This is kind of hokey, we could use the hardware provided facilities
much better.
MSIs are assosciated with MSI Queues. MSI Queues generate interrupts
when any MSI assosciated with it is signalled. This suggests a
two-tiered IRQ dispatch scheme:
MSI Queue interrupt --> queue interrupt handler
MSI dispatch --> driver interrupt handler
But we just get one-level under Linux currently. What I'd like to do
is possibly stick the IRQ actions into a per-MSI-Queue data structure,
and dispatch them form there, but the generic IRQ layer doesn't
provide a way to do that right now.
So, the current kludge is to "ACK" the interrupt by processing the
MSI Queue data structures and ACK'ing them, then we run the actual
handler like normal.
We are wasting a lot of useful information, for example the MSI data
and address are provided with ever MSI, as well as a system tick if
available. If we could pass this into the IRQ handler it could help
with certain things, in particular for PCI-Express error messages.
The MSI entries on sparc64 also tell you exactly which bus/device/fn
sent the MSI, which would be great for error handling when no
registered IRQ handler can service the interrupt.
We override the disable/enable IRQ chip methods in sun4v_msi, so we
have to call {mask,unmask}_msi_irq() directly from there. This is
another ugly wart.
Signed-off-by: David S. Miller <davem@davemloft.net>
Otherwise we can't use the generic MSI code.
Furthermore, properly use the {get,set}_irq_foo() abstracted
interfaces instead of direct accesses to irq_desc[]->foo.
Signed-off-by: David S. Miller <davem@davemloft.net>
Some partitioning systems create special partitions that
span the entire disk. One example are Sun partitions, and
this whole-disk partition exists to tell the firmware the
extent of the entire device so it can load the boot block
and do other things.
Such partitions should not be treated as normal partitions,
because all the other partitions overlap this whole-disk one.
So we'd see multiple instances of the same UUID etc. which
we do not want. udev and friends can thus search for this
'whole_disk' attribute and use it to decide to ignore the
partition.
Signed-off-by: Fabio Massimo Di Nitto <fabbione@ubuntu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I forgot to test build this part of the networking code... Sorry guys.
This patch renames u.rt_next to u.dst.rt_next
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It seems to miss RO mode path by IPv6 over IPv4 IPsec tunnel patch
when it changed semantics to check the mode from
"xfrm[i]->props.mode != XFRM_MODE_TRANSPORT" to
"xfrm[i]->props.mode == XFRM_MODE_TUNNEL" before changing address.
It also makes two incline functions __xfrm6_bundle_addr_{remote,local}
are used by nobody.
This patch fixes it.
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
