linux/debian/patches/features/all/rt/0002-x86-Call-idle-notifier...

153 lines
5.5 KiB
Diff

From 35ae5a058eec4261a05eea67efc7f76178d40e7a Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker <fweisbec@gmail.com>
Date: Mon, 26 Sep 2011 12:19:11 +0200
Subject: [PATCH 002/287] x86: Call idle notifier after irq_enter()
Interrupts notify the idle exit state before calling irq_enter(). But
the notifier code calls rcu_read_lock() and this is not allowed while
rcu is in an extended quiescent state. We need to wait for
rcu_irq_enter() to be called before doing so otherwise this results in
a grumpy RCU:
[ 0.099991] WARNING: at include/linux/rcupdate.h:194 __atomic_notifier_call_chain+0xd2/0x110()
[ 0.099991] Hardware name: AMD690VM-FMH
[ 0.099991] Modules linked in:
[ 0.099991] Pid: 0, comm: swapper Not tainted 3.0.0-rc6+ #255
[ 0.099991] Call Trace:
[ 0.099991] <IRQ> [<ffffffff81051c8a>] warn_slowpath_common+0x7a/0xb0
[ 0.099991] [<ffffffff81051cd5>] warn_slowpath_null+0x15/0x20
[ 0.099991] [<ffffffff817d6fa2>] __atomic_notifier_call_chain+0xd2/0x110
[ 0.099991] [<ffffffff817d6ff1>] atomic_notifier_call_chain+0x11/0x20
[ 0.099991] [<ffffffff81001873>] exit_idle+0x43/0x50
[ 0.099991] [<ffffffff81020439>] smp_apic_timer_interrupt+0x39/0xa0
[ 0.099991] [<ffffffff817da253>] apic_timer_interrupt+0x13/0x20
[ 0.099991] <EOI> [<ffffffff8100ae67>] ? default_idle+0xa7/0x350
[ 0.099991] [<ffffffff8100ae65>] ? default_idle+0xa5/0x350
[ 0.099991] [<ffffffff8100b19b>] amd_e400_idle+0x8b/0x110
[ 0.099991] [<ffffffff810cb01f>] ? rcu_enter_nohz+0x8f/0x160
[ 0.099991] [<ffffffff810019a0>] cpu_idle+0xb0/0x110
[ 0.099991] [<ffffffff817a7505>] rest_init+0xe5/0x140
[ 0.099991] [<ffffffff817a7468>] ? rest_init+0x48/0x140
[ 0.099991] [<ffffffff81cc5ca3>] start_kernel+0x3d1/0x3dc
[ 0.099991] [<ffffffff81cc5321>] x86_64_start_reservations+0x131/0x135
[ 0.099991] [<ffffffff81cc5412>] x86_64_start_kernel+0xed/0xf4
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20110929194047.GA10247@linux.vnet.ibm.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Henroid <andrew.d.henroid@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/kernel/apic/apic.c | 6 +++---
arch/x86/kernel/apic/io_apic.c | 2 +-
arch/x86/kernel/cpu/mcheck/therm_throt.c | 2 +-
arch/x86/kernel/cpu/mcheck/threshold.c | 2 +-
arch/x86/kernel/irq.c | 6 +++---
5 files changed, 9 insertions(+), 9 deletions(-)
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index c4e3581..c2beffe 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -876,8 +876,8 @@ void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs)
* Besides, if we don't timer interrupts ignore the global
* interrupt lock, which is the WrongThing (tm) to do.
*/
- exit_idle();
irq_enter();
+ exit_idle();
local_apic_timer_interrupt();
irq_exit();
@@ -1813,8 +1813,8 @@ void smp_spurious_interrupt(struct pt_regs *regs)
{
u32 v;
- exit_idle();
irq_enter();
+ exit_idle();
/*
* Check if this really is a spurious interrupt and ACK it
* if it is a vectored one. Just in case...
@@ -1850,8 +1850,8 @@ void smp_error_interrupt(struct pt_regs *regs)
"Illegal register address", /* APIC Error Bit 7 */
};
- exit_idle();
irq_enter();
+ exit_idle();
/* First tickle the hardware, only then report what went on. -- REW */
v0 = apic_read(APIC_ESR);
apic_write(APIC_ESR, 0);
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 6d939d7..8980555 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2421,8 +2421,8 @@ asmlinkage void smp_irq_move_cleanup_interrupt(void)
unsigned vector, me;
ack_APIC_irq();
- exit_idle();
irq_enter();
+ exit_idle();
me = smp_processor_id();
for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
diff --git a/arch/x86/kernel/cpu/mcheck/therm_throt.c b/arch/x86/kernel/cpu/mcheck/therm_throt.c
index 787e06c..ce21561 100644
--- a/arch/x86/kernel/cpu/mcheck/therm_throt.c
+++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c
@@ -397,8 +397,8 @@ static void (*smp_thermal_vector)(void) = unexpected_thermal_interrupt;
asmlinkage void smp_thermal_interrupt(struct pt_regs *regs)
{
- exit_idle();
irq_enter();
+ exit_idle();
inc_irq_stat(irq_thermal_count);
smp_thermal_vector();
irq_exit();
diff --git a/arch/x86/kernel/cpu/mcheck/threshold.c b/arch/x86/kernel/cpu/mcheck/threshold.c
index d746df2..aa578ca 100644
--- a/arch/x86/kernel/cpu/mcheck/threshold.c
+++ b/arch/x86/kernel/cpu/mcheck/threshold.c
@@ -19,8 +19,8 @@ void (*mce_threshold_vector)(void) = default_threshold_interrupt;
asmlinkage void smp_threshold_interrupt(void)
{
- exit_idle();
irq_enter();
+ exit_idle();
inc_irq_stat(irq_threshold_count);
mce_threshold_vector();
irq_exit();
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 429e0c9..5d31e5b 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -181,8 +181,8 @@ unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
unsigned vector = ~regs->orig_ax;
unsigned irq;
- exit_idle();
irq_enter();
+ exit_idle();
irq = __this_cpu_read(vector_irq[vector]);
@@ -209,10 +209,10 @@ void smp_x86_platform_ipi(struct pt_regs *regs)
ack_APIC_irq();
- exit_idle();
-
irq_enter();
+ exit_idle();
+
inc_irq_stat(x86_platform_ipis);
if (x86_platform_ipi_callback)