Until now, the async append interface has required async_append_enable()
to be called while the process was still single-threaded, with the
rationale being that async_append_enable() could race with
async_append_write() on some existing async_append object. This was a
difficult problem when the async append interface was introduced, because
at the time Open vSwitch did not have any infrastructure for inter-thread
synchronization.
Now it is easy to solve, by introducing synchronization into the
async append module. However, that's more or less wasted, because the
client is already required to serialize access to async append objects.
Moreover, vlog, the only existing client, needs to serialize access for
other reasons, so it wouldn't even be possible to just drop the client's
synchronization.
This commit therefore takes another approach. It drops the
async_append_enable() interface entirely. Now any existing async_append
object is always enabled. The responsibility for "enabling", then, now
rests in whether the client creates and uses an async_append object, and
so vlog now takes care of that by itself. Also, since vlog now has to
deal with sometimes having an async_append and sometimes not having one,
we might as well allow creating an async_append to fail, thereby slightly
simplifying the "no async I/O" implementation from "write synchronously"
to "always fail creating an async_append".
Reported-by: Shih-Hao Li <shihli@nicira.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
This commit adds annotations for thread safety check. And the
check can be conducted by using -Wthread-safety flag in clang.
Co-authored-by: Alex Wang <alexw@nicira.com>
Signed-off-by: Alex Wang <alexw@nicira.com>
Signed-off-by: Ethan Jackson <ethan@nicira.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
Prepend "ovs|" to syslog logs to make them easier to filter out of all
LOG_DAEMON logs.
Signed-off-by: Romain Lenglet <rlenglet@vmware.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
Two of the users of vlog_set_levels_from_string() in the tests could have
silently failed, if their arguments were invalid. This avoids that problem
(and a memory leak).
Found by Coverity.
Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Ethan Jackson <ethan@nicira.com>
A few times while troubleshooting it would have been useful to get
complete logs, rather than post-rate-limiting snapshots of them. These
ovs-appctl commands make that possible.
Signed-off-by: Ben Pfaff <blp@nicira.com>
Whereas VLOG_FATAL() eventually calls exit(1), VLOG_ABORT()
eventually calls abort(). The key difference is that abort()
will cause a "monitor" process to restart, where exit(1) will
cause it to exit along with the monitored process.
Signed-off-by: Ben Pfaff <blp@nicira.com>
This will be more useful later when we introduces "worker" subprocesses.
I don't have any current plans to introduce threading, but I can't
think of a disadvantage to wording this in a general manner.
Signed-off-by: Ben Pfaff <blp@nicira.com>
This commit converts two rate-limiters in the tree to use the library.
I intend to use the library elsewhere in the future.
Signed-off-by: Ben Pfaff <blp@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>
Change the default timestamp for console and file logs to
UTC in a format that satisfies timestamp requirements in RFC 5424.
Also, add the ability for ovs-appctl to log timestamps in UTC.
Bug #9052.
Signed-off-by: Gurucharan Shetty <gshetty@nicira.com>
Users should be able to find out what a log level means without reading
source code comments, so this seems like a better place for it.
Reported-by: David Tsai <dtsai@nicira.com>
Until now, "emer" has effectively been "off" because no messages were ever
logged at "emer" level. Justin points out that it is useful to use "emer"
for messages that indicate a fatal error. This commit makes that change
and adds a new "off" level to really turn off all logging to a facility.
When a message is suppressed by vlog ratelimiting, and then that message
occurs again much later, sometimes we get messages like this:
Dropped 4 log messages in last 8695 seconds due to excessive rate
It seems pretty clear in this case that in fact we just didn't get that
kind of message for most of that 8695 seconds. This commit improves the
message by adding a little more detail, e.g.:
Dropped 4 log messages in last 8695 seconds (most recently, 6697 seconds
ago) due to excessive rate.
Bug #2144.
sparse warns if a non-static variable with external linkage has an
initializer at first declaration, because it suspects that it should be
static instead. Generally it's correct, but not in these cases, so add
a redundant declaration to suppress the warning.
The suppress warnings look like:
../ofproto/connmgr.c:40:1: warning: symbol 'VLM_connmgr' was not declared. Should it be static?
../ofproto/collectors.c:31:1: warning: symbol 'vlog_module_ptr_collectors' was not declared. Should it be static?
../ofproto/connmgr.c:43:1: warning: symbol 'counter_ofconn_stuck' was not declared. Should it be static?
These macros expanded the LEVEL argument without protecting it with
parentheses, which meant that an argument like 'cond ? VLL_DBG : VLL_WARN'
did not have the desired effect (and caused a GCC warning).
This commit fixes the problem and avoids expanding LEVEL more than once,
too.
Until now, the collection of vlog modules supported by a given OVS program
was not specific to that program. That means that, for example, even
though ovs-dpctl does not have anything to do with jsonrpc, it still has
a vlog module for it. This is confusing, at best.
This commit fixes the problem on some systems, in particular on ones that
use GCC and the GNU linker. It uses the feature of the GNU linker
described in its manual as:
If an orphaned section's name is representable as a C identifier then
the linker will automatically see PROVIDE two symbols: __start_SECNAME
and __end_SECNAME, where SECNAME is the name of the section. These
indicate the start address and end address of the orphaned section
respectively.
Systems that don't support these features retain the earlier behavior.
This commit also fixes the annoyance that modifying lib/vlog-modules.def
causes all sources files that #include "vlog.h" to recompile.
Adding a macro to define the vlog module in use adds a level of
indirection, which makes it easier to change how the vlog module must be
defined. A followup commit needs to do that, so getting these widespread
changes out of the way first should make that commit easier to review.
