[PATCH 11/14] x86/UV: Move NMI support

Mike Travis
2013-03-12T19:39:44Z

[-- Attachment #1: uv-move-nmi-support.patch --]
[-- Type: text/plain, Size: 7738 bytes --]

This patch moves the UV NMI support from the x2apic file to a
new separate uv_nmi.c file in preparation for the next sequence
of patches. It minimizes bloat of the x2apic file, and has the
added benefit of putting the upcoming /sys/module parameters under
the name 'uv_nmi' instead of 'x2apic_uv_x', which was obscure.

Cc: Alex Shi <alex.shi@intel.com>
Cc: Cliff Wickman <cpw@sgi.com>
Cc: Alexander Gordeev <agordeev@redhat.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Steffen Persvold <sp@numascale.com>
Reviewed-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
---
arch/x86/include/asm/uv/uv.h | 2
arch/x86/kernel/apic/x2apic_uv_x.c | 69 -------------------------
arch/x86/platform/uv/Makefile | 2
arch/x86/platform/uv/uv_nmi.c | 101 +++++++++++++++++++++++++++++++++++++
4 files changed, 104 insertions(+), 70 deletions(-)

--- linux.orig/arch/x86/include/asm/uv/uv.h
+++ linux/arch/x86/include/asm/uv/uv.h
@@ -12,6 +12,7 @@ extern enum uv_system_type get_uv_system
extern int is_uv_system(void);
extern void uv_cpu_init(void);
extern void uv_nmi_init(void);
+extern void uv_register_nmi_notifier(void);
extern void uv_system_init(void);
extern const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask,
struct mm_struct *mm,
@@ -25,6 +26,7 @@ static inline enum uv_system_type get_uv
static inline int is_uv_system(void) { return 0; }
static inline void uv_cpu_init(void) { }
static inline void uv_system_init(void) { }
+static inline void uv_register_nmi_notifier(void) { }
static inline const struct cpumask *
uv_flush_tlb_others(const struct cpumask *cpumask, struct mm_struct *mm,
unsigned long start, unsigned long end, unsigned int cpu)
--- linux.orig/arch/x86/kernel/apic/x2apic_uv_x.c
+++ linux/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -39,12 +39,6 @@
#include <asm/emergency-restart.h>
#include <asm/nmi.h>

-/* BMC sets a bit this MMR non-zero before sending an NMI */
-#define UVH_NMI_MMR UVH_SCRATCH5
-#define UVH_NMI_MMR_CLEAR (UVH_NMI_MMR + 8)
-#define UV_NMI_PENDING_MASK (1UL << 63)
-DEFINE_PER_CPU(unsigned long, cpu_last_nmi_count);
-
DEFINE_PER_CPU(int, x2apic_extra_bits);

#define PR_DEVEL(fmt, args...) pr_devel("%s: " fmt, __func__, args)
@@ -56,7 +50,6 @@ int uv_min_hub_revision_id;
EXPORT_SYMBOL_GPL(uv_min_hub_revision_id);
unsigned int uv_apicid_hibits;
EXPORT_SYMBOL_GPL(uv_apicid_hibits);
-static DEFINE_SPINLOCK(uv_nmi_lock);

static struct apic apic_x2apic_uv_x;

@@ -795,68 +788,6 @@ void __cpuinit uv_cpu_init(void)
set_x2apic_extra_bits(uv_hub_info->pnode);
}

-/*
- * When NMI is received, print a stack trace.
- */
-int uv_handle_nmi(unsigned int reason, struct pt_regs *regs)
-{
- unsigned long real_uv_nmi;
- int bid;
-
- /*
- * Each blade has an MMR that indicates when an NMI has been sent
- * to cpus on the blade. If an NMI is detected, atomically
- * clear the MMR and update a per-blade NMI count used to
- * cause each cpu on the blade to notice a new NMI.
- */
- bid = uv_numa_blade_id();
- real_uv_nmi = (uv_read_local_mmr(UVH_NMI_MMR) & UV_NMI_PENDING_MASK);
-
- if (unlikely(real_uv_nmi)) {
- spin_lock(&uv_blade_info[bid].nmi_lock);
- real_uv_nmi = (uv_read_local_mmr(UVH_NMI_MMR) & UV_NMI_PENDING_MASK);
- if (real_uv_nmi) {
- uv_blade_info[bid].nmi_count++;
- uv_write_local_mmr(UVH_NMI_MMR_CLEAR, UV_NMI_PENDING_MASK);
- }
- spin_unlock(&uv_blade_info[bid].nmi_lock);
- }
-
- if (likely(__get_cpu_var(cpu_last_nmi_count) == uv_blade_info[bid].nmi_count))
- return NMI_DONE;
-
- __get_cpu_var(cpu_last_nmi_count) = uv_blade_info[bid].nmi_count;
-
- /*
- * Use a lock so only one cpu prints at a time.
- * This prevents intermixed output.
- */
- spin_lock(&uv_nmi_lock);
- pr_info("UV NMI stack dump cpu %u:\n", smp_processor_id());
- dump_stack();
- spin_unlock(&uv_nmi_lock);
-
- return NMI_HANDLED;
-}
-
-void uv_register_nmi_notifier(void)
-{
- if (register_nmi_handler(NMI_UNKNOWN, uv_handle_nmi, 0, "uv"))
- printk(KERN_WARNING "UV NMI handler failed to register\n");
-}
-
-void uv_nmi_init(void)
-{
- unsigned int value;
-
- /*
- * Unmask NMI on all cpus
- */
- value = apic_read(APIC_LVT1) | APIC_DM_NMI;
- value &= ~APIC_LVT_MASKED;
- apic_write(APIC_LVT1, value);
-}
-
void __init uv_system_init(void)
{
union uvh_rh_gam_config_mmr_u m_n_config;
--- linux.orig/arch/x86/platform/uv/Makefile
+++ linux/arch/x86/platform/uv/Makefile
@@ -1 +1 @@
-obj-$(CONFIG_X86_UV) += tlb_uv.o bios_uv.o uv_irq.o uv_sysfs.o uv_time.o
+obj-$(CONFIG_X86_UV) += tlb_uv.o bios_uv.o uv_irq.o uv_sysfs.o uv_time.o uv_nmi.o
--- /dev/null
+++ linux/arch/x86/platform/uv/uv_nmi.c
@@ -0,0 +1,101 @@
+/*
+ * SGI NMI support routines
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Copyright (c) 2009-2013 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (c) Mike Travis
+ */
+
+#include <linux/cpu.h>
+#include <linux/nmi.h>
+
+#include <asm/apic.h>
+#include <asm/uv/uv.h>
+#include <asm/uv/uv_hub.h>
+#include <asm/uv/uv_mmrs.h>
+
+/* BMC sets a bit this MMR non-zero before sending an NMI */
+#define UVH_NMI_MMR UVH_SCRATCH5
+#define UVH_NMI_MMR_CLEAR (UVH_NMI_MMR + 8)
+#define UV_NMI_PENDING_MASK (1UL << 63)
+DEFINE_PER_CPU(unsigned long, cpu_last_nmi_count);
+static DEFINE_SPINLOCK(uv_nmi_lock);
+
+/*
+ * When NMI is received, print a stack trace.
+ */
+int uv_handle_nmi(unsigned int reason, struct pt_regs *regs)
+{
+ unsigned long real_uv_nmi;
+ int bid;
+
+ /*
+ * Each blade has an MMR that indicates when an NMI has been sent
+ * to cpus on the blade. If an NMI is detected, atomically
+ * clear the MMR and update a per-blade NMI count used to
+ * cause each cpu on the blade to notice a new NMI.
+ */
+ bid = uv_numa_blade_id();
+ real_uv_nmi = (uv_read_local_mmr(UVH_NMI_MMR) & UV_NMI_PENDING_MASK);
+
+ if (unlikely(real_uv_nmi)) {
+ spin_lock(&uv_blade_info[bid].nmi_lock);
+ real_uv_nmi = (uv_read_local_mmr(UVH_NMI_MMR) &
+ UV_NMI_PENDING_MASK);
+ if (real_uv_nmi) {
+ uv_blade_info[bid].nmi_count++;
+ uv_write_local_mmr(UVH_NMI_MMR_CLEAR,
+ UV_NMI_PENDING_MASK);
+ }
+ spin_unlock(&uv_blade_info[bid].nmi_lock);
+ }
+
+ if (likely(__get_cpu_var(cpu_last_nmi_count) ==
+ uv_blade_info[bid].nmi_count))
+ return NMI_DONE;
+
+ __get_cpu_var(cpu_last_nmi_count) = uv_blade_info[bid].nmi_count;
+
+ /*
+ * Use a lock so only one cpu prints at a time.
+ * This prevents intermixed output.
+ */
+ spin_lock(&uv_nmi_lock);
+ pr_info("UV NMI stack dump cpu %u:\n", smp_processor_id());
+ dump_stack();
+ spin_unlock(&uv_nmi_lock);
+
+ return NMI_HANDLED;
+}
+
+void uv_register_nmi_notifier(void)
+{
+ if (register_nmi_handler(NMI_UNKNOWN, uv_handle_nmi, 0, "uv"))
+ pr_warn("UV NMI handler failed to register\n");
+}
+
+void uv_nmi_init(void)
+{
+ unsigned int value;
+
+ /*
+ * Unmask NMI on all cpus
+ */
+ value = apic_read(APIC_LVT1) | APIC_DM_NMI;
+ value &= ~APIC_LVT_MASKED;
+ apic_write(APIC_LVT1, value);
+}
+

--