The following commit has been merged into the core/debugobjects branch of tip: Commit-ID: a201a96b9682e5b42ed93108c4aeb6135c909661 Gitweb: https://git.kernel.org/tip/a201a96b9682e5b42ed93108c4aeb6135c909661 Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx> AuthorDate: Mon, 07 Oct 2024 18:50:19 +02:00 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitterDate: Tue, 15 Oct 2024 17:30:33 +02:00 debugobjects: Double the per CPU slots In situations where objects are rapidly allocated from the pool and handed back, the size of the per CPU pool turns out to be too small. Double the size of the per CPU pool. This reduces the kmem cache allocation and free operations during a kernel compile: alloc free Baseline: 380k 330k Double size: 295k 245k Especially the reduction of allocations is important because that happens in the hot path when objects are initialized. The maximum increase in per CPU pool memory consumption is about 2.5K per online CPU, which is acceptable. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Reviewed-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx> Link: https://lore.kernel.org/all/20241007164914.378676302@xxxxxxxxxxxxx --- lib/debugobjects.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/debugobjects.c b/lib/debugobjects.c index cf704e2..fc9397d 100644 --- a/lib/debugobjects.c +++ b/lib/debugobjects.c @@ -28,7 +28,7 @@ #define ODEBUG_POOL_SIZE (64 * ODEBUG_BATCH_SIZE) #define ODEBUG_POOL_MIN_LEVEL (ODEBUG_POOL_SIZE / 4) -#define ODEBUG_POOL_PERCPU_SIZE (4 * ODEBUG_BATCH_SIZE) +#define ODEBUG_POOL_PERCPU_SIZE (8 * ODEBUG_BATCH_SIZE) #define ODEBUG_CHUNK_SHIFT PAGE_SHIFT #define ODEBUG_CHUNK_SIZE (1 << ODEBUG_CHUNK_SHIFT)