[PATCH 4/7] acpi, apei, ghes: Factor out NMI error notification context.

Tomasz Nowicki
2014-04-09T15:14:32Z

Use CONFIG_ACPI_APEI_NMI to isolate NMI error notification path. NMI related
data and functions are grouped so they can be wrapped inside one

Signed-off-by: Tomasz Nowicki <tomasz.nowicki@linaro.org>
---
drivers/acpi/apei/ghes.c | 54 +++++++++++++++++++++++++---------------------
1 file changed, 30 insertions(+), 24 deletions(-)

diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index ca8387e..7a0d66e 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -53,7 +53,9 @@
#include <asm/mce.h>
#endif
#include <asm/tlbflush.h>
+#ifdef CONFIG_ACPI_APEI_NMI
#include <asm/nmi.h>
+#endif

#include "apei-internal.h"

@@ -88,8 +90,6 @@
bool ghes_disable;
module_param_named(disable, ghes_disable, bool, 0);

-static int ghes_panic_timeout __read_mostly = 30;
-
/*
* All error sources notified with SCI shares one notifier function,
* so they need to be linked and checked one by one. This is applied
@@ -99,16 +99,9 @@ static int ghes_panic_timeout __read_mostly = 30;
* list changing, not for traversing.
*/
static LIST_HEAD(ghes_sci);
-static LIST_HEAD(ghes_nmi);
static DEFINE_MUTEX(ghes_list_mutex);

/*
- * NMI may be triggered on any CPU, so ghes_nmi_lock is used for
- * mutual exclusion.
- */
-static DEFINE_RAW_SPINLOCK(ghes_nmi_lock);
-
-/*
* Because the memory area used to transfer hardware error information
* from BIOS to Linux can be determined only in NMI, IRQ or timer
* handler, but general ioremap can not be used in atomic context, so
@@ -132,18 +125,8 @@ static struct vm_struct *ghes_ioremap_area;
static DEFINE_RAW_SPINLOCK(ghes_ioremap_lock_nmi);
static DEFINE_SPINLOCK(ghes_ioremap_lock_irq);

-/*
- * printk is not safe in NMI context. So in NMI handler, we allocate
- * required memory from lock-less memory allocator
- * (ghes_estatus_pool), save estatus into it, put them into lock-less
- * list (ghes_estatus_llist), then delay printk into IRQ context via
- * irq_work (ghes_proc_irq_work). ghes_estatus_size_request record
- * required pool size by all NMI error source.
- */
static struct gen_pool *ghes_estatus_pool;
static unsigned long ghes_estatus_pool_size_request;
-static struct llist_head ghes_estatus_llist;
-static struct irq_work ghes_proc_irq_work;

struct ghes_estatus_cache *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE];
static atomic_t ghes_estatus_cache_alloced;
@@ -259,11 +242,6 @@ static int ghes_estatus_pool_expand(unsigned long len)
return 0;
}

-static void ghes_estatus_pool_shrink(unsigned long len)
-{
- ghes_estatus_pool_size_request -= PAGE_ALIGN(len);
-}
-
static struct ghes *ghes_new(struct acpi_hest_generic *generic)
{
struct ghes *ghes;
@@ -744,6 +722,28 @@ static int ghes_notify_sci(struct notifier_block *this,
return ret;
}

+#ifdef CONFIG_ACPI_APEI_NMI
+/*
+ * printk is not safe in NMI context. So in NMI handler, we allocate
+ * required memory from lock-less memory allocator
+ * (ghes_estatus_pool), save estatus into it, put them into lock-less
+ * list (ghes_estatus_llist), then delay printk into IRQ context via
+ * irq_work (ghes_proc_irq_work). ghes_estatus_size_request record
+ * required pool size by all NMI error source.
+ */
+static struct llist_head ghes_estatus_llist;
+static struct irq_work ghes_proc_irq_work;
+
+/*
+ * NMI may be triggered on any CPU, so ghes_nmi_lock is used for
+ * mutual exclusion.
+ */
+static DEFINE_RAW_SPINLOCK(ghes_nmi_lock);
+
+static LIST_HEAD(ghes_nmi);
+
+static int ghes_panic_timeout __read_mostly = 30;
+
static struct llist_node *llist_nodes_reverse(struct llist_node *llnode)
{
struct llist_node *next, *tail = NULL;
@@ -902,6 +902,12 @@ static unsigned long ghes_esource_prealloc_size(
return prealloc_size;
}

+static void ghes_estatus_pool_shrink(unsigned long len)
+{
+ ghes_estatus_pool_size_request -= PAGE_ALIGN(len);
+}
+#endif
+
static int ghes_notify_init_nmi(struct ghes *ghes)
{
unsigned long len;
--
1.7.9.5