This last patch (but not least :) ) finally moves the next pointer at
the end of struct dst_entry. This permits to perform route cache
lookups with a minimal cost of one cache line per entry, instead of
two.
Both 32bits and 64bits platforms benefit from this new layout.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes the next pointer from 'struct dn_route.u' union,
and renames u.rt_next to u.dst.dn_next.
It also moves 'struct flowi' right after 'struct dst_entry' to prepare
speedup lookups.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes the next pointer from 'struct rt6_info.u' union,
and renames u.next to u.dst.rt6_next.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes the rt_next pointer from 'struct rtable.u' union,
and renames u.rt_next to u.dst_rt_next.
It also moves 'struct flowi' right after 'struct dst_entry' to prepare
the gain on lookups.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces an anonymous union to nicely express the fact that all
objects inherited from struct dst_entry should access to the generic 'next'
pointer but with appropriate type verification.
This patch is a prereq before following patches.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In a prior patch, I introduced a sk_hash field (__sk_common.skc_hash) to let
tcp lookups use one cache line per unmatched entry instead of two.
We can also use sk_hash to speedup UDP part as well. We store in sk_hash the
hnum value, and use sk->sk_hash (same cache line than 'next' pointer),
instead of inet->num (different cache line)
Note : We still have a false sharing problem for SMP machines, because
sock_hold(sock) dirties the cache line containing the 'next' pointer. Not
counting the udp_hash_lock rwlock. (did someone mentioned RCU ? :) )
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ATA_ENABLE_PATA define was never meant to be permanent, and in
recent kernels, it's already been unconditionally enabled. Remove.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
If we are doing a PIO setup for a CFA card and it blows up with a device
error then assume it is an older CFA card which doesn't support this
rather than failing the device out of existance.
Stands seperate to the quieting patch but that is obviously useful with
this change.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ata_pci_device_do_resume can fail if the PCI device couldn't be re-enabled.
Update sata_nv to propagate the return value from this call and to not try
to do any other resume activities if it fails. Fixes a compile warning.
Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Update sata_nv to wait for the controller to indicate via the status
register that it has entered the requested state when switching between
ADMA mode and register mode. This issue came up recently when debugging
some problems with cache flush command timeouts and while it didn't appear
to fix that problem, this is something we should likely be doing in any
case.
Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Some problems showed up recently with cache flush commands timing out on
sata_nv. Previously these commands were always handled by transitioning to
legacy mode from ADMA mode first. The timeout problem was worked around
already by a change to the interrupt handling code for legacy mode, but for
non-data commands like these it appears we can handle them in ADMA mode, so
the switch to legacy mode is not needed.
This patch changes the behavior so that we use ADMA mode to submit
interrupt-driven commands with ATA_PROT_NODATA protocol. In addition to
avoiding the problem mentioned above entirely, this avoids the overhead of
switching to legacy mode and back to ADMA mode for handling cache flushes.
When handling non-DMA-mapped commands, we leave the APRD blank and clear
the NV_CPB_CTL_APRD_VALID field in the CPB so the controller does not
attempt to read it.
Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This cleans up a few issues with the error handling in sata_nv in ADMA mode
to make it more consistent with other NCQ-capable drivers like ahci and
sata_sil24:
- When a command failed, we would effectively set AC_ERR_DEV on the
queued command always. In the case of NCQ commands this prevents libata
from doing a log page query to determine the details of the failed
command, since it thinks we've already analyzed. Just set flags in the
port ehi->err_mask, then freeze or abort and let libata figure out what
went wrong.
- The code handled NV_ADMA_STAT_CPBERR as a "really bad error" which
caused it to set error flags on every queued command. I don't know
exactly what this flag means (no docs, grr!) but from what I can guess
from the standard ADMA spec, it just means that one or more of the CPBs
had an error, so we just need to go through and do our normal checks in
this case.
- In the error_handler function the code would always dump the state of
all the CPBs. This output seems redundant at this point since libata
already dumps the state of all active commands on errors (and it also
triggers at times when it shouldn't, like when suspending). Take this
out.
[akpm@osdl.org: many coding-style fixes]
Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Allen Martin <AMartin@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
