From patchwork Tue Feb 20 09:05:21 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Huang, Rulin" X-Patchwork-Id: 13563676 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 24426C48BC4 for ; Tue, 20 Feb 2024 09:02:45 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id AF3EA6B0082; Tue, 20 Feb 2024 04:02:44 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id AA4276B0083; Tue, 20 Feb 2024 04:02:44 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 96C976B0085; Tue, 20 Feb 2024 04:02:44 -0500 (EST) 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 87B4C6B0082 for ; Tue, 20 Feb 2024 04:02:44 -0500 (EST) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 527041C0401 for ; Tue, 20 Feb 2024 09:02:44 +0000 (UTC) X-FDA: 81811591848.01.1BDB61D Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.18]) by imf10.hostedemail.com (Postfix) with ESMTP id BD8ABC0005 for ; Tue, 20 Feb 2024 09:02:41 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=D17uZO74; spf=pass (imf10.hostedemail.com: domain of rulin.huang@intel.com designates 192.198.163.18 as permitted sender) smtp.mailfrom=rulin.huang@intel.com; dmarc=pass (policy=none) header.from=intel.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1708419762; 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-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=JV7XRgkyn32uFBYga8rvYebRxax991AzZuQhaMoyqkk=; b=i7ciCDi2Uedi67PrwSCWlnU7Qr0if7zaN1XZ2XRN/Awm6kUUA/LlbNc88zRPqLp9toH88B xeBjndBwUu9BjtX7BFnbjcH2maEEQqOSZK++EwYfHO/L8OqHRP6OD1wY3ZZ7j42K6m9Nvb 1G4rwojJ7FmiGve2B8ncqmN+sgvWBrQ= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=D17uZO74; spf=pass (imf10.hostedemail.com: domain of rulin.huang@intel.com designates 192.198.163.18 as permitted sender) smtp.mailfrom=rulin.huang@intel.com; dmarc=pass (policy=none) header.from=intel.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1708419762; a=rsa-sha256; cv=none; b=YI557hG7ouMKQ0lFABNp6X35lHIy2ICaiygnJbO4oOiNtphvCu0SU+nH7x1qqokDze2y7s 1dlRxZLM60p4ibNPICSLWwXUkzR+/ciEOsM5gd3184o1xXrSpCFnPS+FZEWwAemm46T0wk XIFx05y2IKF6G5+INF9L/p5qN27qCM4= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1708419762; x=1739955762; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=mYhlp/eMEhKS03KF61dRGQDnPpkxK3pDWAEVI1m8zMM=; b=D17uZO74VXZeP4E2svMs6mghz4zLLb4+zZAxNCCDqRbGmUFYuFuZADls FzQkCkVHyt8zcdj0iiHreuoOJWesjmySr4yCHRMie/L0AkQS90yZY+f10 uPaPgY0KBv+FEzIisgJRftogcuTd2H0pVJ/T7gzXk5LqnelItm4lXLh0l pbVNneQ/hUXqr68lkRr5e4Qfq3RGk+ZJEGFIt8Ca3Yfp4AthfxpA6JWQy 54rcjpXPe85szAeW5sNsXRU+lCmW6MpCw8eaGQ0B9TQzjT6Pj8qsENGWD FlhKGbmL4Z4JUWGhlZHRlwuwPS456m4ueRiRJ6o8hnglBCKeXMrAEn6sJ g==; X-IronPort-AV: E=McAfee;i="6600,9927,10989"; a="2391933" X-IronPort-AV: E=Sophos;i="6.06,172,1705392000"; d="scan'208";a="2391933" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmvoesa112.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Feb 2024 01:02:31 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10989"; a="913039557" X-IronPort-AV: E=Sophos;i="6.06,172,1705392000"; d="scan'208";a="913039557" Received: from linux-pnp-server-09.sh.intel.com ([10.239.176.190]) by fmsmga002.fm.intel.com with ESMTP; 20 Feb 2024 01:02:27 -0800 From: rulinhuang To: urezki@gmail.com Cc: akpm@linux-foundation.org, colin.king@intel.com, hch@infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, lstoakes@gmail.com, rulin.huang@intel.com, tim.c.chen@intel.com, zhiguo.zhou@intel.com, wangyang.guo@intel.com, tianyou.li@intel.com Subject: [PATCH v2] mm/vmalloc: lock contention optimization under multi-threading Date: Tue, 20 Feb 2024 04:05:21 -0500 Message-ID: <20240220090521.3316345-1-rulin.huang@intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240209115147.261510-1-rulin.huang@intel.com> References: <20240209115147.261510-1-rulin.huang@intel.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: BD8ABC0005 X-Rspam-User: X-Stat-Signature: sd6nba6iqadzsd18ck9jnq4u5spmpsfs X-Rspamd-Server: rspam01 X-HE-Tag: 1708419761-297554 X-HE-Meta: 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 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: List-Subscribe: List-Unsubscribe: When allocating a new memory area where the mapping address range is known, it is observed that the vmap_area lock is acquired twice. The first acquisition occurs in the alloc_vmap_area() function when inserting the vm area into the vm mapping red-black tree. The second acquisition occurs in the setup_vmalloc_vm() function when updating the properties of the vm, such as flags and address, etc. Combine these two operations together in alloc_vmap_area(), which improves scalability when the vmap_area lock is contended. By doing so, the need to acquire the lock twice can also be eliminated. With the above change, tested on intel icelake platform(160 vcpu, kernel v6.7), a 6% performance improvement and a 7% reduction in overall spinlock hotspot are gained on stress-ng/pthread(https://github.com/ColinIanKing/stress-ng), which is the stress test of thread creations. Reviewed-by: Chen Tim C Reviewed-by: King Colin Signed-off-by: rulinhuang --- V1 -> V2: Avoided the partial initialization issue of vm and separated insert_vmap_area() from alloc_vmap_area() --- mm/vmalloc.c | 36 +++++++++++++++++++++--------------- 1 file changed, 21 insertions(+), 15 deletions(-) base-commit: de927f6c0b07d9e698416c5b287c521b07694cac diff --git a/mm/vmalloc.c b/mm/vmalloc.c index d12a17fc0c171..768e45f2ed946 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1630,17 +1630,18 @@ static struct vmap_area *alloc_vmap_area(unsigned long size, va->vm = NULL; va->flags = va_flags; - spin_lock(&vmap_area_lock); - insert_vmap_area(va, &vmap_area_root, &vmap_area_list); - spin_unlock(&vmap_area_lock); - BUG_ON(!IS_ALIGNED(va->va_start, align)); BUG_ON(va->va_start < vstart); BUG_ON(va->va_end > vend); ret = kasan_populate_vmalloc(addr, size); if (ret) { - free_vmap_area(va); + /* + * Insert/Merge it back to the free tree/list. + */ + spin_lock(&free_vmap_area_lock); + merge_or_add_vmap_area_augment(va, &free_vmap_area_root, &free_vmap_area_list); + spin_unlock(&free_vmap_area_lock); return ERR_PTR(ret); } @@ -1669,6 +1670,13 @@ static struct vmap_area *alloc_vmap_area(unsigned long size, return ERR_PTR(-EBUSY); } +static inline void insert_vmap_area_with_lock(struct vmap_area *va) +{ + spin_lock(&vmap_area_lock); + insert_vmap_area(va, &vmap_area_root, &vmap_area_list); + spin_unlock(&vmap_area_lock); +} + int register_vmap_purge_notifier(struct notifier_block *nb) { return blocking_notifier_chain_register(&vmap_notify_list, nb); @@ -2045,6 +2053,8 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask) return ERR_CAST(va); } + insert_vmap_area_with_lock(va); + vaddr = vmap_block_vaddr(va->va_start, 0); spin_lock_init(&vb->lock); vb->va = va; @@ -2398,6 +2408,8 @@ void *vm_map_ram(struct page **pages, unsigned int count, int node) if (IS_ERR(va)) return NULL; + insert_vmap_area_with_lock(va); + addr = va->va_start; mem = (void *)addr; } @@ -2538,7 +2550,7 @@ static void vmap_init_free_space(void) } } -static inline void setup_vmalloc_vm_locked(struct vm_struct *vm, +static inline void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va, unsigned long flags, const void *caller) { vm->flags = flags; @@ -2548,14 +2560,6 @@ static inline void setup_vmalloc_vm_locked(struct vm_struct *vm, va->vm = vm; } -static void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va, - unsigned long flags, const void *caller) -{ - spin_lock(&vmap_area_lock); - setup_vmalloc_vm_locked(vm, va, flags, caller); - spin_unlock(&vmap_area_lock); -} - static void clear_vm_uninitialized_flag(struct vm_struct *vm) { /* @@ -2600,6 +2604,8 @@ static struct vm_struct *__get_vm_area_node(unsigned long size, setup_vmalloc_vm(area, va, flags, caller); + insert_vmap_area_with_lock(va); + /* * Mark pages for non-VM_ALLOC mappings as accessible. Do it now as a * best-effort approach, as they can be mapped outside of vmalloc code. @@ -4166,7 +4172,7 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, for (area = 0; area < nr_vms; area++) { insert_vmap_area(vas[area], &vmap_area_root, &vmap_area_list); - setup_vmalloc_vm_locked(vms[area], vas[area], VM_ALLOC, + setup_vmalloc_vm(vms[area], vas[area], VM_ALLOC, pcpu_get_vm_areas); } spin_unlock(&vmap_area_lock);