From c82be0be957631b7eaa4b84ba458e1826484e60d Mon Sep 17 00:00:00 2001
From: "Mike Rapoport (Microsoft)" <rppt@kernel.org>
Date: Wed, 23 Oct 2024 19:27:05 +0300
Subject: [PATCH] mm: vmalloc: don't account for number of nodes for HUGE_VMAP
 allocations

vmalloc allocations with VM_ALLOW_HUGE_VMAP that do not explicitly specify
node ID will use huge pages only if size_per_node is larger than a huge
page.

Still the actual allocated memory is not distributed between nodes and
there is no advantage in such approach.  On the contrary, BPF allocates
SZ_2M * num_possible_nodes() for each new bpf_prog_pack, while it could do
with a single huge page per pack.

Don't account for number of nodes for VM_ALLOW_HUGE_VMAP with NUMA_NO_NODE
and use huge pages whenever the requested allocation size is larger than a
huge page.

Link: https://lkml.kernel.org/r/20241023162711.2579610-3-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Tested-by: kdevops <kdevops@lists.linux.dev>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Song Liu <song@kernel.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 mm/vmalloc.c | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 5480b77f4167..5c0ea4e2b17d 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -3779,8 +3779,6 @@ void *__vmalloc_node_range_noprof(unsigned long size, unsigned long align,
 	}
 
 	if (vmap_allow_huge && (vm_flags & VM_ALLOW_HUGE_VMAP)) {
-		unsigned long size_per_node;
-
 		/*
 		 * Try huge pages. Only try for PAGE_KERNEL allocations,
 		 * others like modules don't yet expect huge pages in
@@ -3788,13 +3786,10 @@ void *__vmalloc_node_range_noprof(unsigned long size, unsigned long align,
 		 * supporting them.
 		 */
 
-		size_per_node = size;
-		if (node == NUMA_NO_NODE)
-			size_per_node /= num_online_nodes();
-		if (arch_vmap_pmd_supported(prot) && size_per_node >= PMD_SIZE)
+		if (arch_vmap_pmd_supported(prot) && size >= PMD_SIZE)
 			shift = PMD_SHIFT;
 		else
-			shift = arch_vmap_pte_supported_shift(size_per_node);
+			shift = arch_vmap_pte_supported_shift(size);
 
 		align = max(real_align, 1UL << shift);
 		size = ALIGN(real_size, 1UL << shift);