From patchwork Fri Oct 21 19:18:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Kosina X-Patchwork-Id: 13015331 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7BAAEC38A2D for ; Fri, 21 Oct 2022 19:18:20 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E71528E0002; Fri, 21 Oct 2022 15:18:19 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E20C18E0001; Fri, 21 Oct 2022 15:18:19 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CE8E48E0002; Fri, 21 Oct 2022 15:18:19 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id BE8E18E0001 for ; Fri, 21 Oct 2022 15:18:19 -0400 (EDT) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 91C80C05A3 for ; Fri, 21 Oct 2022 19:18:19 +0000 (UTC) X-FDA: 80045917518.05.93897EC Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf10.hostedemail.com (Postfix) with ESMTP id 04F6AC002E for ; Fri, 21 Oct 2022 19:18:18 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 83093B82C9E; Fri, 21 Oct 2022 19:18:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 41B2AC433C1; Fri, 21 Oct 2022 19:18:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1666379896; bh=xcqENazRXOMVneuXkFAVRd801+EYKORC9ozJY5P/l00=; h=Date:From:To:cc:Subject:In-Reply-To:References:From; b=hb5eiRLNjKuUaO6iBj0Y0RB7IOmLrHl6KGd+2Kt8lAS0L25sb5Syv7vOhr07S59EZ xeRtBPQsEcHO9dDnS1/Hh8quDOb7POCnutYeKe5RZThBBtyYhKsbs38wraKO7orvUX iC72PaqjLAgIPl6719e0ngu3EQLvZnO4bjZR9koD6Yun4TkMRgvkn7f1l1E4yihiPd +QFlgPLulvLl+CXjN8J5B/MeW5hJETqkDgfwSUv7ehjeGKoTwOpiy99gUK8765Ky3v WyeZNVn5rtDvbh1jfeFPp4n0ew0MKjtrZYuhUKimelPG93cw9pH6HsKPDxUmRIN1X0 rIJMsN6lDhlZQ== Date: Fri, 21 Oct 2022 21:18:12 +0200 (CEST) From: Jiri Kosina To: Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com> cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v3] mm/slab: Annotate kmem_cache_node->list_lock as raw In-Reply-To: Message-ID: References: User-Agent: Alpine 2.21 (LSU 202 2017-01-01) MIME-Version: 1.0 ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=hb5eiRLN; spf=pass (imf10.hostedemail.com: domain of jikos@kernel.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=jikos@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1666379899; a=rsa-sha256; cv=none; b=yjYOR7c2gkqaIweHlWxcZ399niwUMc2LYTmqHA7WzFMu/h4UCLPeftq/tRYc7WDMsE3eQ3 e3EcGVioNAlZdSnfwwOTEl14NBSw3UwOIguhLQOOOak8yKCFFc992RNuaiheFYlbR4lqj5 BrMBjxYhfOanf3up2+Q35xb7WKDnz4c= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1666379899; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=546m5BD6zDkfRR19YvqPXKhx78j/L3mA1Q63VJf/G6c=; b=n/uQ9ZdrRpJZYIoUJ3UCpHeE7Msv+UAuZ9UXYsuo7gzyCW+mEsv8usVRmMjU+p5sPcmPfb Gdj52CMnZG72+KV2tVC4wsyKPzV5ovTUhMhleLnXfc5oM4jIQWZ9QU0BxUsuUDJnYZp+uv vidQgT3kLEdk+cV/1pkxTgeLBmFOLgM= Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=hb5eiRLN; spf=pass (imf10.hostedemail.com: domain of jikos@kernel.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=jikos@kernel.org; dmarc=pass (policy=none) header.from=kernel.org X-Stat-Signature: 4xhgifn6xob61oqyixbba55ggzukxieh X-Rspamd-Queue-Id: 04F6AC002E X-Rspamd-Server: rspam02 X-Rspam-User: X-HE-Tag: 1666379898-899313 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Jiri Kosina The list_lock can be taken in hardirq context when do_drain() is being called via IPI on all cores, and therefore lockdep complains about it, because it can't be preempted on PREEMPT_RT. That's not a real issue, as SLAB can't be built on PREEMPT_RT anyway, but we still want to get rid of the warning on non-PREEMPT_RT builds. Annotate it therefore as a raw lock in order to get rid of he lockdep warning below. ============================= [ BUG: Invalid wait context ] 6.1.0-rc1-00134-ge35184f32151 #4 Not tainted ----------------------------- swapper/3/0 is trying to lock: ffff8bc88086dc18 (&parent->list_lock){..-.}-{3:3}, at: do_drain+0x57/0xb0 other info that might help us debug this: context-{2:2} no locks held by swapper/3/0. stack backtrace: CPU: 3 PID: 0 Comm: swapper/3 Not tainted 6.1.0-rc1-00134-ge35184f32151 #4 Hardware name: LENOVO 20K5S22R00/20K5S22R00, BIOS R0IET38W (1.16 ) 05/31/2017 Call Trace: dump_stack_lvl+0x6b/0x9d __lock_acquire+0x1519/0x1730 ? build_sched_domains+0x4bd/0x1590 ? __lock_acquire+0xad2/0x1730 lock_acquire+0x294/0x340 ? do_drain+0x57/0xb0 ? sched_clock_tick+0x41/0x60 _raw_spin_lock+0x2c/0x40 ? do_drain+0x57/0xb0 do_drain+0x57/0xb0 __flush_smp_call_function_queue+0x138/0x220 __sysvec_call_function+0x4f/0x210 sysvec_call_function+0x4b/0x90 asm_sysvec_call_function+0x16/0x20 RIP: 0010:mwait_idle+0x5e/0x80 Code: 31 d2 65 48 8b 04 25 80 ed 01 00 48 89 d1 0f 01 c8 48 8b 00 a8 08 75 14 66 90 0f 00 2d 0b 78 46 00 31 c0 48 89 c1 fb 0f 01 c9 06 fb 0f 1f 44 00 00 65 48 8b 04 25 80 ed 01 00 f0 80 60 02 df RSP: 0000:ffffa90940217ee0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9bb9f93a RBP: 0000000000000003 R08: 0000000000000001 R09: 0000000000000001 R10: ffffa90940217ea8 R11: 0000000000000000 R12: ffffffffffffffff R13: 0000000000000000 R14: ffff8bc88127c500 R15: 0000000000000000 ? default_idle_call+0x1a/0xa0 default_idle_call+0x4b/0xa0 do_idle+0x1f1/0x2c0 ? _raw_spin_unlock_irqrestore+0x56/0x70 cpu_startup_entry+0x19/0x20 start_secondary+0x122/0x150 secondary_startup_64_no_verify+0xce/0xdb Signed-off-by: Jiri Kosina Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> --- v1->v2: fix !SLAB build failures due to list_lock mismatch v2->v3: really fix it by sending refreshed version of the patch (facepalm) mm/slab.c | 90 +++++++++++++++++++++++++++---------------------------- mm/slab.h | 4 +++ 2 files changed, 49 insertions(+), 45 deletions(-) diff --git a/mm/slab.c b/mm/slab.c index 59c8e28f7b6a..d8a287900193 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -234,7 +234,7 @@ static void kmem_cache_node_init(struct kmem_cache_node *parent) parent->shared = NULL; parent->alien = NULL; parent->colour_next = 0; - spin_lock_init(&parent->list_lock); + raw_spin_lock_init(&parent->list_lock); parent->free_objects = 0; parent->free_touched = 0; } @@ -559,9 +559,9 @@ static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep, slab_node = slab_nid(slab); n = get_node(cachep, slab_node); - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); free_block(cachep, &objp, 1, slab_node, &list); - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); slabs_destroy(cachep, &list); } @@ -684,7 +684,7 @@ static void __drain_alien_cache(struct kmem_cache *cachep, struct kmem_cache_node *n = get_node(cachep, node); if (ac->avail) { - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); /* * Stuff objects into the remote nodes shared array first. * That way we could avoid the overhead of putting the objects @@ -695,7 +695,7 @@ static void __drain_alien_cache(struct kmem_cache *cachep, free_block(cachep, ac->entry, ac->avail, node, list); ac->avail = 0; - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); } } @@ -768,9 +768,9 @@ static int __cache_free_alien(struct kmem_cache *cachep, void *objp, slabs_destroy(cachep, &list); } else { n = get_node(cachep, slab_node); - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); free_block(cachep, &objp, 1, slab_node, &list); - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); slabs_destroy(cachep, &list); } return 1; @@ -811,10 +811,10 @@ static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp) */ n = get_node(cachep, node); if (n) { - spin_lock_irq(&n->list_lock); + raw_spin_lock_irq(&n->list_lock); n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount + cachep->num; - spin_unlock_irq(&n->list_lock); + raw_spin_unlock_irq(&n->list_lock); return 0; } @@ -893,7 +893,7 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep, goto fail; n = get_node(cachep, node); - spin_lock_irq(&n->list_lock); + raw_spin_lock_irq(&n->list_lock); if (n->shared && force_change) { free_block(cachep, n->shared->entry, n->shared->avail, node, &list); @@ -911,7 +911,7 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep, new_alien = NULL; } - spin_unlock_irq(&n->list_lock); + raw_spin_unlock_irq(&n->list_lock); slabs_destroy(cachep, &list); /* @@ -950,7 +950,7 @@ static void cpuup_canceled(long cpu) if (!n) continue; - spin_lock_irq(&n->list_lock); + raw_spin_lock_irq(&n->list_lock); /* Free limit for this kmem_cache_node */ n->free_limit -= cachep->batchcount; @@ -961,7 +961,7 @@ static void cpuup_canceled(long cpu) nc->avail = 0; if (!cpumask_empty(mask)) { - spin_unlock_irq(&n->list_lock); + raw_spin_unlock_irq(&n->list_lock); goto free_slab; } @@ -975,7 +975,7 @@ static void cpuup_canceled(long cpu) alien = n->alien; n->alien = NULL; - spin_unlock_irq(&n->list_lock); + raw_spin_unlock_irq(&n->list_lock); kfree(shared); if (alien) { @@ -1159,7 +1159,7 @@ static void __init init_list(struct kmem_cache *cachep, struct kmem_cache_node * /* * Do not assume that spinlocks can be initialized via memcpy: */ - spin_lock_init(&ptr->list_lock); + raw_spin_lock_init(&ptr->list_lock); MAKE_ALL_LISTS(cachep, ptr, nodeid); cachep->node[nodeid] = ptr; @@ -1330,11 +1330,11 @@ slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid) for_each_kmem_cache_node(cachep, node, n) { unsigned long total_slabs, free_slabs, free_objs; - spin_lock_irqsave(&n->list_lock, flags); + raw_spin_lock_irqsave(&n->list_lock, flags); total_slabs = n->total_slabs; free_slabs = n->free_slabs; free_objs = n->free_objects; - spin_unlock_irqrestore(&n->list_lock, flags); + raw_spin_unlock_irqrestore(&n->list_lock, flags); pr_warn(" node %d: slabs: %ld/%ld, objs: %ld/%ld\n", node, total_slabs - free_slabs, total_slabs, @@ -2096,7 +2096,7 @@ static void check_spinlock_acquired(struct kmem_cache *cachep) { #ifdef CONFIG_SMP check_irq_off(); - assert_spin_locked(&get_node(cachep, numa_mem_id())->list_lock); + assert_raw_spin_locked(&get_node(cachep, numa_mem_id())->list_lock); #endif } @@ -2104,7 +2104,7 @@ static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node) { #ifdef CONFIG_SMP check_irq_off(); - assert_spin_locked(&get_node(cachep, node)->list_lock); + assert_raw_spin_locked(&get_node(cachep, node)->list_lock); #endif } @@ -2144,9 +2144,9 @@ static void do_drain(void *arg) check_irq_off(); ac = cpu_cache_get(cachep); n = get_node(cachep, node); - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); free_block(cachep, ac->entry, ac->avail, node, &list); - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); ac->avail = 0; slabs_destroy(cachep, &list); } @@ -2164,9 +2164,9 @@ static void drain_cpu_caches(struct kmem_cache *cachep) drain_alien_cache(cachep, n->alien); for_each_kmem_cache_node(cachep, node, n) { - spin_lock_irq(&n->list_lock); + raw_spin_lock_irq(&n->list_lock); drain_array_locked(cachep, n->shared, node, true, &list); - spin_unlock_irq(&n->list_lock); + raw_spin_unlock_irq(&n->list_lock); slabs_destroy(cachep, &list); } @@ -2188,10 +2188,10 @@ static int drain_freelist(struct kmem_cache *cache, nr_freed = 0; while (nr_freed < tofree && !list_empty(&n->slabs_free)) { - spin_lock_irq(&n->list_lock); + raw_spin_lock_irq(&n->list_lock); p = n->slabs_free.prev; if (p == &n->slabs_free) { - spin_unlock_irq(&n->list_lock); + raw_spin_unlock_irq(&n->list_lock); goto out; } @@ -2204,7 +2204,7 @@ static int drain_freelist(struct kmem_cache *cache, * to the cache. */ n->free_objects -= cache->num; - spin_unlock_irq(&n->list_lock); + raw_spin_unlock_irq(&n->list_lock); slab_destroy(cache, slab); nr_freed++; } @@ -2629,7 +2629,7 @@ static void cache_grow_end(struct kmem_cache *cachep, struct slab *slab) INIT_LIST_HEAD(&slab->slab_list); n = get_node(cachep, slab_nid(slab)); - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); n->total_slabs++; if (!slab->active) { list_add_tail(&slab->slab_list, &n->slabs_free); @@ -2639,7 +2639,7 @@ static void cache_grow_end(struct kmem_cache *cachep, struct slab *slab) STATS_INC_GROWN(cachep); n->free_objects += cachep->num - slab->active; - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); fixup_objfreelist_debug(cachep, &list); } @@ -2805,7 +2805,7 @@ static struct slab *get_first_slab(struct kmem_cache_node *n, bool pfmemalloc) { struct slab *slab; - assert_spin_locked(&n->list_lock); + assert_raw_spin_locked(&n->list_lock); slab = list_first_entry_or_null(&n->slabs_partial, struct slab, slab_list); if (!slab) { @@ -2832,10 +2832,10 @@ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep, if (!gfp_pfmemalloc_allowed(flags)) return NULL; - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); slab = get_first_slab(n, true); if (!slab) { - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); return NULL; } @@ -2844,7 +2844,7 @@ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep, fixup_slab_list(cachep, n, slab, &list); - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); fixup_objfreelist_debug(cachep, &list); return obj; @@ -2903,7 +2903,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags) if (!n->free_objects && (!shared || !shared->avail)) goto direct_grow; - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); shared = READ_ONCE(n->shared); /* See if we can refill from the shared array */ @@ -2927,7 +2927,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags) must_grow: n->free_objects -= ac->avail; alloc_done: - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); fixup_objfreelist_debug(cachep, &list); direct_grow: @@ -3147,7 +3147,7 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, BUG_ON(!n); check_irq_off(); - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); slab = get_first_slab(n, false); if (!slab) goto must_grow; @@ -3165,12 +3165,12 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, fixup_slab_list(cachep, n, slab, &list); - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); fixup_objfreelist_debug(cachep, &list); return obj; must_grow: - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); slab = cache_grow_begin(cachep, gfp_exact_node(flags), nodeid); if (slab) { /* This slab isn't counted yet so don't update free_objects */ @@ -3325,7 +3325,7 @@ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) check_irq_off(); n = get_node(cachep, node); - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); if (n->shared) { struct array_cache *shared_array = n->shared; int max = shared_array->limit - shared_array->avail; @@ -3354,7 +3354,7 @@ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) STATS_SET_FREEABLE(cachep, i); } #endif - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); ac->avail -= batchcount; memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail); slabs_destroy(cachep, &list); @@ -3721,9 +3721,9 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit, node = cpu_to_mem(cpu); n = get_node(cachep, node); - spin_lock_irq(&n->list_lock); + raw_spin_lock_irq(&n->list_lock); free_block(cachep, ac->entry, ac->avail, node, &list); - spin_unlock_irq(&n->list_lock); + raw_spin_unlock_irq(&n->list_lock); slabs_destroy(cachep, &list); } free_percpu(prev); @@ -3815,9 +3815,9 @@ static void drain_array(struct kmem_cache *cachep, struct kmem_cache_node *n, return; } - spin_lock_irq(&n->list_lock); + raw_spin_lock_irq(&n->list_lock); drain_array_locked(cachep, ac, node, false, &list); - spin_unlock_irq(&n->list_lock); + raw_spin_unlock_irq(&n->list_lock); slabs_destroy(cachep, &list); } @@ -3901,7 +3901,7 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo) for_each_kmem_cache_node(cachep, node, n) { check_irq_on(); - spin_lock_irq(&n->list_lock); + raw_spin_lock_irq(&n->list_lock); total_slabs += n->total_slabs; free_slabs += n->free_slabs; @@ -3910,7 +3910,7 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo) if (n->shared) shared_avail += n->shared->avail; - spin_unlock_irq(&n->list_lock); + raw_spin_unlock_irq(&n->list_lock); } num_objs = total_slabs * cachep->num; active_slabs = total_slabs - free_slabs; diff --git a/mm/slab.h b/mm/slab.h index 0202a8c2f0d2..7a705e4228c8 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -750,7 +750,11 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, * The slab lists for all objects. */ struct kmem_cache_node { +#ifdef CONFIG_SLAB + raw_spinlock_t list_lock; +#else spinlock_t list_lock; +#endif #ifdef CONFIG_SLAB struct list_head slabs_partial; /* partial list first, better asm code */