From nobody Sat Feb 7 11:30:49 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68FDAEB64DD for ; Fri, 21 Jul 2023 13:19:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229493AbjGUNTH (ORCPT ); Fri, 21 Jul 2023 09:19:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57310 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230140AbjGUNTD (ORCPT ); Fri, 21 Jul 2023 09:19:03 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C780930CF for ; Fri, 21 Jul 2023 06:18:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689945496; h=from:from: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=+qYMYKznWRCQRLs4itQFPGrBm6WN+EZaQC54fSpIxmA=; b=FTHaymwQzF2Qk9EwNilR3ERghSd0wsRO2bGEq3Jvwm7TdB7s8prLZYBALLbegbyToWui3o DNGwovFA87Gp6FbChE1caTSp3B2C7ewXesG2rR5f8iZPYAREMllz9WqVH/7mKU1UGqgCln JlIUSlq8NCIT8XKvdFU9lAOvbZyyhQI= Received: from mimecast-mx02.redhat.com (66.187.233.73 [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-617-zn0bPHkSOBi7QroqT667-g-1; Fri, 21 Jul 2023 09:18:13 -0400 X-MC-Unique: zn0bPHkSOBi7QroqT667-g-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C24F71C05154; Fri, 21 Jul 2023 13:18:12 +0000 (UTC) Received: from MiWiFi-R3L-srv.redhat.com (ovpn-12-18.pek2.redhat.com [10.72.12.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id F0A2C40C2071; Fri, 21 Jul 2023 13:18:08 +0000 (UTC) From: Baoquan He To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, akpm@linux-foundation.org, dennis@kernel.org, tj@kernel.org, cl@linux.com, mawupeng1@huawei.com, Baoquan He Subject: [PATCH 1/3] mm/percpu.c: remove redundant check Date: Fri, 21 Jul 2023 21:17:58 +0800 Message-Id: <20230721131800.20003-2-bhe@redhat.com> In-Reply-To: <20230721131800.20003-1-bhe@redhat.com> References: <20230721131800.20003-1-bhe@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The conditional check "(ai->dyn_size < PERCPU_DYNAMIC_EARLY_SIZE) has covered the check '(!ai->dyn_size)'. Signed-off-by: Baoquan He Acked-by: Dennis Zhou --- mm/percpu.c | 1 - 1 file changed, 1 deletion(-) diff --git a/mm/percpu.c b/mm/percpu.c index 28e07ede46f6..1480bf283d11 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -2615,7 +2615,6 @@ void __init pcpu_setup_first_chunk(const struct pcpu_= alloc_info *ai, PCPU_SETUP_BUG_ON(ai->unit_size < PCPU_MIN_UNIT_SIZE); PCPU_SETUP_BUG_ON(!IS_ALIGNED(ai->unit_size, PCPU_BITMAP_BLOCK_SIZE)); PCPU_SETUP_BUG_ON(ai->dyn_size < PERCPU_DYNAMIC_EARLY_SIZE); - PCPU_SETUP_BUG_ON(!ai->dyn_size); PCPU_SETUP_BUG_ON(!IS_ALIGNED(ai->reserved_size, PCPU_MIN_ALLOC_SIZE)); PCPU_SETUP_BUG_ON(!(IS_ALIGNED(PCPU_BITMAP_BLOCK_SIZE, PAGE_SIZE) || IS_ALIGNED(PAGE_SIZE, PCPU_BITMAP_BLOCK_SIZE))); --=20 2.34.1 From nobody Sat Feb 7 11:30:49 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5BEB7EB64DC for ; Fri, 21 Jul 2023 13:19:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230440AbjGUNTU (ORCPT ); Fri, 21 Jul 2023 09:19:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57480 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230140AbjGUNTR (ORCPT ); Fri, 21 Jul 2023 09:19:17 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA8A630D0 for ; Fri, 21 Jul 2023 06:18:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689945504; h=from:from: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=LHVCmyopA5Gpa/p3+Tf6DYpT7yyPaihL3mV5AOHJdCk=; b=XAzIyho8/DboWSj3xN/J/72F8nZmEkC0lmX2CB/0WnpqFvwS3Zf0LcJOrqD5HmMr7MJ2Cr Laubjc3eX7yBEt2j7QX5o9n2Y6uJZuD6xj90IzeEWrz+U7N0rOK5lPRMDh/Wz1rYjFEpAC bj8vUGDdyrDg3aB9r7XbMfrOl18IyvY= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-46-gPqUh22iP5KQ72sCd8VWSA-1; Fri, 21 Jul 2023 09:18:18 -0400 X-MC-Unique: gPqUh22iP5KQ72sCd8VWSA-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 7C41080123E; Fri, 21 Jul 2023 13:18:17 +0000 (UTC) Received: from MiWiFi-R3L-srv.redhat.com (ovpn-12-18.pek2.redhat.com [10.72.12.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id 771C540C2071; Fri, 21 Jul 2023 13:18:13 +0000 (UTC) From: Baoquan He To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, akpm@linux-foundation.org, dennis@kernel.org, tj@kernel.org, cl@linux.com, mawupeng1@huawei.com, Baoquan He Subject: [PATCH 2/3] mm/percpu.c: optimize the code in pcpu_setup_first_chunk() a little bit Date: Fri, 21 Jul 2023 21:17:59 +0800 Message-Id: <20230721131800.20003-3-bhe@redhat.com> In-Reply-To: <20230721131800.20003-1-bhe@redhat.com> References: <20230721131800.20003-1-bhe@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" This removes the need of local varibale 'chunk', and optimize the code calling pcpu_alloc_first_chunk() to initialize reserved chunk and dynamic chunk to make it simpler. Signed-off-by: Baoquan He --- mm/percpu.c | 32 +++++++++++++------------------- 1 file changed, 13 insertions(+), 19 deletions(-) diff --git a/mm/percpu.c b/mm/percpu.c index 1480bf283d11..c25b058a46ad 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -2581,7 +2581,6 @@ void __init pcpu_setup_first_chunk(const struct pcpu_= alloc_info *ai, { size_t size_sum =3D ai->static_size + ai->reserved_size + ai->dyn_size; size_t static_size, dyn_size; - struct pcpu_chunk *chunk; unsigned long *group_offsets; size_t *group_sizes; unsigned long *unit_off; @@ -2697,7 +2696,7 @@ void __init pcpu_setup_first_chunk(const struct pcpu_= alloc_info *ai, pcpu_unit_pages =3D ai->unit_size >> PAGE_SHIFT; pcpu_unit_size =3D pcpu_unit_pages << PAGE_SHIFT; pcpu_atom_size =3D ai->atom_size; - pcpu_chunk_struct_size =3D struct_size(chunk, populated, + pcpu_chunk_struct_size =3D struct_size((struct pcpu_chunk *)0, populated, BITS_TO_LONGS(pcpu_unit_pages)); =20 pcpu_stats_save_ai(ai); @@ -2735,28 +2734,23 @@ void __init pcpu_setup_first_chunk(const struct pcp= u_alloc_info *ai, =20 /* * Initialize first chunk. - * If the reserved_size is non-zero, this initializes the reserved - * chunk. If the reserved_size is zero, the reserved chunk is NULL - * and the dynamic region is initialized here. The first chunk, - * pcpu_first_chunk, will always point to the chunk that serves - * the dynamic region. + * If the reserved_size is non-zero, initializes the reserved chunk + * firstly. If the reserved_size is zero, the reserved chunk is NULL + * and the dynamic region is initialized directly. The first chunk, + * pcpu_first_chunk, will always point to the chunk that serves the + * dynamic region. */ tmp_addr =3D (unsigned long)base_addr + static_size; - map_size =3D ai->reserved_size ?: dyn_size; - chunk =3D pcpu_alloc_first_chunk(tmp_addr, map_size); - - /* init dynamic chunk if necessary */ if (ai->reserved_size) { - pcpu_reserved_chunk =3D chunk; - - tmp_addr =3D (unsigned long)base_addr + static_size + - ai->reserved_size; - map_size =3D dyn_size; - chunk =3D pcpu_alloc_first_chunk(tmp_addr, map_size); + map_size =3D ai->reserved_size; + pcpu_reserved_chunk =3D pcpu_alloc_first_chunk(tmp_addr, map_size); } =20 - /* link the first chunk in */ - pcpu_first_chunk =3D chunk; + /* init dynamic chunk if necessary */ + tmp_addr +=3D (unsigned long)ai->reserved_size; + map_size =3D dyn_size; + pcpu_first_chunk =3D pcpu_alloc_first_chunk(tmp_addr, map_size); + pcpu_nr_empty_pop_pages =3D pcpu_first_chunk->nr_empty_pop_pages; pcpu_chunk_relocate(pcpu_first_chunk, -1); =20 --=20 2.34.1 From nobody Sat Feb 7 11:30:49 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D5847C001E0 for ; Fri, 21 Jul 2023 13:19:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230483AbjGUNTX (ORCPT ); Fri, 21 Jul 2023 09:19:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57520 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230436AbjGUNTU (ORCPT ); Fri, 21 Jul 2023 09:19:20 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 764662130 for ; Fri, 21 Jul 2023 06:18:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689945504; h=from:from: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3RZSzIkl7Lg2t6SJUFm5Lmk6ZzRLZxYILlnvYuCsuFM=; b=aZ/TL7VthrpYJswHCVw9Fbv+oEl2nq9+mHRl5s4tVzozTUs+sVb4zv5UOoqQ+y7+RfQaoX D2R09/ABXFqE313maF+3DAAZ4ibLkvGieWzW0Wee1KcoBgqCufK33cKGtjTuTczKtSmto9 iShav6UWmp8VVPChHpFcDPGmrV7r7rs= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-372-A6k7ExN7MsehoQtAg3USbQ-1; Fri, 21 Jul 2023 09:18:22 -0400 X-MC-Unique: A6k7ExN7MsehoQtAg3USbQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6879A8F184A; Fri, 21 Jul 2023 13:18:22 +0000 (UTC) Received: from MiWiFi-R3L-srv.redhat.com (ovpn-12-18.pek2.redhat.com [10.72.12.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4DF6540C2073; Fri, 21 Jul 2023 13:18:17 +0000 (UTC) From: Baoquan He To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, akpm@linux-foundation.org, dennis@kernel.org, tj@kernel.org, cl@linux.com, mawupeng1@huawei.com, Baoquan He Subject: [PATCH 3/3] mm/percpu.c: print error message too if atomic alloc failed Date: Fri, 21 Jul 2023 21:18:00 +0800 Message-Id: <20230721131800.20003-4-bhe@redhat.com> In-Reply-To: <20230721131800.20003-1-bhe@redhat.com> References: <20230721131800.20003-1-bhe@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The variable 'err' is assgigned to an error message if atomic alloc failed, while it has no chance to be printed if is_atomic is true. Here change to print error message too if atomic alloc failed, while avoid to call dump_stack() if that case. Signed-off-by: Baoquan He --- mm/percpu.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/mm/percpu.c b/mm/percpu.c index c25b058a46ad..74f75ef0ad58 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -1890,13 +1890,15 @@ static void __percpu *pcpu_alloc(size_t size, size_= t align, bool reserved, fail: trace_percpu_alloc_percpu_fail(reserved, is_atomic, size, align); =20 - if (!is_atomic && do_warn && warn_limit) { + if (do_warn && warn_limit) { pr_warn("allocation failed, size=3D%zu align=3D%zu atomic=3D%d, %s\n", size, align, is_atomic, err); - dump_stack(); + if (is_atomic) + dump_stack(); if (!--warn_limit) pr_info("limit reached, disable warning\n"); } + if (is_atomic) { /* see the flag handling in pcpu_balance_workfn() */ pcpu_atomic_alloc_failed =3D true; --=20 2.34.1