idl-loop is needed in implementing other controller (i.e., vtep controller).
So, this commit moves the logic into ovsdb-idl library module.
Signed-off-by: Alex Wang <alexw@nicira.com>
Acked-by: Russell Bryant <rbryant@redhat.com>
We've had this question a couple of times so we might as well document it.
Requested-by: Saurabh Shrivastava (सौरभ श्रीवास्तव) <saurabh@gmail.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
The following macros are renamed to avoid conflicts with other headers:
* WARN_UNUSED_RESULT to OVS_WARN_UNUSED_RESULT
* PRINTF_FORMAT to OVS_PRINTF_FORMAT
* NO_RETURN to OVS_NO_RETURN
Signed-off-by: Thomas Graf <tgraf@noironetworks.com>
Acked-by: Ben Pfaff <blp@nicira.com>
OVSDB has the concept of "immutable" columns, which are columns whose
values are fixed once a row is inserted. Until now, ovs-vsctl has not
allowed these columns to be modified at all. However, this is a little too
strict, because these columns can be set to any value at the time that the
row is inserted. This commit relaxes the ovs-vsctl requirement, then, to
allow an immutable column's value to be modified if its row has been
inserted within this transaction.
Requested-by: Mukesh Hira <mhira@vmware.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
If ovs-vsctl has to wait for ovs-vswitchd to reconfigure itself
according to the new database, then sometimes ovs-vsctl could
end up stuck in the event loop if OVSDB connection was dropped
while ovs-vsctl was still running.
This patch fixes this problem by letting ovs-vsctl to reconnect
to the OVSDB, if it has to wait cur_cfg field to be updated.
Issue: 1191997
Reported-by: Spiro Kourtessis <spiro@nicira.com>
Signed-Off-By: Ansis Atteka <aatteka@nicira.com>
Until now, ovs-vsctl has kept trying to the database server until it
succeeded or the timeout expired (if one was specified with --timeout).
This meant that if ovsdb-server wasn't running, then ovs-vsctl would hang.
The result was that almost every ovs-vsctl invocation in scripts specified
a timeout on the off-chance that the database server might not be running.
But it's difficult to choose a good timeout. A timeout that is too short
can cause spurious failures. A timeout that is too long causes long delays
if the server really isn't running.
This commit should alleviate this problem. It changes ovs-vsctl's behavior
so that, if it fails to connect to the server, it exits unsuccessfully.
This makes --timeout obsolete for the purpose of avoiding a hang if the
database server isn't running. (--timeout is still useful to avoid a hang
if ovsdb-server is running but ovs-vswitchd is not, for ovs-vsctl commands
that modify the database. --no-wait also avoids that issue.)
Bug #2393.
Bug #15594.
Reported-by: Jeff Merrick <jmerrick@vmware.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
For 1000 tunnels with CFM enabled, this reduces CPU use from
about 36% to about 30%.
Bug #15171.
Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Ethan Jackson <ethan@nicira.com>
ovs-vswitchd should only write to write-only columns. Furthermore,
writing to a column which is not write-only can cause serious
performance degradations. This patch causes ovs-vswitchd to log
and reject writes to read-write columns.
Signed-off-by: Ethan Jackson <ethan@nicira.com>
Replaced all instances of Nicira Networks(, Inc) to Nicira, Inc.
Feature #10593
Signed-off-by: Raju Subramanian <rsubramanian@nicira.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
Originally the IDL transaction state machine had a return value
TXN_TRY_AGAIN to signal the client to wait for a change in the database and
then retry its transaction. However, this logic was incomplete, because
it was possible for the database to change before the reply to the
transaction RPC was received, in which case the client would wait for a
further change. Commit 4fdfe5ccf84c (ovsdb-idl: Prevent occasional hang
when multiple database clients race.) fixed the problem by breaking
TXN_TRY_AGAIN into two status codes, TXN_AGAIN_WAIT that meant to wait for
a further change and TXN_AGAIN_NOW that meant that a change had already
occurred so try again immediately.
This is correct enough, but it is more complicated than necessary. It is
simpler and just as correct to use a single "try again" status that
requires the client to wait for a change relative to the database contents
*before* the transaction was committed. This commit makes that change.
It also changes ovsdb_idl_run()'s return type from bool to void because
its return type is hardly useful anymore.
Signed-off-by: Ben Pfaff <blp@nicira.com>
When a client of the IDL tries to commit a read-modify-write transaction
but the database has changed in the meantime, the IDL tells its client to
wait for the IDL to change and then try the transaction again by returning
TXN_TRY_AGAIN. The "wait for the IDL to change" part is important because
there's no point in retrying the transaction before the IDL has received
the database updates (the transaction would fail in the same way all over
again).
However, the logic was incomplete: the database update can be received
*before* the reply to the transaction RPC (I think that in the current
ovsdb-server implementation this will always happen, in fact). When this
happens, the right thing to do is to retry the transaction immediately;
if we wait, then we're waiting for an additional change to the database
that may never come, causing an indefinite hang.
This commit therefore breaks the "try again" IDL commit status code
into two, one that means "try again immediately" and another that means
"wait for a change then try again". When an update is processed after a
transaction is committed but before the reply is received, the "try again
now" tells the IDL client not to wait for another database change before
retrying its transaction.
Bug #5980.
Reported-by: Ram Jothikumar <rjothikumar@nicira.com>
Reproduced-by: Alex Yip <alex@nicira.com>
Once in a while someone reports a problem caused by running multiple
ovs-vswitchd processes at the same time. This fixes the problem by
requiring ovs-vswitchd to obtain a database lock before taking any actions.
The state machine didn't have a proper state for "not yet committed or
aborted", which meant that destroying an ovsdb_idl_txn without committing
or aborting it caused a segfault. This fixes the problem by adding a new
state TXN_UNCOMMITTED to the state machine.
This is related to commit 79554078d "ovsdb-idl: Fix bad logic in
ovsdb_idl_txn_commit() state transitions", which fixed a related bug.
Bug #2438.
Until now, ovs-vswitchd has been unable to configure IP addresses and
routes for bridges whose Bridge records lack a Port and an Interface
record for the bridge's local port (e.g. OFPP_LOCAL, the port with the
same name as the bridge itself). When such a bridge was reconfigured,
ovs-vswitchd would output a log message that worried people.
This commit fixes the internal limitation that led to the message being
printed.
Bug #5385.
Until now, by default the IDL replicated all tables and all columns in the
database, and a few functions made it possible to avoid replicating
selected columns. This commit adds a mode in which nothing is replicated
by default and the client code is responsible for specifying each column
and table that it is interested in. The following commit adds a user for
this mode.
ovs-vswitchd has no need to replicate some parts of the database. In
particular, it doesn't need to replicate the bits that it never reads,
such as the external_ids column in the Open_vSwitch table. This saves
some memory, CPU time, and bandwidth to the database.
Another type of column that benefits from special treatment is "write-only
columns", that is, those that ovs-vswitchd writes and keeps up-to-date but
never expects another client to write, such as the cur_cfg column in the
Open_vSwitch table. If the IDL reports that the database has changed when
ovs-vswitchd updates such a column, then ovs-vswitchd reconfigures itself
for no reason, wasting CPU time. This commit also adds support for such
columns.
The existing ovsdb_idl_txn_read() was somewhat difficult and expensive to
use, because it always made a copy of the data in the column. This was
necessary at the time it was introduced, because there was no way for it
to return a "default" value for columns that had not yet been populated
without allocating data and hence requiring the caller to free it.
Now that ovsdb_datum_default() exists, this is no longer required. This
commit introduces a pair of new functions, ovsdb_idl_read() and
ovsdb_idl_get(), that return a pointer to existing data and do not do any
copying. It also transitions all of ovsdb_idl_txn_read()'s callers to
the new interfaces.
This makes it easy to create a bunch of records that are all related to
each other in a single ovs-vsctl invocation. It adds an example to the
ovs-vsctl manpage.
Before OVSDB was adopted in the vswitch, bridge ioctls were synchronous.
That is, an operation that, say, creates a new bridge was guaranteed to
have completed before brcompatd returned a success result to the kernel.
When OVSDB was adopted, however, we failed to maintain this property.
Instead, bridge creation (etc.) only happened some time after the return
value was passed back to the kernel. This causes a race condition against
software that creates or deletes bridges or ports and expects that the
operation is completed synchronously.
This commit restores the synchronous behavior.
Bug #2443.
The ovs-vsctl "create" command, and perhaps other commands, should print
the UUID of the newly created database row, but until now the IDL has not
provided a way to find that out. This commit adds the ability.
ovs-vsctl wants to use these functions directly, so make them available
through the ovsdb-idl public header instead of only through the private
one.
Also, change the prototypes to make them usable without casts.
The IDL is intended to allow clients easier access to data in the database
by providing an extra layer of abstraction. However, ovs-vsctl needs to
also provide generic access to database tables, rows, and columns, and
until now the IDL has not allowed this. In particular, there was no way
to modify the value of a database column by providing a "struct
ovsdb_datum" with the new value and then have that reflected in the IDL
structs, although the other direction was possible.
This commit fixes that problem, which requires a bit of refactoring of the
IDL layer. It also exposes the interface for iterating through table
records to clients directly, by moving it from the "private" IDL header to
the public one.
Until now the ovsdb-based vswitch has provided no way to know when it has
finished applying the configuration from the database. This commit
introduces a way:
* The client who wants to wait increments the "next_cfg" column of the
Open_vSwitch record.
* When ovs-vswitchd finishes reconfiguring, it sets the value of the
"cur_cfg" column to that of the "next_cfg" column.
* The client waits until the "cur_cfg" column is at least as great as
the value it set into "next_cfg".
This allows us to drop the 5-second sleep in interface-reconfigure.
The idea here is that transaction comments get copied to the ovsdb-server's
transaction log, which can then make it clear later why a particular change
was made to the database, to ease debugging.
