Hi Milan, On Mon, 28 Jan 2013 13:00:07 +0100 gmazyland at gmail.com (Milan Broz) wrote: > I need some real reason before submitting such patch. I am running a qnap TS-119P II NAS with Debian GNU/Linux. The device has a CESA crypto engine, which is supported by the in-mainline-kernel mv_cesa module. Unfortunately, this crypto engine exhibits the same symptoms as the one the author of this thread was describing: With small block sizes, the crypto engine is really slow. I have done a series of tests with a WD WD3000FYYZ SATA hard disk drive that achieves a raw read/write rate of about 177 MiB/s: dd if=/dev/sda2 of=/dev/null bs=1M count=4096 iflag=direct 4294967296 bytes (4.3 GB) copied, 24.2781 s, 177 MB/s dd if=/dev/zero of=/dev/sda2 bs=1M count=768 oflag=direct 805306368 bytes (805 MB) copied, 4.5337 s, 178 MB/s Using mv_cesa with aes-cbc-essiv:sha256 (one of the accelerated ciphers, as cryptsetup benchmark confirms), I get a rate of about 12.9 MiB/s: dd if=/dev/zero of=/dev/sda2_crypt bs=1M count=4096 oflag=direct 4294967296 bytes (4.3 GB) copied, 332.425 s, 12.9 MB/s There is a patch by Phil Sutter which makes mv_cesa use the TDMA engine of that SoC, and it improves performance quite a bit: dd if=/dev/zero of=/dev/mapper/sda2_crypt bs=1M count=1024 oflag=direct 1073741824 bytes (1.1 GB) copied, 50.5507 s, 21.2 MB/s This is just to let you know where I am coming from :). > That said... here is the patch which can use larger block size > option. It is not complete (mainly IV generators need changes and I > am afraid there should be morech changes than basic io hints) but it > should work for basic performance testing if you want to play with it > (you have to use dmsetup). > > So show your crypto performance numbers now :-) Thanks for posting this patch. I have set up my device as follows: echo "0 5858578432 crypt aes-cbc-essiv:sha256 0123456789abcdef0123456789abcdef 0 /dev/sda2 0 2 block_size 4096" | dmsetup create sda2_crypt The encryption rate improves significantly: dd if=/dev/zero of=/dev/mapper/sda2_crypt bs=1M count=1024 oflag=direct 1073741824 bytes (1.1 GB) copied, 26.4864 s, 40.5 MB/s I hope you realize that this is a real-world usecase for me — I cannot switch to a full-blown Intel system with AES-NI due to space and power efficiency reasons. Nevertheless, I need to encrypt my hard disk(s). I would appreciate it very much if you could implement the FIXME and commit that patch to dmcrypt. BTW, when using a block_size of more than 4096 (e.g. 8192), I get a kernel oops: [ 36.601704] device-mapper: ioctl: 4.23.1-ioctl (2012-12-18) initialised: dm-devel@xxxxxxxxxx [ 36.658525] bio: create slab <bio-1> at 1 [ 36.672332] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 36.680496] pgd = decf8000 [ 36.683212] [00000000] *pgd=1eeed831, *pte=00000000, *ppte=00000000 [ 36.689537] Internal error: Oops: 17 [#1] ARM [ 36.693911] Modules linked in: sha256_generic dm_crypt dm_mod nfsd auth_rpcgss nfs_acl nfs lockd dns_resolver fscache sunrpc hmac sha1_generic ehci_hcd mv_cesa mv643xx_eth usbcore inet_lro libphy usb_common mv_dma evdev loop gpio_keys autofs4 ext4 jbd2 mbcache sd_mod crc_t10dif sata_mv libata scsi_mod [ 36.720988] CPU: 0 Not tainted (3.8-trunk-kirkwood #1 Debian 3.8-1~experimental.2) [ 36.728940] PC is at create_empty_buffers+0x24/0x11c [ 36.733921] LR is at create_empty_buffers+0x14/0x11c [ 36.738899] pc : [<c00f44ec>] lr : [<c00f44dc>] psr: 80000013 [ 36.738899] sp : de8e5d10 ip : c04eb02c fp : c093d280 [ 36.750416] r10: 00100100 r9 : df6370b8 r8 : c093d280 [ 36.755658] r7 : dea39c80 r6 : 00000000 r5 : 00000000 r4 : c093d280 [ 36.762206] r3 : 00000000 r2 : 00000001 r1 : 00002000 r0 : 00000000 [ 36.768756] Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 36.775914] Control: 0005397f Table: 1ecf8000 DAC: 00000015 [ 36.781678] Process blkid (pid: 931, stack limit = 0xde8e41b8) [ 36.787530] Stack: (0xde8e5d10 to 0xde8e6000) [ 36.796608] 5d00: c093d280 df63717c 00000000 c00f4ad8 [ 36.806338] 5d20: 00000001 c00f4b14 c0502024 00000040 00000000 c055af38 00000010 000213d0 [ 36.816046] 5d40: 00000000 c0501a24 df637180 c00f9850 c093d280 df63717c 00000000 2ba657f0 [ 36.825732] 5d60: 000000d0 00200200 00100100 c0092b4c 60000013 00000001 df63717c 00000000 [ 36.833978] 5d80: dea39c80 c093d280 00200200 00100100 de8e5da0 c009b434 2ba657ff 2ba657f0 [ 36.844821] 5da0: de8e5da0 de8e5da0 91827364 de8e5dac de8e5dac de8e5db4 de8e5db4 00000000 [ 36.853045] 5dc0: c057bee0 00000000 00000001 2ba657f0 00000001 df63717c 000001ff dea39c80 [ 36.863832] 5de0: 00000000 c009b6c4 00000000 dea39c80 2ba657f0 00000000 00000001 00000000 [ 36.873483] 5e00: 00000000 2ba657f0 df63717c dea39c80 ffffffff c0093d08 00000001 00000000 [ 36.883145] 5e20: dea39c80 de8e5ec0 00000101 de8e5f00 657f0000 000002ba 00000fff b6f03000 [ 36.892789] 5e40: 000005b7 de8e5eb8 def41520 def6a1d8 decfadb8 00000028 00000000 de8e5ef8 [ 36.902532] 5e60: df6370b8 dea39cc0 2ba657f1 00000001 b6f031f0 00000000 00000000 00000040 [ 36.912233] 5e80: 0096ca78 00000000 c00f99e4 de8e5ec0 fffffdee de8e5f80 00000040 dea39c80 [ 36.921889] 5ea0: de8e4000 de8e5ec0 00000000 c00cd8b0 657f0000 000002ba 0096ca78 00000040 [ 36.931551] 5ec0: 00000000 00000000 00000000 00000001 ffffffff dea39c80 00000000 00000000 [ 36.941233] 5ee0: 00000000 00000000 dee603c0 00000000 00000000 00000000 657f0000 000002ba [ 36.950920] 5f00: 00000000 00000000 00000040 00000000 00000040 00000000 00000000 00000000 [ 36.960574] 5f20: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 36.970268] 5f40: 0096ca78 dea39c80 0096ca78 de8e5f80 00000000 00000040 00000040 c00cdfb4 [ 36.979934] 5f60: dea39c80 0096ca78 657f0000 000002ba dea39c80 00000000 0096ca78 c00ce0c4 [ 36.989635] 5f80: 657f0000 000002ba 00000040 0096ca70 00000040 0096c018 00000003 c000e508 [ 36.999297] 5fa0: 00000000 c000e380 0096ca70 00000040 00000003 0096ca78 00000040 00008000 [ 37.008957] 5fc0: 0096ca70 00000040 0096c018 00000003 657f0000 b6fc7000 0096ca58 00000000 [ 37.018632] 5fe0: 0096c064 bee91370 b6fac760 b6f0320c 60000010 00000003 00000000 00000000 [ 37.026882] [<c00f44ec>] (create_empty_buffers+0x24/0x11c) from [<c00f4ad8>] (create_page_buffers+0x34/0x4c) [ 37.036764] [<c00f4ad8>] (create_page_buffers+0x34/0x4c) from [<c00f4b14>] (block_read_full_page+0x24/0x358) [ 37.046646] [<c00f4b14>] (block_read_full_page+0x24/0x358) from [<c009b434>] (__do_page_cache_readahead+0x194/0x1ec) [ 37.057230] [<c009b434>] (__do_page_cache_readahead+0x194/0x1ec) from [<c009b6c4>] (force_page_cache_readahead+0x6c/0xa4) [ 37.068240] [<c009b6c4>] (force_page_cache_readahead+0x6c/0xa4) from [<c0093d08>] (generic_file_aio_read+0x290/0x6dc) [ 37.078906] [<c0093d08>] (generic_file_aio_read+0x290/0x6dc) from [<c00cd8b0>] (do_sync_read+0x90/0xcc) [ 37.088348] [<c00cd8b0>] (do_sync_read+0x90/0xcc) from [<c00cdfb4>] (vfs_read+0xa4/0x17c) [ 37.096569] [<c00cdfb4>] (vfs_read+0xa4/0x17c) from [<c00ce0c4>] (sys_read+0x38/0x64) [ 37.104447] [<c00ce0c4>] (sys_read+0x38/0x64) from [<c000e380>] (ret_fast_syscall+0x0/0x2c) [ 37.112924] Code: e1a05000 e1a03000 ea000000 e1a03001 (e5932000) [ 37.119055] ---[ end trace c844ca55a4ae58f6 ]--- -- Best regards, Michael _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx http://www.saout.de/mailman/listinfo/dm-crypt
