From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262198AbTKRBP0 (ORCPT ); Mon, 17 Nov 2003 20:15:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262224AbTKRBP0 (ORCPT ); Mon, 17 Nov 2003 20:15:26 -0500 Received: from fw.osdl.org ([65.172.181.6]:64221 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S262198AbTKRBPT (ORCPT ); Mon, 17 Nov 2003 20:15:19 -0500 Subject: Re: 2.6.0-test9-mm3 - AIO test results From: Daniel McNeil To: Suparna Bhattacharya Cc: Andrew Morton , Linux Kernel Mailing List , linux-mm@kvack.org, "linux-aio@kvack.org" In-Reply-To: <20031117052518.GA11184@in.ibm.com> References: <20031112233002.436f5d0c.akpm@osdl.org> <1068761038.1805.35.camel@ibm-c.pdx.osdl.net> <20031117052518.GA11184@in.ibm.com> Content-Type: text/plain Organization: Message-Id: <1069118109.1842.31.camel@ibm-c.pdx.osdl.net> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.2 (1.2.2-5) Date: 17 Nov 2003 17:15:09 -0800 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Suparna, Good news and bad news. Your patch does fix the non-power of two i/o size problems where AIO previously did not complete: $ ./aiodio_sparse -s 1751k -r 18k -w 11k $ aiodio_sparse -i 9 -dd -s 180k -r 18k -w 18k io_submit() return 9 aiodio_sparse: 9 i/o in flight aiodio_sparse: offset 165888 filesize 184320 inflight 9 aiodio_sparse: io_getevent() returned 1 aiodio_sparse: io_getevent() res 18432 res2 0 io_submit() return 1 AIO DIO write done unlinking file dio_sparse done writing, kill children aiodio_sparse 0 children had errors But when testing using aiocp using O_DIRECT to copy a file to an already allocated file, the aiocp process hangs. I used i/o size of 4k and that compeleted. Using i/o size of 1k and 2k, the aiocp process hung during io_sumbit() and are unkillable. Here are the stack traces: # ps -fu daniel | grep aiocp daniel 1920 1 0 16:45 ? 00:00:07 aiocp -b 1k -n 1 -f DIRECT glibc-2.3.2.tar ff2 daniel 2083 2037 0 17:00 pts/2 00:00:03 aiocp -dd -b 1k -n 8 -f DIRECT glibc-2.3.2.tar ff2 aiocp D 00000001 1920 1 1902 (NOTLB) e70abd04 00200086 c18dbc80 00000001 00000003 c02897fc 00000060 00200246 f7cdb8b4 c16522f0 c18dbc80 0000309c 640a05eb 0000008b e6d9e660 c0289a16 f7cdb8b4 e87e95cc c18dbc80 00000000 00000001 e70abd10 c0123712 e70aa000 Call Trace: [] generic_unplug_device+0x50/0xbd [] blk_run_queues+0xa9/0x15c [] io_schedule+0x26/0x30 [] direct_io_worker+0x376/0x5ab [] generic_file_direct_IO+0x70/0x89 [] __blockdev_direct_IO+0x1d3/0x2d5 [] ext3_direct_io_get_blocks+0x0/0xbf [] ext3_direct_IO+0xc0/0x1e1 [] ext3_direct_io_get_blocks+0x0/0xbf [] generic_file_direct_IO+0x70/0x89 [] __generic_file_aio_read+0xfb/0x1ff [] schedule+0x3ac/0x7ef [] generic_file_aio_read+0x33/0x37 [] aio_pread+0x34/0x5f [] aio_run_iocb+0xa6/0x1ed [] __aio_get_req+0x27/0x158 [] aio_pread+0x0/0x5f [] io_submit_one+0x1ea/0x2b7 [] sys_io_submit+0xe1/0x194 [] syscall_call+0x7/0xb [] rpc_depopulate+0x1aa/0x24b aiocp D 366EDC94 2083 2037 (NOTLB) e758bd04 00200082 f71ba000 366edc94 00000161 c02897fc 00000060 366edc94 00000161 f71ba000 c18d3c80 000069a9 366f5a0e 00000161 e8d4acc0 c0289a16 f7cdb8b4 e960465c c18d3c80 00000000 00000001 e758bd10 c0123712 e758a000 Call Trace: [] generic_unplug_device+0x50/0xbd [] blk_run_queues+0xa9/0x15c [] io_schedule+0x26/0x30 [] direct_io_worker+0x376/0x5ab [] __blockdev_direct_IO+0x1d3/0x2d5 [] ext3_direct_io_get_blocks+0x0/0xbf [] ext3_direct_IO+0xc0/0x1e1 [] ext3_direct_io_get_blocks+0x0/0xbf [] generic_file_direct_IO+0x70/0x89 [] __generic_file_aio_read+0xfb/0x1ff [] write_chan+0x165/0x21e [] generic_file_aio_read+0x33/0x37 [] aio_pread+0x34/0x5f [] aio_run_iocb+0xa6/0x1ed [] __aio_get_req+0x27/0x158 [] aio_pread+0x0/0x5f [] tty_write+0x1e8/0x3b2 [] io_submit_one+0x1ea/0x2b7 [] sys_io_submit+0xe1/0x194 [] syscall_call+0x7/0xb [] rpc_depopulate+0x1aa/0x24b Daniel On Sun, 2003-11-16 at 21:25, Suparna Bhattacharya wrote: > On Thu, Nov 13, 2003 at 02:03:58PM -0800, Daniel McNeil wrote: > > Andrew, > > > > I'm testing test9-mm3 on a 2-proc Xeon with a ext3 file system. > > I tested using the test programs aiocp and aiodio_sparse. > > (see http://developer.osdl.org/daniel/AIO/) > > > > Using aiocp with i/o sizes from 1k to 512k to copy files worked > > without any errors or kernel debug messages. > > > > With 64k i/o, the aiodio_sparse program complete without any errors. > > There are no kernel error messages, so that is good. > > > > There are still problems with non power of 2 i/o sizes using AIO and > > O_DIRECT. It hangs with aio's that do not seem to complete. The test > > does exit when hitting ^c and there are no kernel messages. Test output > > below: > > Could you check if the following patch fixes the problem for you ? > > Regards > Suparna > > -------------------------------------------------------------- > > With this patch, when the DIO code falls back to buffered i/o after > having submitted part of the i/o, then buffered i/o is issued only > for the remaining part of the request (i.e. the part not already > covered by DIO). > > diff -ur pure-mm3/fs/direct-io.c linux-2.6.0-test9-mm3/fs/direct-io.c > --- pure-mm3/fs/direct-io.c 2003-11-14 09:09:06.000000000 +0530 > +++ linux-2.6.0-test9-mm3/fs/direct-io.c 2003-11-17 09:00:47.000000000 +0530 > @@ -74,6 +74,7 @@ > been performed at the start of a > write */ > int pages_in_io; /* approximate total IO pages */ > + size_t size; /* total request size (doesn't change)*/ > sector_t block_in_file; /* Current offset into the underlying > file in dio_block units. */ > unsigned blocks_available; /* At block_in_file. changes */ > @@ -226,7 +227,7 @@ > dio_complete(dio, dio->block_in_file << dio->blkbits, > dio->result); > /* Complete AIO later if falling back to buffered i/o */ > - if (dio->result != -ENOTBLK) { > + if (dio->result >= dio->size || dio->rw == READ) { > aio_complete(dio->iocb, dio->result, 0); > kfree(dio); > } else { > @@ -889,6 +890,7 @@ > dio->blkbits = blkbits; > dio->blkfactor = inode->i_blkbits - blkbits; > dio->start_zero_done = 0; > + dio->size = 0; > dio->block_in_file = offset >> blkbits; > dio->blocks_available = 0; > dio->cur_page = NULL; > @@ -925,7 +927,7 @@ > > for (seg = 0; seg < nr_segs; seg++) { > user_addr = (unsigned long)iov[seg].iov_base; > - bytes = iov[seg].iov_len; > + dio->size += bytes = iov[seg].iov_len; > > /* Index into the first page of the first block */ > dio->first_block_in_page = (user_addr & ~PAGE_MASK) >> blkbits; > @@ -956,6 +958,13 @@ > } > } /* end iovec loop */ > > + if (ret == -ENOTBLK && rw == WRITE) { > + /* > + * The remaining part of the request will be > + * be handled by buffered I/O when we return > + */ > + ret = 0; > + } > /* > * There may be some unwritten disk at the end of a part-written > * fs-block-sized block. Go zero that now. > @@ -986,19 +995,13 @@ > */ > if (dio->is_async) { > if (ret == 0) > - ret = dio->result; /* Bytes written */ > - if (ret == -ENOTBLK) { > - /* > - * The request will be reissued via buffered I/O > - * when we return; Any I/O already issued > - * effectively becomes redundant. > - */ > - dio->result = ret; > + ret = dio->result; > + if (ret > 0 && dio->result < dio->size && rw == WRITE) { > dio->waiter = current; > } > finished_one_bio(dio); /* This can free the dio */ > blk_run_queues(); > - if (ret == -ENOTBLK) { > + if (dio->waiter) { > /* > * Wait for already issued I/O to drain out and > * release its references to user-space pages > @@ -1032,7 +1035,8 @@ > } > dio_complete(dio, offset, ret); > /* We could have also come here on an AIO file extend */ > - if (!is_sync_kiocb(iocb) && (ret != -ENOTBLK)) > + if (!is_sync_kiocb(iocb) && !(rw == WRITE && ret >= 0 && > + dio->result < dio->size)) > aio_complete(iocb, ret, 0); > kfree(dio); > } > diff -ur pure-mm3/mm/filemap.c linux-2.6.0-test9-mm3/mm/filemap.c > --- pure-mm3/mm/filemap.c 2003-11-14 09:15:08.000000000 +0530 > +++ linux-2.6.0-test9-mm3/mm/filemap.c 2003-11-15 11:11:16.000000000 +0530 > @@ -1895,14 +1895,16 @@ > */ > if (written >= 0 && file->f_flags & O_SYNC) > status = generic_osync_inode(inode, mapping, OSYNC_METADATA); > - if (written >= 0 && !is_sync_kiocb(iocb)) > + if (written >= count && !is_sync_kiocb(iocb)) > written = -EIOCBQUEUED; > - if (written != -ENOTBLK) > + if (written < 0 || written >= count) > goto out_status; > /* > * direct-io write to a hole: fall through to buffered I/O > + * for completing the rest of the request. > */ > - written = 0; > + pos += written; > + count -= written; > } > > buf = iov->iov_base;