ntnap.c File Reference

#include <nt.h>
#include <ntrtl.h>
#include <nturtl.h>
#include <string.h>
#include "ntnapdef.h"
#include "ntnap.h"

Go to the source code of this file.

Functions
VOID	NapDllInit (VOID)
NTSTATUS	NapCreateDataSection (PNAPCONTROL *NapSectionPointer)
VOID	NapRecordInfo (IN ULONG ServiceNumber, IN LARGE_INTEGER Counters[])
NTSTATUS	NapClearData (VOID)
NTSTATUS	NapRetrieveData (OUT NAPDATA *NapApiData, OUT PCHAR **NapApiNames, OUT PLARGE_INTEGER *NapCounterFrequency)
NTSTATUS	NapGetApiCount (OUT PULONG NapApiCount)
NTSTATUS	NapPause (VOID)
NTSTATUS	NapResume (VOID)
Variables
BOOLEAN	NapInitialized = FALSE
LARGE_INTEGER	NapFrequency
PNAPCONTROL	NapControl = NULL
PNAPDATA	NapProfilingData = NULL

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Function Documentation

NTSTATUS NapClearData (  VOID   )

Definition at line 378 of file ntnap.c. References L, MAX_LONG, MAX_ULONG, NapProfilingData, and NapReleaseSpinLock(). Referenced by NapDllInit(). : NapClearData() is called to clear all the counters and timers. The calibration counters are not cleared. For the rest, if not previously collected, the data will be lost. Arguments: None Return Value: Status --*/ { ULONG ServiceNumber; // // Initialize the first one after the calibration data // NapAcquireSpinLock(&(NapProfilingData[1].NapLock)); NapProfilingData[1].Calls = 0L; NapProfilingData[1].TimingErrors = 0L; NapProfilingData[1].TotalTime.HighPart = 0L; NapProfilingData[1].TotalTime.LowPart = 0L; NapProfilingData[1].FirstTime.HighPart = 0L; NapProfilingData[1].FirstTime.LowPart = 0L; NapProfilingData[1].MaxTime.HighPart = 0L; NapProfilingData[1].MaxTime.LowPart = 0L; NapProfilingData[1].MinTime.HighPart = MAX_LONG; NapProfilingData[1].MinTime.LowPart = MAX_ULONG; // // Now use the initialized first one to initialize the rest // for (ServiceNumber = 2; ServiceNumber <= NAP_API_COUNT; ServiceNumber++) { NapAcquireSpinLock(&(NapProfilingData[ServiceNumber].NapLock)); NapProfilingData[ServiceNumber] = NapProfilingData[1]; NapReleaseSpinLock(&(NapProfilingData[ServiceNumber].NapLock)); } NapReleaseSpinLock(&(NapProfilingData[1].NapLock)); return(STATUS_SUCCESS); }

NTSTATUS NapCreateDataSection (  PNAPCONTROL *  NapSectionPointer  )

Definition at line 164 of file ntnap.c. References NT_SUCCESS, NtCreateSection(), NtMapViewOfSection(), NTSTATUS(), NULL, ObjectAttributes, and Status. Referenced by NapDllInit(). : NapCreateData() is called to create the profiling data section. One section, named "\NapDataSection", is used for the whole system. It is accessible by anyone, so don't mess it up. Arguments: NapSectionPointer - a pointer to a pointer which will be set to to point to the beginning of the section. Return Value: Status --*/ { NTSTATUS Status; HANDLE NapSectionHandle; HANDLE MyProcess; STRING NapSectionName; OBJECT_ATTRIBUTES ObjectAttributes; LARGE_INTEGER AllocationSize; ULONG ViewSize; PNAPCONTROL SectionPointer; // // Initialize object attributes for the dump file // NapSectionName.Length = 15; NapSectionName.MaximumLength = 15; NapSectionName.Buffer = "\\NapDataSection"; ObjectAttributes.Length = sizeof(OBJECT_ATTRIBUTES); ObjectAttributes.ObjectName = &NapSectionName; ObjectAttributes.RootDirectory = NULL; ObjectAttributes.SecurityDescriptor = NULL; ObjectAttributes.SecurityQualityOfService = NULL; ObjectAttributes.Attributes = OBJ_OPENIF | OBJ_CASE_INSENSITIVE; AllocationSize.HighPart = 0; AllocationSize.LowPart = (NAP_API_COUNT + 1) * sizeof(NAPDATA); Status = NtCreateSection(&NapSectionHandle, SECTION_MAP_READ | SECTION_MAP_WRITE, &ObjectAttributes, &AllocationSize, PAGE_READWRITE, SEC_COMMIT, NULL); if (NT_SUCCESS(Status)) { MyProcess = NtCurrentProcess(); ViewSize = AllocationSize.LowPart; SectionPointer = NULL; Status = NtMapViewOfSection(NapSectionHandle, MyProcess, (PVOID *)&SectionPointer, 0, AllocationSize.LowPart, NULL, &ViewSize, ViewUnmap, MEM_TOP_DOWN, PAGE_READWRITE); *NapSectionPointer = SectionPointer; } return(Status); }

VOID NapDllInit (  VOID   )

Definition at line 61 of file ntnap.c. References _NAPCONTROL::Initialized, L, MAX_LONG, MAX_ULONG, NapCalibrate(), NapClearData(), NapControl, NapCreateDataSection(), NapFrequency, NapInitialized, NapProfilingData, NT_SUCCESS, NtQueryPerformanceCounter(), NUM_ITERATIONS, _NAPCONTROL::Paused, and TRUE. : NapDllInit() is called before calling any profiling api. It initializes profiling for the NT native API's. NOTE: Initialization occurs only once and is controlled by the NapInitDone global flag. Arguments: None Return Value: None --*/ { ULONG i; LARGE_INTEGER CurrentCounter; if (!NapInitialized) { // // Instance data for this process's ntdll.dll not yet initialized. // NapInitialized = TRUE; // // Get Counter frequency (current counter value is thrown away) // This call is not profiled because NapControl == NULL here. // NtQueryPerformanceCounter(&CurrentCounter, &NapFrequency); // // Allocate or open data section for api profiling data. // if (NT_SUCCESS(NapCreateDataSection(&NapControl))) { NapProfilingData = (PNAPDATA)(NapControl + 1); if (!NapControl->Initialized) { // // We are the first process to get here: we jsut // allocated the section, so must initialize it. // NapControl->Initialized = TRUE; NapControl->Paused = 0; // // Clear the data area used for calibration data. // NapProfilingData[0].NapLock = 0L; NapProfilingData[0].Calls = 0L; NapProfilingData[0].TimingErrors = 0L; NapProfilingData[0].TotalTime.HighPart = 0L; NapProfilingData[0].TotalTime.LowPart = 0L; NapProfilingData[0].FirstTime.HighPart = 0L; NapProfilingData[0].FirstTime.LowPart = 0L; NapProfilingData[0].MaxTime.HighPart = 0L; NapProfilingData[0].MaxTime.LowPart = 0L; NapProfilingData[0].MinTime.HighPart = MAX_LONG; NapProfilingData[0].MinTime.LowPart = MAX_ULONG; // // Clear the rest of the data collection area // NapClearData(); // // Calibrate time overhead from profiling. We care mostly // about the minimum time here, to avoid extra time from // interrupts etc. // for (i=0; i<NUM_ITERATIONS; i++) { NapCalibrate(); } } } } }

NTSTATUS NapGetApiCount (  OUT PULONG  NapApiCount  )

Definition at line 500 of file ntnap.c. : NapGetApiCount() is called to get the number of API's which are being profiled. This can then be used to allocate an array for receiving the data from NapReturnData. Arguments: NapApiCount - A pointer throug which the count is returned. Return Value: Status --*/ { *NapApiCount = NAP_API_COUNT; return(STATUS_SUCCESS); }

NTSTATUS NapPause (  VOID   )

Definition at line 535 of file ntnap.c. References NapControl, and _NAPCONTROL::Paused. : NapPause() is called to temporarily cease data collection. Data collection is resumed by a companion call to NapResume. Arguments: None Return Value: Status --*/ { NapControl->Paused++; return(STATUS_SUCCESS); }

VOID NapRecordInfo (  IN ULONG  ServiceNumber, IN LARGE_INTEGER  Counters[] )

Definition at line 255 of file ntnap.c. References NapControl, NapProfilingData, NapReleaseSpinLock(), NULL, and _NAPCONTROL::Paused. : NapRecordInfo() is called after the API being measured has returned, and the value of the performance counter has been obtained. NOTE: Initialization occurs only once and is controlled by the NapInitDone global flag. Arguments: ServiceNumber - the number of the service being measured. -1 is reserved for calibration. Counters - a pointer to the value of the counter after the call to the measured routine. Followed immediately in memory by the value of the counter before the call to the measured routine. Return Value: None --*/ { LARGE_INTEGER ElapsedTime; LARGE_INTEGER Difference; // // First make sure we have been initialized // if (NapControl != NULL) { // // Check to be sure profiling is not paused if (NapControl->Paused == 0) { // // Since ServiceNumber -1 is used for calibration, bump same // so indexes start at 0. // ServiceNumber++; // // Prevent others from changing data at the same time // we are. // NapAcquireSpinLock(&(NapProfilingData[ServiceNumber].NapLock)); // // Record API info // NapProfilingData[ServiceNumber].Calls++; // // Elapsed time is end time minus start time // ElapsedTime = RtlLargeIntegerSubtract(Counters[0],Counters[1]); // // Now add elapsed time to total time // NapProfilingData[ServiceNumber].TotalTime = RtlLargeIntegerAdd(NapProfilingData[ServiceNumber].TotalTime, ElapsedTime); if (NapProfilingData[ServiceNumber].Calls == 1) { NapProfilingData[ServiceNumber].FirstTime = ElapsedTime; } else { Difference = RtlLargeIntegerSubtract( NapProfilingData[ServiceNumber].MaxTime, ElapsedTime); if (Difference.HighPart < 0) { // // A new maximum was attained // NapProfilingData[ServiceNumber].MaxTime = ElapsedTime; } Difference = RtlLargeIntegerSubtract( ElapsedTime, NapProfilingData[ServiceNumber].MinTime); if (Difference.HighPart < 0) { // // A new minimum was attained // NapProfilingData[ServiceNumber].MinTime = ElapsedTime; } } NapReleaseSpinLock(&(NapProfilingData[ServiceNumber].NapLock)); } } }

NTSTATUS NapResume (  VOID   )

Definition at line 565 of file ntnap.c. References NapControl, and _NAPCONTROL::Paused. 00571 : 00572 00573 NapResume() is called to resume data collection after a companion 00574 call to NapPause. 00575 00576 Arguments: 00577 00578 None 00579 00580 Return Value: 00581 00582 Status 00583 00584 --*/ 00585 00586 00587 { 00588 NapControl->Paused--; 00589 00590 return(STATUS_SUCCESS); 00591 } }

NTSTATUS NapRetrieveData (  OUT NAPDATA *  NapApiData, OUT PCHAR **  NapApiNames, OUT PLARGE_INTEGER *  NapCounterFrequency )

Definition at line 442 of file ntnap.c. References NapFrequency, NapNames, NapProfilingData, and NapReleaseSpinLock(). : NapRetrieveData() is called to get all the relevant data about API's that have been profiled. It is wise to call NapPause() before calling this, and NapResume() afterwards. Can't just do these in here, 'cause you may be doing stuff outside of this call you don't want profiled. Arguments: NapApiData - a pointer to a buffer to which is copied the array of counters; must be large enough for NAP_API_COUNT+1; call NapGetApiCount to obtain needed size. NapApiNames - a pointer to which is copied a pointer to an array of pointers to API names NapCounterFrequency - a buffer to which is copied the frequency of the performance counter Return Value: Status --*/ { ULONG ServiceNumber; *NapApiNames = NapNames; *NapCounterFrequency = &NapFrequency; for (ServiceNumber = 0; ServiceNumber <= NAP_API_COUNT; ServiceNumber++) { NapAcquireSpinLock(&(NapProfilingData[ServiceNumber].NapLock)); NapApiData[ServiceNumber] = NapProfilingData[ServiceNumber]; NapReleaseSpinLock(&(NapProfilingData[ServiceNumber].NapLock)); NapReleaseSpinLock(&(NapApiData[ServiceNumber].NapLock)); } return(STATUS_SUCCESS); }

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Variable Documentation

PNAPCONTROL NapControl = NULL

Definition at line 48 of file ntnap.c. Referenced by NapDllInit(), NapPause(), NapRecordInfo(), and NapResume().

LARGE_INTEGER NapFrequency

Definition at line 42 of file ntnap.c. Referenced by NapDllInit(), and NapRetrieveData().

BOOLEAN NapInitialized = FALSE

Definition at line 36 of file ntnap.c. Referenced by NapDllInit().

PNAPDATA NapProfilingData = NULL

Definition at line 57 of file ntnap.c. Referenced by NapClearData(), NapDllInit(), NapRecordInfo(), and NapRetrieveData().

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