Netmap zero-copy (and some other improvements).

* Netmap supports zero copy packet transfer (on single threaded machines). * Allow --with-netmap=NETMAPDIRECTORY. * Improve some configury help messages. * Fix ToDevice bug.
wbsun · Feb 21, 2012 · 6c7c3f2 · 6c7c3f2
1 parent 6128b00
commit 6c7c3f2
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Showing 14 changed files with 305 additions and 133 deletions.
diff --git a/click-buildtool.in b/click-buildtool.in
@@ -1593,7 +1593,7 @@ EOF
   shortensyms)
      shift 1; shortensyms "$@"; exit 0;;
   --cf|--cfl|--cfla|--cflag|--cflags|--d|--de|--def|--defs)
-     echo @PROPER_INCLUDES@ @PCAP_INCLUDES@ -I@includedir@; exit 0;;
+     echo @PROPER_INCLUDES@ @PCAP_INCLUDES@ @NETMAP_INCLUDES@ -I@includedir@; exit 0;;
   --o|--ot|--oth|--othe|--other|--otherl|--otherli|--otherlib|--otherlibs)
      echo @PROPER_LIBS@ @PCAP_LIBS@ @DL_LIBS@ @SOCKET_LIBS@ @PTHREAD_LIBS@ @POSIX_CLOCK_LIBS@;
      exit 0;;

diff --git a/click-compile.in b/click-compile.in
@@ -47,7 +47,7 @@ while true; do
       --dr=*|--dri=*|--driv=*|--drive=*|--driver=*)
 	driver=`echo "$1" | sed 's/[-a-z]*=//'`; shift 1;;
       --c|--cf|--cfl|--cfla|--cflag|--cflags|--de|--def|--defs)
-	echo @PROPER_INCLUDES@ @PCAP_INCLUDES@ -I$includedir
+	echo @PROPER_INCLUDES@ @PCAP_INCLUDES@ @NETMAP_INCLUDES@ -I$includedir
 	exit=y; shift 1;;
       --l|--li|--lib|--libs)
 	echo -L$libdir -lclick @PROPER_LIBS@ @PCAP_LIBS@ @DL_LIBS@ @SOCKET_LIBS@ @PTHREAD_LIBS@ @POSIX_CLOCK_LIBS@

diff --git a/configure b/configure
@@ -640,6 +640,7 @@ EXPAT_INCLUDES
 XML2CLICK
 PROPER_LIBS
 PROPER_INCLUDES
+NETMAP_INCLUDES
 PCAP_LIBS
 PCAP_INCLUDES
 TOOL_TARGETS
@@ -809,6 +810,7 @@ enable_dmalloc
 enable_valgrind
 enable_schedule_debugging
 enable_intel_cpu
+with_netmap
 with_proper
 with_expat
 '
@@ -1442,11 +1444,13 @@ Optional Features:
   --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
   --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]
   --disable-userlevel     disable user-level driver
-    --enable-user-multithread support userlevel multithreading
-    --enable-select=[select|poll|kqueue] set file descriptor wait mechanism
-    --disable-select          do not use select()
-    --disable-poll            do not use poll()
-    --disable-kqueue          do not use kqueue()
+    --enable-user-multithread
+                          support userlevel multithreading
+    --enable-select=[select|poll|kqueue]
+                          set file descriptor wait mechanism
+    --disable-select      do not use select()
+    --disable-poll        do not use poll()
+    --disable-kqueue      do not use kqueue()
   --disable-linuxmodule   disable Linux kernel driver
     --disable-fixincludes     do not patch Linux kernel headers for C++
     --enable-multithread      support kernel multithreading
@@ -1500,6 +1504,7 @@ Optional Packages:
   --with-linux-map[=FILE] filename for Linux System.map [LINUXDIR/System.map]
   --with-freebsd[=SRC,INC] FreeBSD source code is in SRC [/usr/src/sys],
                           include directory is INC [/usr/include]
+  --with-netmap           enable netmap [no]
   --with-proper[=PREFIX]  use PlanetLab Proper library (optional)
   --with-expat[=PREFIX]   locate expat XML library (optional)
 
@@ -6194,7 +6199,7 @@ fi
 if test "${enable_select+set}" = set; then :
   enableval=$enable_select; :
 else
-  enable_select='select poll kqueue'
+  enable_select="select poll kqueue"
 fi
 
 # Check whether --enable-poll was given.
@@ -7361,7 +7366,7 @@ else
 
 	    	    ac_cv_endian=0
 	    cat > conftest.$ac_ext <<EOF
-#line 7364 "configure"
+#line 7369 "configure"
 #include "confdefs.h"
 #include <$endian_hdr>
 #ifdef __BYTE_ORDER
@@ -10162,14 +10167,31 @@ done
     fi
 
 
+
+# Check whether --with-netmap was given.
+if test "${with_netmap+set}" = set; then :
+  withval=$with_netmap; use_netmap=$withval
+else
+  use_netmap=no
+fi
+
+
+    if test "$use_netmap" != "yes" -a "$use_netmap" != "no"; then
+	if test "${NETMAP_INCLUDES-NO}" != NO; then
+	    :
+	elif test -f "$use_netmap/net/netmap.h"; then
+	    NETMAP_INCLUDES="-I$use_netmap"
+	elif test -f "$use_netmap/include/net/netmap.h"; then
+	    NETMAP_INCLUDES="-I$use_netmap/include"
+	fi
+    fi
+    saveflags="$CPPFLAGS"
+    CPPFLAGS="$saveflags $NETMAP_INCLUDES"
+
     HAVE_NETMAP=no
     { $as_echo "$as_me:${as_lineno-$LINENO}: checking for net/netmap.h" >&5
 $as_echo_n "checking for net/netmap.h... " >&6; }
-if ${ac_cv_net_netmap_header_path+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-
-	cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+    cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 #include <net/netmap.h>
 _ACEOF
@@ -10179,9 +10201,9 @@ else
   ac_cv_net_netmap_header_path="not found"
 fi
 rm -f conftest.err conftest.i conftest.$ac_ext
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_net_netmap_header_path" >&5
+    { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_net_netmap_header_path" >&5
 $as_echo "$ac_cv_net_netmap_header_path" >&6; }
+
     if test "$ac_cv_net_netmap_header_path" = "found"; then
 	HAVE_NETMAP=yes
     fi
@@ -10209,12 +10231,14 @@ $as_echo "$ac_cv_working_net_netmap_h" >&6; }
 	test "$ac_cv_working_net_netmap_h" != yes && HAVE_NETMAP=
     fi
 
-    if test "$HAVE_NETMAP" = yes; then
+    CPPFLAGS="$saveflags"
+    if test "$HAVE_NETMAP" = yes -a "$use_netmap" != no; then
 
 $as_echo "#define HAVE_NET_NETMAP_H 1" >>confdefs.h
 
     fi
 
+
     if test "$HAVE_PCAP" != yes -a "$HAVE_NETMAP" != yes -a "$ac_cv_under_linux" != yes; then
 	{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING:
 =========================================
@@ -12424,6 +12448,10 @@ if test $ac_have_linux_kernel = y; then
     fi
 fi
 
+if test "x$HAVE_NETMAP" = xyes; then
+    provisions="$provisions netmap"
+fi
+
 if test "x$HAVE_PCAP" = xyes; then
     provisions="$provisions pcap"
 fi

diff --git a/configure.in b/configure.in
@@ -65,9 +65,13 @@ dnl
 
 dnl userlevel driver and features
 
-AC_ARG_ENABLE(userlevel, [  --disable-userlevel     disable user-level driver], :, enable_userlevel=yes)
+AC_ARG_ENABLE([userlevel],
+    [AS_HELP_STRING([--disable-userlevel], [disable user-level driver])],
+    [:], [enable_userlevel=yes])
 
-AC_ARG_ENABLE(user-multithread, [[    --enable-user-multithread support userlevel multithreading]], :, [enable_user_multithread=no])
+AC_ARG_ENABLE([user-multithread],
+    [AS_HELP_STRING([  --enable-user-multithread], [support userlevel multithreading])],
+    [:], [enable_user_multithread=no])
 
 PTHREAD_LIBS=""
 AC_SUBST(PTHREAD_LIBS)
@@ -93,10 +97,16 @@ Can't find -lpthread and/or <pthread.h>, so I can't compile with
     LIBS="$SAVE_LIBS"
 fi
 
-AC_ARG_ENABLE([select], [    --enable-select=[[select|poll|kqueue]] set file descriptor wait mechanism
-    --disable-select          do not use select()], [:], [enable_select='select poll kqueue'])
-AC_ARG_ENABLE([poll], [    --disable-poll            do not use poll()], [:], [enable_poll=yes])
-AC_ARG_ENABLE([kqueue], [    --disable-kqueue          do not use kqueue()], [:], [enable_kqueue=yes])
+AC_ARG_ENABLE([select],
+    [AS_HELP_STRING([  --enable-select=[[select|poll|kqueue]]], [set file descriptor wait mechanism])
+AS_HELP_STRING([  --disable-select], [do not use select()])],
+    [:], [enable_select="select poll kqueue"])
+AC_ARG_ENABLE([poll],
+    [AS_HELP_STRING([  --disable-poll], [do not use poll()])],
+    [:], [enable_poll=yes])
+AC_ARG_ENABLE([kqueue],
+    [AS_HELP_STRING([  --disable-kqueue], [do not use kqueue()])],
+    [:], [enable_kqueue=yes])
 
 if test "$enable_select" = yes; then
     enable_select='select poll kqueue'
@@ -1746,6 +1756,11 @@ if test $ac_have_linux_kernel = y; then
     fi
 fi
 
+dnl add 'netmap' if netmap support is available
+if test "x$HAVE_NETMAP" = xyes; then
+    provisions="$provisions netmap"
+fi
+
 dnl add 'pcap' if libpcap is available
 if test "x$HAVE_PCAP" = xyes; then
     provisions="$provisions pcap"

diff --git a/elements/userlevel/fromdevice.cc b/elements/userlevel/fromdevice.cc
@@ -7,6 +7,7 @@
  * Copyright (c) 2001 International Computer Science Institute
  * Copyright (c) 2005-2007 Regents of the University of California
  * Copyright (c) 2011 Meraki, Inc.
+ * Copyright (c) 2012 Eddie Kohler
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -272,56 +273,6 @@ FromDevice::open_pcap(String ifname, int snaplen, bool promisc,
 }
 #endif
 
-#if FROMDEVICE_ALLOW_NETMAP
-int
-FromDevice::netmap_type::open(const String &ifname,
-			      bool always_error, ErrorHandler *errh)
-{
-    ErrorHandler *initial_errh = always_error ? errh : ErrorHandler::silent_handler();
-
-    int fd = ::open("/dev/netmap", O_RDWR);
-    if (fd < 0) {
-	initial_errh->error("/dev/netmap: %s", strerror(errno));
-	return -1;
-    }
-
-    struct nmreq req;
-    memset(&req, 0, sizeof(req));
-    strncpy(req.nr_name, ifname.c_str(), sizeof(req.nr_name));
-    req.nr_ringid = 0;
-    int r;
-    if ((r = ioctl(fd, NIOCGINFO, &req))) {
-	initial_errh->error("netmap %s: %s", ifname.c_str(), strerror(errno));
-    error:
-	close(fd);
-	return -1;
-    }
-
-    memsize = req.nr_memsize;
-    if ((r = ioctl(fd, NIOCREGIF, &req))) {
-	errh->error("netmap register %s: %s", ifname.c_str(), strerror(errno));
-	goto error;
-    }
-
-    mem = (char *) mmap(0, memsize, PROT_WRITE | PROT_READ,
-			MAP_SHARED, fd, 0);
-    if (mem == MAP_FAILED) {
-	errh->error("netmap allocate %s: %s", ifname.c_str(), strerror(errno));
-	mem = 0;
-	goto error;
-    }
-
-    nifp = NETMAP_IF(mem, req.nr_offset);
-    ring_begin = 0;
-    ring_end = req.nr_numrings;
-
-    // XXX timestamp off
-    for (unsigned i = ring_begin; i != ring_end; ++i)
-	NETMAP_RXRING(nifp, i)->flags = NR_TIMESTAMP;
-    return fd;
-}
-#endif
-
 int
 FromDevice::initialize(ErrorHandler *errh)
 {
@@ -443,12 +394,8 @@ FromDevice::cleanup(CleanupStage stage)
     if (stage >= CLEANUP_INITIALIZED && !_sniffer)
 	KernelFilter::device_filter(_ifname, false, ErrorHandler::default_handler());
 #if FROMDEVICE_ALLOW_NETMAP
-    if (_fd >= 0 && _method == method_netmap) {
-	munmap(_netmap.mem, _netmap.memsize);
-	ioctl(_fd, NIOCUNREGIF, (struct nmreq *) 0);
-	close(_fd);
-	_netmap.mem = 0;
-    }
+    if (_fd >= 0 && _method == method_netmap)
+	_netmap.close(_fd);
 #endif
 #if FROMDEVICE_ALLOW_LINUX
     if (_fd >= 0 && _method == method_linux) {
@@ -469,11 +416,8 @@ FromDevice::cleanup(CleanupStage stage)
 
 #if FROMDEVICE_ALLOW_PCAP || FROMDEVICE_ALLOW_NETMAP
 void
-FromDevice::emit_packet_data(const unsigned char *buf, int len, int fulllen,
-			     const Timestamp &ts)
+FromDevice::emit_packet(WritablePacket *p, int extra_len, const Timestamp &ts)
 {
-    WritablePacket *p = Packet::make(_headroom, buf, len, 0);
-
     // set packet type annotation
     if (p->data()[0] & 1) {
 	if (EtherAddress::is_broadcast(p->data()))
@@ -485,7 +429,7 @@ FromDevice::emit_packet_data(const unsigned char *buf, int len, int fulllen,
     // set annotations
     p->set_timestamp_anno(ts);
     p->set_mac_header(p->data());
-    SET_EXTRA_LENGTH_ANNO(p, fulllen - len);
+    SET_EXTRA_LENGTH_ANNO(p, extra_len);
 
     if (!_force_ip || fake_pcap_force_ip(p, _datalink))
 	output(0).push(p);
@@ -503,8 +447,9 @@ FromDevice_get_packet(u_char* clientdata,
 		      const u_char* data)
 {
     FromDevice *fd = (FromDevice *) clientdata;
-    fd->emit_packet_data(data, pkthdr->caplen, pkthdr->len,
-			 Timestamp::make_usec(pkthdr->ts.tv_sec, pkthdr->ts.tv_usec));
+    WritablePacket *p = Packet::make(fd->_headroom, data, pkthdr->caplen, 0);
+    fd->emit_packet(p, pkthdr->len - pkthdr->caplen,
+		    Timestamp::make_usec(pkthdr->ts.tv_sec, pkthdr->ts.tv_usec));
 }
 }
 CLICK_DECLS
@@ -517,18 +462,38 @@ FromDevice::netmap_dispatch()
     int n = 0;
     for (unsigned ri = _netmap.ring_begin; ri != _netmap.ring_end; ++ri) {
 	struct netmap_ring *ring = NETMAP_RXRING(_netmap.nifp, ri);
+	//click_chatter("netmap dispatch %s %u %u %u %u", _ifname.c_str(), ri, ring->cur, ring->reserved, ring->avail);
+
+	while (ring->reserved > 0 && NetmapInfo::refill(ring))
+	    /* click_chatter("Refilled") */;
+
 	if (ring->avail == 0)
 	    continue;
+
+	int nzcopy = (int) (ring->num_slots / 2) - (int) ring->reserved;
+
 	while (n != _burst && ring->avail > 0) {
-	    unsigned i = ring->cur;
-	    unsigned buf_idx = ring->slot[i].buf_idx;
+	    unsigned cur = ring->cur;
+	    unsigned buf_idx = ring->slot[cur].buf_idx;
 	    if (buf_idx < 2)
 		break;
 	    unsigned char *buf = (unsigned char *) NETMAP_BUF(ring, buf_idx);
-	    emit_packet_data(buf, ring->slot[i].len, ring->slot[i].len, ring->ts);
-	    ring->cur = NETMAP_RING_NEXT(ring, i);
-	    ring->avail--;
-	    n++;
+
+	    WritablePacket *p;
+	    if (nzcopy > 0) {
+		p = Packet::make(buf, ring->slot[cur].len, NetmapInfo::buffer_destructor);
+		++ring->reserved;
+		--nzcopy;
+	    } else {
+		p = Packet::make(_headroom, buf, ring->slot[cur].len, 0);
+		unsigned res1idx = NETMAP_RING_FIRST_RESERVED(ring);
+		ring->slot[res1idx].buf_idx = buf_idx;
+	    }
+	    ring->cur = NETMAP_RING_NEXT(ring, ring->cur);
+	    --ring->avail;
+	    ++n;
+
+	    emit_packet(p, 0, ring->ts);
 	}
     }
     return n;
@@ -671,5 +636,5 @@ FromDevice::add_handlers()
 }
 
 CLICK_ENDDECLS
-ELEMENT_REQUIRES(userlevel FakePcap KernelFilter)
+ELEMENT_REQUIRES(userlevel FakePcap KernelFilter NetmapInfo)
 EXPORT_ELEMENT(FromDevice)