From 9ddf872b47e3ac8f27dbfc4a4737a976c7588de6 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Thu, 4 Jan 2024 08:57:44 -0800 Subject: [PATCH] bpf: Remove unnecessary cpu == 0 check in memalloc After merging the patch set [1] to reduce memory usage for bpf_global_percpu_ma, Alexei found a redundant check (cpu == 0) in function bpf_mem_alloc_percpu_unit_init() ([2]). Indeed, the check is unnecessary since c->unit_size will be all NULL or all non-NULL for all cpus before for_each_possible_cpu() loop. Removing the check makes code less confusing. [1] https://lore.kernel.org/all/20231222031729.1287957-1-yonghong.song@linux.dev/ [2] https://lore.kernel.org/all/20231222031745.1289082-1-yonghong.song@linux.dev/ Signed-off-by: Yonghong Song Link: https://lore.kernel.org/r/20240104165744.702239-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov --- kernel/bpf/memalloc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index 460c8f38fed6..550f02e2cb13 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -613,7 +613,7 @@ int bpf_mem_alloc_percpu_unit_init(struct bpf_mem_alloc *ma, int size) for_each_possible_cpu(cpu) { cc = per_cpu_ptr(pcc, cpu); c = &cc->cache[i]; - if (cpu == 0 && c->unit_size) + if (c->unit_size) break; c->unit_size = unit_size;