From 849fec81830ae466af1fb96597e056e326dae48d Mon Sep 17 00:00:00 2001 From: Vlastimil Babka Date: Mon, 7 Aug 2023 23:00:36 +0200 Subject: [PATCH] maple_tree: replace preallocation with slub percpu array prefill With the percpu array we can try not doing the preallocations in maple tree, and instead make sure the percpu array is prefilled, and using GFP_ATOMIC in places that relied on the preallocation (in case we miss or fail trylock on the array), i.e. mas_store_prealloc(). For now simply add __GFP_NOFAIL there as well. --- lib/maple_tree.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) diff --git a/lib/maple_tree.c b/lib/maple_tree.c index 1591f3917b7e6..b21c53cb085d2 100644 --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -5428,7 +5428,12 @@ void mas_store_prealloc(struct ma_state *mas, void *entry) mas_wr_store_setup(&wr_mas); trace_ma_write(__func__, mas, 0, entry); + +retry: mas_wr_store_entry(&wr_mas); + if (unlikely(mas_nomem(mas, GFP_ATOMIC | __GFP_NOFAIL))) + goto retry; + MAS_WR_BUG_ON(&wr_mas, mas_is_err(mas)); mas_destroy(mas); } @@ -5447,8 +5452,6 @@ int mas_preallocate(struct ma_state *mas, void *entry, gfp_t gfp) MA_WR_STATE(wr_mas, mas, entry); unsigned char node_size; int request = 1; - int ret; - if (unlikely(!mas->index && mas->last == ULONG_MAX)) goto ask_now; @@ -5499,16 +5502,8 @@ int mas_preallocate(struct ma_state *mas, void *entry, gfp_t gfp) /* node store, slot store needs one node */ ask_now: - mas_node_count_gfp(mas, request, gfp); - if (likely(!mas_is_err(mas))) - return 0; + return kmem_cache_prefill_percpu_array(maple_node_cache, request, gfp); - mas_set_alloc_req(mas, 0); - ret = xa_err(mas->node); - mas_reset(mas); - mas_destroy(mas); - mas_reset(mas); - return ret; } EXPORT_SYMBOL_GPL(mas_preallocate); -- 2.50.1