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author | Huang Shijie <shijie@os.amperecomputing.com> | 2024-01-26 09:44:51 +0300 |
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committer | Andrew Morton <akpm@linux-foundation.org> | 2024-04-26 07:07:03 +0300 |
commit | f9899c028151468d8c4af0bcbb3d5e87619b0973 (patch) | |
tree | 7cbea05d8d8125b809fe324457339e013e80baf0 | |
parent | 4d9784c00a15631b68a5d95be907aa308f269551 (diff) | |
download | linux-f9899c028151468d8c4af0bcbb3d5e87619b0973.tar.xz |
NUMA: early use of cpu_to_node() returns 0 instead of the correct node id
During the kernel booting, the generic cpu_to_node() is called too early
in arm64, powerpc and riscv when CONFIG_NUMA is enabled.
There are at least four places in the common code where
the generic cpu_to_node() is called before it is initialized:
1.) early_trace_init() in kernel/trace/trace.c
2.) sched_init() in kernel/sched/core.c
3.) init_sched_fair_class() in kernel/sched/fair.c
4.) workqueue_init_early() in kernel/workqueue.c
This will harm performance since there is an increase in off node
accesses.
In order to fix the bug, the patch introduces early_numa_node_init() which
is called after smp_prepare_boot_cpu() in start_kernel.
early_numa_node_init will initialize the "numa_node" as soon as the
early_cpu_to_node() is ready, before the cpu_to_node() is called at the
first time.
Link: https://lkml.kernel.org/r/20240126064451.5465-1-shijie@os.amperecomputing.com
Signed-off-by: Huang Shijie <shijie@os.amperecomputing.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com> [RISC-V]
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Kelley (LINUX) <mikelley@microsoft.com>
Cc: "Mike Rapoport (IBM)" <rppt@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
-rw-r--r-- | init/main.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/init/main.c b/init/main.c index 6b4b656cef1d..0aecd2839c1f 100644 --- a/init/main.c +++ b/init/main.c @@ -882,6 +882,19 @@ static void __init print_unknown_bootoptions(void) memblock_free(unknown_options, len); } +static void __init early_numa_node_init(void) +{ +#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID +#ifndef cpu_to_node + int cpu; + + /* The early_cpu_to_node() should be ready here. */ + for_each_possible_cpu(cpu) + set_cpu_numa_node(cpu, early_cpu_to_node(cpu)); +#endif +#endif +} + asmlinkage __visible __init __no_sanitize_address __noreturn __no_stack_protector void start_kernel(void) { @@ -912,6 +925,7 @@ void start_kernel(void) setup_nr_cpu_ids(); setup_per_cpu_areas(); smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ + early_numa_node_init(); boot_cpu_hotplug_init(); pr_notice("Kernel command line: %s\n", saved_command_line); |