XRootD
XrdPollPoll Class Reference

#include <XrdPollPoll.hh>

+ Inheritance diagram for XrdPollPoll:
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Public Member Functions

 XrdPollPoll (struct pollfd *pp, int numfd)
 
 ~XrdPollPoll ()
 
void Disable (XrdPollInfo &pInfo, const char *etxt=0)
 
int Enable (XrdPollInfo &pInfo)
 
void Start (XrdSysSemaphore *syncp, int &rc)
 

Protected Member Functions

void doDetach (int pti)
 
void Exclude (XrdPollInfo &pInfo)
 
int Include (XrdPollInfo &pInfo)
 

Detailed Description

Definition at line 38 of file XrdPollPoll.hh.

Constructor & Destructor Documentation

◆ XrdPollPoll()

XrdPollPoll::XrdPollPoll ( struct pollfd *  pp,
int  numfd 
)

Definition at line 67 of file XrdPollPoll.icc.

68 {
69 
70 // Initialize the standard stuff
71 //
72  PollTab = pp;
73  PollTNum= 0;
74  PollQ = 0;
75  maxent = numfd;
76 }

◆ ~XrdPollPoll()

XrdPollPoll::~XrdPollPoll ( )

Definition at line 82 of file XrdPollPoll.icc.

83 {
84  if (PollTab) free(PollTab);
85 }

Member Function Documentation

◆ Disable()

void XrdPollPoll::Disable ( XrdPollInfo pInfo,
const char *  etxt = 0 
)
virtual

Implements XrdPoll.

Definition at line 135 of file XrdPollPoll.icc.

136 {
137  XrdSysSemaphore mySem(0);
138  PipeData cmdbuff[2];
139  int myerrno = 0;
140 
141 // Check if this link is in the pollQ. If so, remove it.
142 //
143  if (pInfo.inQ) dqLink(&pInfo);
144 
145 // Simply return if the link is already disabled
146 //
147  if (!pInfo.isEnabled) return;
148 
149 // Trace this event
150 //
151  TRACEI(POLL, "Poller " <<PID <<" async disabling link FD " <<pInfo.FD);
152 
153 // Send a disable request to the poller thread handling this link. We need to
154 // wait until the operation is actually completed before returning.
155 //
156  memset(&cmdbuff, 0, sizeof(cmdbuff));
157  cmdbuff[0].req = PipeData::DiFD;
158  cmdbuff[0].Parms.Arg.fd = pInfo.FD;
159  cmdbuff[0].Parms.Arg.ent = pInfo.PollEnt - PollTab;
160  cmdbuff[1].req = PipeData::Post;
161  cmdbuff[1].Parms.theSem = &mySem;
162  PollPipe.Lock();
163  if (write(CmdFD, &cmdbuff, sizeof(cmdbuff)) < 0) myerrno = errno;
164  PollPipe.UnLock();
165 
166 // Verify that all went well and if termination wanted, terminate the link
167 //
168  if (myerrno) Log.Emsg("Poll", myerrno, "disable link", pInfo.Link.ID);
169  else {mySem.Wait();
170  if (etxt && Finish(pInfo, etxt))
171  Sched.Schedule((XrdJob *)&pInfo.Link);
172  }
173 }
ssize_t write(int fildes, const void *buf, size_t nbyte)
#define TRACEI(act, x)
Definition: XrdTrace.hh:66
Definition: XrdJob.hh:43
struct pollfd * PollEnt
Definition: XrdPollInfo.hh:42
XrdLink & Link
Definition: XrdPollInfo.hh:41
bool isEnabled
Definition: XrdPollInfo.hh:46
int PID
Definition: XrdPoll.hh:82
XrdSysMutex PollPipe
Definition: XrdPoll.hh:115
static int Finish(XrdPollInfo &pInfo, const char *etxt=0)
Definition: XrdPoll.cc:204
int CmdFD
Definition: XrdPoll.hh:117
void Schedule(XrdJob *jp)
int Emsg(const char *esfx, int ecode, const char *text1, const char *text2=0)
Definition: XrdSysError.cc:95
XrdSysError Log
Definition: XrdConfig.cc:112
XrdScheduler Sched
Definition: XrdLinkCtl.cc:54

References XrdPoll::CmdFD, XrdPoll::PipeData::DiFD, XrdSysError::Emsg(), XrdPollInfo::FD, XrdPoll::Finish(), XrdLink::ID, XrdPollInfo::inQ, XrdPollInfo::isEnabled, XrdPollInfo::Link, XrdSysMutex::Lock(), XrdGlobal::Log, XrdPoll::PipeData::Parms, XrdPoll::PID, XrdPollInfo::PollEnt, XrdPoll::PollPipe, XrdPoll::PipeData::Post, XrdPoll::PipeData::req, XrdGlobal::Sched, XrdScheduler::Schedule(), TRACEI, XrdSysMutex::UnLock(), XrdSysSemaphore::Wait(), and write().

Referenced by Exclude().

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◆ doDetach()

void XrdPollPoll::doDetach ( int  pti)
protected

Definition at line 358 of file XrdPollPoll.icc.

359 {
360  int lastent;
361 
362 // Get some starting values
363 //
364  if ((lastent = PollTNum-1) < 0)
365  {Log.Emsg("Poll","Underflow during detach"); abort();}
366 
367  if (pti == lastent)
368  do {PollTNum--;} while(PollTNum && PollTab[PollTNum-1].fd == -1);
369 }

References XrdSysError::Emsg(), and XrdGlobal::Log.

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◆ Enable()

int XrdPollPoll::Enable ( XrdPollInfo pInfo)
virtual

Implements XrdPoll.

Definition at line 179 of file XrdPollPoll.icc.

180 {
181  PipeData cmdbuff;
182  int myerrno = 0;
183 
184 // Simply return if the link is already enabled
185 //
186  if (pInfo.isEnabled) return 1;
187 
188 // Add this link element to the queue
189 //
190  PollMutex.Lock();
191  pInfo.Next = PollQ;
192  PollQ = &pInfo;
193  pInfo.inQ = true;
194  PollMutex.UnLock();
195 
196 // Send an enable request to the poller thread handling this link
197 //
198  TRACEI(POLL, "sending poller " <<PID <<" enable for link " <<pInfo.FD);
199  cmdbuff.req = PipeData::EnFD;
200  cmdbuff.Parms.Arg.fd = pInfo.FD;
201  cmdbuff.Parms.Arg.ent = pInfo.PollEnt - PollTab;
202  PollPipe.Lock();
203  if (write(CmdFD, &cmdbuff, sizeof(cmdbuff)) < 0) myerrno = errno;
204  PollPipe.UnLock();
205 
206 // Verify that all went well. Note that the link stays in the pollQ.
207 //
208  if (myerrno)
209  {Log.Emsg("Poll", myerrno, "enable link", pInfo.Link.ID); return 0;}
210 
211 // All done
212 //
213  return 1;
214 }
XrdPollInfo * Next
Definition: XrdPollInfo.hh:40

References XrdPoll::CmdFD, XrdSysError::Emsg(), XrdPoll::PipeData::EnFD, XrdPollInfo::FD, XrdLink::ID, XrdPollInfo::inQ, XrdPollInfo::isEnabled, XrdPollInfo::Link, XrdSysMutex::Lock(), XrdGlobal::Log, XrdPollInfo::Next, XrdPoll::PipeData::Parms, XrdPoll::PID, XrdPollInfo::PollEnt, XrdPoll::PollPipe, XrdPoll::PipeData::req, TRACEI, XrdSysMutex::UnLock(), and write().

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◆ Exclude()

void XrdPollPoll::Exclude ( XrdPollInfo pInfo)
protectedvirtual

Implements XrdPoll.

Definition at line 220 of file XrdPollPoll.icc.

221 {
222  XrdSysSemaphore mySem(0);
223  PipeData cmdbuff[2];
224  int myerrno = 0;
225 
226 // Make sure this link is not enabled
227 //
228  if (pInfo.isEnabled)
229  {Log.Emsg("Poll", "Detach of enabled link", pInfo.Link.ID);
230  Disable(pInfo);
231  }
232  else if (pInfo.inQ) dqLink(&pInfo);
233 
234 // Send a deatch request to the poller thread handling this link
235 //
236  TRACEI(POLL, "sending poller " <<PID <<" detach for link " <<pInfo.FD);
237  cmdbuff[0].req = PipeData::RmFD;
238  cmdbuff[0].Parms.Arg.fd = pInfo.FD;
239  cmdbuff[0].Parms.Arg.ent = pInfo.PollEnt - PollTab;
240  cmdbuff[1].req = PipeData::Post;
241  cmdbuff[1].Parms.theSem = &mySem;
242  PollPipe.Lock();
243  if (write(CmdFD, &cmdbuff, sizeof(cmdbuff)) < 0) myerrno = errno;
244  PollPipe.UnLock();
245 
246 // Verify that all went well and if termination wanted, terminate the link
247 //
248  if (myerrno) Log.Emsg("Poll", myerrno, "detach link", pInfo.Link.ID);
249  else mySem.Wait();
250 }
void Disable(XrdPollInfo &pInfo, const char *etxt=0)

References XrdPoll::CmdFD, Disable(), XrdSysError::Emsg(), XrdPollInfo::FD, XrdLink::ID, XrdPollInfo::inQ, XrdPollInfo::isEnabled, XrdPollInfo::Link, XrdSysMutex::Lock(), XrdGlobal::Log, XrdPoll::PipeData::Parms, XrdPoll::PID, XrdPollInfo::PollEnt, XrdPoll::PollPipe, XrdPoll::PipeData::Post, XrdPoll::PipeData::req, XrdPoll::PipeData::RmFD, TRACEI, XrdSysMutex::UnLock(), XrdSysSemaphore::Wait(), and write().

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◆ Include()

int XrdPollPoll::Include ( XrdPollInfo pInfo)
protectedvirtual

Implements XrdPoll.

Definition at line 91 of file XrdPollPoll.icc.

92 {
93  struct pollfd *pfd;
94  int ptnum;
95 
96 // Lock down the poll data structure
97 //
98  PollMutex.Lock();
99 
100 // Get the next entry to be used
101 //
102  ptnum = 0;
103  while((ptnum < PollTNum) && (PollTab[ptnum].fd != -1)) ptnum++;
104 
105 // Make sure we have enough table entries to add this link
106 //
107  if (ptnum > maxent)
108  {Log.Emsg("Attach","Attach",pInfo.Link.ID,"failed; poll table overflow.");
109  PollMutex.UnLock();
110  return 0;
111  }
112 
113 // Initialize the polltable entry
114 //
115  pfd = &(PollTab[ptnum]);
116  pfd->fd = -pInfo.FD;
117  pfd->events = POLLIN | POLLRDNORM;
118  pfd->revents = 0;
119 
120 // Record relevant information in the link
121 //
122  pInfo.PollEnt = pfd;
123  if (ptnum == PollTNum) PollTNum++;
124 
125 // All done
126 //
127  PollMutex.UnLock();
128  return 1;
129 }

References XrdSysError::Emsg(), XrdPollInfo::FD, XrdLink::ID, XrdPollInfo::Link, XrdSysMutex::Lock(), XrdGlobal::Log, XrdPollInfo::PollEnt, and XrdSysMutex::UnLock().

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◆ Start()

void XrdPollPoll::Start ( XrdSysSemaphore syncp,
int &  rc 
)
virtual

Implements XrdPoll.

Definition at line 256 of file XrdPollPoll.icc.

257 {
258  int numpolled, num2sched;
259  XrdJob *jfirst, *jlast;
260  XrdPollInfo *plp, *nlp, *pInfo;
261  XrdLink *lp;
262  short pollevents;
263  const short pollOK = POLLIN | POLLRDNORM;
264 
265 // Set up he first entry in the poll table to be our communications port
266 //
267  PollTab[0].fd = ReqFD;
268  PollTab[0].events = pollOK;
269  PollTab[0].revents = 0;
270  PollTNum = 1;
271 
272 // Signal the caller to continue
273 //
274  retcode = 0;
275  syncsem->Post();
276 
277 // Now do the main poll loop
278 //
279  std::vector<struct pollfd> PollTabCopy;
280  do {// Duplicate the polling table so we don't need to hold the PollMutex
281  // while we are sleeping in the poll()
282  PollMutex.Lock();
283  PollTabCopy.resize(PollTNum);
284  memcpy(PollTabCopy.data(), PollTab, sizeof(struct pollfd) * PollTNum);
285  PollMutex.UnLock();
286 
287  do {numpolled = poll(PollTabCopy.data(), PollTabCopy.size(), -1);}
288  while(numpolled < 0 && (errno == EAGAIN || errno == EINTR));
289 
290  // Check if we had a polling error
291  //
292  if (numpolled < 0)
293  {if (errno != EINTR) Restart(errno);
294  else numInterrupts++;
295  continue;
296  }
297  numEvents += numpolled;
298 
299  // Note this thread is the only one that writes directly to the poll
300  // table (everything else is a read). Hence, it's OK to assume that
301  // the table after the poll() is unchanged and we can write back the
302  // revents field.
303  PollMutex.Lock();
304  for (size_t idx=0; idx<PollTabCopy.size(); idx++)
305  PollTab[idx].revents = PollTabCopy[idx].revents;
306 
307  // Check out base poll table entry, we can do this without a lock
308  //
309  if (PollTab[0].revents & pollOK)
310  {PollMutex.UnLock();
311  doRequests(numpolled);
312  if (--numpolled <= 0) continue;
313  PollMutex.Lock();
314  }
315 
316  // Checkout which links must be dispatched (do this locked)
317  //
318  plp = 0; nlp = PollQ; jfirst = jlast = 0; num2sched = 0;
319  while ((pInfo = nlp) && numpolled > 0)
320  {if ((pollevents = pInfo->PollEnt->revents))
321  {pInfo->PollEnt->fd = -pInfo->PollEnt->fd;
322  if (plp) nlp = plp->Next = pInfo->Next;
323  else nlp = PollQ = pInfo->Next;
324  numpolled--; pInfo->inQ = false;
325  if (!(pollevents & pollOK))
326  Finish(*pInfo, Poll2Text(pollevents));
327  lp = &(pInfo->Link);
328  if (!(pInfo->isEnabled))
329  Log.Emsg("Poll", "Disabled event occurred for", lp->ID);
330  else {pInfo->isEnabled = false;
331  lp->NextJob = jfirst; jfirst = (XrdJob *)lp;
332  if (!jlast) jlast=(XrdJob *)lp;
333  num2sched++;
334  continue;
335  }
336  }
337  plp = pInfo; nlp = pInfo->Next;
338  }
339  if (numpolled) Recover(numpolled);
340  PollMutex.UnLock();
341 
342  // Schedule the polled links
343  //
344  if (num2sched == 1) Sched.Schedule(jfirst);
345  else if (num2sched) Sched.Schedule(num2sched, jfirst, jlast);
346  } while(1);
347 }
XrdJob * NextJob
Definition: XrdJob.hh:46
int numInterrupts
Definition: XrdPoll.hh:134
int ReqFD
Definition: XrdPoll.hh:118
int numEvents
Definition: XrdPoll.hh:133
static char * Poll2Text(short events)
Definition: XrdPoll.cc:272

References XrdSysError::Emsg(), XrdPoll::Finish(), XrdLink::ID, XrdPollInfo::inQ, XrdPollInfo::isEnabled, XrdPollInfo::Link, XrdSysMutex::Lock(), XrdGlobal::Log, XrdPollInfo::Next, XrdJob::NextJob, XrdPoll::numEvents, XrdPoll::numInterrupts, XrdPoll::Poll2Text(), XrdPollInfo::PollEnt, XrdSysSemaphore::Post(), XrdPoll::ReqFD, XrdGlobal::Sched, XrdScheduler::Schedule(), and XrdSysMutex::UnLock().

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The documentation for this class was generated from the following files: