From 9cc63f8bcd560c760d0b12e15bba8f81c86237cf Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 14 Aug 2026 15:43:51 -0700 Subject: Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEAD Changes: Make expedited grace periods expedite normal RCU callbacks Miscellaneous fixes: * Improve diagnostic output with character task states. * Mark accesses to inform KCSAN of concurrency design. * Move from kmalloc() to kmalloc_obj(). * Documentation updates. * Improve handling of RCU deferred quiescent states. * Clean up unused function arguments and structure fields. * Reduce show_rcu_gp_kthreads() stack space. Tasks RCU updates: * Clean up after SRCU re-implementation of Tasks Trace RCU. * Mark accesses to inform KCSAN of concurrency design. * Add ->lazy_timer status to diagnostic output. * Remove an unnecessary memory barrier. * Fix a data race, courtesy of KCSAN. * Documentation updates. * Convert cond_resched_tasks_rcu_qs() from macro to static inline function. SRCU updates: * Add Rust helpers for SRCU. * Avoid losing queued work at cleanup_srcu_struct() time. Torture-test updates: * Preparation work for immediate RCU priority deboosting. * Test RCU readers from real interrupt handlers (as opposed to softirq). * Simplify code through use of cpumask_next_wrap(). * Improve diagnostic output with character task states. * Add rcutorture.nwriters parameter to allow lightweight stall testing, and rcutorture.stall_only to make doing so easier. * Test an RCU Tasks Trace grace period implying an RCU grace period. * Make RCU Tasks Trace torturing track reader batches. * Fix a data race, courtesy of KCSAN. * Plug a shuffle_tmp_mask memory leak on kthread spawn failure. --- include/asm-generic/bitsperlong.h | 47 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 include/asm-generic/bitsperlong.h (limited to 'include/asm-generic/bitsperlong.h') diff --git a/include/asm-generic/bitsperlong.h b/include/asm-generic/bitsperlong.h new file mode 100644 index 000000000..90e8aeebf --- /dev/null +++ b/include/asm-generic/bitsperlong.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_GENERIC_BITS_PER_LONG +#define __ASM_GENERIC_BITS_PER_LONG + +#include + + +#ifdef CONFIG_64BIT +#define BITS_PER_LONG 64 +#else +#define BITS_PER_LONG 32 +#endif /* CONFIG_64BIT */ + +/* + * FIXME: The check currently breaks x86-64 build, so it's + * temporarily disabled. Please fix x86-64 and reenable + */ +#if 0 && BITS_PER_LONG != __BITS_PER_LONG +#error Inconsistent word size. Check asm/bitsperlong.h +#endif + +#if __CHAR_BIT__ * __SIZEOF_LONG__ != __BITS_PER_LONG +#error Inconsistent word size. Check asm/bitsperlong.h +#endif + +#ifndef __ASSEMBLER__ +_Static_assert(sizeof(long) * 8 == __BITS_PER_LONG, + "Inconsistent word size. Check asm/bitsperlong.h"); +#endif + +#ifndef BITS_PER_LONG_LONG +#define BITS_PER_LONG_LONG 64 +#endif + +/* + * small_const_nbits(n) is true precisely when it is known at compile-time + * that BITMAP_SIZE(n) is 1, i.e. 1 <= n <= BITS_PER_LONG. This allows + * various bit/bitmap APIs to provide a fast inline implementation. Bitmaps + * of size 0 are very rare, and a compile-time-known-size 0 is most likely + * a sign of error. They will be handled correctly by the bit/bitmap APIs, + * but using the out-of-line functions, so that the inline implementations + * can unconditionally dereference the pointer(s). + */ +#define small_const_nbits(nbits) \ + (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG && (nbits) > 0) + +#endif /* __ASM_GENERIC_BITS_PER_LONG */ -- cgit v1.3.1