+ cgroup-cpuset-update-some-comments-about-the-page-allocator.patch added to mm-new branch

+ cgroup-cpuset-update-some-comments-about-the-page-allocator.patch added to mm-new branch

[Andrew Morton]

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The patch titled
     Subject: cgroup/cpuset: update some comments about the page allocator
has been added to the -mm mm-new branch.  Its filename is
     cgroup-cpuset-update-some-comments-about-the-page-allocator.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/cgroup-cpuset-update-some-comments-about-the-page-allocator.patch

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

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

The mm-new branch of mm.git is not included in linux-next

If a few days of testing in mm-new is successful, the patch will me moved
into mm.git's mm-unstable branch, which is included in linux-next

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------------------------------------------------------
From: Brendan Jackman <jackmanb@google.com>
Subject: cgroup/cpuset: update some comments about the page allocator
Date: Wed, 15 Jul 2026 11:03:19 +0000

These comments describing the page allocator are out of date:

- __alloc_pages() is no longer a public API and has no business being
  described outside of mm/.

- The `wait` variable is gone.

It may be out of date for other reasons too but this patch is just
fixing the issues that stood out.

To fix it:

- Instead of referring to a specific function, instead to "the page
  allocator"

- Completely drop out-of-date details of that function's internal
  behaviour, since they were irrelevant anyway.

Link: https://lore.kernel.org/20260715-spin-trylock-followup-v3-2-fc4d246f705d@google.com
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Suggested-by: Zi Yan <ziy@nvidia.com>
Link: https://lore.kernel.org/all/DJP11T5V7BDW.2FZZZ8R6LOY4I@nvidia.com/
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/cgroup/cpuset.c |   13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

--- a/kernel/cgroup/cpuset.c~cgroup-cpuset-update-some-comments-about-the-page-allocator
+++ a/kernel/cgroup/cpuset.c
@@ -4193,7 +4193,7 @@ static struct cpuset *nearest_hardwall_a
  * nearest enclosing hardwalled ancestor cpuset.
  *
  * Scanning up parent cpusets requires callback_lock.  The
- * __alloc_pages() routine only calls here with __GFP_HARDWALL bit
+ * page allocator only calls here with __GFP_HARDWALL bit
  * _not_ set if it's a GFP_KERNEL allocation, and all nodes in the
  * current tasks mems_allowed came up empty on the first pass over
  * the zonelist.  So only GFP_KERNEL allocations, if all nodes in the
@@ -4206,11 +4206,8 @@ static struct cpuset *nearest_hardwall_a
  * come before the __GFP_HARDWALL check, otherwise a dying task
  * would be blocked on the fast path.
  *
- * The second pass through get_page_from_freelist() doesn't even call
- * here for GFP_ATOMIC calls.  For those calls, the __alloc_pages()
- * variable 'wait' is not set, and the bit ALLOC_CPUSET is not set
- * in alloc_flags.  That logic and the checks below have the combined
- * affect that:
+ * The second pass through get_page_from_freelist() doesn't even call here for
+ * GFP_ATOMIC calls.  That, and the checks below have the combined affect that:
  *	in_interrupt - any node ok (current task context irrelevant)
  *	GFP_ATOMIC   - any node ok
  *	tsk_is_oom_victim   - any node ok
@@ -4327,8 +4324,8 @@ void cpuset_nodes_allowed(struct cgroup
  * should not be possible for the following code to return an
  * offline node.  But if it did, that would be ok, as this routine
  * is not returning the node where the allocation must be, only
- * the node where the search should start.  The zonelist passed to
- * __alloc_pages() will include all nodes.  If the slab allocator
+ * the node where the search should start.  The zonelist used by
+ * the allocator will include all nodes.  If the slab allocator
  * is passed an offline node, it will fall back to the local node.
  * See kmem_cache_alloc_node().
  */
_

Patches currently in -mm which might be from jackmanb@google.com are

mm-page_alloc-drop-flag-conversion-optimisation.patch
mm-secretmem-disable-under-highmem.patch
mm-page_alloc-rename-alloc_trylock-alloc_nolock.patch
mm-page_alloc-some-renames-to-clarify-alloc_flags-scopes.patch
mm-name-some-args-in-a-function-declaration.patch
mm-split-out-internal-page_alloch.patch
mm-page_alloc-unify-__alloc_frozen_pages_noprof.patch
mm-page_alloc-relax-gfp-warn-in-nolock-allocs.patch
mm-move-some-stuff-to-mm-page_alloch.patch
perf-x86-intel-use-higher-level-allocator-api.patch
kvm-vmx-use-higher-level-allocator-api.patch
x86-virt-use-higher-level-allocator-api.patch
sgi-xp-use-higher-level-allocator-api.patch
net-funeth-switch-to-higher-level-allocator-api.patch
mm-remove-__alloc_pages_node.patch
mm-move-__alloc_pages-to-mm-page_alloch.patch
mm-replace-__gfp_no_codetag-with-alloc_no_codetag.patch
mm-page_alloc-drop-alloc_flags-arg-from-alloc_flags_cma.patch
mm-factor-out-can_spin_trylock.patch
mm-page_alloc-rename-fpi_trylock-fpi_nolock.patch
cgroup-cpuset-update-some-comments-about-the-page-allocator.patch
mm-page_alloc-fixup-alloc_pages_nolock_noprof-comment.patch
mm-page_alloc-remove-a-couple-of-vm_bug_onst.patch