When we change system clock to years ago, a certain CPU may use up 100% cputime.
The reason is that in function virEventPollCalculateTimeout(), we assign the
unsigned long long result to an INT variable,
*timeout = then - now; // timeout is INT, and then/now are long long
if (*timeout < 0)
*timeout = 0;
there's a chance that variable @then minus variable @now may be a very large number
that overflows INT value expression, then *timeout will be negative and be assigned to 0.
Next the 'poll' in function virEventPollRunOnce() will get into an 'endless' while loop there.
thus, the cpu that virEventPollRunOnce() thread runs on will go up to 100%.
Although as we discussed before in https://www.redhat.com/archives/libvir-list/2015-May/msg00400.html
it should be prohibited to set-time while other applications are running, but it does
seems to have no harm to make the codes more robust.
Signed-off-by: Wang Yufei <james.wangyufei@huawei.com>
Signed-off-by: Zhang Bo <oscar.zhangbo@huawei.com>
When dispatching events from the event loop, the array of registered
handles is searched to see what handles happened an event on. However,
the array is searched in weird way: the check for the array boundaries
is at the end, so we may touch the elements after the end of the
array:
==10434== Invalid read of size 4
==10434== at 0x52D06B6: virEventPollDispatchHandles (vireventpoll.c:486)
==10434== by 0x52D10E4: virEventPollRunOnce (vireventpoll.c:660)
==10434== by 0x52CF207: virEventRunDefaultImpl (virevent.c:308)
==10434== by 0x1639D1: virNetServerRun (virnetserver.c:1139)
==10434== by 0x1220DC: main (libvirtd.c:1507)
==10434== Address 0xc11ff04 is 4 bytes after a block of size 960 alloc'd
==10434== at 0x4C2CA5E: realloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==10434== by 0x52AD378: virReallocN (viralloc.c:245)
==10434== by 0x52AD46E: virExpandN (viralloc.c:294)
==10434== by 0x52AD5B1: virResizeN (viralloc.c:352)
==10434== by 0x52CF2EC: virEventPollAddHandle (vireventpoll.c:116)
==10434== by 0x52CEF5B: virEventAddHandle (virevent.c:78)
==10434== by 0x11F69A90: nodeStateInitialize (node_device_udev.c:1797)
==10434== by 0x53C3C89: virStateInitialize (libvirt.c:743)
==10434== by 0x120563: daemonRunStateInit (libvirtd.c:919)
==10434== by 0x5317719: virThreadHelper (virthread.c:197)
==10434== by 0x8376F39: start_thread (in /lib64/libpthread-2.17.so)
==10434== by 0x8A7F9FC: clone (in /lib64/libc-2.17.so)
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Any source file which calls the logging APIs now needs
to have a VIR_LOG_INIT("source.name") declaration at
the start of the file. This provides a static variable
of the virLogSource type.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The dtrace probe macros rely on the logging API. We can't make
the internal.h header include the virlog.h header though since
that'd be a circular include. Instead simply split the dtrace
probes into their own header file, since there's no compelling
reason for them to be in the main internal.h header.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The debug message said there was a timeout of 0 pending for -1 ms which
made me think this is where a hang was coming from but according to the
function comments this case means that there is no timeout pending so
make the debug message say that instead of saying there's a -1 ms
timeout.
Convert the type of loop iterators named 'i', 'j', k',
'ii', 'jj', 'kk', to be 'size_t' instead of 'int' or
'unsigned int', also santizing 'ii', 'jj', 'kk' to use
the normal 'i', 'j', 'k' naming
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
POSIX says pthread_t is opaque. We can't guarantee if it is scaler
or a pointer, nor what size it is; and BSD differs from Linux.
We've also had reports of gcc complaining on attempts to cast it,
if we use a cast to the wrong type (for example, pointers have to be
cast to void* or intptr_t before being narrowed; while casting a
function return of scalar pthread_t to void* triggers a different
warning).
Give up on casts, and use unions to get at decent bits instead. And
rather than futz around with figuring which 32 bits of a potentially
64-bit pointer are most likely to be unique, convert the rest of
the code base to use 64-bit values when using a debug id.
Based on a report by Guido Günther against kFreeBSD, but with a
fix that doesn't regress commit 4d970fd29 for FreeBSD.
* src/util/virthreadpthread.c (virThreadSelfID, virThreadID): Use
union to get at a decent bit representation of thread_t bits.
* src/util/virthread.h (virThreadSelfID, virThreadID): Alter
signature.
* src/util/virthreadwin32.c (virThreadSelfID, virThreadID):
Likewise.
* src/qemu/qemu_domain.h (qemuDomainJobObj): Alter type of owner.
* src/qemu/qemu_domain.c (qemuDomainObjTransferJob)
(qemuDomainObjSetJobPhase, qemuDomainObjReleaseAsyncJob)
(qemuDomainObjBeginNestedJob, qemuDomainObjBeginJobInternal): Fix
clients.
* src/util/virlog.c (virLogFormatString): Likewise.
* src/util/vireventpoll.c (virEventPollInterruptLocked):
Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
