From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 226E8C433E2 for ; Tue, 9 Jun 2020 04:33:37 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D093D20810 for ; Tue, 9 Jun 2020 04:33:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="afjPaoo6" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D093D20810 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 746818D000A; Tue, 9 Jun 2020 00:33:36 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 71D656B00BE; Tue, 9 Jun 2020 00:33:36 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 633C38D000A; Tue, 9 Jun 2020 00:33:36 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0086.hostedemail.com [216.40.44.86]) by kanga.kvack.org (Postfix) with ESMTP id 43D086B00BD for ; Tue, 9 Jun 2020 00:33:36 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 108FA1802F04F for ; Tue, 9 Jun 2020 04:33:36 +0000 (UTC) X-FDA: 76908404832.10.rake95_0b1304026dbf Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin10.hostedemail.com (Postfix) with ESMTP id D56F316A4C2 for ; Tue, 9 Jun 2020 04:33:35 +0000 (UTC) X-HE-Tag: rake95_0b1304026dbf X-Filterd-Recvd-Size: 4217 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf22.hostedemail.com (Postfix) with ESMTP for ; Tue, 9 Jun 2020 04:33:35 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 24F4720801; Tue, 9 Jun 2020 04:33:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591677214; bh=TD+E02Q/fiTyzCWlaArRXpAY1tCfQ6RiiUdaRl3zs8A=; h=Date:From:To:Subject:In-Reply-To:From; b=afjPaoo6OqAdFAFczwlsTmcinrywwq95QL84KM1FZqNKnEuPBEZbnueSH+9OjT5Jt BPgTWYbRm+Uy7+osKgRhbQ8d3AkEV7xXKsp5Gmro6XxX5xqEOacdjwftUWqiSKIY0n MxsU1+zFUQe7hZtvrBqZeu/0dYFh5DmeOgJgnhqY= Date: Mon, 08 Jun 2020 21:33:33 -0700 From: Andrew Morton To: akpm@linux-foundation.org, daniel.m.jordan@oracle.com, dbueso@suse.de, hughd@google.com, jgg@ziepe.ca, jglisse@redhat.com, jhubbard@nvidia.com, ldufour@linux.ibm.com, Liam.Howlett@oracle.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, peterz@infradead.org, rientjes@google.com, torvalds@linux-foundation.org, vbabka@suse.cz, walken@google.com, willy@infradead.org, yinghan@google.com Subject: [patch 65/93] mmap locking API: convert nested write lock sites Message-ID: <20200609043333.jlWUJ02cB%akpm@linux-foundation.org> In-Reply-To: <20200608212922.5b7fa74ca3f4e2444441b7f9@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Queue-Id: D56F316A4C2 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam01 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: Michel Lespinasse Subject: mmap locking API: convert nested write lock sites Add API for nested write locks and convert the few call sites doing that. Link: http://lkml.kernel.org/r/20200520052908.204642-7-walken@google.com Signed-off-by: Michel Lespinasse Reviewed-by: Daniel Jordan Reviewed-by: Laurent Dufour Reviewed-by: Vlastimil Babka Cc: Davidlohr Bueso Cc: David Rientjes Cc: Hugh Dickins Cc: Jason Gunthorpe Cc: Jerome Glisse Cc: John Hubbard Cc: Liam Howlett Cc: Matthew Wilcox Cc: Peter Zijlstra Cc: Ying Han Signed-off-by: Andrew Morton --- arch/um/include/asm/mmu_context.h | 3 ++- include/linux/mmap_lock.h | 5 +++++ kernel/fork.c | 2 +- 3 files changed, 8 insertions(+), 2 deletions(-) --- a/arch/um/include/asm/mmu_context.h~mmap-locking-api-convert-nested-write-lock-sites +++ a/arch/um/include/asm/mmu_context.h @@ -8,6 +8,7 @@ #include #include +#include #include @@ -47,7 +48,7 @@ static inline void activate_mm(struct mm * when the new ->mm is used for the first time. */ __switch_mm(&new->context.id); - down_write_nested(&new->mmap_sem, 1); + mmap_write_lock_nested(new, SINGLE_DEPTH_NESTING); uml_setup_stubs(new); mmap_write_unlock(new); } --- a/include/linux/mmap_lock.h~mmap-locking-api-convert-nested-write-lock-sites +++ a/include/linux/mmap_lock.h @@ -11,6 +11,11 @@ static inline void mmap_write_lock(struc down_write(&mm->mmap_sem); } +static inline void mmap_write_lock_nested(struct mm_struct *mm, int subclass) +{ + down_write_nested(&mm->mmap_sem, subclass); +} + static inline int mmap_write_lock_killable(struct mm_struct *mm) { return down_write_killable(&mm->mmap_sem); --- a/kernel/fork.c~mmap-locking-api-convert-nested-write-lock-sites +++ a/kernel/fork.c @@ -501,7 +501,7 @@ static __latent_entropy int dup_mmap(str /* * Not linked in yet - no deadlock potential: */ - down_write_nested(&mm->mmap_sem, SINGLE_DEPTH_NESTING); + mmap_write_lock_nested(mm, SINGLE_DEPTH_NESTING); /* No ordering required: file already has been exposed. */ RCU_INIT_POINTER(mm->exe_file, get_mm_exe_file(oldmm)); _