bridge: Reconfigure in single pass.

This greatly simplifies the reconfiguration code, making it much easier
to understand and modify.  The old multi-pass configuration had the
property that it didn't delay block packet processing as much, but that's
not much of a worry anymore now that latency critical activities have
been moved outside the main thread.

Signed-off-by: Ben Pfaff <blp@nicira.com>
bridge: Support changing port numbers.

Feature #21293.
Requested-by: Anuprem Chalvadi <achalvadi@vmware.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
lib/util: More portable use of builtin popcnt.

- Use the GCC predefined macro __POPCNT__ to detect the availability
  of fast __builtin_popcnt function.
- Use portable preprocessor macros to detect 64-bit build.
- Only define the 32-bit parts when needed and declare the
  count_1bits_8 at file scope to silence a warning.

This time I have tested all code paths to make sure no warnigns are
generated.

Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com>
Reviewed-by: Simon Horman <horms@verge.net.au>
ofproto-dpif: Remove dead code.

Signed-off-by: Ethan Jackson <ethan@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
ofproto: Remove arbitrary handler thread limit.

There's no particular reason to limit the number of handler threads to
64.  If someone wants to try more, let them.

Signed-off-by: Ethan Jackson <ethan@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
netdev: Globally track port status changes

Previously, we tracked status changes for ofports on a per-device basis.
Each time in the main thread's loop, we would inspect every ofport
to determine whether the status had changed for corresponding devices.

This patch replaces the per-netdev change_seq with a global 'struct seq'
which tracks status change for all ports. In the average case where
ports are not constantly going up or down, this allows us to check the
sequence once per main loop and not poll any ports. In the worst case,
execution is expected to be similar to how it is currently.

In a test environment of 5000 internal ports and 50 tunnel ports with
bfd, this reduces average CPU usage of the main thread from about 40% to
about 35%.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Signed-off-by: Ethan Jackson <ethan@nicira.com>
Acked-by: Ethan Jackson <ethan@nicira.com>
ofproto-dpif: Don't poll ports when nothing changes

Previously, as part of ofproto-dpif run() processing, we would loop
through all ports and poll for changes to carrier, bfd, cfm and lacp
status. This information is used to determine whether bundles may be
enabled, and to perform revalidation when needed.

This patch makes the bfd, cfm, lacp and stp modules aware of the new
global connectivity_seq, notifying on changes in port status. We can
then use connectivity_seq to check if anything has changed before
looping through all ports in ofproto-dpif. In a test environment of 5000
internal ports and 50 tunnel ports with bfd, this reduces average CPU
usage of the main thread from about 35% to about 25%.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Signed-off-by: Ethan Jackson <ethan@nicira.com>
Acked-by: Ethan Jackson <ethan@nicira.com>
bridge: Only store instant_stats on device changes

Previously, we iterated through all interfaces in instant_stats_run(),
grabbing up-to-date information about device and port status. After
assembling all of this information for all interfaces, we would
determine whether anything changed and only send an update to
ovsdb-server if something changed.

This patch uses the new global connectivity_seq to determine whether
there have been any changes before polling all interfaces, which reduces
unnecessary processing in the average case. In a test environment of
5000 internal ports and 50 tunnel ports with bfd, this reduces average
CPU usage of the main thread from about 15% to about 5%. When ports
change status more often than every 100ms, CPU usage is expected to
increase to previous rates.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Signed-off-by: Ethan Jackson <ethan@nicira.com>
Acked-by: Ethan Jackson <ethan@nicira.com>
ovs-dev.py: Build with both GCC and Clang.

Many deployments prefer to use gcc in production and it supports
sparse, while clang supports thread safety analysis and has
more/better warnings and error messages.  This patch changes
ovs-dev.py to build with both so that developers are unlikely to miss
something that one or the other could catch.

Signed-off-by: Ethan Jackson <ethan@nicira.com>
Acked-by: Joe Stringer <joestringer@nicira.com>