[lkml]   [2019]   [Oct]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH] mm/page_alloc: Add a reason for reserved pages in has_unmovable_pages()

On 10/03/2019 03:02 PM, Anshuman Khandual wrote:
> On 10/03/2019 02:35 PM, Qian Cai wrote:
>>> On Oct 3, 2019, at 4:10 AM, Anshuman Khandual <> wrote:
>>> Having unmovable pages on a given pageblock should be reported correctly
>>> when required with REPORT_FAILURE flag. But there can be a scenario where a
>>> reserved page in the page block will get reported as a generic "unmovable"
>>> reason code. Instead this should be changed to a more appropriate reason
>>> code like "Reserved page".
>> Isn’t this redundant as it dumps the flags in dump_page() anyway?
> Even though page flags does contain reserved bit information, the problem
> is that we are explicitly printing the reason for this page dump. In this
> case it is caused by the fact that it is a reserved page.
> page dumped because: <reason>
> The proposed change makes it explicit that the dump is caused because a
> non movable page with reserved bit set. It also helps in differentiating
> between reserved bit condition and the last one "if (found > count)"

Instead, will it better to rename the reason codes as

1. "Unmovable (CMA)"
2. "Unmovable (Reserved)"
3. "Unmovable (Private/non-LRU)"

 \ /
  Last update: 2019-10-03 11:54    [W:0.088 / U:10.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site