From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A34BB58AA6 for ; Thu, 11 Jan 2024 22:21:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="j9kOIsSL" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1705011705; x=1736547705; h=message-id:subject:from:to:cc:date:in-reply-to: references:content-transfer-encoding:mime-version; bh=7YQEppjXt4a37tD2uey9CD8wKb3oJK9JqmRLmduDhrY=; b=j9kOIsSLrOvAkXw6b1DphiBZp7DrF03QjwW06OvHFgoriPGR8ekIo2rs 8Vpfhb+V3F1SHjQVb8P2xnBeuJVJYBYc/WhNXLDVekRjvqW9p9m4FuXx/ IHziR99wLVFUUEvNpUG5wihv/o1bx9XiFE4rMZGstTsHwljVciExx0PWc 930Mr6m6WIJ7dzEkUufRmsOx9zqGkB2lBePQySG/h5mNAVUjFXX95EC7B lt2qQDxvFWucCSuVEV/zVV2k798ceYQbtaMDxVnvyvQufpYyi4HRTNTp1 bonJPLSLfWZMwS6cCFHEqmp0EpNIopxcY/mIiwa/GI0uPbk7AK/z67Ucv A==; X-IronPort-AV: E=McAfee;i="6600,9927,10950"; a="20481191" X-IronPort-AV: E=Sophos;i="6.04,187,1695711600"; d="scan'208";a="20481191" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jan 2024 14:21:44 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10950"; a="1029718749" X-IronPort-AV: E=Sophos;i="6.04,187,1695711600"; d="scan'208";a="1029718749" Received: from ldrake1-mobl3.amr.corp.intel.com (HELO [10.212.168.169]) ([10.212.168.169]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jan 2024 14:21:43 -0800 Message-ID: <66af5bce84c9b6480feaa2ddaff199cd5722fcde.camel@linux.intel.com> Subject: Re: [PATCH v3 4/7] hugetlb: pass *next_nid_to_alloc directly to for_each_node_mask_to_alloc From: Tim Chen To: Gang Li , David Hildenbrand , David Rientjes , Mike Kravetz , Muchun Song , Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, ligang.bdlg@bytedance.com Date: Thu, 11 Jan 2024 14:21:42 -0800 In-Reply-To: <20240102131249.76622-5-gang.li@linux.dev> References: <20240102131249.76622-1-gang.li@linux.dev> <20240102131249.76622-5-gang.li@linux.dev> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.44.4 (3.44.4-2.fc36) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Tue, 2024-01-02 at 21:12 +0800, Gang Li wrote: > The parallelization of hugetlb allocation leads to errors when sharing > h->next_nid_to_alloc across different threads. To address this, it's Suggest you say With parallelization of hugetlb allocation across different threads, each thread works on a differnet node to allocate pages from, instead of all allocating from a common node h->next_nid_to_alloc. To address this= , it's > necessary to assign a separate next_nid_to_alloc for each thread. >=20 > Consequently, the hstate_next_node_to_alloc and for_each_node_mask_to_all= oc > have been modified to directly accept a *next_nid_to_alloc parameter, > ensuring thread-specific allocation and avoiding concurrent access issues= . >=20 > Signed-off-by: Gang Li > --- > This patch seems not elegant, but I can't come up with anything better. > Any suggestions will be highly appreciated! > --- > mm/hugetlb.c | 22 ++++++++++++---------- > 1 file changed, 12 insertions(+), 10 deletions(-) >=20 > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index 92448e747991d..a71bc1622b53b 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -1464,15 +1464,15 @@ static int get_valid_node_allowed(int nid, nodema= sk_t *nodes_allowed) > * next node from which to allocate, handling wrap at end of node > * mask. > */ > -static int hstate_next_node_to_alloc(struct hstate *h, > +static int hstate_next_node_to_alloc(int *next_nid_to_alloc, > nodemask_t *nodes_allowed) > { > int nid; > =20 > VM_BUG_ON(!nodes_allowed); > =20 > - nid =3D get_valid_node_allowed(h->next_nid_to_alloc, nodes_allowed); > - h->next_nid_to_alloc =3D next_node_allowed(nid, nodes_allowed); > + nid =3D get_valid_node_allowed(*next_nid_to_alloc, nodes_allowed); > + *next_nid_to_alloc =3D next_node_allowed(nid, nodes_allowed); > =20 > return nid; > } > @@ -1495,10 +1495,10 @@ static int hstate_next_node_to_free(struct hstate= *h, nodemask_t *nodes_allowed) > return nid; > } > =20 > -#define for_each_node_mask_to_alloc(hs, nr_nodes, node, mask) \ > +#define for_each_node_mask_to_alloc(next_nid_to_alloc, nr_nodes, node, m= ask) \ > for (nr_nodes =3D nodes_weight(*mask); \ > nr_nodes > 0 && \ > - ((node =3D hstate_next_node_to_alloc(hs, mask)) || 1); \ > + ((node =3D hstate_next_node_to_alloc(next_nid_to_alloc, mask)) || 1); = \ > nr_nodes--) > =20 > #define for_each_node_mask_to_free(hs, nr_nodes, node, mask) \ > @@ -2350,12 +2350,13 @@ static void prep_and_add_allocated_folios(struct = hstate *h, > */ > static struct folio *alloc_pool_huge_folio(struct hstate *h, > nodemask_t *nodes_allowed, > - nodemask_t *node_alloc_noretry) > + nodemask_t *node_alloc_noretry, > + int *next_nid_to_alloc) > { > gfp_t gfp_mask =3D htlb_alloc_mask(h) | __GFP_THISNODE; > int nr_nodes, node; > =20 > - for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { > + for_each_node_mask_to_alloc(next_nid_to_alloc, nr_nodes, node, nodes_al= lowed) { > struct folio *folio; > =20 > folio =3D only_alloc_fresh_hugetlb_folio(h, gfp_mask, node, > @@ -3310,7 +3311,7 @@ int __alloc_bootmem_huge_page(struct hstate *h, int= nid) > goto found; > } > /* allocate from next node when distributing huge pages */ > - for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) = { > + for_each_node_mask_to_alloc(&h->next_nid_to_alloc, nr_nodes, node, &nod= e_states[N_MEMORY]) { > m =3D memblock_alloc_try_nid_raw( > huge_page_size(h), huge_page_size(h), > 0, MEMBLOCK_ALLOC_ACCESSIBLE, node); > @@ -3684,7 +3685,7 @@ static int adjust_pool_surplus(struct hstate *h, no= demask_t *nodes_allowed, > VM_BUG_ON(delta !=3D -1 && delta !=3D 1); > =20 > if (delta < 0) { > - for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { > + for_each_node_mask_to_alloc(&h->next_nid_to_alloc, nr_nodes, node, nod= es_allowed) { > if (h->surplus_huge_pages_node[node]) > goto found; > } > @@ -3799,7 +3800,8 @@ static int set_max_huge_pages(struct hstate *h, uns= igned long count, int nid, > cond_resched(); > =20 > folio =3D alloc_pool_huge_folio(h, nodes_allowed, > - node_alloc_noretry); > + node_alloc_noretry, > + &h->next_nid_to_alloc); > if (!folio) { > prep_and_add_allocated_folios(h, &page_list); > spin_lock_irq(&hugetlb_lock);