Re: [PATCH 2/5] mm/page_alloc: Add a bulk page allocator

On Wed, 10 Mar 2021 11:38:36 +0000
Mel Gorman [off-list ref] wrote:

On Wed, Mar 10, 2021 at 01:04:17PM +0200, Shay Agroskin wrote:

quoted

Mel Gorman [off-list ref] writes:
  

quoted

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 8572a1474e16..4903d1cc48dc 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h

@@ -515,6 +515,10 @@ static inline int arch_make_page_accessible(struct

page *page)
 }
 #endif
  +int __alloc_pages_bulk_nodemask(gfp_t gfp_mask, int preferred_nid,
+				nodemask_t *nodemask, int nr_pages,
+				struct list_head *list);
+
 struct page *
 __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int
preferred_nid,
 							nodemask_t  *nodemask);

@@ -525,6 +529,14 @@ __alloc_pages(gfp_t gfp_mask, unsigned int order,

int preferred_nid)
 	return __alloc_pages_nodemask(gfp_mask, order,  preferred_nid, NULL);
 }
+/* Bulk allocate order-0 pages */
+static inline unsigned long
+alloc_pages_bulk(gfp_t gfp_mask, unsigned long nr_pages, struct
list_head *list)
+{
+	return __alloc_pages_bulk_nodemask(gfp_mask, numa_mem_id(), NULL,
+							nr_pages, list);  

Is the second line indentation intentional ? Why not align it to the first
argument (gfp_mask) ?
  

No particular reason. I usually pick this as it's visually clearer to me
that it's part of the same line when the multi-line is part of an if block.

quoted

quoted

+}
+

[...]

quoted

Same indentation comment as before
  

Again, simple personal perference to avoid any possibility it's mixed
up with a later line. There has not been consistent code styling
enforcement of what indentation style should be used for a multi-line
within mm/page_alloc.c

Hi Shay, it is might be surprising that indentation style actually
differs slightly in different parts of the kernel.  I started in
networking area of the kernel, and I was also surprised when I started
working in MM area that the coding style differs.  I can tell you that
the indentation style Mel choose is consistent with the code styling in
MM area.  I usually respect that even-though I prefer the networking
style as I was "raised" with that style.

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer