From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-3.3 required=5.0 tests=HTML_MESSAGE, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 12327 invoked from network); 13 Jan 2022 03:10:12 -0000 Received: from mother.openwall.net (195.42.179.200) by inbox.vuxu.org with ESMTPUTF8; 13 Jan 2022 03:10:12 -0000 Received: (qmail 14092 invoked by uid 550); 13 Jan 2022 03:10:10 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: musl@lists.openwall.com Received: (qmail 14050 invoked from network); 13 Jan 2022 03:10:09 -0000 From: "zhaohang (F)" To: "musl@lists.openwall.com" CC: "zhangwentao (M)" Thread-Topic: [musl] What's the purpose of the __vm_lock? Thread-Index: AdgIJsYiekAfClchSLKwmXEyyocGzA== Date: Thu, 13 Jan 2022 03:09:55 +0000 Message-ID: Accept-Language: zh-CN, en-US Content-Language: zh-CN X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.174.176.241] Content-Type: multipart/alternative; boundary="_000_e457d3dcb3b84e39ae7e9761216d3783huaweicom_" MIME-Version: 1.0 X-CFilter-Loop: Reflected Subject: [musl] What's the purpose of the __vm_lock? --_000_e457d3dcb3b84e39ae7e9761216d3783huaweicom_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Hello, I'm a little confused about the usefulness of __vm_lock. It seems like that= __vm_lock was originally cited to prevent the data race condition between = pthread_barrier_wait and virtual memory changing, but it can not ensure tha= t the virtual memory of the barrier will not be changed before pthread_barr= ier_wait. So, what is the meaning that introduce the __vm_lock to prevent t= he data race? Thank you. --_000_e457d3dcb3b84e39ae7e9761216d3783huaweicom_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Hello,

 

I'm a little confused about the= usefulness of __vm_lock. It seems like that __vm_lock was originally cited= to prevent the data race condition between pthread_barrier_wait and virtua= l memory changing, but it can not ensure that the virtual memory of the barrier will not be changed before pthread_= barrier_wait. So, what is the meaning that introduce the __vm_lock to preve= nt the data race?

 

Thank you.=

 

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