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. --- arch/mips/lib/mips-atomic.c | 113 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 113 insertions(+) create mode 100644 arch/mips/lib/mips-atomic.c (limited to 'arch/mips/lib/mips-atomic.c') diff --git a/arch/mips/lib/mips-atomic.c b/arch/mips/lib/mips-atomic.c new file mode 100644 index 000000000..a9b72eacf --- /dev/null +++ b/arch/mips/lib/mips-atomic.c @@ -0,0 +1,113 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 1994, 95, 96, 97, 98, 99, 2003 by Ralf Baechle + * Copyright (C) 1996 by Paul M. Antoine + * Copyright (C) 1999 Silicon Graphics + * Copyright (C) 2000 MIPS Technologies, Inc. + */ +#include +#include +#include +#include +#include +#include + +#if !defined(CONFIG_CPU_HAS_DIEI) + +/* + * For cli() we have to insert nops to make sure that the new value + * has actually arrived in the status register before the end of this + * macro. + * R4000/R4400 need three nops, the R4600 two nops and the R10000 needs + * no nops at all. + */ +/* + * For TX49, operating only IE bit is not enough. + * + * If mfc0 $12 follows store and the mfc0 is last instruction of a + * page and fetching the next instruction causes TLB miss, the result + * of the mfc0 might wrongly contain EXL bit. + * + * ERT-TX49H2-027, ERT-TX49H3-012, ERT-TX49HL3-006, ERT-TX49H4-008 + * + * Workaround: mask EXL bit of the result or place a nop before mfc0. + */ +notrace void arch_local_irq_disable(void) +{ + preempt_disable_notrace(); + + __asm__ __volatile__( + " .set push \n" + " .set noat \n" + " mfc0 $1,$12 \n" + " ori $1,0x1f \n" + " xori $1,0x1f \n" + " .set noreorder \n" + " mtc0 $1,$12 \n" + " " __stringify(__irq_disable_hazard) " \n" + " .set pop \n" + : /* no outputs */ + : /* no inputs */ + : "memory"); + + preempt_enable_notrace(); +} +EXPORT_SYMBOL(arch_local_irq_disable); + +notrace unsigned long arch_local_irq_save(void) +{ + unsigned long flags; + + preempt_disable_notrace(); + + __asm__ __volatile__( + " .set push \n" + " .set reorder \n" + " .set noat \n" + " mfc0 %[flags], $12 \n" + " ori $1, %[flags], 0x1f \n" + " xori $1, 0x1f \n" + " .set noreorder \n" + " mtc0 $1, $12 \n" + " " __stringify(__irq_disable_hazard) " \n" + " .set pop \n" + : [flags] "=r" (flags) + : /* no inputs */ + : "memory"); + + preempt_enable_notrace(); + + return flags; +} +EXPORT_SYMBOL(arch_local_irq_save); + +notrace void arch_local_irq_restore(unsigned long flags) +{ + unsigned long __tmp1; + + preempt_disable_notrace(); + + __asm__ __volatile__( + " .set push \n" + " .set noreorder \n" + " .set noat \n" + " mfc0 $1, $12 \n" + " andi %[flags], 1 \n" + " ori $1, 0x1f \n" + " xori $1, 0x1f \n" + " or %[flags], $1 \n" + " mtc0 %[flags], $12 \n" + " " __stringify(__irq_disable_hazard) " \n" + " .set pop \n" + : [flags] "=r" (__tmp1) + : "0" (flags) + : "memory"); + + preempt_enable_notrace(); +} +EXPORT_SYMBOL(arch_local_irq_restore); + +#endif /* !CONFIG_CPU_HAS_DIEI */ -- cgit v1.3.1