linux-kernel - [PATCH 2/5] xtensa: move trace_hardirqs

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Message-Id: <20220418171205.2413168-3-jcmvbkbc@gmail.com>
Date:   Mon, 18 Apr 2022 10:12:02 -0700
From:   Max Filippov <jcmvbkbc@...il.com>
To:     linux-xtensa@...ux-xtensa.org
Cc:     Chris Zankel <chris@...kel.net>, linux-kernel@...r.kernel.org,
        Max Filippov <jcmvbkbc@...il.com>
Subject: [PATCH 2/5] xtensa: move trace_hardirqs_off call back to entry.S

Context tracking call must be done after hardirq tracking call,
otherwise lockdep_assert_irqs_disabled called from rcu_eqs_exit gives
a warning. To avoid context tracking logic duplication for IRQ/exception
entry paths move trace_hardirqs_off call back to common entry code.

Signed-off-by: Max Filippov <jcmvbkbc@...il.com>
---
 arch/xtensa/kernel/entry.S | 19 +++++++++++++------
 arch/xtensa/kernel/traps.c | 11 ++---------
 2 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 3c0b1aac7aba..c85597a734aa 100644
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -424,7 +424,6 @@ KABI_W	or	a3, a3, a0
 	moveqz	a3, a0, a2		# a3 = LOCKLEVEL iff interrupt
 KABI_W	movi	a2, PS_WOE_MASK
 KABI_W	or	a3, a3, a2
-	rsr	a2, exccause
 #endif
 
 	/* restore return address (or 0 if return to userspace) */
@@ -451,19 +450,27 @@ KABI_W	or	a3, a3, a2
 
 	save_xtregs_opt a1 a3 a4 a5 a6 a7 PT_XTREGS_OPT
 	
+#ifdef CONFIG_TRACE_IRQFLAGS
+	rsr		abi_tmp0, ps
+	extui		abi_tmp0, abi_tmp0, PS_INTLEVEL_SHIFT, PS_INTLEVEL_WIDTH
+	beqz		abi_tmp0, 1f
+	abi_call	trace_hardirqs_off
+1:
+#endif
+
 	/* Go to second-level dispatcher. Set up parameters to pass to the
 	 * exception handler and call the exception handler.
 	 */
 
-	rsr	a4, excsave1
-	addx4	a4, a2, a4
-	l32i	a4, a4, EXC_TABLE_DEFAULT		# load handler
-	mov	abi_arg1, a2			# pass EXCCAUSE
+	l32i	abi_arg1, a1, PT_EXCCAUSE	# pass EXCCAUSE
+	rsr	abi_tmp0, excsave1
+	addx4	abi_tmp0, abi_arg1, abi_tmp0
+	l32i	abi_tmp0, abi_tmp0, EXC_TABLE_DEFAULT	# load handler
 	mov	abi_arg0, a1			# pass stack frame
 
 	/* Call the second-level handler */
 
-	abi_callx	a4
+	abi_callx	abi_tmp0
 
 	/* Jump here for exception exit */
 	.global common_exception_return
diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c
index 82ced7b25b77..515719c7e750 100644
--- a/arch/xtensa/kernel/traps.c
+++ b/arch/xtensa/kernel/traps.c
@@ -242,12 +242,8 @@ DEFINE_PER_CPU(unsigned long, nmi_count);
 
 void do_nmi(struct pt_regs *regs)
 {
-	struct pt_regs *old_regs;
+	struct pt_regs *old_regs = set_irq_regs(regs);
 
-	if ((regs->ps & PS_INTLEVEL_MASK) < LOCKLEVEL)
-		trace_hardirqs_off();
-
-	old_regs = set_irq_regs(regs);
 	nmi_enter();
 	++*this_cpu_ptr(&nmi_count);
 	check_valid_nmi();
@@ -269,12 +265,9 @@ void do_interrupt(struct pt_regs *regs)
 		XCHAL_INTLEVEL6_MASK,
 		XCHAL_INTLEVEL7_MASK,
 	};
-	struct pt_regs *old_regs;
+	struct pt_regs *old_regs = set_irq_regs(regs);
 	unsigned unhandled = ~0u;
 
-	trace_hardirqs_off();
-
-	old_regs = set_irq_regs(regs);
 	irq_enter();
 
 	for (;;) {
-- 
2.30.2