[4/5] fs/proc/page: use a folio in stable_page_flags()

Commit Message

Kefeng Wang Nov. 3, 2023, 7:29 a.m. UTC

Replace ten compound_head() calls with one page_folio().

Signed-off-by: Kefeng Wang <[e-mail]>
---
 fs/proc/page.c | 22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

Comments

Matthew Wilcox Nov. 3, 2023, 12:28 p.m. UTC | #1

On Fri, Nov 03, 2023 at 03:29:05PM +0800, Kefeng Wang wrote:
> Replace ten compound_head() calls with one page_folio().

This is going to conflict with Gregory Price's work:

https://lore.kernel.org/linux-mm/[e-mail]/

Perhaps the two of you can collaborate on a patch series?

>  	u |= kpf_copy_bit(k, KPF_SLAB,		PG_slab);
> -	if (PageTail(page) && PageSlab(page))
> +	if (PageTail(page) && folio_test_slab(folio))
>  		u |= 1 << KPF_SLAB;

This doesn't make sense ...

Kefeng Wang Nov. 3, 2023, 1:07 p.m. UTC | #2

On 2023/11/3 20:28, Matthew Wilcox wrote:
> On Fri, Nov 03, 2023 at 03:29:05PM +0800, Kefeng Wang wrote:
>> Replace ten compound_head() calls with one page_folio().
> 
> This is going to conflict with Gregory Price's work:
> 
> https://lore.kernel.org/linux-mm/[e-mail]/
> 
> Perhaps the two of you can collaborate on a patch series?

Will check this patch.

> 
>>   	u |= kpf_copy_bit(k, KPF_SLAB,		PG_slab);
>> -	if (PageTail(page) && PageSlab(page))
>> +	if (PageTail(page) && folio_test_slab(folio))
>>   		u |= 1 << KPF_SLAB;
> 
> This doesn't make sense ...
> 

Yes, after commit dcb351cd095a ("page-flags: define behavior SL*B-
related flags on compound pages"), the slab could not be a tail,
I will drop this line.

Patch

diff --git a/fs/proc/page.c b/fs/proc/page.c
index 195b077c0fac..94ab0ba13b16 100644
--- a/fs/proc/page.c
+++ b/fs/proc/page.c
@@ -109,6 +109,7 @@  static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit)
 
 u64 stable_page_flags(struct page *page)
 {
+	struct folio *folio;
 	u64 k;
 	u64 u;
 
@@ -119,6 +120,7 @@  u64 stable_page_flags(struct page *page)
 	if (!page)
 		return 1 << KPF_NOPAGE;
 
+	folio = page_folio(page);
 	k = page->flags;
 	u = 0;
 
@@ -128,11 +130,11 @@  u64 stable_page_flags(struct page *page)
 	 * Note that page->_mapcount is overloaded in SLAB, so the
 	 * simple test in page_mapped() is not enough.
 	 */
-	if (!PageSlab(page) && page_mapped(page))
+	if (!folio_test_slab(folio) && folio_mapped(folio))
 		u |= 1 << KPF_MMAP;
-	if (PageAnon(page))
+	if (folio_test_anon(folio))
 		u |= 1 << KPF_ANON;
-	if (PageKsm(page))
+	if (folio_test_ksm(folio))
 		u |= 1 << KPF_KSM;
 
 	/*
@@ -152,11 +154,9 @@  u64 stable_page_flags(struct page *page)
 	 * to make sure a given page is a thp, not a non-huge compound page.
 	 */
 	else if (PageTransCompound(page)) {
-		struct page *head = compound_head(page);
-
-		if (PageLRU(head) || PageAnon(head))
+		if (folio_test_lru(folio) || folio_test_anon(folio))
 			u |= 1 << KPF_THP;
-		else if (is_huge_zero_page(head)) {
+		else if (is_huge_zero_page(&folio->page)) {
 			u |= 1 << KPF_ZERO_PAGE;
 			u |= 1 << KPF_THP;
 		}
@@ -170,7 +170,7 @@  u64 stable_page_flags(struct page *page)
 	 */
 	if (PageBuddy(page))
 		u |= 1 << KPF_BUDDY;
-	else if (page_count(page) == 0 && is_free_buddy_page(page))
+	else if (folio_ref_count(folio) == 0 && is_free_buddy_page(page))
 		u |= 1 << KPF_BUDDY;
 
 	if (PageOffline(page))
@@ -178,13 +178,13 @@  u64 stable_page_flags(struct page *page)
 	if (PageTable(page))
 		u |= 1 << KPF_PGTABLE;
 
-	if (page_is_idle(page))
+	if (folio_test_idle(folio))
 		u |= 1 << KPF_IDLE;
 
 	u |= kpf_copy_bit(k, KPF_LOCKED,	PG_locked);
 
 	u |= kpf_copy_bit(k, KPF_SLAB,		PG_slab);
-	if (PageTail(page) && PageSlab(page))
+	if (PageTail(page) && folio_test_slab(folio))
 		u |= 1 << KPF_SLAB;
 
 	u |= kpf_copy_bit(k, KPF_ERROR,		PG_error);
@@ -197,7 +197,7 @@  u64 stable_page_flags(struct page *page)
 	u |= kpf_copy_bit(k, KPF_ACTIVE,	PG_active);
 	u |= kpf_copy_bit(k, KPF_RECLAIM,	PG_reclaim);
 
-	if (PageSwapCache(page))
+	if (folio_test_swapcache(folio))
 		u |= 1 << KPF_SWAPCACHE;
 	u |= kpf_copy_bit(k, KPF_SWAPBACKED,	PG_swapbacked);