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Subject[patch V9 12/39] x86/entry: Split out idtentry_exit_cond_resched()
The XEN PV hypercall requires the ability of conditional rescheduling when
preemption is disabled because some hypercalls take ages.

Split out the rescheduling code from idtentry_exit_cond_rcu() so it can
be reused for that.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
V9: New patch
---
arch/x86/entry/common.c | 30 +++++++++++++++---------------
1 file changed, 15 insertions(+), 15 deletions(-)

--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -580,6 +580,20 @@ bool noinstr idtentry_enter_cond_rcu(str
return false;
}

+static void idtentry_exit_cond_resched(struct pt_regs *regs, bool may_sched)
+{
+ if (may_sched && !preempt_count()) {
+ /* Sanity check RCU and thread stack */
+ rcu_irq_exit_check_preempt();
+ if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
+ WARN_ON_ONCE(!on_thread_stack());
+ if (need_resched())
+ preempt_schedule_irq();
+ }
+ /* Covers both tracing and lockdep */
+ trace_hardirqs_on();
+}
+
/**
* idtentry_exit_cond_rcu - Handle return from exception with conditional RCU
* handling
@@ -621,21 +635,7 @@ void noinstr idtentry_exit_cond_rcu(stru
}

instrumentation_begin();
-
- /* Check kernel preemption, if enabled */
- if (IS_ENABLED(CONFIG_PREEMPTION)) {
- if (!preempt_count()) {
- /* Sanity check RCU and thread stack */
- rcu_irq_exit_check_preempt();
- if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
- WARN_ON_ONCE(!on_thread_stack());
- if (need_resched())
- preempt_schedule_irq();
- }
- }
- /* Covers both tracing and lockdep */
- trace_hardirqs_on();
-
+ idtentry_exit_cond_resched(regs, IS_ENABLED(CONFIG_PREEMPTION));
instrumentation_end();
} else {
/*
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