src/comm/AcceptLimiter.cc

   1 #include "squid.h"
   2 #include "comm/AcceptLimiter.h"
   3 #include "comm/Connection.h"
   4 #include "comm/TcpAcceptor.h"
   5 #include "fde.h"
   6
   7 Comm::AcceptLimiter Comm::AcceptLimiter::Instance_;
   8
   9 Comm::AcceptLimiter &Comm::AcceptLimiter::Instance()
  10 {
  11     return Instance_;
  12 }
  13
  14 void
  15 Comm::AcceptLimiter::defer(Comm::TcpAcceptor *afd)
  16 {
  17     afd->isLimited++;
  18     debugs(5, 5, HERE << afd->conn << " x" << afd->isLimited);
  19     deferred.push_back(afd);
  20 }
  21
  22 void
  23 Comm::AcceptLimiter::removeDead(const Comm::TcpAcceptor *afd)
  24 {
  25     for (unsigned int i = 0; i < deferred.size() && afd->isLimited > 0; i++) {
  26         if (deferred[i] == afd) {
  27             deferred[i]->isLimited--;
  28             deferred[i] = NULL; // fast. kick() will skip empty entries later.
  29             debugs(5, 5, HERE << afd->conn << " x" << afd->isLimited);
  30         }
  31     }
  32 }
  33
  34 void
  35 Comm::AcceptLimiter::kick()
  36 {
  37     // TODO: this could be optimized further with an iterator to search
  38     //       looking for first non-NULL, followed by dumping the first N
  39     //       with only one shift()/pop_front operation
  40
  41     debugs(5, 5, HERE << " size=" << deferred.size());
  42     while (deferred.size() > 0 && fdNFree() >= RESERVED_FD) {
  43         /* NP: shift() is equivalent to pop_front(). Giving us a FIFO queue. */
  44         TcpAcceptor *temp = deferred.shift();
  45         if (temp != NULL) {
  46             debugs(5, 5, HERE << " doing one.");
  47             temp->isLimited--;
  48             temp->acceptNext();
  49             break;
  50         }
  51     }
  52 }