linux/kernel/rcu/update.c, branch v5.8

rcu/tree: Mark the idle relevant functions noinstr

2020-05-19T13:51:20Z

These functions are invoked from context tracking and other places in the low level entry code. Move them into the .noinstr.text section to exclude them from instrumentation. Mark the places which are safe to invoke traceable functions with instrumentation_begin/end() so objtool won't complain. Signed-off-by: Thomas Gleixner Reviewed-by: Alexandre Chartre Acked-by: Peter Zijlstra Acked-by: Paul E. McKenney Link: https://lkml.kernel.org/r/20200505134100.575356107@linutronix.de

Merge branches 'fixes.2020.04.27a', 'kfree_rcu.2020.04.27a', 'rcu-tasks.2020.04.27a', 'stall.2020.04.27a' and 'torture.2020.05.07a' into HEAD

2020-05-07T17:18:32Z

fixes.2020.04.27a: Miscellaneous fixes. kfree_rcu.2020.04.27a: Changes related to kfree_rcu(). rcu-tasks.2020.04.27a: Addition of new RCU-tasks flavors. stall.2020.04.27a: RCU CPU stall-warning updates. torture.2020.05.07a: Torture-test updates.

rcu-tasks: Allow rcu_read_unlock_trace() under scheduler locks

2020-04-27T18:03:52Z

The rcu_read_unlock_trace() can invoke rcu_read_unlock_trace_special(), which in turn can call wake_up(). Therefore, if any scheduler lock is held across a call to rcu_read_unlock_trace(), self-deadlock can occur. This commit therefore uses the irq_work facility to defer the wake_up() to a clean environment where no scheduler locks will be held. Reported-by: Steven Rostedt [ paulmck: Update #includes for m68k per kbuild test robot. ] Signed-off-by: Paul E. McKenney

rcu-tasks: Move #ifdef into tasks.h

2020-04-27T18:03:51Z

This commit pushes the #ifdef CONFIG_TASKS_RCU_GENERIC from kernel/rcu/update.c to kernel/rcu/tasks.h in order to improve readability as more APIs are added. Signed-off-by: Paul E. McKenney

rcu-tasks: Refactor RCU-tasks to allow variants to be added

2020-04-27T18:03:51Z

This commit splits out generic processing from RCU-tasks-specific processing in order to allow additional flavors to be added. It also adds a def_bool TASKS_RCU_GENERIC to enable the common RCU-tasks infrastructure code. This is primarily, but not entirely, a code-movement commit. Signed-off-by: Paul E. McKenney

rcu-tasks: Move Tasks RCU to its own file

2020-04-27T18:03:50Z

This code-movement-only commit is in preparation for adding an additional flavor of Tasks RCU, which relies on workqueues to detect grace periods. Signed-off-by: Paul E. McKenney

rcu: Add KCSAN stubs to update.c

2020-04-27T18:03:50Z

This commit adds stubs for KCSAN's data_race(), ASSERT_EXCLUSIVE_WRITER(), and ASSERT_EXCLUSIVE_ACCESS() macros to allow code using these macros to move ahead. Signed-off-by: Paul E. McKenney

rcu: Replace assigned pointer ret value by corresponding boolean value

2020-04-27T18:01:16Z

Coccinelle reports warnings at rcu_read_lock_held_common() WARNING: Assignment of 0/1 to bool variable To fix this, the assigned pointer ret values are replaced by corresponding boolean value. Given that ret is a pointer of bool type Signed-off-by: Jules Irenge Signed-off-by: Paul E. McKenney

rcu: Get rid of some doc warnings in update.c

2020-04-27T18:01:16Z

This commit escapes *ret, because otherwise the documentation system thinks that this is an incomplete emphasis block: ./kernel/rcu/update.c:65: WARNING: Inline emphasis start-string without end-string. ./kernel/rcu/update.c:65: WARNING: Inline emphasis start-string without end-string. ./kernel/rcu/update.c:70: WARNING: Inline emphasis start-string without end-string. ./kernel/rcu/update.c:82: WARNING: Inline emphasis start-string without end-string. Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Paul E. McKenney

Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-03-30T23:17:15Z

Pull locking updates from Ingo Molnar: "The main changes in this cycle were: - Continued user-access cleanups in the futex code. - percpu-rwsem rewrite that uses its own waitqueue and atomic_t instead of an embedded rwsem. This addresses a couple of weaknesses, but the primary motivation was complications on the -rt kernel. - Introduce raw lock nesting detection on lockdep (CONFIG_PROVE_RAW_LOCK_NESTING=y), document the raw_lock vs. normal lock differences. This too originates from -rt. - Reuse lockdep zapped chain_hlocks entries, to conserve RAM footprint on distro-ish kernels running into the "BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!" depletion of the lockdep chain-entries pool. - Misc cleanups, smaller fixes and enhancements - see the changelog for details" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (55 commits) fs/buffer: Make BH_Uptodate_Lock bit_spin_lock a regular spinlock_t thermal/x86_pkg_temp: Make pkg_temp_lock a raw_spinlock_t Documentation/locking/locktypes: Minor copy editor fixes Documentation/locking/locktypes: Further clarifications and wordsmithing m68knommu: Remove mm.h include from uaccess_no.h x86: get rid of user_atomic_cmpxchg_inatomic() generic arch_futex_atomic_op_inuser() doesn't need access_ok() x86: don't reload after cmpxchg in unsafe_atomic_op2() loop x86: convert arch_futex_atomic_op_inuser() to user_access_begin/user_access_end() objtool: whitelist __sanitizer_cov_trace_switch() [parisc, s390, sparc64] no need for access_ok() in futex handling sh: no need of access_ok() in arch_futex_atomic_op_inuser() futex: arch_futex_atomic_op_inuser() calling conventions change completion: Use lockdep_assert_RT_in_threaded_ctx() in complete_all() lockdep: Add posixtimer context tracing bits lockdep: Annotate irq_work lockdep: Add hrtimer context tracing bits lockdep: Introduce wait-type checks completion: Use simple wait queues sched/swait: Prepare usage in completions ...