github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-07-27 17:47:41 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

mm/sparse: remove unnecessary NULL check before allocating mem_section

Browse Source 
Commit 850ed20539 ("mm: move array mem_section init code out of
memory_present()") moved mem_section allocation logic into
memblocks_present().

Before that move, memory_present() could be called multiple times, so
unlikely() matched the common case, where most calls found mem_section
already allocated.

After that move, memblocks_present() is called exactly once from
sparse_init().  Under CONFIG_SPARSEMEM_EXTREME, mem_section is always NULL
when it is called.

So remove unnecessary NULL check before allocating mem_section.  No
functional change.

Link: https://lore.kernel.org/20260419144225.2875654-1-ekffu200098@gmail.com
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed by: Donet Tom <donettom@linux.ibm.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Liam Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Sang-Heon Jeon 2026-04-19 23:42:25 +09:00 committed by Andrew Morton
parent 13fe573656
commit e0974347f5
1 changed files with 4 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
mm/sparse.c
View File

@ -201,13 +201,11 @@ static void __init memblocks_present(void)
int i, nid;
#ifdef CONFIG_SPARSEMEM_EXTREME
if (unlikely(!mem_section)) {
unsigned long size, align;
unsigned long size, align;
size = sizeof(struct mem_section *) * NR_SECTION_ROOTS;
align = 1 << (INTERNODE_CACHE_SHIFT);
mem_section = memblock_alloc_or_panic(size, align);
}
size = sizeof(struct mem_section *) * NR_SECTION_ROOTS;
align = 1 << (INTERNODE_CACHE_SHIFT);
mem_section = memblock_alloc_or_panic(size, align);
#endif
for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, &nid)