diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/entry/common.c | 107 |
1 files changed, 10 insertions, 97 deletions
diff --git a/kernel/entry/common.c b/kernel/entry/common.c index 9ef63e414791..1034be02eae8 100644 --- a/kernel/entry/common.c +++ b/kernel/entry/common.c @@ -47,7 +47,7 @@ static __always_inline unsigned long __exit_to_user_mode_loop(struct pt_regs *re */ while (ti_work & EXIT_TO_USER_MODE_WORK_LOOP) { - local_irq_enable_exit_to_user(ti_work); + local_irq_enable(); if (ti_work & (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)) { if (!rseq_grant_slice_extension(ti_work & TIF_SLICE_EXT_DENY)) @@ -74,7 +74,7 @@ static __always_inline unsigned long __exit_to_user_mode_loop(struct pt_regs *re * might have changed while interrupts and preemption was * enabled above. */ - local_irq_disable_exit_to_user(); + local_irq_disable(); /* Check if any of the above work has queued a deferred wakeup */ tick_nohz_user_enter_prepare(); @@ -105,70 +105,16 @@ __always_inline unsigned long exit_to_user_mode_loop(struct pt_regs *regs, noinstr irqentry_state_t irqentry_enter(struct pt_regs *regs) { - irqentry_state_t ret = { - .exit_rcu = false, - }; - if (user_mode(regs)) { - irqentry_enter_from_user_mode(regs); - return ret; - } + irqentry_state_t ret = { + .exit_rcu = false, + }; - /* - * If this entry hit the idle task invoke ct_irq_enter() whether - * RCU is watching or not. - * - * Interrupts can nest when the first interrupt invokes softirq - * processing on return which enables interrupts. - * - * Scheduler ticks in the idle task can mark quiescent state and - * terminate a grace period, if and only if the timer interrupt is - * not nested into another interrupt. - * - * Checking for rcu_is_watching() here would prevent the nesting - * interrupt to invoke ct_irq_enter(). If that nested interrupt is - * the tick then rcu_flavor_sched_clock_irq() would wrongfully - * assume that it is the first interrupt and eventually claim - * quiescent state and end grace periods prematurely. - * - * Unconditionally invoke ct_irq_enter() so RCU state stays - * consistent. - * - * TINY_RCU does not support EQS, so let the compiler eliminate - * this part when enabled. - */ - if (!IS_ENABLED(CONFIG_TINY_RCU) && - (is_idle_task(current) || arch_in_rcu_eqs())) { - /* - * If RCU is not watching then the same careful - * sequence vs. lockdep and tracing is required - * as in irqentry_enter_from_user_mode(). - */ - lockdep_hardirqs_off(CALLER_ADDR0); - ct_irq_enter(); - instrumentation_begin(); - kmsan_unpoison_entry_regs(regs); - trace_hardirqs_off_finish(); - instrumentation_end(); - - ret.exit_rcu = true; + irqentry_enter_from_user_mode(regs); return ret; } - /* - * If RCU is watching then RCU only wants to check whether it needs - * to restart the tick in NOHZ mode. rcu_irq_enter_check_tick() - * already contains a warning when RCU is not watching, so no point - * in having another one here. - */ - lockdep_hardirqs_off(CALLER_ADDR0); - instrumentation_begin(); - kmsan_unpoison_entry_regs(regs); - rcu_irq_enter_check_tick(); - trace_hardirqs_off_finish(); - instrumentation_end(); - - return ret; + return irqentry_enter_from_kernel_mode(regs); } /** @@ -212,43 +158,10 @@ void dynamic_irqentry_exit_cond_resched(void) noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state) { - lockdep_assert_irqs_disabled(); - - /* Check whether this returns to user mode */ - if (user_mode(regs)) { + if (user_mode(regs)) irqentry_exit_to_user_mode(regs); - } else if (!regs_irqs_disabled(regs)) { - /* - * If RCU was not watching on entry this needs to be done - * carefully and needs the same ordering of lockdep/tracing - * and RCU as the return to user mode path. - */ - if (state.exit_rcu) { - instrumentation_begin(); - /* Tell the tracer that IRET will enable interrupts */ - trace_hardirqs_on_prepare(); - lockdep_hardirqs_on_prepare(); - instrumentation_end(); - ct_irq_exit(); - lockdep_hardirqs_on(CALLER_ADDR0); - return; - } - - instrumentation_begin(); - if (IS_ENABLED(CONFIG_PREEMPTION)) - irqentry_exit_cond_resched(); - - /* Covers both tracing and lockdep */ - trace_hardirqs_on(); - instrumentation_end(); - } else { - /* - * IRQ flags state is correct already. Just tell RCU if it - * was not watching on entry. - */ - if (state.exit_rcu) - ct_irq_exit(); - } + else + irqentry_exit_to_kernel_mode(regs, state); } irqentry_state_t noinstr irqentry_nmi_enter(struct pt_regs *regs) |