2014-11-10 19:30:10

by Luck, Tony

[permalink] [raw]
Subject: memblock: Refactor functions to set/clear MEMBLOCK_HOTPLUG

There is a lot of duplication in the rubric around actually setting or
clearing a mem region flag. Create a new helper function to do this and
reduce each of memblock_mark_hotplug() and memblock_clear_hotplug() to
a single line.

Signed-off-by: Tony Luck <[email protected]>

---

This will be useful if someone were to add a new mem region flag - which
I hope to be doing some day soon. But it looks like a plausible cleanup
even without that - so I'd like to get it out of the way now.

diff --git a/mm/memblock.c b/mm/memblock.c
index 6ecb0d937fb5..252b77bdf65e 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -715,16 +715,13 @@ int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
}

/**
- * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
- * @base: the base phys addr of the region
- * @size: the size of the region
*
- * This function isolates region [@base, @base + @size), and mark it with flag
- * MEMBLOCK_HOTPLUG.
+ * This function isolates region [@base, @base + @size), and sets/clears flag
*
* Return 0 on succees, -errno on failure.
*/
-int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
+static int __init_memblock memblock_setclr_flag(phys_addr_t base,
+ phys_addr_t size, int set, int flag)
{
struct memblock_type *type = &memblock.memory;
int i, ret, start_rgn, end_rgn;
@@ -734,37 +731,37 @@ int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
return ret;

for (i = start_rgn; i < end_rgn; i++)
- memblock_set_region_flags(&type->regions[i], MEMBLOCK_HOTPLUG);
+ if (set)
+ memblock_set_region_flags(&type->regions[i], flag);
+ else
+ memblock_clear_region_flags(&type->regions[i], flag);

memblock_merge_regions(type);
return 0;
}

/**
- * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region.
+ * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
* @base: the base phys addr of the region
* @size: the size of the region
*
- * This function isolates region [@base, @base + @size), and clear flag
- * MEMBLOCK_HOTPLUG for the isolated regions.
+ * Return 0 on succees, -errno on failure.
+ */
+int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
+{
+ return memblock_setclr_flag(base, size, 1, MEMBLOCK_HOTPLUG);
+}
+
+/**
+ * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region.
+ * @base: the base phys addr of the region
+ * @size: the size of the region
*
* Return 0 on succees, -errno on failure.
*/
int __init_memblock memblock_clear_hotplug(phys_addr_t base, phys_addr_t size)
{
- struct memblock_type *type = &memblock.memory;
- int i, ret, start_rgn, end_rgn;
-
- ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
- if (ret)
- return ret;
-
- for (i = start_rgn; i < end_rgn; i++)
- memblock_clear_region_flags(&type->regions[i],
- MEMBLOCK_HOTPLUG);
-
- memblock_merge_regions(type);
- return 0;
+ return memblock_setclr_flag(base, size, 0, MEMBLOCK_HOTPLUG);
}

/**


2014-11-12 06:44:34

by Yasuaki Ishimatsu

[permalink] [raw]
Subject: Re: memblock: Refactor functions to set/clear MEMBLOCK_HOTPLUG

(2014/11/11 4:05), [email protected] wrote:
> There is a lot of duplication in the rubric around actually setting or
> clearing a mem region flag. Create a new helper function to do this and
> reduce each of memblock_mark_hotplug() and memblock_clear_hotplug() to
> a single line.
>
> Signed-off-by: Tony Luck <[email protected]>
>
> ---

The refactoring looks good.

Thanks,
Yasuaki Ishimatsu

>
> This will be useful if someone were to add a new mem region flag - which
> I hope to be doing some day soon. But it looks like a plausible cleanup
> even without that - so I'd like to get it out of the way now.
>
> diff --git a/mm/memblock.c b/mm/memblock.c
> index 6ecb0d937fb5..252b77bdf65e 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -715,16 +715,13 @@ int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
> }
>
> /**
> - * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
> - * @base: the base phys addr of the region
> - * @size: the size of the region
> *
> - * This function isolates region [@base, @base + @size), and mark it with flag
> - * MEMBLOCK_HOTPLUG.
> + * This function isolates region [@base, @base + @size), and sets/clears flag
> *
> * Return 0 on succees, -errno on failure.
> */
> -int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
> +static int __init_memblock memblock_setclr_flag(phys_addr_t base,
> + phys_addr_t size, int set, int flag)
> {
> struct memblock_type *type = &memblock.memory;
> int i, ret, start_rgn, end_rgn;
> @@ -734,37 +731,37 @@ int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
> return ret;
>
> for (i = start_rgn; i < end_rgn; i++)
> - memblock_set_region_flags(&type->regions[i], MEMBLOCK_HOTPLUG);
> + if (set)
> + memblock_set_region_flags(&type->regions[i], flag);
> + else
> + memblock_clear_region_flags(&type->regions[i], flag);
>
> memblock_merge_regions(type);
> return 0;
> }
>
> /**
> - * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region.
> + * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
> * @base: the base phys addr of the region
> * @size: the size of the region
> *
> - * This function isolates region [@base, @base + @size), and clear flag
> - * MEMBLOCK_HOTPLUG for the isolated regions.
> + * Return 0 on succees, -errno on failure.
> + */
> +int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
> +{
> + return memblock_setclr_flag(base, size, 1, MEMBLOCK_HOTPLUG);
> +}
> +
> +/**
> + * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region.
> + * @base: the base phys addr of the region
> + * @size: the size of the region
> *
> * Return 0 on succees, -errno on failure.
> */
> int __init_memblock memblock_clear_hotplug(phys_addr_t base, phys_addr_t size)
> {
> - struct memblock_type *type = &memblock.memory;
> - int i, ret, start_rgn, end_rgn;
> -
> - ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
> - if (ret)
> - return ret;
> -
> - for (i = start_rgn; i < end_rgn; i++)
> - memblock_clear_region_flags(&type->regions[i],
> - MEMBLOCK_HOTPLUG);
> -
> - memblock_merge_regions(type);
> - return 0;
> + return memblock_setclr_flag(base, size, 0, MEMBLOCK_HOTPLUG);
> }
>
> /**
>
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