src/sys/cam/cam_queue.h, branch releng/10.0FreeBSD source treehttps://cgit-dev.freebsd.org/src/atom?h=releng%2F10.02013-08-05T11:48:40ZMFprojects/camlock r249505:2013-08-05T11:48:40ZAlexander Motinmav@FreeBSD.org2013-08-05T11:48:40Zurn:sha1:ea541bfdaa5b2e2a893c8d76c67a43948947c7c5
Change CCB queue resize logic to be able safely handle overallocations:
- (re)allocate queue space in power of 2 chunks with 64 elements minimum
and never shrink it; with only 4/8 bytes per element size is insignificant.
- automatically reallocate the queue to double size if it is overflowed.
- if queue reallocation failed, store extra CCBs in unsorted TAILQ,
fetching them back as soon as some queue element is freed.
To free space in CCB for TAILQ linking, change highpowerq from keeping
high-power CCBs to keeping devices frozen due to high-power CCBs.
This encloses all pieces of queue resize logic inside of cam_queue.[ch],
removing some not obvious duties from xpt_release_ccb().
Remove some more pieces of multilevel freeze mechanism, missed in r249466.2013-04-14T18:09:08ZAlexander Motinmav@FreeBSD.org2013-04-14T18:09:08Zurn:sha1:1268d4813e88ad9eb1706237ab13cf9782124a81MFprojects/camlock r248890, r248897, r248898, r248900, r248903, r248905,2013-04-14T09:28:14ZAlexander Motinmav@FreeBSD.org2013-04-14T09:28:14Zurn:sha1:cccf422080e22281bbcb96e29128a89ce00cd4d4
r248917, r248918, r248978, r249001, r249014, r249030:
Remove multilevel freezing mechanism, implemented to handle specifics of
the ATA/SATA error recovery, when post-reset recovery commands should be
allocated when queues are already full of payload requests. Instead of
removing frozen CCBs with specified range of priorities from the queue
to provide free openings, use simple hack, allowing explicit CCBs over-
allocation for requests with priority higher (numerically lower) then
CAM_PRIORITY_OOB threshold.
Simplify CCB allocation logic by removing SIM-level allocation queue.
After that SIM-level queue manages only CCBs execution, while allocation
logic is localized within each single device.
Suggested by: gibbs
MFp4: Large set of CAM inprovements.2010-01-28T08:41:30ZAlexander Motinmav@FreeBSD.org2010-01-28T08:41:30Zurn:sha1:83c5d981ac176d1cfae8d6dab3c0420ed9d43477
- Unify bus reset/probe sequence. Whenever bus attached at boot or later,
CAM will automatically reset and scan it. It allows to remove duplicate
code from many drivers.
- Any bus, attached before CAM completed it's boot-time initialization,
will equally join to the process, delaying boot if needed.
- New kern.cam.boot_delay loader tunable should help controllers that
are still unable to register their buses in time (such as slow USB/
PCCard/ CardBus devices), by adding one more event to wait on boot.
- To allow synchronization between different CAM levels, concept of
requests priorities was extended. Priorities now split between several
"run levels". Device can be freezed at specified level, allowing higher
priority requests to pass. For example, no payload requests allowed,
until PMP driver enable port. ATA XPT negotiate transfer parameters,
periph driver configure caching and so on.
- Frozen requests are no more counted by request allocation scheduler.
It fixes deadlocks, when frozen low priority payload requests occupying
slots, required by higher levels to manage theit execution.
- Two last changes were holding proper ATA reinitialization and error
recovery implementation. Now it is done: SATA controllers and Port
Multipliers now implement automatic hot-plug and should correctly
recover from timeouts and bus resets.
- Improve SCSI error recovery for devices on buses without automatic sense
reporting, such as ATAPI or USB. For example, it allows CAM to wait, while
CD drive loads disk, instead of immediately return error status.
- Decapitalize diagnostic messages and make them more readable and sensible.
- Teach PMP driver to limit maximum speed on fan-out ports.
- Make boot wait for PMP scan completes, and make rescan more reliable.
- Fix pass driver, to return CCB to user level in case of error.
- Increase number of retries in cd driver, as device may return several UAs.
MFp4:2009-11-14T20:30:42ZAlexander Motinmav@FreeBSD.org2009-11-14T20:30:42Zurn:sha1:1f1158b28d08e72c5c25edbfd65275faf9664f50
Some more missed parts from previous commits.
After thinking again, implement cam_ccbq_fini().2009-10-22T21:07:32ZAlexander Motinmav@FreeBSD.org2009-10-22T21:07:32Zurn:sha1:20a7933f537f94048723ebea9e768dacc948aa7c
This is effectively NULL change, but makes this API a bit more consistent.
cam_ccbq_fini() declared for 11 years, but never implemented. Remove it.2009-10-22T20:44:55ZAlexander Motinmav@FreeBSD.org2009-10-22T20:44:55Zurn:sha1:ab593611be01418440cf828e3be863c32e2e48d3Start each of the license/copyright comments with /*-2005-01-05T22:34:37ZWarner Loshimp@FreeBSD.org2005-01-05T22:34:37Zurn:sha1:898b0535b73b62baaf1d386b169e4d215194a012Back out the previous change to the queue(3) interface.2000-05-26T02:09:24ZJake Burkholderjake@FreeBSD.org2000-05-26T02:09:24Zurn:sha1:e39756439c7255bc16ba14b7b991cb01ba1c93bd
It was not discussed and should probably not happen.
Requested by: msmith and others
Change the way that the queue(3) structures are declared; don't assume that2000-05-23T20:41:01ZJake Burkholderjake@FreeBSD.org2000-05-23T20:41:01Zurn:sha1:740a1973a62eaa8e1dc23e22f84dacb3346d303a
the type argument to *_HEAD and *_ENTRY is a struct.
Suggested by: phk
Reviewed by: phk
Approved by: mdodd