lkml.org 
[lkml]   [2019]   [Dec]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [Patch v2 4/6] x86/mm: Refine debug print string retrieval function
On Thu, Dec 05, 2019 at 10:13:11AM +0100, Peter Zijlstra wrote:
>On Thu, Dec 05, 2019 at 10:14:01AM +0800, Wei Yang wrote:
>> Generally, the mapping page size are:
>>
>> 4K, 2M, 1G
>>
>> except in case 32-bit without PAE, the mapping page size are:
>>
>> 4K, 4M
>>
>> Based on PG_LEVEL_X definition and mr->page_size_mask, we can calculate
>> the mapping page size from a predefined string array.
>>
>> Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
>> ---
>> arch/x86/mm/init.c | 39 +++++++++++++--------------------------
>> 1 file changed, 13 insertions(+), 26 deletions(-)
>>
>> diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
>> index 0eb5edb63fa2..ded58a31c679 100644
>> --- a/arch/x86/mm/init.c
>> +++ b/arch/x86/mm/init.c
>> @@ -308,29 +308,20 @@ static void __ref adjust_range_page_size_mask(struct map_range *mr,
>> }
>> }
>>
>> +static void __meminit mr_print(struct map_range *mr, unsigned int maxidx)
>> {
>> +#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_PAE)
>> + static const char *sz[2] = { "4K", "4M" };
>> +#else
>> + static const char *sz[4] = { "4K", "2M", "1G", "" };
>> +#endif
>> + unsigned int idx, s;
>>
>> + for (idx = 0; idx < maxidx; idx++, mr++) {
>> + s = (mr->page_size_mask >> PG_LEVEL_2M) & (ARRAY_SIZE(sz) - 1);
>
>Is it at all possible for !PAE to have 1G here, if you use the sz[4]
>definition unconditionally?
>

You mean remove the ifdef and use sz[4] for both condition?

Then how to differentiate 4M and 2M?

>> + pr_debug(" [mem %#010lx-%#010lx] page size %s\n",
>> + mr->start, mr->end - 1, sz[s]);
>> + }
>> }

--
Wei Yang
Help you, Help me

\
 
 \ /
  Last update: 2019-12-06 02:52    [W:0.046 / U:6.920 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site