Changeset d48008d for lib

Timestamp:

05/16/10 21:34:48 (11 years ago)

Author:

Perry Lorier <perry@…>

Branches:

4.0.1-hotfixes, cachetimestamps, develop, dpdk-ndag, etsilive, getfragoff, help, libtrace4, master, ndag_format, pfring, rc-4.0.1, rc-4.0.2, rc-4.0.3, rc-4.0.4, ringdecrementfix, ringperformance, ringtimestampfixes

Children:

c3f597e

Parents:

9da93dc

Message:

Add JITting of BPF bytecode using LLVM

Location:

lib

Files:

• Makefile.am (modified) (4 diffs)
• bpf-jit/bpf-jit.cc (added)
• bpf-jit/bpf-jit.h (added)
• bpf-jit/bpf-opcodes.c (added)
• trace.c (modified) (4 diffs)

lib/Makefile.am

@@ -3 +3 @@
 
 AM_CFLAGS=@LIBCFLAGS@
+AM_CXXFLAGS=@LIBCXXFLAGS@
 
 extra_DIST = format_template.c
@@ -46 +47 @@
 EXTRA_DIST=format_dag24.c format_dag25.c
 
+if HAVE_LLVM
+BPFJITSOURCE=bpf-jit/bpf-jit.cc 
+else
+BPFJITSOURCE=
+endif
+
+
 libtrace_la_SOURCES = trace.c common.h \
                 format_erf.c format_pcap.c format_legacy.c \
@@ -56 +64 @@
                 protocols_transport.c protocols.h \
                 $(DAGSOURCE) format_erf.h \
+                $(BPFJITSOURCE) \
                 $(LIBTRACEIO_ZLIB) $(LIBTRACEIO_BZLIB) $(LIBTRACEIO_LZO) \
                 ior-peek.c ior-stdio.c ior-thread.c \
@@ -74 +83 @@
 dagopts.c:
         cp @DAG_TOOLS_DIR@/dagopts.c .
+
+if HAVE_LLVM
+# Rules to build the llvm .cc file from a C description of each opcode.
+bpf-jit/bpf-opcodes.llvm.bc: bpf-jit/bpf-opcodes.c
+        `$(LLVM_CONFIG) --bindir`/llvm-gcc -std=c99 -c -O0 -emit-llvm $< -o $@
+
+bpf-jit/bpf-opcodes.llvm.cc: bpf-jit/bpf-opcodes.llvm.bc
+        `$(LLVM_CONFIG) --bindir`/llc -f -march=cpp -cppgen=module $< -o $@
+
+bpf-jit/bpf-jit.cc: bpf-jit/bpf-opcodes.llvm.cc
+
+EXTRA_DIST+=bpf-jit/bpf-opcodes.c
+BUILT_SOURCES=bpf-jit/bpf-opcodes.llvm.cc
+endif
+CLEANFILES=bpf-jit/bpf-opcodes.llvm.cc bpf-jit/bpf-opcodes.llvm.bc

lib/trace.c

@@ -1103 +1103 @@
         filter->filter.bf_len = bf_len;
         filter->filterstring = NULL;
+        filter->jitfilter = NULL;
         /* "flag" indicates that the filter member is valid */
         filter->flag = 1; 
@@ -1119 +1120 @@
                                 malloc(sizeof(libtrace_filter_t));
         filter->filterstring = strdup(filterstring);
+        filter->jitfilter = NULL;
         filter->flag = 0;
         return filter;
@@ -1133 +1135 @@
         if (filter->flag)
                 pcap_freecode(&filter->filter);
+#ifdef HAVE_LLVM
+        if (filter->jitfilter) 
+                destroy_program(filter->jitfilter);
+#endif
         free(filter);
 #else
@@ -1257 +1263 @@
         }
 
+        /* If we're jitting, we may need to JIT the BPF code now too */
+#if HAVE_LLVM
+        if (!filter->jitfilter) {
+                filter->jitfilter = compile_program(filter->filter.bf_insns, filter->filter.bf_len);
+        }
+#endif
+
         assert(filter->flag);
+        /* Now execute the filter */
+#if HAVE_LLVM
+        ret=filter->jitfilter->bpf_run((unsigned char *)linkptr, clen);
+#else
         ret=bpf_filter(filter->filter.bf_insns,(u_char*)linkptr,(unsigned int)clen,(unsigned int)clen);
+#endif
 
         /* If we copied the packet earlier, make sure that we free it */