2019-07-15 14:46:41

by Joel Fernandes

Subject: [PATCH 8/9] acpi: Use built-in RCU list checking for acpi_ioremaps list (v1)

list_for_each_entry_rcu has built-in RCU and lock checking. Make use of
it for acpi_ioremaps list traversal.

Signed-off-by: Joel Fernandes (Google) <[email protected]>
---
drivers/acpi/osl.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 9c0edf2fc0dd..2f9d0d20b836 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -14,6 +14,7 @@
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/highmem.h>
+#include <linux/lockdep.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/kmod.h>
@@ -80,6 +81,7 @@ struct acpi_ioremap {

static LIST_HEAD(acpi_ioremaps);
static DEFINE_MUTEX(acpi_ioremap_lock);
+#define acpi_ioremap_lock_held() lock_is_held(&acpi_ioremap_lock.dep_map)

static void __init acpi_request_region (struct acpi_generic_address *gas,
unsigned int length, char *desc)
@@ -206,7 +208,7 @@ acpi_map_lookup(acpi_physical_address phys, acpi_size size)
{
struct acpi_ioremap *map;

- list_for_each_entry_rcu(map, &acpi_ioremaps, list)
+ list_for_each_entry_rcu(map, &acpi_ioremaps, list, acpi_ioremap_lock_held())
if (map->phys <= phys &&
phys + size <= map->phys + map->size)
return map;
@@ -249,7 +251,7 @@ acpi_map_lookup_virt(void __iomem *virt, acpi_size size)
{
struct acpi_ioremap *map;

- list_for_each_entry_rcu(map, &acpi_ioremaps, list)
+ list_for_each_entry_rcu(map, &acpi_ioremaps, list, acpi_ioremap_lock_held())
if (map->virt <= virt &&
virt + size <= map->virt + map->size)
return map;
--
2.22.0.510.g264f2c817a-goog

2019-07-15 21:45:21

by Rafael J. Wysocki

Subject: Re: [PATCH 8/9] acpi: Use built-in RCU list checking for acpi_ioremaps list (v1)

On Mon, Jul 15, 2019 at 4:43 PM Joel Fernandes (Google)
<[email protected]> wrote:
>
> list_for_each_entry_rcu has built-in RCU and lock checking. Make use of
> it for acpi_ioremaps list traversal.
>
> Signed-off-by: Joel Fernandes (Google) <[email protected]>

Acked-by: Rafael J. Wysocki <[email protected]>

> ---
> drivers/acpi/osl.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
> index 9c0edf2fc0dd..2f9d0d20b836 100644
> --- a/drivers/acpi/osl.c
> +++ b/drivers/acpi/osl.c
> @@ -14,6 +14,7 @@
> #include <linux/slab.h>
> #include <linux/mm.h>
> #include <linux/highmem.h>
> +#include <linux/lockdep.h>
> #include <linux/pci.h>
> #include <linux/interrupt.h>
> #include <linux/kmod.h>
> @@ -80,6 +81,7 @@ struct acpi_ioremap {
>
> static LIST_HEAD(acpi_ioremaps);
> static DEFINE_MUTEX(acpi_ioremap_lock);
> +#define acpi_ioremap_lock_held() lock_is_held(&acpi_ioremap_lock.dep_map)
>
> static void __init acpi_request_region (struct acpi_generic_address *gas,
> unsigned int length, char *desc)
> @@ -206,7 +208,7 @@ acpi_map_lookup(acpi_physical_address phys, acpi_size size)
> {
> struct acpi_ioremap *map;
>
> - list_for_each_entry_rcu(map, &acpi_ioremaps, list)
> + list_for_each_entry_rcu(map, &acpi_ioremaps, list, acpi_ioremap_lock_held())
> if (map->phys <= phys &&
> phys + size <= map->phys + map->size)
> return map;
> @@ -249,7 +251,7 @@ acpi_map_lookup_virt(void __iomem *virt, acpi_size size)
> {
> struct acpi_ioremap *map;
>
> - list_for_each_entry_rcu(map, &acpi_ioremaps, list)
> + list_for_each_entry_rcu(map, &acpi_ioremaps, list, acpi_ioremap_lock_held())
> if (map->virt <= virt &&
> virt + size <= map->virt + map->size)
> return map;
> --
> 2.22.0.510.g264f2c817a-goog
>

2019-07-16 18:45:41

by Paul E. McKenney

Subject: Re: [PATCH 8/9] acpi: Use built-in RCU list checking for acpi_ioremaps list (v1)

On Mon, Jul 15, 2019 at 10:37:04AM -0400, Joel Fernandes (Google) wrote:
> list_for_each_entry_rcu has built-in RCU and lock checking. Make use of
> it for acpi_ioremaps list traversal.
>
> Signed-off-by: Joel Fernandes (Google) <[email protected]>

Given that Rafael acked it, this one looks ready.

Thanx, Paul

> ---
> drivers/acpi/osl.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
> index 9c0edf2fc0dd..2f9d0d20b836 100644
> --- a/drivers/acpi/osl.c
> +++ b/drivers/acpi/osl.c
> @@ -14,6 +14,7 @@
> #include <linux/slab.h>
> #include <linux/mm.h>
> #include <linux/highmem.h>
> +#include <linux/lockdep.h>
> #include <linux/pci.h>
> #include <linux/interrupt.h>
> #include <linux/kmod.h>
> @@ -80,6 +81,7 @@ struct acpi_ioremap {
>
> static LIST_HEAD(acpi_ioremaps);
> static DEFINE_MUTEX(acpi_ioremap_lock);
> +#define acpi_ioremap_lock_held() lock_is_held(&acpi_ioremap_lock.dep_map)
>
> static void __init acpi_request_region (struct acpi_generic_address *gas,
> unsigned int length, char *desc)
> @@ -206,7 +208,7 @@ acpi_map_lookup(acpi_physical_address phys, acpi_size size)
> {
> struct acpi_ioremap *map;
>
> - list_for_each_entry_rcu(map, &acpi_ioremaps, list)
> + list_for_each_entry_rcu(map, &acpi_ioremaps, list, acpi_ioremap_lock_held())
> if (map->phys <= phys &&
> phys + size <= map->phys + map->size)
> return map;
> @@ -249,7 +251,7 @@ acpi_map_lookup_virt(void __iomem *virt, acpi_size size)
> {
> struct acpi_ioremap *map;
>
> - list_for_each_entry_rcu(map, &acpi_ioremaps, list)
> + list_for_each_entry_rcu(map, &acpi_ioremaps, list, acpi_ioremap_lock_held())
> if (map->virt <= virt &&
> virt + size <= map->virt + map->size)
> return map;
> --
> 2.22.0.510.g264f2c817a-goog
>