diff mbox

[v10,4/6] mm: function to offer a page block on the free list

Message ID 1493887815-6070-5-git-send-email-wei.w.wang@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Wang, Wei W May 4, 2017, 8:50 a.m. UTC
Add a function to find a page block on the free list specified by the
caller. Pages from the page block may be used immediately after the
function returns. The caller is responsible for detecting or preventing
the use of such pages.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Liang Li <liang.z.li@intel.com>
---
 include/linux/mm.h |  5 +++
 mm/page_alloc.c    | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 96 insertions(+)

Comments

kernel test robot May 5, 2017, 12:21 a.m. UTC | #1
Hi Wei,

[auto build test WARNING on linus/master]
[also build test WARNING on v4.11 next-20170504]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Wei-Wang/Extend-virtio-balloon-for-fast-de-inflating-fast-live-migration/20170505-052958
reproduce: make htmldocs

All warnings (new ones prefixed by >>):

   WARNING: convert(1) not found, for SVG to PDF conversion install ImageMagick (https://www.imagemagick.org)
   arch/x86/include/asm/uaccess_32.h:1: warning: no structured comments found
>> mm/page_alloc.c:4663: warning: No description found for parameter 'zone'
>> mm/page_alloc.c:4663: warning: No description found for parameter 'order'
>> mm/page_alloc.c:4663: warning: No description found for parameter 'migratetype'
>> mm/page_alloc.c:4663: warning: No description found for parameter 'page'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
   include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
   include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'

vim +/zone +4663 mm/page_alloc.c

  4647	 * Heuristically get a page block in the system that is unused.
  4648	 * It is possible that pages from the page block are used immediately after
  4649	 * report_unused_page_block() returns. It is the caller's responsibility
  4650	 * to either detect or prevent the use of such pages.
  4651	 *
  4652	 * The free list to check: zone->free_area[order].free_list[migratetype].
  4653	 *
  4654	 * If the caller supplied page block (i.e. **page) is on the free list, offer
  4655	 * the next page block on the list to the caller. Otherwise, offer the first
  4656	 * page block on the list.
  4657	 *
  4658	 * Return 0 when a page block is found on the caller specified free list.
  4659	 */
  4660	int report_unused_page_block(struct zone *zone, unsigned int order,
  4661				     unsigned int migratetype, struct page **page)
  4662	{
> 4663		struct zone *this_zone;
  4664		struct list_head *this_list;
  4665		int ret = 0;
  4666		unsigned long flags;
  4667	
  4668		/* Sanity check */
  4669		if (zone == NULL || page == NULL || order >= MAX_ORDER ||
  4670		    migratetype >= MIGRATE_TYPES)
  4671			return -EINVAL;

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
Michael S. Tsirkin May 5, 2017, 10:12 p.m. UTC | #2
On Fri, May 05, 2017 at 08:21:34AM +0800, kbuild test robot wrote:
> Hi Wei,
> 
> [auto build test WARNING on linus/master]
> [also build test WARNING on v4.11 next-20170504]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
> 
> url:    https://github.com/0day-ci/linux/commits/Wei-Wang/Extend-virtio-balloon-for-fast-de-inflating-fast-live-migration/20170505-052958
> reproduce: make htmldocs
> 
> All warnings (new ones prefixed by >>):
> 
>    WARNING: convert(1) not found, for SVG to PDF conversion install ImageMagick (https://www.imagemagick.org)
>    arch/x86/include/asm/uaccess_32.h:1: warning: no structured comments found
> >> mm/page_alloc.c:4663: warning: No description found for parameter 'zone'
> >> mm/page_alloc.c:4663: warning: No description found for parameter 'order'
> >> mm/page_alloc.c:4663: warning: No description found for parameter 'migratetype'
> >> mm/page_alloc.c:4663: warning: No description found for parameter 'page'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
>    include/net/cfg80211.h:1738: warning: No description found for parameter 'report_results'
>    include/net/cfg80211.h:1738: warning: Excess struct/union/enum/typedef member 'results_wk' description in 'cfg80211_sched_scan_request'
> 
> vim +/zone +4663 mm/page_alloc.c

the issue is actually aboe this line: it is:

/**

which is reserved for kernel-doc.

Either format properly for kernel-doc, or use simple /*
to start comments.


>   4647	 * Heuristically get a page block in the system that is unused.
>   4648	 * It is possible that pages from the page block are used immediately after
>   4649	 * report_unused_page_block() returns. It is the caller's responsibility
>   4650	 * to either detect or prevent the use of such pages.
>   4651	 *
>   4652	 * The free list to check: zone->free_area[order].free_list[migratetype].
>   4653	 *
>   4654	 * If the caller supplied page block (i.e. **page) is on the free list, offer
>   4655	 * the next page block on the list to the caller. Otherwise, offer the first
>   4656	 * page block on the list.
>   4657	 *
>   4658	 * Return 0 when a page block is found on the caller specified free list.
>   4659	 */
>   4660	int report_unused_page_block(struct zone *zone, unsigned int order,
>   4661				     unsigned int migratetype, struct page **page)
>   4662	{
> > 4663		struct zone *this_zone;
>   4664		struct list_head *this_list;
>   4665		int ret = 0;
>   4666		unsigned long flags;
>   4667	
>   4668		/* Sanity check */
>   4669		if (zone == NULL || page == NULL || order >= MAX_ORDER ||
>   4670		    migratetype >= MIGRATE_TYPES)
>   4671			return -EINVAL;
> 
> ---
> 0-DAY kernel test infrastructure                Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
diff mbox

Patch

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 5d22e69..82361a6 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1841,6 +1841,11 @@  extern void free_area_init_node(int nid, unsigned long * zones_size,
 		unsigned long zone_start_pfn, unsigned long *zholes_size);
 extern void free_initmem(void);
 
+#if IS_ENABLED(CONFIG_VIRTIO_BALLOON)
+extern int report_unused_page_block(struct zone *zone, unsigned int order,
+				    unsigned int migratetype,
+				    struct page **page);
+#endif
 /*
  * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
  * into the buddy system. The freed pages will be poisoned with pattern
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2c25de4..e554ab8 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4615,6 +4615,97 @@  void show_free_areas(unsigned int filter, nodemask_t *nodemask)
 	show_swap_cache_info();
 }
 
+#if IS_ENABLED(CONFIG_VIRTIO_BALLOON)
+
+/**
+ * Heuristically get a page block in the system that is unused.
+ * It is possible that pages from the page block are used immediately after
+ * report_unused_page_block() returns. It is the caller's responsibility
+ * to either detect or prevent the use of such pages.
+ *
+ * The free list to check: zone->free_area[order].free_list[migratetype].
+ *
+ * If the caller supplied page block (i.e. **page) is on the free list, offer
+ * the next page block on the list to the caller. Otherwise, offer the first
+ * page block on the list.
+ *
+ * Return 0 when a page block is found on the caller specified free list.
+ */
+int report_unused_page_block(struct zone *zone, unsigned int order,
+			     unsigned int migratetype, struct page **page)
+{
+	struct zone *this_zone;
+	struct list_head *this_list;
+	int ret = 0;
+	unsigned long flags;
+
+	/* Sanity check */
+	if (zone == NULL || page == NULL || order >= MAX_ORDER ||
+	    migratetype >= MIGRATE_TYPES)
+		return -EINVAL;
+
+	/* Zone validity check */
+	for_each_populated_zone(this_zone) {
+		if (zone == this_zone)
+			break;
+	}
+
+	/* Got a non-existent zone from the caller? */
+	if (zone != this_zone)
+		return -EINVAL;
+
+	spin_lock_irqsave(&this_zone->lock, flags);
+
+	this_list = &zone->free_area[order].free_list[migratetype];
+	if (list_empty(this_list)) {
+		*page = NULL;
+		ret = 1;
+		goto out;
+	}
+
+	/* The caller is asking for the first free page block on the list */
+	if ((*page) == NULL) {
+		*page = list_first_entry(this_list, struct page, lru);
+		ret = 0;
+		goto out;
+	}
+
+	/**
+	 * The page block passed from the caller is not on this free list
+	 * anymore (e.g. a 1MB free page block has been split). In this case,
+	 * offer the first page block on the free list that the caller is
+	 * asking for.
+	 */
+	if (PageBuddy(*page) && order != page_order(*page)) {
+		*page = list_first_entry(this_list, struct page, lru);
+		ret = 0;
+		goto out;
+	}
+
+	/**
+	 * The page block passed from the caller has been the last page block
+	 * on the list.
+	 */
+	if ((*page)->lru.next == this_list) {
+		*page = NULL;
+		ret = 1;
+		goto out;
+	}
+
+	/**
+	 * Finally, fall into the regular case: the page block passed from the
+	 * caller is still on the free list. Offer the next one.
+	 */
+	*page = list_next_entry((*page), lru);
+	ret = 0;
+out:
+	spin_unlock_irqrestore(&this_zone->lock, flags);
+	return ret;
+}
+EXPORT_SYMBOL(report_unused_page_block);
+
+#endif
+
 static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref)
 {
 	zoneref->zone = zone;