with spl used to protect other allocations and frees, or datastructure
element insertion and removal, in adjacent code.
It is almost unquestionably the case that some of the spl()/splx() calls
added here are superfluous, but it really seems wrong to see:
s=splfoo();
/* frob data structure */
splx(s);
pool_put(x);
and if we think we need to protect the first operation, then it is hard
to see why we should not think we need to protect the next. "Better
safe than sorry".
It is also almost unquestionably the case that I missed some pool
gets/puts from interrupt context with my strategy for finding these
calls; use of PR_NOWAIT is a strong hint that a pool may be used from
interrupt context but many callers in the kernel pass a "can wait/can't
wait" flag down such that my searches might not have found them. One
notable area that needs to be looked at is pf.
See also:
http://mail-index.netbsd.org/tech-kern/2006/07/19/0003.htmlhttp://mail-index.netbsd.org/tech-kern/2006/07/19/0009.html
"private" structure in struct buf that can be used to keep track of
the request associated with this buffer (the buffer used here is one
allocated from rf_CreateDiskQueueData(), so it's ours to do with what
we please). Shrinks code a little, reduces the run-time memory
footprint a bit, and simplifies both rf_DispatchKernelIO() and
KernelWakeupFunc().
Thanks to yamt for his "why is rf_DispatchKernelIO using another buf"
question which prompted me to revisit this code.
Commit fixes problem reported (privately) by Jeff Rizzo.
XXX: Note that we are still are unable to allow a reconstruct of
a failed spare -- it's easy enough to attempt to do it, but the
code in rf_ContinueReconstructFailedDisk() isn't anywhere close to
ready to allow it. Yet another reason why the whole disk/spare thing
needs to be re-worked. *sigh*
- rather than embedding bufq_state in driver softc,
have a pointer to the former.
- move bufq related functions from kern/subr_disk.c to kern/subr_bufq.c.
- rename method to strategy for consistency.
- move some definitions which don't need to be exposed to the rest of kernel
from sys/bufq.h to sys/bufq_impl.h.
(is it better to move it to kern/ or somewhere?)
- fix some obvious breakage in dev/qbus/ts.c. (not tested)
- introduce rf_buf_queue_check() which checks to see if there
is work to do in the incoming buffer queue
- rf_RaidIOThread() is now responsible for calling raidstart(), and is
also now the only place that calls raidstart()
- raidstrategy() now just queues requests in buf_queue
and signals rf_RaidIOThread() that work has arrived
Hopefully addresses PR#30233
render the RAID set completely dead. Instead, we retry the IO a
maximum of RF_RETRY_THRESHOLD times (currently '5'), and then just
return an IO error if the IO fails. This should reduce the damage
caused by having multiple disks appear to fail when the culprit is
really something else (power, controllers, etc.)
- If DIOCGDINFO failed with ENOTTY, don't print an error message; wedges
don't support that ioctl. Clean up the error message.
- If DIOCGDINFO fails, don't proceed to examine an invalid disklabel
structure.
As well, when we do detect some sort of an error, we should be doing a
biodone() here. Thanks to yamt for noting the missing biodone(), as
that led to discovery of the additional lossage.
by RAIDframe. Convert all other RAIDframe global pools to use pools
defined within this new structure.
- Introduce rf_pool_init(), used for initializing a single pool in
RAIDframe. Teach each of the configuration routines to use
rf_pool_init().
- Cleanup a few pool-related comments.
- Cleanup revent initialization and #defines.
- Add a missing pool_destroy() for the reconbuffer pool.
(Saves another 1K off of an i386 GENERIC kernel, and makes
stuff a lot more readable)
by RAIDframe. Convert all other RAIDframe global pools to use pools
defined within this new structure.
- Introduce rf_pool_init(), used for initializing a single pool in
RAIDframe. Teach each of the configuration routines to use
rf_pool_init().
- Cleanup a few pool-related comments.
- Cleanup revent initialization and #defines.
- Add a missing pool_destroy() for the reconbuffer pool.
(Saves another 1K off of an i386 GENERIC kernel, and makes
stuff a lot more readable)
- introduce RF_MIN_*'s, as necessary. These will indicate the
low-water mark for pools as well as the pool_prime() value.
- add pool_setlowat() for the critical pools.
- pool_prime() and pool_setlowat() the raidframe_cbufpool.
- re-order some pool_prime()'s and pool_sethiwat()'s for clarity.
VOP_STRATEGY(bp) is replaced by one of two new functions:
- VOP_STRATEGY(vp, bp) Call the strategy routine of vp for bp.
- DEV_STRATEGY(bp) Call the d_strategy routine of bp->b_dev for bp.
DEV_STRATEGY(bp) is used only for block-to-block device situations.
christos