diff mbox series

[v3,3/8] drivers/base/memory: store mapping between MMOP_* and string in an array

Message ID 20200319131221.14044-4-david@redhat.com (mailing list archive)
State New, archived
Headers show
Series [v3,1/8] drivers/base/memory: rename MMOP_ONLINE_KEEP to MMOP_ONLINE | expand

Commit Message

David Hildenbrand March 19, 2020, 1:12 p.m. UTC 
Let's use a simple array which we can reuse soon. While at it, move the
string->mmop conversion out of the device hotplug lock.

Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
 drivers/base/memory.c | 38 +++++++++++++++++++++++---------------
 1 file changed, 23 insertions(+), 15 deletions(-)

Comments

Pankaj Gupta March 19, 2020, 4:33 p.m. UTC | #1 
> Let's use a simple array which we can reuse soon. While at it, move the
> string->mmop conversion out of the device hotplug lock.
>
> Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
> Acked-by: Michal Hocko <mhocko@suse.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Michal Hocko <mhocko@kernel.org>
> Cc: Oscar Salvador <osalvador@suse.de>
> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
> Cc: Baoquan He <bhe@redhat.com>
> Cc: Wei Yang <richard.weiyang@gmail.com>
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  drivers/base/memory.c | 38 +++++++++++++++++++++++---------------
>  1 file changed, 23 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/base/memory.c b/drivers/base/memory.c
> index e7e77cafef80..8a7f29c0bf97 100644
> --- a/drivers/base/memory.c
> +++ b/drivers/base/memory.c
> @@ -28,6 +28,24 @@
>
>  #define MEMORY_CLASS_NAME      "memory"
>
> +static const char *const online_type_to_str[] = {
> +       [MMOP_OFFLINE] = "offline",
> +       [MMOP_ONLINE] = "online",
> +       [MMOP_ONLINE_KERNEL] = "online_kernel",
> +       [MMOP_ONLINE_MOVABLE] = "online_movable",
> +};
> +
> +static int memhp_online_type_from_str(const char *str)
> +{
> +       int i;
> +
> +       for (i = 0; i < ARRAY_SIZE(online_type_to_str); i++) {
> +               if (sysfs_streq(str, online_type_to_str[i]))
> +                       return i;
> +       }
> +       return -EINVAL;
> +}
> +
>  #define to_memory_block(dev) container_of(dev, struct memory_block, dev)
>
>  static int sections_per_block;
> @@ -236,26 +254,17 @@ static int memory_subsys_offline(struct device *dev)
>  static ssize_t state_store(struct device *dev, struct device_attribute *attr,
>                            const char *buf, size_t count)
>  {
> +       const int online_type = memhp_online_type_from_str(buf);
>         struct memory_block *mem = to_memory_block(dev);
> -       int ret, online_type;
> +       int ret;
> +
> +       if (online_type < 0)
> +               return -EINVAL;
>
>         ret = lock_device_hotplug_sysfs();
>         if (ret)
>                 return ret;
>
> -       if (sysfs_streq(buf, "online_kernel"))
> -               online_type = MMOP_ONLINE_KERNEL;
> -       else if (sysfs_streq(buf, "online_movable"))
> -               online_type = MMOP_ONLINE_MOVABLE;
> -       else if (sysfs_streq(buf, "online"))
> -               online_type = MMOP_ONLINE;
> -       else if (sysfs_streq(buf, "offline"))
> -               online_type = MMOP_OFFLINE;
> -       else {
> -               ret = -EINVAL;
> -               goto err;
> -       }
> -
>         switch (online_type) {
>         case MMOP_ONLINE_KERNEL:
>         case MMOP_ONLINE_MOVABLE:
> @@ -271,7 +280,6 @@ static ssize_t state_store(struct device *dev, struct device_attribute *attr,
>                 ret = -EINVAL; /* should never happen */
>         }
>
> -err:
>         unlock_device_hotplug();
>
>         if (ret < 0)
> --

Nice cleanup patch.
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>

> 2.24.1
>
>
Baoquan He March 20, 2020, 7:36 a.m. UTC | #2 
On 03/19/20 at 02:12pm, David Hildenbrand wrote:
> Let's use a simple array which we can reuse soon. While at it, move the
> string->mmop conversion out of the device hotplug lock.
> 
> Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
> Acked-by: Michal Hocko <mhocko@suse.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Michal Hocko <mhocko@kernel.org>
> Cc: Oscar Salvador <osalvador@suse.de>
> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
> Cc: Baoquan He <bhe@redhat.com>
> Cc: Wei Yang <richard.weiyang@gmail.com>
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  drivers/base/memory.c | 38 +++++++++++++++++++++++---------------
>  1 file changed, 23 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/base/memory.c b/drivers/base/memory.c
> index e7e77cafef80..8a7f29c0bf97 100644
> --- a/drivers/base/memory.c
> +++ b/drivers/base/memory.c
> @@ -28,6 +28,24 @@
>  
>  #define MEMORY_CLASS_NAME	"memory"
>  
> +static const char *const online_type_to_str[] = {
> +	[MMOP_OFFLINE] = "offline",
> +	[MMOP_ONLINE] = "online",
> +	[MMOP_ONLINE_KERNEL] = "online_kernel",
> +	[MMOP_ONLINE_MOVABLE] = "online_movable",
> +};
> +
> +static int memhp_online_type_from_str(const char *str)
> +{
> +	int i;

I would change it as: 

	for (int i = 0; i < ARRAY_SIZE(online_type_to_str); i++) {

> +
> +	for (i = 0; i < ARRAY_SIZE(online_type_to_str); i++) {
> +		if (sysfs_streq(str, online_type_to_str[i]))
> +			return i;
> +	}
> +	return -EINVAL;
> +}
> +
>  #define to_memory_block(dev) container_of(dev, struct memory_block, dev)
>  
>  static int sections_per_block;
> @@ -236,26 +254,17 @@ static int memory_subsys_offline(struct device *dev)
>  static ssize_t state_store(struct device *dev, struct device_attribute *attr,
>  			   const char *buf, size_t count)
>  {
> +	const int online_type = memhp_online_type_from_str(buf);
>  	struct memory_block *mem = to_memory_block(dev);
> -	int ret, online_type;
> +	int ret;
> +
> +	if (online_type < 0)
> +		return -EINVAL;
>  
>  	ret = lock_device_hotplug_sysfs();
>  	if (ret)
>  		return ret;
>  
> -	if (sysfs_streq(buf, "online_kernel"))
> -		online_type = MMOP_ONLINE_KERNEL;
> -	else if (sysfs_streq(buf, "online_movable"))
> -		online_type = MMOP_ONLINE_MOVABLE;
> -	else if (sysfs_streq(buf, "online"))
> -		online_type = MMOP_ONLINE;
> -	else if (sysfs_streq(buf, "offline"))
> -		online_type = MMOP_OFFLINE;
> -	else {
> -		ret = -EINVAL;
> -		goto err;
> -	}
> -
>  	switch (online_type) {
>  	case MMOP_ONLINE_KERNEL:
>  	case MMOP_ONLINE_MOVABLE:
> @@ -271,7 +280,6 @@ static ssize_t state_store(struct device *dev, struct device_attribute *attr,
>  		ret = -EINVAL; /* should never happen */
>  	}
>  
> -err:
>  	unlock_device_hotplug();
>  
>  	if (ret < 0)
> -- 
> 2.24.1
>
David Hildenbrand March 20, 2020, 9:50 a.m. UTC | #3 
On 20.03.20 08:36, Baoquan He wrote:
> On 03/19/20 at 02:12pm, David Hildenbrand wrote:
>> Let's use a simple array which we can reuse soon. While at it, move the
>> string->mmop conversion out of the device hotplug lock.
>>
>> Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
>> Acked-by: Michal Hocko <mhocko@suse.com>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: Andrew Morton <akpm@linux-foundation.org>
>> Cc: Michal Hocko <mhocko@kernel.org>
>> Cc: Oscar Salvador <osalvador@suse.de>
>> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
>> Cc: Baoquan He <bhe@redhat.com>
>> Cc: Wei Yang <richard.weiyang@gmail.com>
>> Signed-off-by: David Hildenbrand <david@redhat.com>
>> ---
>>  drivers/base/memory.c | 38 +++++++++++++++++++++++---------------
>>  1 file changed, 23 insertions(+), 15 deletions(-)
>>
>> diff --git a/drivers/base/memory.c b/drivers/base/memory.c
>> index e7e77cafef80..8a7f29c0bf97 100644
>> --- a/drivers/base/memory.c
>> +++ b/drivers/base/memory.c
>> @@ -28,6 +28,24 @@
>>  
>>  #define MEMORY_CLASS_NAME	"memory"
>>  
>> +static const char *const online_type_to_str[] = {
>> +	[MMOP_OFFLINE] = "offline",
>> +	[MMOP_ONLINE] = "online",
>> +	[MMOP_ONLINE_KERNEL] = "online_kernel",
>> +	[MMOP_ONLINE_MOVABLE] = "online_movable",
>> +};
>> +
>> +static int memhp_online_type_from_str(const char *str)
>> +{
>> +	int i;
> 
> I would change it as: 
> 
> 	for (int i = 0; i < ARRAY_SIZE(online_type_to_str); i++) {
> 

That's not allowed by the C90 standard (and -std=gnu89).

$ gcc main.c -std=gnu89
main.c: In function 'main':
main.c:3:2: error: 'for' loop initial declarations are only allowed in
C99 or C11 mode
    3 |  for (int i = 0; i < 8; i++) {
      |  ^~~

One of the reasons why
	git grep "for (int "

will result in very little hits (IOW, only 5 in driver code only).
Baoquan He March 20, 2020, 9:59 a.m. UTC | #4 
On 03/20/20 at 10:50am, David Hildenbrand wrote:
> On 20.03.20 08:36, Baoquan He wrote:
> > On 03/19/20 at 02:12pm, David Hildenbrand wrote:
> >> Let's use a simple array which we can reuse soon. While at it, move the
> >> string->mmop conversion out of the device hotplug lock.
> >>
> >> Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
> >> Acked-by: Michal Hocko <mhocko@suse.com>
> >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> >> Cc: Andrew Morton <akpm@linux-foundation.org>
> >> Cc: Michal Hocko <mhocko@kernel.org>
> >> Cc: Oscar Salvador <osalvador@suse.de>
> >> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
> >> Cc: Baoquan He <bhe@redhat.com>
> >> Cc: Wei Yang <richard.weiyang@gmail.com>
> >> Signed-off-by: David Hildenbrand <david@redhat.com>
> >> ---
> >>  drivers/base/memory.c | 38 +++++++++++++++++++++++---------------
> >>  1 file changed, 23 insertions(+), 15 deletions(-)
> >>
> >> diff --git a/drivers/base/memory.c b/drivers/base/memory.c
> >> index e7e77cafef80..8a7f29c0bf97 100644
> >> --- a/drivers/base/memory.c
> >> +++ b/drivers/base/memory.c
> >> @@ -28,6 +28,24 @@
> >>  
> >>  #define MEMORY_CLASS_NAME	"memory"
> >>  
> >> +static const char *const online_type_to_str[] = {
> >> +	[MMOP_OFFLINE] = "offline",
> >> +	[MMOP_ONLINE] = "online",
> >> +	[MMOP_ONLINE_KERNEL] = "online_kernel",
> >> +	[MMOP_ONLINE_MOVABLE] = "online_movable",
> >> +};
> >> +
> >> +static int memhp_online_type_from_str(const char *str)
> >> +{
> >> +	int i;
> > 
> > I would change it as: 
> > 
> > 	for (int i = 0; i < ARRAY_SIZE(online_type_to_str); i++) {
> > 
> 
> That's not allowed by the C90 standard (and -std=gnu89).
> 
> $ gcc main.c -std=gnu89
> main.c: In function 'main':
> main.c:3:2: error: 'for' loop initial declarations are only allowed in
> C99 or C11 mode
>     3 |  for (int i = 0; i < 8; i++) {
>       |  ^~~

Good to know, thanks.

> 
> One of the reasons why
> 	git grep "for (int "
> 
> will result in very little hits (IOW, only 5 in driver code only).
> 
> -- 
> Thanks,
> 
> David / dhildenb
diff mbox series

Patch

diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index e7e77cafef80..8a7f29c0bf97 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -28,6 +28,24 @@ 
 
 #define MEMORY_CLASS_NAME	"memory"
 
+static const char *const online_type_to_str[] = {
+	[MMOP_OFFLINE] = "offline",
+	[MMOP_ONLINE] = "online",
+	[MMOP_ONLINE_KERNEL] = "online_kernel",
+	[MMOP_ONLINE_MOVABLE] = "online_movable",
+};
+
+static int memhp_online_type_from_str(const char *str)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(online_type_to_str); i++) {
+		if (sysfs_streq(str, online_type_to_str[i]))
+			return i;
+	}
+	return -EINVAL;
+}
+
 #define to_memory_block(dev) container_of(dev, struct memory_block, dev)
 
 static int sections_per_block;
@@ -236,26 +254,17 @@  static int memory_subsys_offline(struct device *dev)
 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
 			   const char *buf, size_t count)
 {
+	const int online_type = memhp_online_type_from_str(buf);
 	struct memory_block *mem = to_memory_block(dev);
-	int ret, online_type;
+	int ret;
+
+	if (online_type < 0)
+		return -EINVAL;
 
 	ret = lock_device_hotplug_sysfs();
 	if (ret)
 		return ret;
 
-	if (sysfs_streq(buf, "online_kernel"))
-		online_type = MMOP_ONLINE_KERNEL;
-	else if (sysfs_streq(buf, "online_movable"))
-		online_type = MMOP_ONLINE_MOVABLE;
-	else if (sysfs_streq(buf, "online"))
-		online_type = MMOP_ONLINE;
-	else if (sysfs_streq(buf, "offline"))
-		online_type = MMOP_OFFLINE;
-	else {
-		ret = -EINVAL;
-		goto err;
-	}
-
 	switch (online_type) {
 	case MMOP_ONLINE_KERNEL:
 	case MMOP_ONLINE_MOVABLE:
@@ -271,7 +280,6 @@  static ssize_t state_store(struct device *dev, struct device_attribute *attr,
 		ret = -EINVAL; /* should never happen */
 	}
 
-err:
 	unlock_device_hotplug();
 
 	if (ret < 0)