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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=ham 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 D5E12C352BE for ; Wed, 15 Apr 2020 00:44:00 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9A636206D9 for ; Wed, 15 Apr 2020 00:44:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ppeFKkXH" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9A636206D9 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 453968E0006; Tue, 14 Apr 2020 20:44:00 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 402E58E0001; Tue, 14 Apr 2020 20:44:00 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 319FE8E0006; Tue, 14 Apr 2020 20:44:00 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0046.hostedemail.com [216.40.44.46]) by kanga.kvack.org (Postfix) with ESMTP id 1AFFB8E0001 for ; Tue, 14 Apr 2020 20:44:00 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id D705E180AD807 for ; Wed, 15 Apr 2020 00:43:59 +0000 (UTC) X-FDA: 76708242198.25.girl54_3ff5d7542023f X-HE-Tag: girl54_3ff5d7542023f X-Filterd-Recvd-Size: 5601 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) by imf16.hostedemail.com (Postfix) with ESMTP for ; Wed, 15 Apr 2020 00:43:59 +0000 (UTC) Received: by mail-pl1-f201.google.com with SMTP id a8so1407987plm.2 for ; Tue, 14 Apr 2020 17:43:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=l94C8AK+mUgLYQwrQ+fXnOHMPf8DqDjIiWG1XX6H7Ec=; b=ppeFKkXHMm35q46GgKPv9sdZ6Tqxtm1z5m3TTB4oOmL4XBF34pgNgI6POCdpKssT/N v8CbRWth1V61g5Htw4NIsfPEuz2B/zrwMCC0nV3MUriV9RMFMz2ctgkgeaadhIT3cL9W 42UjpsCFHJxtX7awBdUm2MxhirlGajVmngK5A5fEkaKV8l/xjNAbUjXgY7Sw8DZsOyKJ nc1afK8YKYkFVJLXNntGuukspPexoy1FK2YyevBcpjZ+pTS//WjwfA5HEclvXDHM2vxu nSDzpc6Bzic4DDLDekRerWGm53M6OIWmxgn/tHhHztto5f+d8cxcOdKZo5rLfWY4KAQM zBAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=l94C8AK+mUgLYQwrQ+fXnOHMPf8DqDjIiWG1XX6H7Ec=; b=fWAkAdVXkjf3m0QHaqSHa84gZqCBv30ifmczV59ZKnjdNbvPO2EGc2WIj2n+z/ZlYc 5BePw82AycOkc6zSdTiIpMFGMEbHZvujnbhSdleLNXKI8wfhmOCkz0JnsGrvSPrlSdDb qAnpdWxy3EziWAe9psciOYkxw83ImFqDw7UgFpJtU1kR3jWbM3hMrQ6s/gZJFk/hmRiI 0X6Nv7i+Lgf6ZNlF9kMqTwdl5ghCWPORAgzWMjxsHuh2xj9qBoGO2vASrJerzkBgbs7H 5OpRsyItBY0SotR7Q4yBJ23PNOoS9bxBTSMZoNtu3LM+mgtjnjj8nL4uDiRS8nwCeyfQ S5Qw== X-Gm-Message-State: AGi0PuYPfgDF7c+BTWnmiZhYqbcAJ+/vEfmgxwY6ljsExIfY60iKwOHy aOGT9vb1fNwBs3SntRGZXJZg+Rz2Zdo= X-Google-Smtp-Source: APiQypLqLcVmwiH9GYjRHsC6Au6hrD2No9rLdY7vhYQd1JK6hU4NUeWrBiYgMQdiT4ZiLVjhe+Vuo2tOODA= X-Received: by 2002:a17:90a:1a10:: with SMTP id 16mr3269326pjk.31.1586911438402; Tue, 14 Apr 2020 17:43:58 -0700 (PDT) Date: Tue, 14 Apr 2020 17:43:44 -0700 In-Reply-To: <20200415004353.130248-1-walken@google.com> Message-Id: <20200415004353.130248-2-walken@google.com> Mime-Version: 1.0 References: <20200415004353.130248-1-walken@google.com> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog Subject: [PATCH v4 01/10] mmap locking API: initial implementation as rwsem wrappers From: Michel Lespinasse To: Andrew Morton , linux-mm Cc: LKML , Peter Zijlstra , Laurent Dufour , Vlastimil Babka , Matthew Wilcox , Liam Howlett , Jerome Glisse , Davidlohr Bueso , David Rientjes , Hugh Dickins , Ying Han , Jason Gunthorpe , Daniel Jordan , Michel Lespinasse Content-Type: text/plain; charset="UTF-8" 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: This change wraps the existing mmap_sem related rwsem calls into a new mmap locking API. There are two justifications for the new API: - At first, it provides an easy hooking point to instrument mmap_sem locking latencies independently of any other rwsems. - In the future, it may be a starting point for replacing the rwsem implementation with a different one, such as range locks. Signed-off-by: Michel Lespinasse Reviewed-by: Daniel Jordan --- include/linux/mm.h | 1 + include/linux/mmap_lock.h | 54 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 55 insertions(+) create mode 100644 include/linux/mmap_lock.h diff --git a/include/linux/mm.h b/include/linux/mm.h index 5a323422d783..051ec782bdbb 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include diff --git a/include/linux/mmap_lock.h b/include/linux/mmap_lock.h new file mode 100644 index 000000000000..8b5a3cd56118 --- /dev/null +++ b/include/linux/mmap_lock.h @@ -0,0 +1,54 @@ +#ifndef _LINUX_MMAP_LOCK_H +#define _LINUX_MMAP_LOCK_H + +static inline void mmap_init_lock(struct mm_struct *mm) +{ + init_rwsem(&mm->mmap_sem); +} + +static inline void mmap_write_lock(struct mm_struct *mm) +{ + down_write(&mm->mmap_sem); +} + +static inline int mmap_write_lock_killable(struct mm_struct *mm) +{ + return down_write_killable(&mm->mmap_sem); +} + +static inline bool mmap_write_trylock(struct mm_struct *mm) +{ + return down_write_trylock(&mm->mmap_sem) != 0; +} + +static inline void mmap_write_unlock(struct mm_struct *mm) +{ + up_write(&mm->mmap_sem); +} + +static inline void mmap_downgrade_write_lock(struct mm_struct *mm) +{ + downgrade_write(&mm->mmap_sem); +} + +static inline void mmap_read_lock(struct mm_struct *mm) +{ + down_read(&mm->mmap_sem); +} + +static inline int mmap_read_lock_killable(struct mm_struct *mm) +{ + return down_read_killable(&mm->mmap_sem); +} + +static inline bool mmap_read_trylock(struct mm_struct *mm) +{ + return down_read_trylock(&mm->mmap_sem) != 0; +} + +static inline void mmap_read_unlock(struct mm_struct *mm) +{ + up_read(&mm->mmap_sem); +} + +#endif /* _LINUX_MMAP_LOCK_H */ -- 2.26.0.110.g2183baf09c-goog