BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=1968
The new VS2012 build failure is caused by 7a0df26.
xxx\registercpufeatureslib\dxeregistercpufeatureslib.c(258) :
warning C4701: potentially uninitialized local variable 'MpEvent' used
It is a false positive alarm.
MpEvent is assigned at line 238 and will be used at line 258, both
lines are controlled by "if (CpuFeaturesData->NumberOfCpus > 1)".
This patch initializes MpEvent to suppress incorrect compiler/analyzer
warnings.
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Dandan Bi <dandan.bi@intel.com>
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
V3:
Define union to specify the ppi or protocol.
V2:
1. Initialize CpuFeaturesData->MpService in CpuInitDataInitialize
and make this function been called at the begin of the
initialization.
2. let all other functions use CpuFeaturesData->MpService install
of locate the protocol itself.
V1:
GetProcessorIndex function calls GetMpPpi to get the MP Ppi.
Ap will calls GetProcessorIndex function which final let AP calls
PeiService.
This patch avoid GetProcessorIndex call PeiService.
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=1411
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
V4 changes include:
1. Serial debug message for different threads when program the register table.
V3 changes include:
1. Use global variable instead of internal function to return string for register type
and dependence type.
2. Add comments for some complicated logic.
V2 changes include:
1. Add more description for the code part which need easy to understand.
2. Refine some code base on feedback for V1 changes.
V1 changes include:
In a system which has multiple cores, current set register value task costs huge times.
After investigation, current set MSR task costs most of the times. Current logic uses
SpinLock to let set MSR task as an single thread task for all cores. Because MSR has
scope attribute which may cause GP fault if multiple APs set MSR at the same time,
current logic use an easiest solution (use SpinLock) to avoid this issue, but it will
cost huge times.
In order to fix this performance issue, new solution will set MSRs base on their scope
attribute. After this, the SpinLock will not needed. Without SpinLock, new issue raised
which is caused by MSR dependence. For example, MSR A depends on MSR B which means MSR A
must been set after MSR B has been set. Also MSR B is package scope level and MSR A is
thread scope level. If system has multiple threads, Thread 1 needs to set the thread level
MSRs and thread 2 needs to set thread and package level MSRs. Set MSRs task for thread 1
and thread 2 like below:
Thread 1 Thread 2
MSR B N Y
MSR A Y Y
If driver don't control execute MSR order, for thread 1, it will execute MSR A first, but
at this time, MSR B not been executed yet by thread 2. system may trig exception at this
time.
In order to fix the above issue, driver introduces semaphore logic to control the MSR
execute sequence. For the above case, a semaphore will be add between MSR A and B for
all threads. Semaphore has scope info for it. The possible scope value is core or package.
For each thread, when it meets a semaphore during it set registers, it will 1) release
semaphore (+1) for each threads in this core or package(based on the scope info for this
semaphore) 2) acquire semaphore (-1) for all the threads in this core or package(based
on the scope info for this semaphore). With these two steps, driver can control MSR
sequence. Sample code logic like below:
//
// First increase semaphore count by 1 for processors in this package.
//
for (ProcessorIndex = 0; ProcessorIndex < PackageThreadsCount ; ProcessorIndex ++) {
LibReleaseSemaphore ((UINT32 *) &SemaphorePtr[PackageOffset + ProcessorIndex]);
}
//
// Second, check whether the count has reach the check number.
//
for (ProcessorIndex = 0; ProcessorIndex < ValidApCount; ProcessorIndex ++) {
LibWaitForSemaphore (&SemaphorePtr[ApOffset]);
}
Platform Requirement:
1. This change requires register MSR setting base on MSR scope info. If still register MSR
for all threads, exception may raised.
Known limitation:
1. Current CpuFeatures driver supports DXE instance and PEI instance. But semaphore logic
requires Aps execute in async mode which is not supported by PEI driver. So CpuFeature
PEI instance not works after this change. We plan to support async mode for PEI in phase
2 for this task.
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
V1 changes:
> Current code logic can't confirm CpuS3DataDxe driver start before
> CpuFeaturesDxe driver. So the assumption in CpuFeaturesDxe not valid.
> Add implementation for AllocateAcpiCpuData function to remove this
> assumption.
V2 changes:
> Because CpuS3Data memory will be copy to smram at SmmReadToLock point,
> so the memory type no need to be ACPI NVS type, also the address not
> limit to below 4G.
> This change remove the limit of ACPI NVS memory type and below 4G.
V3 changes:
> Remove function definition in header file.
> Add STATIC in function implementation.
Pass OS boot and resume from S3 test.
Bugz: https://bugzilla.tianocore.org/show_bug.cgi?id=959
Reported-by: Marvin Häuser <Marvin.Haeuser@outlook.com>
Suggested-by: Fan Jeff <vanjeff_919@hotmail.com>
Cc: Marvin Häuser <Marvin.Haeuser@outlook.com>
Cc: Fan Jeff <vanjeff_919@hotmail.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
PEI Register CPU Features Library instance is used to register/manager/program
CPU features on PEI phase.
DXE Register CPU Features Library instance is used to register/manager/program
CPU features on DXE phase.
v2:
Format debug messages.
v3:
Trim white space at end of line.
v4:
Remove unused local variable.
Cc: Feng Tian <feng.tian@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>
