ArmPkg Profiling

We will take the ARM Versatile Express TC2 (big.LITTLE test chip) as an example in this page.

1. Build UEFI in Release build & Copy the binary to the board. See the instructions in this wiki page

2. Identify the start and end point of your trace. Example on TC2, we want to measure from the start of UEFI at 0xB0000000 - defined into ArmVExpress-CTA15-A7.fdf

[FD.ARM_VEXPRESS_CTA15A7_EFI]
BaseAddress   = 0xB0000000|gArmTokenSpaceGuid.PcdFdBaseAddress  # The base address of the Firmware in remapped DRAM.
Size          = 0x000B0000|gArmTokenSpaceGuid.PcdFdSize         # The size in bytes of the FLASH Device

... until the start of Linux.
To identfy where we will start Linux we need to load the symbol of the BDS.
So start UEFI a first time on the target up to the Boot menu.

Load all the symbols with DS-5 (symbols for Pre-EFI and UEFI phases):

source "/home/olivier/tianocore/ArmPlatformPkg/Scripts/Ds5/cmd_load_symbols.py" -f (0xB0000000,0x000B0000) -m (0x80000000,0x40000000) -v -a

Save the output into a file and replace the entry line to make DS-5 command line. Example:

From:

Add symbols of /home/olivier/tianocore/Build/ArmVExpress-CTA15-A7/RELEASE_GCC48/ARM/ArmPlatformPkg/PrePi/PeiMPCore/DEBUG/ArmPlatformPrePiMPCore.dll at 0xb0000180
Add symbols of /home/olivier/tianocore/Build/ArmVExpress-CTA15-A7/RELEASE_GCC48/ARM/MdeModulePkg/Core/Dxe/DxeMain/DEBUG/DxeCore.dll at 0xbfd62240
Add symbols of /home/olivier/tianocore/Build/ArmVExpress-CTA15-A7/RELEASE_GCC48/ARM/ArmPkg/Drivers/CpuDxe/CpuDxe/DEBUG/ArmCpuDxe.dll at 0xbfd14240
(...)

To:

add-symbol-file /home/olivier/tianocore/Build/ArmVExpress-CTA15-A7/RELEASE_GCC48/ARM/ArmPlatformPkg/PrePi/PeiMPCore/DEBUG/ArmPlatformPrePiMPCore.dll 0xb0000180
add-symbol-file /home/olivier/tianocore/Build/ArmVExpress-CTA15-A7/RELEASE_GCC48/ARM/MdeModulePkg/Core/Dxe/DxeMain/DEBUG/DxeCore.dll 0xbfd62240
add-symbol-file /home/olivier/tianocore/Build/ArmVExpress-CTA15-A7/RELEASE_GCC48/ARM/ArmPkg/Drivers/CpuDxe/CpuDxe/DEBUG/ArmCpuDxe.dll 0xbfd14240
(...)

Save the file into symbols.ds

Go to the assembly view of 'StartLinux'. Find where we start Linux and set a hardware breakpoint at this location. Image:uefi-profile1.png

Set a hardware breakpoint at the start of UEFI:

hbreak -p *S:0xB0000000

4. After disconnecting the debugger, restart the ARM Versatile Express.

5. Setting up DS-5 for DSTREAM trace with UEFI
This tutorial assumes you have already set up DS-5 for hardware debugging UEFI. If you haven't, help can be found here.

Ensure that your DSTREAM's debug probe is connected via a Mictor-38 to the target's trace port. This is in addition to the JTAG connection.

6. Open the Debug Configurations menu and from there open the DTSL Options window: Image:uefi-profile2.png In the Trace Capture tab, select "DSTREAM 4GB Trace Buffer". The other settings are optional. Image:uefi-profile3.png

In the Core Trace tab, select "Enable core trace", "Enable core trace", for each core you want to trace, and optionally "Cycle accurate trace". Image:uefi-profile4.png

On TC2, you should now be in the ARM Boot Monitor Menu.
Image:uefi-profile5.png

7. Connect the debugger.

8. Enable your two hardware breakpoints (the start and stop of your trace).

9. Load all the symbols (ie: 'source symbols.ds'). Symbols must be loaded before starting the acquisition.

10. Resume the execution. Start UEFI by typing:

flash run uefi

Program execution should stop at address 0xB0000000.

11. Clear the trace and resume the execution.

UEFI will now boot. As soon as you enter into the Boot Menu press the boot entry (another alternative would be to automatically start Linux by setting PcdTimeout... to 0). Program execution should stop again when reaching the breakpoint you added in stop address. Image:uefi-profile6.png

Results

After some post-processing here are the list of the 20 functions that consume the more cycles on the UEFI Firmware of the ARM Versatile Express TC2.

Module Name / Function Name	Cycle	Percentage	Count
ArmPlatformPrePiMPCore.dll/LzmaDec_DecodeReal	1538397019	33%	9
ArmCpuDxe.dll/ArmCleanInvalidateDataCacheEntryBySetWay	1210112914	26%	18487296
ArmPlatformBds.dll/InternalMemCopyMem	557552792	12%	99
DxeCore.dll/InternalMemCopyMem	372182434	8%	26152
ArmPlatformPrePiMPCore.dll/InternalMemCopyMem	158259634	3%	65
ArmCpuDxe.dll/ArmV7AllDataCachesOperation	156004379	3%	18489420
VariableRuntimeDxe.dll/__aeabi_uread4	67701311	1%	68442
SerialDxe.dll/MmioRead32	49657481	1%	167543
DxeCore.dll/InternalMemCompareMem	48489155	1%	70456
HdLcdGraphicsDxe.dll/MmioRead32	28337835	0%	95824
DxeCore.dll/FwVolBlockReadBlock	27751950	0%	45740
HiiDatabase.dll/InternalMemCopyMem	21179285	0%	8105
ArmVeNorFlashDxe.dll/InternalMemCopyMem	14168462	0%	281
DxeCore.dll/FvCheck	12961574	0%	23193
DxeCore.dll/ReadUnaligned16	12397148	0%	27832
ArmCpuDxe.dll/UpdatePageEntries	11785691	0%	20544
DxeCore.dll/ProduceFVBProtocolOnBuffer	11522208	0%	14
HiiDatabase.dll/__aeabi_memcpy	9341275	0%	20710
DxeCore.dll/CoreSetInterruptState	8332436	0%	32373
ArmPlatformPrePiMPCore.dll/MmioRead32	8261530	0%	27246

Function Name	Cycle	Percentage	COunt
LzmaDec_DecodeReal	1538397019	33%	9
ArmCleanInvalidateDataCacheEntryBySetWay	1215995571	26%	18504704
InternalMemCopyMem	1133754058	24%	36242
ArmV7AllDataCachesOperation	160028408	3%	18515535
MmioRead32	86717719	1%	292770
__aeabi_uread4	67707303	1%	68453
InternalMemCompareMem	52567407	1%	76317
FwVolBlockReadBlock	27751950	0%	45740
ReadUnaligned16	13271790	0%	29780
FvCheck	12961574	0%	23193
UpdatePageEntries	11785691	0%	20544
ProduceFVBProtocolOnBuffer	11522208	0%	14
__aeabi_memcpy	9399629	0%	20814
CoreSetInterruptState	8332436	0%	32373
VariableWriteServiceInitialize	7058548	0%	64019
CompareGuid	6685126	0%	141296
IsErasedFlashBuffer	6550933	0%	1
InternalMemSetMem32	6450910	0%	1800
CoreRestoreTpl	6072718	0%	15192
NarrowGlyphToBlt	5892173	0%	20809

This is based on SVN rev15539 (2014-05-19).