LSI - MR-Fusion controller driver <mrsas> patch and man page

Mon Jan 6 08:17:49 UTC 2014

Doug:

I have replied inline for your comment. For most of the comment you posted below can be work out and we can prioritize completion of those based on nature of issue.
I will work on READ/WRITE comparison w.r.t <mfi> and <mrsas> as a priority item. 

Please consider that it will be really helpful for further development, if we have common code check-in in Upstream FreeBSD. We will actively work on each comment posted for <mrsas> and address those before we have <mrsas> in-box for any FreeBSD release.

Thanks, Kashyap

> -----Original Message-----
> From: Doug Ambrisko [mailto:ambrisko at cisco.com]
> Sent: Saturday, January 04, 2014 2:45 AM
> To: Desai, Kashyap
> Cc: freebsd-scsi at freebsd.org; scottl at netflix.com; sean_bruno at yahoo.com;
> dwhite at ixsystems.com; jpaetzel at freebsd.org; Maloy, Joe; Mankani,
> Krishnaraddi; McConnell, Stephen; Saxena, Sumit; Radford, Adam; Kenneth
> D. Merry
> Subject: Re: LSI - MR-Fusion controller driver <mrsas> patch and man page
> 
> On Fri, Dec 06, 2013 at 02:37:21PM +0000, Desai, Kashyap wrote:
> | Hi,
> |
> | Please consider attached patch for FreeBSD upstream check-in.
> |
> | Please find attached patch for <mrsas> driver for LSI's MegaRaid
> Controllers. This driver supports Thunderbolt onwards Device IDs of MR
> controllers.
> | Currently it supports 0x005B and 0x005D Device IDs.
> |
> | NOTE : This driver will not eliminate or by pass any functionality of <mfi>
> driver which already support above to Device IDs to keep existing user
> experience unchanged.
> |
> | <mfi> Driver will be always given priority over <mrsas> driver and
> | only if customer/user wants to use/migrate from <mfi> to <mrsas>, it
> | will hook up into kernel via device.hint rules. (Attached is mrsas man
> | page for more info.)
> |
> | LSI will continue to update <mrsas> driver in future in timely bases.
> | We have another set of patch in pipeline to be submitted for <mrsas>,
> | but need first go ahead for attached patch and later we will continue
> | to keep <mrsas> up-to-date (In sync with LSI released driver which is
> | available at lsi's external site)
> |
> | Apply patch with "patch -p0 < patchname.patch" from head directory.
> |
> | -- Few notes for user--
> | LSI recommends using fusion_force bit In hint settings at start of the day, if
> they want to use <mrsas>. ( <mfi> will be a default choice for MR-Fusion
> HBA), if will be changed only with fusion_force hint settings. (See mrsas man
> page) Changing any default behavior is well tested for most of the condition.
> | Switching from <mfi> to <mrsas> for MR-Fusion options is designed to
> allow user as one time choice, though multiple time switch from <mfi> to
> <mrsas> is possible, it is not recommended. So, user needs to decide from
> start of the day, which driver they want to use for MR-Fusion  card.
> |
> | -- Implementation details --
> | To support this feature, we have modify <mfi> code to change default
> return type from probe. Currently <mfi> driver return
> "BUS_PROBE_DEFAULT". <mfi> driver has been be changed to return
> "BUS_PROBE_LOW_PRIORITY" if fusion_force hint from device.hints  is set.
> | Please notice, above mentioned implementation in <mfi> driver is only
> applicable in case of  MR-Fusion controller detection. For any other
> controllers, supported by <mfi> driver, the behavior of probe return will
> remain same as before.
> |
> |
> | -- High level feature list of <mrsas> -- 1. Supports Fast Path feature
> | of LSI controllers.
> | 2. Supports 4K sector Drives.
> | 3. CAM layer based interface. All VDs will be attached to CAM layer
> | (Expected storage will be visible in "camcontroll") 4. Complete
> | support of Online Controller Reset. (OCR) 5.  OCR on Fimrware fault and IO
> timeout case.
> | 6. Work well with <storcli> management application which is generic
> application provided by LSI for all other Operating system.
> | 7. Supporst DIF enabled VDs (Same support as provided in Linux and
> | other OSes in FreeBSD) 8. Fast Path Load balance support.
> |
> | - In summary, this driver is in part with Linux based MR drivers and
> | all other features will be available to <mrsas> as planned activity
> | from LSI
> |
> | This code is well tested by LSI Q/A team on 32 bit and 64 bit FreeBSD
> Released OSes.
> 
> Sorry it is has taken so long to start playing with this.  I found one critical issue
> with read performance.  I added a printf to the driver to make sure the fast
> path is not being used and it claims it isn't.
> Doing either a dd or using the
> dt(http://www.scsifaq.org/RMiller_Tools/dt.html)
> I see good write performance with both mrsas and mfi but on read mrsas is
> backing up and appears to be single threaded.  With mrsas doing a dd
> of=/dev/zero if=/dev/da0 bs=1m I'm seeing 45685 kBps and with mfi seeing
> 597072 kBps via gstat.  Using dt via:
> 	dt of=/dev/da0 bs=64k limit=1g aios=32
> I see writes at 538977 Kbytes/sec and reads at bouncing around between
> 20000 - 8000 Kbytes/sec, mfi reports 244744 Kbytes/sec.  The interesting
> piece is seeing the L(q) via gstat being around 30 when doing mrsas reads,
> writes are 1 or less.  With mfi both read and writes are 1 or less.
> 
Thanks for for providing feedback. This is very important observation. We will work on this and get back to you.  Meanwhile, if we have high  level acceptance(considering few defect fixes and optimization as a follow up activity) of current <mrsas> code, can have <mrsas> commit in current FreeBSD driver. This will definitely help us to manage source code from single destination. Currently there are multiple flavors/version of <mrsas> driver code is floated due to Upstream commit is pending. We can work for each observation/optimization proposed from upstream community on priority bases.

> This is with a GENERIC kernel on -current/amd64.  I updated my source to
> 260231 and see the same.  Witness, etc. are all on.  I don't recall seeing this
> when I tested mrsas a long time ago.

Thanks for additional info.

> 
> The card I'm using is:
>   LSI MegaRAID SAS 9266-8i
>   Firmware BIOS 5.38.00_4.12.05.00_0x05180000
>   Firmware BCON 6.1-49-e_49-Rel
>   Firmware PCLI 05.05-03:#%00011
>   Firmware APP  3.220.75-2196
>   Firmware NVDT 2.1209.03-0117
>   Firmware BTBL 2.05.00.00-0010
>   Firmware BOOT 07.26.13.219
> 
> Some other issues I ran into when I kldunload mrsas I got a:
> 	sysctl_unregister_oid: failed to unregister sysctl and then when I

I do not recall if we have seen this issue, but will try this on our setup.

> kldload mrsas I got a panic:
> mrsas0: <LSI Thunderbolt SAS Controller> port 0x7000-0x70ff mem
> 0xdf060000-0xdf0 63fff,0xdf000000-0xdf03ffff irq 32 at device 0.0 on pci4
> #########################################################
> <mrsas> Driver has detected MR-Fusion Controller.If you wish to switch to
> <mfi> driver for MR-Fusion,read manual of mrsas. Once you chose to use
> <mrsas> Driverf or MR-Fusion Controllers, you should not switch to <mfi>.LSI
> recommend to use <m
> rsas> driver for MR-Fusion.Use <mrsas> if you are not sure about
> rsas> choice.Quick he
> lp to use <mfi> for MR-Fustion Card:
>  Remove hint.mrsas.0.fusion_force=1 from /boot/device.hints.
> #########################################################
> mrsas0: Waiting for FW to come to ready state
> 
> <panic message from malloc>
> 
> db> tr
> Tracing pid 534 tid 100245 td 0xfffff80015035490
> malloc() at malloc+0x1c8/frame 0xfffffe03fbab3200
> cpuctl_devs() at cpuctl_devs+0x61df/frame 0xfffffe03fbab3290
> cpuctl_devs() at cpuctl_devs+0x6189/frame 0xfffffe03fbab32f0
> cpuctl_devs() at cpuctl_devs+0x990a/frame 0xfffffe03fbab34b0
> device_attach() at device_attach+0x3a2/frame 0xfffffe03fbab3510
> pci_driver_added() at pci_driver_added+0xfa/frame 0xfffffe03fbab3550
> devclass_driver_added() at devclass_driver_added+0x7d/frame
> 0xfffffe03fbab3590
> devclass_add_driver() at devclass_add_driver+0x127/frame
> 0xfffffe03fbab35d0
> module_register_init() at module_register_init+0xb0/frame
> 0xfffffe03fbab3600
> linker_load_module() at linker_load_module+0xbda/frame
> 0xfffffe03fbab3930
> kern_kldload() at kern_kldload+0xad/frame 0xfffffe03fbab3970
> sys_kldload() at sys_kldload+0x5b/frame 0xfffffe03fbab39a0
> amd64_syscall() at amd64_syscall+0x265/frame 0xfffffe03fbab3ab0
> Xfast_syscall() at Xfast_syscall+0xfb/frame 0xfffffe03fbab3ab0
> 
> I played with storcli/storcli64 and MegaCli/MegaCli64 from LSI's web site.
> I noticed that the 32 bit versions are built for FreeBSD 8.1 and the 64 bit
> FreeBSD 7.4.  It might not be a critical problem but some companies might still
> be on earlier releases.
> 
> I need to look at adding the ioctl translation support for mfiutil and Linux to
> mrsas.  This means we should have a 32 bit to 64 bit ioctl translator in the
> driver since our Linux emulation is 32 bit.
We can pick this work as next action item.

> It's also handy to run 32 bit tools on the 64 bit kernel.
> 
> It would be good to add alias support for /dev/mfid* such as was done via
> ATA CAM sys/cam/ata/ata_da.c.  Search for ada_legacy_aliases and
> legacy_id.  The helped the migration from /dev/ad* to /dev/ada*.
> 
Let me check this. You can help me to understand what is expected here and we can provide solution for this.
Again, we can mark this as next to-do for mrsas and will provide patch as an when we have code ready.

> I'm not sure hint.mrsas.<x>.fusion_force="1" is a good toggle to
> enable/disable mrsas.  I can see why you did that but it might be more
> obvious to make hint.mfi.<x>.disabled="1" to work since that follows more
> of what people are used to.
Either way is fine, since hint.mfi.<X>.disabled may miss lead that we are going to disable <mfi> completely.
We may have <mfi> driver working for Falcon and other old MFI based controllers.

> 
> Thanks,
> 
> Doug A.