Re: [RFC PATCH v1 22/33] mm/SPARC: use common help functions to freereserved pages

From: Jiang Liu
Date: Wed Mar 06 2013 - 10:57:01 EST


Hi Sam,
Thanks for review!

On 03/06/2013 03:58 AM, Sam Ravnborg wrote:
> On Tue, Mar 05, 2013 at 10:55:05PM +0800, Jiang Liu wrote:
>> Use common help functions to free reserved pages.
>
> I like how this simplify things!
>
> Please consider how you can also cover the HIGHMEM case,
> so map_high_region(...) is simplified too (in init_32.c).
>
>>
>> Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxx>
>> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
>> Cc: Sam Ravnborg <sam@xxxxxxxxxxxx>
>> ---
>> arch/sparc/kernel/leon_smp.c | 15 +++------------
>> arch/sparc/mm/init_32.c | 40 ++++++----------------------------------
>> arch/sparc/mm/init_64.c | 25 ++++---------------------
>> 3 files changed, 13 insertions(+), 67 deletions(-)
>>
>> diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
>> index 48e0c03..2a7b6eb 100644
>> --- a/arch/sparc/mm/init_32.c
>> +++ b/arch/sparc/mm/init_32.c
>> @@ -374,45 +374,17 @@ void __init mem_init(void)
>>
>> void free_initmem (void)
>> {
>> - unsigned long addr;
>> - unsigned long freed;
>> -
>> - addr = (unsigned long)(&__init_begin);
>> - freed = (unsigned long)(&__init_end) - addr;
>> - for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
>> - struct page *p;
>> -
>> - memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
>> - p = virt_to_page(addr);
>> -
>> - ClearPageReserved(p);
>> - init_page_count(p);
>> - __free_page(p);
>> - totalram_pages++;
>> - num_physpages++;
>> - }
>> - printk(KERN_INFO "Freeing unused kernel memory: %ldk freed\n",
>> - freed >> 10);
>> + num_physpages += free_reserved_area((unsigned long)(&__init_begin),
>> + (unsigned long)(&__init_end),
>> + POISON_FREE_INITMEM,
>> + "unused kernel");
> If you change free_initmem_default(...) to return number of pages freed this
> could have been used here.
Good suggestion, will make that change.

>
>> }
>>
>> #ifdef CONFIG_BLK_DEV_INITRD
>> void free_initrd_mem(unsigned long start, unsigned long end)
>> {
>> - if (start < end)
>> - printk(KERN_INFO "Freeing initrd memory: %ldk freed\n",
>> - (end - start) >> 10);
>> - for (; start < end; start += PAGE_SIZE) {
>> - struct page *p;
>> -
>> - memset((void *)start, POISON_FREE_INITMEM, PAGE_SIZE);
>> - p = virt_to_page(start);
>> -
>> - ClearPageReserved(p);
>> - init_page_count(p);
>> - __free_page(p);
>> - totalram_pages++;
>> - num_physpages++;
>> - }
>> + num_physpages += free_reserved_area(start, end, POISON_FREE_INITMEM,
>> + "initrd");
>> }
>> #endif
>>
>> diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
>> index 1588d33..03bfd10 100644
>> --- a/arch/sparc/mm/init_64.c
>> +++ b/arch/sparc/mm/init_64.c
>> @@ -2060,8 +2060,7 @@ void __init mem_init(void)
>> /* We subtract one to account for the mem_map_zero page
>> * allocated below.
>> */
>> - totalram_pages -= 1;
>> - num_physpages = totalram_pages;
>> + num_physpages = totalram_pages - 1;
>>
>> /*
>> * Set up the zero page, mark it reserved, so that page count
>> @@ -2072,7 +2071,7 @@ void __init mem_init(void)
>> prom_printf("paging_init: Cannot alloc zero page.\n");
>> prom_halt();
>> }
>> - SetPageReserved(mem_map_zero);
>> + mark_page_reserved(mem_map_zero);
>>
>> codepages = (((unsigned long) _etext) - ((unsigned long) _start));
>> codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
>> @@ -2112,7 +2111,6 @@ void free_initmem(void)
>> initend = (unsigned long)(__init_end) & PAGE_MASK;
>> for (; addr < initend; addr += PAGE_SIZE) {
>> unsigned long page;
>> - struct page *p;
>>
>> page = (addr +
>> ((unsigned long) __va(kern_base)) -
>> @@ -2120,13 +2118,8 @@ void free_initmem(void)
>> memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
>>
>> if (do_free) {
>> - p = virt_to_page(page);
>> -
>> - ClearPageReserved(p);
>> - init_page_count(p);
>> - __free_page(p);
>> + free_reserved_page(virt_to_page(page));
>> num_physpages++;
>> - totalram_pages++;
>> }
>> }
>> }
>> @@ -2134,17 +2127,7 @@ void free_initmem(void)
>> #ifdef CONFIG_BLK_DEV_INITRD
>> void free_initrd_mem(unsigned long start, unsigned long end)
>> {
>> - if (start < end)
>> - printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
>> - for (; start < end; start += PAGE_SIZE) {
>> - struct page *p = virt_to_page(start);
>> -
>> - ClearPageReserved(p);
>> - init_page_count(p);
>> - __free_page(p);
>> - num_physpages++;
>> - totalram_pages++;
>> - }
>> + num_physpages += free_reserved_area(start, end, 0, "initrd");
>
> Please add poison POISON_FREE_INITMEM here. I know this was not done before.
Sure, will make it.

>
> Sam
>

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