+ mm-vmallocc-change-purge_ndoes-as-local-static-variable.patch added to mm-new branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm/vmalloc.c: change purge_ndoes as local static variable
has been added to the -mm mm-new branch.  Its filename is
     mm-vmallocc-change-purge_ndoes-as-local-static-variable.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmallocc-change-purge_ndoes-as-local-static-variable.patch

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

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------------------------------------------------------
From: Baoquan He <bhe@redhat.com>
Subject: mm/vmalloc.c: change purge_ndoes as local static variable
Date: Sat, 19 Apr 2025 06:36:49 +0800

Patch series "mm/vmalloc.c: code cleanup and improvements", v2.

These changes were made from code inspection in mm/vmalloc.c.


This patch (of 5):

Static variable 'purge_ndoes' is defined in global scope, while it's only
used in function __purge_vmap_area_lazy().  It mainly serves to avoid
memory allocation repeatedly, especially when NR_CPUS is big.

While a local static variable can also satisfy the demand, and can improve
code readibility.  Hence move its definition into
__purge_vmap_area_lazy().

Link: https://lkml.kernel.org/r/20250418223653.243436-1-bhe@redhat.com
Link: https://lkml.kernel.org/r/20250418223653.243436-2-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Shivank Garg <shivankg@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmalloc.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/vmalloc.c~mm-vmallocc-change-purge_ndoes-as-local-static-variable
+++ a/mm/vmalloc.c
@@ -2127,7 +2127,6 @@ static DEFINE_MUTEX(vmap_purge_lock);
 
 /* for per-CPU blocks */
 static void purge_fragmented_blocks_allcpus(void);
-static cpumask_t purge_nodes;
 
 static void
 reclaim_list_global(struct list_head *head)
@@ -2260,6 +2259,7 @@ static bool __purge_vmap_area_lazy(unsig
 {
 	unsigned long nr_purged_areas = 0;
 	unsigned int nr_purge_helpers;
+	static cpumask_t purge_nodes;
 	unsigned int nr_purge_nodes;
 	struct vmap_node *vn;
 	int i;
_

Patches currently in -mm which might be from bhe@redhat.com are

mm-gup-remove-unneeded-checking-in-follow_page_pte.patch
mm-gup-remove-gup_fast_pgd_leaf-and-clean-up-the-relevant-codes.patch
mm-gup-clean-up-codes-in-fault_in_xxx-functions.patch
mm-gup-clean-up-codes-in-fault_in_xxx-functions-v5.patch
mm-vmallocc-change-purge_ndoes-as-local-static-variable.patch
mm-vmallocc-find-the-vmap-of-vmap_nodes-in-reverse-order.patch
mm-vmallocc-optimize-code-in-decay_va_pool_node-a-little-bit.patch
mm-vmalloc-optimize-function-vm_unmap_aliases.patch
mm-vmallocc-return-explicit-error-value-in-alloc_vmap_area.patch