+ __mod_memcg_lruvec_state-enhance-diagnostics.patch added to mm-unstable branch

+ __mod_memcg_lruvec_state-enhance-diagnostics.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: __mod_memcg_lruvec_state(): enhance diagnostics
has been added to the -mm mm-unstable branch.  Its filename is
     __mod_memcg_lruvec_state-enhance-diagnostics.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/__mod_memcg_lruvec_state-enhance-diagnostics.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

------------------------------------------------------
From: Andrew Morton <akpm@linux-foundation.org>
Subject: __mod_memcg_lruvec_state(): enhance diagnostics
Date: Wed Apr  3 05:42:47 PM PDT 2024

sysbot reports a warning
(https://lkml.kernel.org/r/0000000000007545d00615188a03@google.com).  Add
additional info to perhaps help with this.



Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/mm/memcontrol.c~__mod_memcg_lruvec_state-enhance-diagnostics
+++ a/mm/memcontrol.c
@@ -860,10 +860,12 @@ void __mod_memcg_lruvec_state(struct lru
 		case NR_ANON_THPS:
 		case NR_SHMEM_PMDMAPPED:
 		case NR_FILE_PMDMAPPED:
-			WARN_ON_ONCE(!in_task());
+			if (WARN_ON_ONCE(!in_task()))
+				pr_warn("stat item index: %d\n", idx);
 			break;
 		default:
-			VM_WARN_ON_IRQS_ENABLED();
+			if (VM_WARN_ON_IRQS_ENABLED())
+				pr_warn("stat item index: %d\n", idx);
 		}
 	}
 
_

Patches currently in -mm which might be from akpm@linux-foundation.org are

mm-sparc-change-pxd_huge-behavior-to-exclude-swap-entries-fix.patch
mm-hold-ptl-from-the-first-pte-while-reclaiming-a-large-folio-fix.patch
sh-remove-use-of-pg_arch_1-on-individual-pages-fix.patch
mm-gup-drop-folio_fast_pin_allowed-in-hugepd-processing-fix.patch
__mod_memcg_lruvec_state-enhance-diagnostics.patch