lookasid.c File Reference

#include "exp.h"

Go to the source code of this file.

Defines
#define	MAXIMUM_SCAN_PERIOD   4
#define	MINIMUM_LOOKASIDE_DEPTH   4
#define	MINIMUM_ALLOCATION_THRESHOLD   25
Functions
LOGICAL	ExpComputeLookasideDepth (IN ULONG Allocates, IN ULONG Misses, IN USHORT MaximumDepth, IN OUT PUSHORT Depth)
PVOID	ExpDummyAllocate (IN POOL_TYPE PoolType, IN SIZE_T NumberOfBytes, IN ULONG Tag)
LOGICAL	ExpScanGeneralLookasideList (IN PLIST_ENTRY ListHead, IN PKSPIN_LOCK SpinLock)
LOGICAL	ExpScanPoolLookasideList (IN PLIST_ENTRY ListHead)
VOID	ExAdjustLookasideDepth (VOID)
VOID	ExInitializeNPagedLookasideList (IN PNPAGED_LOOKASIDE_LIST Lookaside, IN PALLOCATE_FUNCTION Allocate, IN PFREE_FUNCTION Free, IN ULONG Flags, IN SIZE_T Size, IN ULONG Tag, IN USHORT Depth)
VOID	ExDeleteNPagedLookasideList (IN PNPAGED_LOOKASIDE_LIST Lookaside)
VOID	ExInitializePagedLookasideList (IN PPAGED_LOOKASIDE_LIST Lookaside, IN PALLOCATE_FUNCTION Allocate, IN PFREE_FUNCTION Free, IN ULONG Flags, IN SIZE_T Size, IN ULONG Tag, IN USHORT Depth)
VOID	ExDeletePagedLookasideList (IN PPAGED_LOOKASIDE_LIST Lookaside)
PVOID	ExAllocateFromPagedLookasideList (IN PPAGED_LOOKASIDE_LIST Lookaside)
VOID	ExFreeToPagedLookasideList (IN PPAGED_LOOKASIDE_LIST Lookaside, IN PVOID Entry)
Variables
LIST_ENTRY	ExNPagedLookasideListHead
KSPIN_LOCK	ExNPagedLookasideLock
LIST_ENTRY	ExPagedLookasideListHead
KSPIN_LOCK	ExPagedLookasideLock
LIST_ENTRY	ExPoolLookasideListHead
ULONG	ExpAdjustScanPeriod = 1
ULONG	ExpCurrentScanPeriod = 1

---

Define Documentation

#define MAXIMUM_SCAN_PERIOD   4

Definition at line 27 of file ex/lookasid.c. Referenced by ExAdjustLookasideDepth().

#define MINIMUM_ALLOCATION_THRESHOLD   25

Definition at line 39 of file ex/lookasid.c. Referenced by ExpComputeLookasideDepth(), and RtlpAdjustHeapLookasideDepth().

#define MINIMUM_LOOKASIDE_DEPTH   4

Definition at line 33 of file ex/lookasid.c. Referenced by ExInitializeNPagedLookasideList(), ExInitializePagedLookasideList(), ExpComputeLookasideDepth(), RtlpAdjustHeapLookasideDepth(), and RtlpInitializeHeapLookaside().

---

Function Documentation

VOID ExAdjustLookasideDepth (  VOID   )

Definition at line 89 of file ex/lookasid.c. References ExNPagedLookasideListHead, ExNPagedLookasideLock, ExpAdjustScanPeriod, ExPagedLookasideListHead, ExPagedLookasideLock, ExpCurrentScanPeriod, ExPoolLookasideListHead, ExpScanGeneralLookasideList(), ExpScanPoolLookasideList(), FALSE, and MAXIMUM_SCAN_PERIOD. Referenced by KeBalanceSetManager(). 00095 : 00096 00097 This function is called periodically to adjust the maximum depth of 00098 all lookaside lists. 00099 00100 Arguments: 00101 00102 None. 00103 00104 Return Value: 00105 00106 None. 00107 00108 --*/ 00109 00110 { 00111 00112 LOGICAL Changes; 00113 00114 // 00115 // Decrement the scan period and check if it is time to dynamically 00116 // adjust the maximum depth of lookaside lists. 00117 // 00118 00119 ExpCurrentScanPeriod -= 1; 00120 if (ExpCurrentScanPeriod == 0) { 00121 Changes = FALSE; 00122 00123 // 00124 // Scan the general paged and nonpaged lookaside lists. 00125 // 00126 00127 Changes |= ExpScanGeneralLookasideList(&ExNPagedLookasideListHead, 00128 &ExNPagedLookasideLock); 00129 00130 Changes |= ExpScanGeneralLookasideList(&ExPagedLookasideListHead, 00131 &ExPagedLookasideLock); 00132 00133 // 00134 // Scan the pool paged and nonpaged lookaside lists; 00135 // 00136 00137 Changes |= ExpScanPoolLookasideList(&ExPoolLookasideListHead); 00138 00139 // 00140 // If any changes were made to the depth of any lookaside list during 00141 // this scan period, then lower the scan period to the minimum value. 00142 // Otherwise, attempt to raise the scan period. 00143 // 00144 00145 if (Changes != FALSE) { 00146 ExpAdjustScanPeriod = 1; 00147 00148 } else { 00149 if (ExpAdjustScanPeriod != MAXIMUM_SCAN_PERIOD) { 00150 ExpAdjustScanPeriod += 1; 00151 } 00152 } 00153 00154 ExpCurrentScanPeriod = ExpAdjustScanPeriod; 00155 } 00156 00157 return; 00158 }

PVOID ExAllocateFromPagedLookasideList (  IN PPAGED_LOOKASIDE_LIST  Lookaside  )

Definition at line 681 of file ex/lookasid.c. References ExInterlockedPopEntrySList(), Isx86FeaturePresent, KF_CMPXCHG8B, and NULL. 00687 : 00688 00689 This function removes (pops) the first entry from the specified 00690 paged lookaside list. 00691 00692 Arguments: 00693 00694 Lookaside - Supplies a pointer to a paged lookaside list structure. 00695 00696 Return Value: 00697 00698 If an entry is removed from the specified lookaside list, then the 00699 address of the entry is returned as the function value. Otherwise, 00700 NULL is returned. 00701 00702 --*/ 00703 00704 { 00705 00706 PVOID Entry; 00707 00708 Lookaside->L.TotalAllocates += 1; 00709 00710 if (Isx86FeaturePresent(KF_CMPXCHG8B)) { 00711 if ((Entry = ExInterlockedPopEntrySList(&Lookaside->L.ListHead, 00712 NULL)) == NULL) { 00713 00714 Lookaside->L.AllocateMisses += 1; 00715 Entry = (Lookaside->L.Allocate)(Lookaside->L.Type, 00716 Lookaside->L.Size, 00717 Lookaside->L.Tag); 00718 } 00719 00720 return Entry; 00721 } 00722 00723 ExAcquireFastMutex(&Lookaside->Lock); 00724 Entry = PopEntryList(&Lookaside->L.ListHead.Next); 00725 if (Entry == NULL) { 00726 ExReleaseFastMutex(&Lookaside->Lock); 00727 Lookaside->L.AllocateMisses += 1; 00728 Entry = (Lookaside->L.Allocate)(Lookaside->L.Type, 00729 Lookaside->L.Size, 00730 Lookaside->L.Tag); 00731 00732 } else { 00733 Lookaside->L.ListHead.Depth -= 1; 00734 ExReleaseFastMutex(&Lookaside->Lock); 00735 } 00736 00737 return Entry; 00738 }

VOID ExDeleteNPagedLookasideList (  IN PNPAGED_LOOKASIDE_LIST  Lookaside  )

Definition at line 494 of file ex/lookasid.c. References ExAllocateFromNPagedLookasideList(), ExNPagedLookasideLock, ExpDummyAllocate(), and NULL. 00500 : 00501 00502 This function removes a paged lookaside structure from the system paged 00503 lookaside list and frees any entries specified by the lookaside structure. 00504 00505 Arguments: 00506 00507 Lookaside - Supplies a pointer to a nonpaged lookaside list structure. 00508 00509 Return Value: 00510 00511 None. 00512 00513 --*/ 00514 00515 { 00516 00517 PVOID Entry; 00518 KIRQL OldIrql; 00519 00520 // 00521 // Acquire the nonpaged system lookaside list lock and remove the 00522 // specified lookaside list structure from the list. 00523 // 00524 00525 ExAcquireSpinLock(&ExNPagedLookasideLock, &OldIrql); 00526 RemoveEntryList(&Lookaside->L.ListEntry); 00527 ExReleaseSpinLock(&ExNPagedLookasideLock, OldIrql); 00528 00529 // 00530 // Remove all pool entries from the specified lookaside structure 00531 // and free them. 00532 // 00533 00534 Lookaside->L.Allocate = ExpDummyAllocate; 00535 while ((Entry = ExAllocateFromNPagedLookasideList(Lookaside)) != NULL) { 00536 (Lookaside->L.Free)(Entry); 00537 } 00538 00539 return; 00540 }

VOID ExDeletePagedLookasideList (  IN PPAGED_LOOKASIDE_LIST  Lookaside  )

Definition at line 629 of file ex/lookasid.c. References ExAllocateFromPagedLookasideList(), ExPagedLookasideLock, ExpDummyAllocate(), and NULL. Referenced by FreeCachedQueues(), and Win32kNtUserCleanup(). : This function removes a paged lookaside structure from the system paged lookaside list and frees any entries specified by the lookaside structure. Arguments: Lookaside - Supplies a pointer to a paged lookaside list structure. Return Value: None. --*/ { PVOID Entry; KIRQL OldIrql; // // Acquire the paged system lookaside list lock and remove the // specified lookaside list structure from the list. // ExAcquireSpinLock(&ExPagedLookasideLock, &OldIrql); RemoveEntryList(&Lookaside->L.ListEntry); ExReleaseSpinLock(&ExPagedLookasideLock, OldIrql); // // Remove all pool entries from the specified lookaside structure // and free them. // Lookaside->L.Allocate = ExpDummyAllocate; while ((Entry = ExAllocateFromPagedLookasideList(Lookaside)) != NULL) { (Lookaside->L.Free)(Entry); } return; }

VOID ExFreeToPagedLookasideList (  IN PPAGED_LOOKASIDE_LIST  Lookaside, IN PVOID  Entry )

Definition at line 741 of file ex/lookasid.c. References ExInterlockedPushEntrySList(), ExQueryDepthSList, Isx86FeaturePresent, KF_CMPXCHG8B, and NULL. : This function inserts (pushes) the specified entry into the specified paged lookaside list. Arguments: Lookaside - Supplies a pointer to a paged lookaside list structure. Entry - Supples a pointer to the entry that is inserted in the lookaside list. Return Value: None. --*/ { Lookaside->L.TotalFrees += 1; if (Isx86FeaturePresent(KF_CMPXCHG8B)) { if (ExQueryDepthSList(&Lookaside->L.ListHead) >= Lookaside->L.Depth) { Lookaside->L.FreeMisses += 1; (Lookaside->L.Free)(Entry); } else { ExInterlockedPushEntrySList(&Lookaside->L.ListHead, (PSINGLE_LIST_ENTRY)Entry, NULL); } return; } ExAcquireFastMutex(&Lookaside->Lock); if (ExQueryDepthSList(&Lookaside->L.ListHead) >= Lookaside->L.Depth) { ExReleaseFastMutex(&Lookaside->Lock); Lookaside->L.FreeMisses += 1; (Lookaside->L.Free)(Entry); } else { PushEntryList(&Lookaside->L.ListHead.Next, (PSINGLE_LIST_ENTRY)Entry); Lookaside->L.ListHead.Depth += 1; ExReleaseFastMutex(&Lookaside->Lock); } return; }

VOID ExInitializeNPagedLookasideList (  IN PNPAGED_LOOKASIDE_LIST  Lookaside, IN PALLOCATE_FUNCTION  Allocate, IN PFREE_FUNCTION  Free, IN ULONG  Flags, IN SIZE_T  Size, IN ULONG  Tag, IN USHORT  Depth )

Definition at line 408 of file ex/lookasid.c. References ExAllocatePoolWithTag, ExFreePool(), ExInitializeSListHead, ExInterlockedInsertTailList(), ExNPagedLookasideListHead, ExNPagedLookasideLock, KeInitializeSpinLock(), MINIMUM_LOOKASIDE_DEPTH, NonPagedPool, NULL, and Size. Referenced by CcInitializeCacheManager(), FsRtlInitializeFileLocks(), FsRtlInitializeLargeMcbs(), IoInitSystem(), and ObInitSystem(). 00420 : 00421 00422 This function initializes a nonpaged lookaside list structure and inserts 00423 the structure in the system nonpaged lookaside list. 00424 00425 Arguments: 00426 00427 Lookaside - Supplies a pointer to a nonpaged lookaside list structure. 00428 00429 Allocate - Supplies an optional pointer to an allocate function. 00430 00431 Free - Supplies an optional pointer to a free function. 00432 00433 Flags - Supplies the pool allocation flags which are merged with the 00434 pool allocation type (NonPagedPool) to control pool allocation. 00435 00436 Size - Supplies the size for the lookaside list entries. 00437 00438 Tag - Supplies the pool tag for the lookaside list entries. 00439 00440 Depth - Supplies the maximum depth of the lookaside list. 00441 00442 Return Value: 00443 00444 None. 00445 00446 --*/ 00447 00448 { 00449 00450 // 00451 // Initialize the lookaside list structure. 00452 // 00453 00454 ExInitializeSListHead(&Lookaside->L.ListHead); 00455 Lookaside->L.Depth = MINIMUM_LOOKASIDE_DEPTH; 00456 Lookaside->L.MaximumDepth = 256; //Depth; 00457 Lookaside->L.TotalAllocates = 0; 00458 Lookaside->L.AllocateMisses = 0; 00459 Lookaside->L.TotalFrees = 0; 00460 Lookaside->L.FreeMisses = 0; 00461 Lookaside->L.Type = NonPagedPool | Flags; 00462 Lookaside->L.Tag = Tag; 00463 Lookaside->L.Size = (ULONG)Size; 00464 if (Allocate == NULL) { 00465 Lookaside->L.Allocate = ExAllocatePoolWithTag; 00466 00467 } else { 00468 Lookaside->L.Allocate = Allocate; 00469 } 00470 00471 if (Free == NULL) { 00472 Lookaside->L.Free = ExFreePool; 00473 00474 } else { 00475 Lookaside->L.Free = Free; 00476 } 00477 00478 Lookaside->L.LastTotalAllocates = 0; 00479 Lookaside->L.LastAllocateMisses = 0; 00480 KeInitializeSpinLock(&Lookaside->Lock); 00481 00482 // 00483 // Insert the lookaside list structure is the system nonpaged lookaside 00484 // list. 00485 // 00486 00487 ExInterlockedInsertTailList(&ExNPagedLookasideListHead, 00488 &Lookaside->L.ListEntry, 00489 &ExNPagedLookasideLock); 00490 return; 00491 }

VOID ExInitializePagedLookasideList (  IN PPAGED_LOOKASIDE_LIST  Lookaside, IN PALLOCATE_FUNCTION  Allocate, IN PFREE_FUNCTION  Free, IN ULONG  Flags, IN SIZE_T  Size, IN ULONG  Tag, IN USHORT  Depth )

Definition at line 543 of file ex/lookasid.c. References ExAllocatePoolWithTag, ExFreePool(), ExInitializeFastMutex, ExInitializeSListHead, ExInterlockedInsertTailList(), ExPagedLookasideListHead, ExPagedLookasideLock, MINIMUM_LOOKASIDE_DEPTH, NULL, PagedPool, and Size. Referenced by FsRtlInitializeFileLocks(), FsRtlInitializeLargeMcbs(), FsRtlInitializeTunnels(), InitQEntryLookaside(), and InitSMSLookaside(). 00555 : 00556 00557 This function initializes a paged lookaside list structure and inserts 00558 the structure in the system paged lookaside list. 00559 00560 Arguments: 00561 00562 Lookaside - Supplies a pointer to a paged lookaside list structure. 00563 00564 Allocate - Supplies an optional pointer to an allocate function. 00565 00566 Free - Supplies an optional pointer to a free function. 00567 00568 Flags - Supplies the pool allocation flags which are merged with the 00569 pool allocation type (NonPagedPool) to control pool allocation. 00570 00571 Size - Supplies the size for the lookaside list entries. 00572 00573 Tag - Supplies the pool tag for the lookaside list entries. 00574 00575 Depth - Supplies the maximum depth of the lookaside list. 00576 00577 Return Value: 00578 00579 None. 00580 00581 --*/ 00582 00583 { 00584 00585 // 00586 // Initialize the lookaside list structure. 00587 // 00588 00589 ExInitializeSListHead(&Lookaside->L.ListHead); 00590 Lookaside->L.Depth = MINIMUM_LOOKASIDE_DEPTH; 00591 Lookaside->L.MaximumDepth = 256; //Depth; 00592 Lookaside->L.TotalAllocates = 0; 00593 Lookaside->L.AllocateMisses = 0; 00594 Lookaside->L.TotalFrees = 0; 00595 Lookaside->L.FreeMisses = 0; 00596 Lookaside->L.Type = PagedPool | Flags; 00597 Lookaside->L.Tag = Tag; 00598 Lookaside->L.Size = (ULONG)Size; 00599 if (Allocate == NULL) { 00600 Lookaside->L.Allocate = ExAllocatePoolWithTag; 00601 00602 } else { 00603 Lookaside->L.Allocate = Allocate; 00604 } 00605 00606 if (Free == NULL) { 00607 Lookaside->L.Free = ExFreePool; 00608 00609 } else { 00610 Lookaside->L.Free = Free; 00611 } 00612 00613 Lookaside->L.LastTotalAllocates = 0; 00614 Lookaside->L.LastAllocateMisses = 0; 00615 ExInitializeFastMutex(&Lookaside->Lock); 00616 00617 // 00618 // Insert the lookaside list structure in the system paged lookaside 00619 // list. 00620 // 00621 00622 ExInterlockedInsertTailList(&ExPagedLookasideListHead, 00623 &Lookaside->L.ListEntry, 00624 &ExPagedLookasideLock); 00625 return; 00626 }

LOGICAL ExpComputeLookasideDepth (  IN ULONG  Allocates, IN ULONG  Misses, IN USHORT  MaximumDepth, IN OUT PUSHORT  Depth )

Definition at line 161 of file ex/lookasid.c. References ExpAdjustScanPeriod, FALSE, MINIMUM_ALLOCATION_THRESHOLD, MINIMUM_LOOKASIDE_DEPTH, TRUE, and USHORT. Referenced by ExpScanGeneralLookasideList(), and ExpScanPoolLookasideList(). 00170 : 00171 00172 This function computes the target depth of a lookaside list given the 00173 total allocations and misses during the last scan period and the current 00174 depth. 00175 00176 Arguments: 00177 00178 Allocates - Supplies the total number of allocations during the last 00179 scan period. 00180 00181 Misses - Supplies the total number of allocate misses during the last 00182 scan period. 00183 00184 MaximumDepth - Supplies the maximum depth the lookaside list is allowed 00185 to reach. 00186 00187 Depth - Supplies a pointer to the current lookaside list depth which 00188 receives the target depth. 00189 00190 Return Value: 00191 00192 If the target depth is greater than the current depth, then a value of 00193 TRUE is returned as the function value. Otherwise, a value of FALSE is 00194 returned. 00195 00196 --*/ 00197 00198 { 00199 00200 LOGICAL Changes; 00201 ULONG Ratio; 00202 ULONG Target; 00203 00204 // 00205 // If the allocate rate is less than the mimimum threshold, then lower 00206 // the maximum depth of the lookaside list. Otherwise, if the miss rate 00207 // is less than .5%, then lower the maximum depth. Otherwise, raise the 00208 // maximum depth based on the miss rate. 00209 // 00210 00211 Changes = FALSE; 00212 if (Misses >= Allocates) { 00213 Misses = Allocates; 00214 } 00215 00216 if (Allocates == 0) { 00217 Allocates = 1; 00218 } 00219 00220 Ratio = (Misses * 1000) / Allocates; 00221 Target = *Depth; 00222 if ((Allocates / ExpAdjustScanPeriod) < MINIMUM_ALLOCATION_THRESHOLD) { 00223 if (Target > (MINIMUM_LOOKASIDE_DEPTH + 10)) { 00224 Target -= 10; 00225 00226 } else { 00227 Target = MINIMUM_LOOKASIDE_DEPTH; 00228 } 00229 00230 } else if (Ratio < 5) { 00231 if (Target > (MINIMUM_LOOKASIDE_DEPTH + 1)) { 00232 Target -= 1; 00233 00234 } else { 00235 Target = MINIMUM_LOOKASIDE_DEPTH; 00236 } 00237 00238 } else { 00239 Changes = TRUE; 00240 Target += ((Ratio * MaximumDepth) / (1000 * 2)) + 5; 00241 if (Target > MaximumDepth) { 00242 Target = MaximumDepth; 00243 } 00244 } 00245 00246 *Depth = (USHORT)Target; 00247 return Changes; 00248 }

PVOID ExpDummyAllocate (  IN POOL_TYPE  PoolType, IN SIZE_T  NumberOfBytes, IN ULONG  Tag )

Definition at line 802 of file ex/lookasid.c. References NULL. Referenced by ExDeleteNPagedLookasideList(), and ExDeletePagedLookasideList(). 00810 : 00811 00812 This function is a dummy allocation routine which is used to empty 00813 a lookaside list. 00814 00815 Arguments: 00816 00817 PoolType - Supplies the type of pool to allocate. 00818 00819 NumberOfBytes - supplies the number of bytes to allocate. 00820 00821 Tag - supplies the pool tag. 00822 00823 Return Value: 00824 00825 NULL is returned as the function value. 00826 00827 --*/ 00828 00829 { 00830 00831 return NULL; 00832 } }

LOGICAL ExpScanGeneralLookasideList (  IN PLIST_ENTRY  ListHead, IN PKSPIN_LOCK  SpinLock )

Definition at line 251 of file ex/lookasid.c. References _GENERAL_LOOKASIDE::AllocateMisses, _GENERAL_LOOKASIDE::Depth, ExpComputeLookasideDepth(), FALSE, _PAGED_LOOKASIDE_LIST::L, L, _GENERAL_LOOKASIDE::LastAllocateMisses, _GENERAL_LOOKASIDE::LastTotalAllocates, _GENERAL_LOOKASIDE::MaximumDepth, and _GENERAL_LOOKASIDE::TotalAllocates. Referenced by ExAdjustLookasideDepth(). 00258 : 00259 00260 This function scans the specified list of general lookaside descriptors 00261 and adjusts the maximum depth as necessary. 00262 00263 Arguments: 00264 00265 ListHead - Supplies the address of the listhead for a list of lookaside 00266 descriptors. 00267 00268 SpinLock - Supplies the address of the spinlock to be used to synchronize 00269 access to the list of lookaside descriptors. 00270 00271 Return Value: 00272 00273 A value of TRUE is returned if the maximum depth of any lookaside list 00274 is changed. Otherwise, a value of FALSE is returned. 00275 00276 --*/ 00277 00278 { 00279 00280 ULONG Allocates; 00281 LOGICAL Changes; 00282 PLIST_ENTRY Entry; 00283 PPAGED_LOOKASIDE_LIST Lookaside; 00284 ULONG Misses; 00285 KIRQL OldIrql; 00286 00287 // 00288 // Raise IRQL and acquire the specified spinlock. 00289 // 00290 00291 Changes = FALSE; 00292 ExAcquireSpinLock(SpinLock, &OldIrql); 00293 00294 // 00295 // Scan the specified list of lookaside descriptors and adjust the 00296 // maximum depth as necessary. 00297 // 00298 // N.B. All lookaside list descriptor are treated as if they were 00299 // paged descriptor even though they may be nonpaged descriptors. 00300 // This is possible since both structures are identical except 00301 // for the locking fields which are the last structure fields. 00302 00303 Entry = ListHead->Flink; 00304 while (Entry != ListHead) { 00305 Lookaside = CONTAINING_RECORD(Entry, 00306 PAGED_LOOKASIDE_LIST, 00307 L.ListEntry); 00308 00309 // 00310 // Compute the total number of allocations and misses per second for 00311 // this scan period. 00312 // 00313 00314 Allocates = Lookaside->L.TotalAllocates - Lookaside->L.LastTotalAllocates; 00315 Lookaside->L.LastTotalAllocates = Lookaside->L.TotalAllocates; 00316 Misses = Lookaside->L.AllocateMisses - Lookaside->L.LastAllocateMisses; 00317 Lookaside->L.LastAllocateMisses = Lookaside->L.AllocateMisses; 00318 00319 // 00320 // Compute target depth of lookaside list. 00321 // 00322 00323 Changes |= ExpComputeLookasideDepth(Allocates, 00324 Misses, 00325 Lookaside->L.MaximumDepth, 00326 &Lookaside->L.Depth); 00327 00328 Entry = Entry->Flink; 00329 } 00330 00331 // 00332 // Release spinlock, lower IRQL, and return function value. 00333 // 00334 00335 ExReleaseSpinLock(SpinLock, OldIrql); 00336 return Changes; 00337 }

LOGICAL ExpScanPoolLookasideList (  IN PLIST_ENTRY  ListHead  )

Definition at line 340 of file ex/lookasid.c. References _GENERAL_LOOKASIDE::AllocateHits, _GENERAL_LOOKASIDE::Depth, ExpComputeLookasideDepth(), FALSE, _NPAGED_LOOKASIDE_LIST::L, L, _GENERAL_LOOKASIDE::LastAllocateHits, _GENERAL_LOOKASIDE::LastTotalAllocates, _GENERAL_LOOKASIDE::MaximumDepth, and _GENERAL_LOOKASIDE::TotalAllocates. Referenced by ExAdjustLookasideDepth(). 00346 : 00347 00348 This function scans the specified pool lookaside descriptors and adjusts 00349 the maximum depth as necessary. 00350 00351 Arguments: 00352 00353 ListHead - Supplies a pointer to the list of pool lookaside structures. 00354 00355 Return Value: 00356 00357 A value of TRUE is returned if the maximum depth of any lookaside list 00358 is changed. Otherwise, a value of FALSE is returned. 00359 00360 --*/ 00361 00362 { 00363 00364 ULONG Allocates; 00365 LOGICAL Changes; 00366 PNPAGED_LOOKASIDE_LIST Lookaside; 00367 PLIST_ENTRY NextEntry; 00368 ULONG Misses; 00369 00370 // 00371 // Scan the specified list of lookaside descriptors and adjust the 00372 // maximum depth as necessary. 00373 // 00374 00375 Changes = FALSE; 00376 NextEntry = ListHead->Flink; 00377 while (NextEntry != ListHead) { 00378 Lookaside = CONTAINING_RECORD(NextEntry, 00379 NPAGED_LOOKASIDE_LIST, 00380 L.ListEntry); 00381 00382 // 00383 // Compute the total number of allocations and misses per second for 00384 // this scan period. 00385 // 00386 00387 Allocates = Lookaside->L.TotalAllocates - Lookaside->L.LastTotalAllocates; 00388 Lookaside->L.LastTotalAllocates = Lookaside->L.TotalAllocates; 00389 Misses = Allocates - (Lookaside->L.AllocateHits - Lookaside->L.LastAllocateHits); 00390 Lookaside->L.LastAllocateHits = Lookaside->L.AllocateHits; 00391 00392 // 00393 // Compute target depth of lookaside list. 00394 // 00395 00396 Changes |= ExpComputeLookasideDepth(Allocates, 00397 Misses, 00398 Lookaside->L.MaximumDepth, 00399 &Lookaside->L.Depth); 00400 00401 NextEntry = NextEntry->Flink; 00402 } 00403 00404 return Changes; 00405 }

---

Variable Documentation

LIST_ENTRY ExNPagedLookasideListHead

Definition at line 75 of file ex/lookasid.c. Referenced by ExAdjustLookasideDepth(), ExInitializeNPagedLookasideList(), and ExpGetLookasideInformation().

KSPIN_LOCK ExNPagedLookasideLock

Definition at line 76 of file ex/lookasid.c. Referenced by ExAdjustLookasideDepth(), ExDeleteNPagedLookasideList(), ExInitializeNPagedLookasideList(), and ExpGetLookasideInformation().

ULONG ExpAdjustScanPeriod = 1

Definition at line 85 of file ex/lookasid.c. Referenced by ExAdjustLookasideDepth(), and ExpComputeLookasideDepth().

LIST_ENTRY ExPagedLookasideListHead

Definition at line 77 of file ex/lookasid.c. Referenced by ExAdjustLookasideDepth(), ExInitializePagedLookasideList(), and ExpGetLookasideInformation().

KSPIN_LOCK ExPagedLookasideLock

Definition at line 78 of file ex/lookasid.c. Referenced by ExAdjustLookasideDepth(), ExDeletePagedLookasideList(), ExInitializePagedLookasideList(), and ExpGetLookasideInformation().

ULONG ExpCurrentScanPeriod = 1

Definition at line 86 of file ex/lookasid.c. Referenced by ExAdjustLookasideDepth().

LIST_ENTRY ExPoolLookasideListHead

Definition at line 79 of file ex/lookasid.c. Referenced by ExAdjustLookasideDepth(), ExpGetLookasideInformation(), and ExQueryPoolUsage().

---