From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=sc8-sf-mx1.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1DsRpO-0006sw-N6 for user-mode-linux-devel@lists.sourceforge.net; Tue, 12 Jul 2005 13:58:06 -0700 Received: from agminet04.oracle.com ([141.146.126.231]) by sc8-sf-mx1.sourceforge.net with esmtp (Exim 4.44) id 1DsRpN-0005Ll-Kp for user-mode-linux-devel@lists.sourceforge.net; Tue, 12 Jul 2005 13:58:06 -0700 Received: from agminet04.oracle.com (localhost [127.0.0.1]) j6CKvxtw009990 for ; Tue, 12 Jul 2005 15:57:59 -0500 Received: from rgmsgw300.us.oracle.com (rgmsgw300.us.oracle.com [138.1.186.49])j6CKvxDA009970 for ; Tue, 12 Jul 2005 15:57:59 -0500 Received: from rgmsgw300.us.oracle.com (localhost [127.0.0.1]) j6CKvw6k016752 for ; Tue, 12 Jul 2005 14:57:58 -0600 Received: from [138.2.230.92] (agraves-lnx.us.oracle.com [138.2.230.92]) j6CKvw0j016745 (version=TLSv1/SSLv3 cipher=RC4-MD5 bits=128 verify=NO) for ; Tue, 12 Jul 2005 14:57:58 -0600 Message-ID: <42D42ED5.4000101@oracle.com> From: Allan Graves MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="------------000805080307050305080500" Subject: [uml-devel] Clarification of UML and AIO? Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: The user-mode Linux development list List-Post: List-Help: List-Subscribe: , List-Archive: Date: Tue, 12 Jul 2005 16:57:57 -0400 To: user-mode-linux-devel@lists.sourceforge.net This is a multi-part message in MIME format. --------------000805080307050305080500 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hi guys... Trying to do some AIO stuff here, and got a question. Perhaps I'm not understanding how AIO works in UML... Could someone perhaps give me an explanation of why we end up in pread, instead of aio? Does UML not support AIO through its block device driver? Thank you, Allan The simple test program: #include #include #include main() { struct aiocb aiocb; int fd; char buf[1024]; fd = open("/tmp/outfile", O_RDONLY); perror("open"); bzero(&aiocb, sizeof(aiocb)); aiocb.aio_fildes = fd; aiocb.aio_buf = buf; aiocb.aio_nbytes = sizeof(buf); aio_read(&aiocb); perror("aio_read"); while (aio_error(&aiocb) == EINPROGRESS); printf("buf = %s\n", buf); } Tracing the aio_read() through the UML kernel finally gets me here: #0 sys_pread64 (fd=3, buf=0xbf7c8f20 "", count=1024, pos=0) at fs/read_write.c:354 #1 0x08062ff8 in execute_syscall_skas (r=0x12374864) at arch/um/kernel/skas/syscall_kern.c:29 #2 0x0806302f in handle_syscall (regs=0x12374864) at arch/um/kernel/skas/syscall_user.c:25 #3 0x08062651 in userspace (regs=0x12374864) at arch/um/kernel/skas/process.c:91 #4 0x08062d44 in fork_handler (sig=10) at thread_info.h:47 #5 #6 0xffffe410 in __kernel_vsyscall () #7 0x00000000 in ?? () (gdb) --------------000805080307050305080500 Content-Type: text/x-vcard; charset=utf8; name="allan.graves.vcf" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="allan.graves.vcf" begin:vcard fn:Allan Graves n:Graves;Allan email;internet:allan.graves@oracle.com tel;work:603-8973276 x-mozilla-html:FALSE version:2.1 end:vcard --------------000805080307050305080500-- ------------------------------------------------------- This SF.Net email is sponsored by the 'Do More With Dual!' webinar happening July 14 at 8am PDT/11am EDT. We invite you to explore the latest in dual core and dual graphics technology at this free one hour event hosted by HP, AMD, and NVIDIA. To register visit http://www.hp.com/go/dualwebinar _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel