1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
|
AfdSpinLock Usage
~~~~~~~~~~~~~~~~~
ACCEPT.C
Function: AfdDeferAccept
Protects: Endpoint->Common.VcListening.UnacceptedConnectionListHead
Synopsis: Used when deferring an accept (putting a connection back
on the endpoint's unaccepted connection queue).
Strategy: None. Deferring accepted connections is a very low
frequency operation (and is impossible in WinSock 1.1).
BIND.C
Function: AfdRestartGetAddress
Protects: Endpoint->LocalAddress[Length]
Synopsis: Used when allocating an endpoint's local address buffer
to prevent multiple processors from allocating the buffer.
Strategy: None. AfdGetAddress is only called during bind() and
getsockname() APIs. The bind() call is certainly more
interesting than getsockname(), but even bind() is only
called once per socket, so it is unlikely there would be
any benefit in tuning this.
BLKCONN.C
Function: AfdAddFreeConnection
Protects: Endpoint->Common.VcListening.FreeConnectionListHead
Synopsis: Used when adding free connections to the endpoint's
free connection queue.
Strategy: Use SLIST for free connection queue.
Function: AfdFreeConnection
Protects: Endpoint->Common.VcListening.FreeConnectionListHead
Synopsis: Used when appending a reused connection to the endpoint's
free connection queue.
Strategy: Use SLIST for free connection queue.
Function: AfdDereferenceConnection
Protects: Connection->ReferenceCount
Synopsis: Synchronizes access to reference count member.
Strategy: Use InterlockedDecrement. If updated value is now zero,
then acquire AfdSpinLock, and recheck the value for zero.
If it's still zero, do the usual dereference stuff. This
will eliminate all spinlock acquisitions on reference/
dereference except the *last* dereference.
Function: AfdGetFreeConnection
Protects: Endpoint->Common.VcListening.FreeConnectionListHead
Synopsis: Used when removing a free connection from the endpoint's
free connection queue.
Strategy: Use SLIST for free connection queue.
Function: AfdGetReturnedConnection
Protects: Endpoint->Common.VcListening.ReturnedConnectionListHead
Synopsis: Used when scanning the returned connection queue for a
specific sequence number.
Strategy: None (for now).
Function: AfdReferenceConnection
Protects: Connection->ReferenceCount
Synopsis: Synchronizes access to reference count member.
Strategy: Use InterlockedIncrement instead.
BLKENDP.C
Function: AfdFreeQueuedConnections
Protects: Endpoint->Common.VcListening.UnacceptedConnectionListHead
Synopsis: Used when puring the endpoint's unaccepted connection
queue.
Strategy: None (for now).
Function: AfdDereferenceEndpoint
Protects: Endpoint->ReferenceCount
Synopsis: Synchronizes access to reference count member.
Strategy: Use InterlockedDecrement. If updated value is now zero,
then acquire AfdSpinLock, and recheck the value for zero.
If it's still zero, do the usual dereference stuff. This
will eliminate all spinlock acquisitions on reference/
dereference except the *last* dereference.
Function: AfdReferenceEndpoint
Protects: Endpoint->ReferenceCount
Synopsis: Synchronizes access to reference count member.
Strategy: Use InterlockedIncrement instead.
CLOSE.C
Function: AfdCleanup
Protects:
Synopsis:
Strategy:
CONNECT.C
Function: AfdSetupConnectDataBuffers
Protects: Endpoint->ConnectDataBuffers
Synopsis: Used to guard connect data buffers when they're moved
from an endpoint to a connection.
Strategy: Do the "double compare" trick to avoid acquiring the
spinlock if there are no connect data buffers on the
endpoint.
Function: AfdRestartConnect
Protects: Connection->ConnectDataBuffers
Synopsis: Used to guard connect data buffers after a connect
completes.
Strategy: Do the "double compare" trick to avoid acquiring the
spinlock if there are no connect data buffers on the
connection.
DISCONN.C
Function: AfdPartialDisconnect(1)
Protects: Endpoint->DisconnectMode
Synopsis: Used to guard the disconnect mode bits when shutting
down a datagram endpoint.
Strategy: Test a Bunch-O-Bits in the endpoint, and only if
at least one of these is nonzero acquire the spinlock,
then proceed with the current tests.
Function: AfdPartialDisconnect(2)
Protects: Connection->Common.Bufferring.Receive[Expedited]BytesTaken
Synopsis: Used to guard access to the byte counters in the connection
when receives are shutdown so that the connection can be
aborted if necessary.
Strategy: None (for now).
Function: AfdDisconnectEventHandler
Protects: Connection->ConnectDataBuffers
Synopsis: Used to guard disconnect data buffers when a disconnect
indication is received.
Strategy: Do the "double compare" trick to avoid acquiring the
spinlock if there are no connect data buffers on the
connection.
Function: AfdBeginAbort
Protects: Bunch-O-Crap
Synopsis:
Strategy:
Function: AfdBeginDisconnect
Protects: Bunch-O-Crap, including disconnect buffers
Synopsis:
Strategy:
Function: AfdRestartDisconnect
Protects: DisconnectContext->DisconnectListEntry
Synopsis: Guards access to AfdDisconnectListHead
Strategy: AfdDisconnectListHead no longer used. Nuke it!
LISTEN.C
Function: AfdWaitForListen
Protects:
Synopsis:
Strategy:
Function: AfdCancelWaitForListen
Protects:
Synopsis:
Strategy:
Function: AfdConnectEventHandler
Protects:
Synopsis:
Strategy:
Function: AfdRestartAccept
Protects:
Synopsis:
Strategy:
MISC.C
Function: AfdInsertNewEndpointInList
Protects:
Synopsis:
Strategy:
Function: AfdRemoveEndpointFromList
Protects:
Synopsis:
Strategy:
Function: AfdInterlockedRemoveEntryList
Protects:
Synopsis:
Strategy:
Function: AfdGetConnectData
Protects:
Synopsis:
Strategy:
Function: AfdSetConnectData
Protects:
Synopsis:
Strategy:
Function: AfdQueueWorkItem
Protects:
Synopsis:
Strategy:
Function: AfdDoWork
Protects:
Synopsis:
Strategy:
POLL.C
Function: AfdPoll
Protects:
Synopsis:
Strategy:
Function: AfdCancelPoll
Protects:
Synopsis:
Strategy:
Function: AfdIndicatePollEvent
Protects:
Synopsis:
Strategy:
Function: AfdTimeoutPoll
Protects:
Synopsis:
Strategy:
RECEIVE.C
Function: AfdReceive
Protects:
Synopsis:
Strategy:
Function: AfdRestartReceive
Protects:
Synopsis:
Strategy:
Function: AfdReceiveEventHandler
Protects:
Synopsis:
Strategy:
Function: AfdReceiveExpeditedEventHandler
Protects:
Synopsis:
Strategy:
Function: AfdQueryReceiveInformation
Protects:
Synopsis:
Strategy:
SEND.C
Function: AfdRestartBufferSend
Protects: Connection->VcDisconnectIrp
Synopsis: Used to grab the disconnect IRP off a connection.
Strategy: Use InterlockedExchange. Will require changes to
blkconn!AfdFreeConnection.
AfdBufferSpinLock Usage
~~~~~~~~~~~~~~~~~~~~~~~
BUFFER.C
Function: AfdGetBuffer
Protects: Afd{Small|Medium|Large}BufferListHead
Synopsis: Serializes access to the various buffer lists.
Strategy: Use DaveC's SLIST instead. We'll still need the spinlock
for PPC.
Function: AfdReturnBuffer
Protects: Afd{Small|Medium|Large}BufferListHead
Synopsis: Serializes access to the various buffer lists.
Strategy: Use DaveC's SLIST instead. We'll still need the spinlock
for PPC.
Endpoint->SpinLock Usage
~~~~~~~~~~~~~~~~~~~~~~~~
ACCEPT.C
Function: AfdAcceptCore
Protects:
Synopsis:
Strategy:
BLKCONN.C
Function: AfdAddConnectedReference
Protects: Connection->ConnectedReferenceAdded
Synopsis:
Strategy:
Function: AfdDeleteConnectedReference
Protects:
Synopsis:
Strategy:
CLOSE.C
Function: AfdCleanup
Protects: Endpoint->{Receive|Peek}DatagramIrpListHead,
Endpoint->Vc{Receive|Send}IrpListHead,
Connection->CleanupBegun,
Endpoint->TransmitIrp
Synopsis:
Strategy:
CONNECT.C
Function: AfdDoDatagramConnect
Protects: Endpoint->Common.Datagram.RemoteAddress[Length]
Synopsis:
Strategy:
Function: AfdRestartConnect
Protects: Connection->ConnectedReferenceAdded
Synopsis:
Strategy:
Function: AfdEnabledFailedConnectEvent
Protects: Endpoint->EventsEnabled
Synopsis:
Strategy:
DISCONN.C
Function: AfdDisconnectEventHandler
Protects: Connection->Vc{Receive|Send}IrpListHead,
Connection->VcByteCounts
Synopsis:
Strategy:
Function: AfdBeginAbort
Protects: Connection->Vc{Receive|Send}IrpListHead,
Synopsis:
Strategy:
Function: AfdRestartAbort
Protects: Connection->Vc{Receive|Send}IrpListHead,
Synopsis:
Strategy:
EVENTSEL.C
Function: AfdEventSelect
Protects: Endpoint->EventSelectStuff
Synopsis:
Strategy:
Function: AfdEnumNetworkEvents
Protects: Endpoint->EventSelectStuff
Synopsis:
Strategy:
FASTIO.C
Function:
Protects:
Synopsis:
Strategy:
POLL.C
Function:
Protects:
Synopsis:
Strategy:
RECEIVE.C
Function:
Protects:
Synopsis:
Strategy:
RECVDG.C
Function:
Protects:
Synopsis:
Strategy:
RECVVC.C
Function:
Protects:
Synopsis:
Strategy:
SEND.C
Function:
Protects:
Synopsis:
Strategy:
TRANFILE.C
Function:
Protects:
Synopsis:
Strategy:
|