Modified the copyright year range in code, and corrected "int32_tel"
into "Intel" in two "hypervisor/include/debug/profiling.h" and
"hypervisor/include/debug/profiling_internal.h".
Tracked-On: #7559
Signed-off-by: Ziheng Li <ziheng.li@intel.com>
Commit d575edf79a changes the internal
implementation of wait_event and signal_event to use a counter instead
of a boolean value.
The background was:
ACRN utilizes vcpu_make_request and signal_event pair to shoot down
other vcpus and let them wait for signals. vcpu_make_request eventually
leads to target vcpu calling wait_event.
However vcpu_make_request/signal_event pair was not thread-safe,
and concurrent calls of this pair of API could lead to problems.
One such example is the concurrent wbinvd emulation, where vcpus may
concurrently issue vcpu_make_request/signal_event to synchronize wbinvd
emulation.
d575edf commit uses a counter in internal implementation of
wait_event/signal_event to avoid data races.
However by using a counter, the wait/signal pair now carries semantics of
semaphores instead of events. Semaphores require caller to carefully
plan their calls instead of multiply signaling any number of times to the same
event, which deviates from the original "event" semantics.
This patch changes the API implementation back to boolean-based, and
re-resolve the issue of concurrent wbinvd in next patch.
This also partially reverts commit 10963b04d1,
which was introduced because of the d575edf.
Tracked-On: #7887
Signed-off-by: Yifan Liu <yifan1.liu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
Many of the license and Intel copyright headers include the "All rights
reserved" string. It is not relevant in the context of the BSD-3-Clause
license that the code is released under. This patch removes those strings
throughout the code (hypervisor, devicemodel and misc).
Tracked-On: #7254
Signed-off-by: Geoffroy Van Cutsem <geoffroy.vancutsem@intel.com>
In lock instruction emulation, we use vcpu_make_request and
signal_event pairs to shoot down/release other vcpus.
However, vcpu_make_request is async and does not guarantee an execution
of wait_event on target vcpu, and we want wait_event to be consistent
with signal_event.
Consider following scenarios:
1, When target vcpu's state has not yet turned to VCPU_RUNNING,
vcpu_make_request on ACRN_REQUEST_SPLIT_LOCK does not make sense, and will
not result in wait_event.
2, When target vcpu is already requested on ACRN_REQUEST_SPLIT_LOCK (i.e., the
corresponding bit in pending_req is set) but not yet handled,
the vcpu_make_request call does not result in wait_event as 1 bit is not
enough to cache multiple requests.
This patch tries to add checks in vcpu_kick_lock_instr_emulation and
vcpu_complete_lock_instr_emulation to resolve these issues.
Tracked-On: #6502
Signed-off-by: Yifan Liu <yifan1.liu@intel.com>
Reviewed-by: Jason Chen CJ <jason.cj.chen@intel.com>
Because the emulation code is for both split-lock and uc-lock,
rename splitlock.c/splitlock.h to lock_instr_emul.c/lock_instr_emul.h
Tracked-On: #6299
Signed-off-by: Tao Yuhong <yuhong.tao@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
