://lore.kernel.org/r/20220314221909.2027027-1-ndesaulniers@google.com

Merge tag 'locking-core-2022-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2022-03-22T20:44:21Z

Pull locking updates from Ingo Molnar: "Changes in this cycle were: Bitops & cpumask: - Always inline various generic helpers, to improve code generation, but also for instrumentation, found by noinstr validation. - Add a x86-specific cpumask_clear_cpu() helper to improve code generation Atomics: - Fix atomic64_{read_acquire,set_release} fallbacks Lockdep: - Fix /proc/lockdep output loop iteration for classes - Fix /proc/lockdep potential access to invalid memory - Add Mark Rutland as reviewer for atomic primitives - Minor cleanups Jump labels: - Clean up the code a bit Misc: - Add __sched annotations to percpu rwsem primitives - Enable RT_MUTEXES on PREEMPT_RT by default - Stray v8086_mode() inlining fix, result of noinstr objtool validation" * tag 'locking-core-2022-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: jump_label: Refactor #ifdef of struct static_key jump_label: Avoid unneeded casts in STATIC_KEY_INIT_{TRUE,FALSE} locking/lockdep: Iterate lock_classes directly when reading lockdep files x86/ptrace: Always inline v8086_mode() for instrumentation cpumask: Add a x86-specific cpumask_clear_cpu() helper locking: Enable RT_MUTEXES by default on PREEMPT_RT. locking/local_lock: Make the empty local_lock_*() function a macro. atomics: Fix atomic64_{read_acquire,set_release} fallbacks locking: Add missing __sched attributes cpumask: Always inline helpers which use bit manipulation functions asm-generic/bitops: Always inline all bit manipulation helpers locking/lockdep: Avoid potential access of invalid memory in lock_class lockdep: Use memset_startat() helper in reinit_class() MAINTAINERS: add myself as reviewer for atomics