samples: bpf: add bpf_perf_event_output example
Performance test and example of bpf_perf_event_output().
kprobe is attached to sys_write() and trivial bpf program streams
pid+cookie into userspace via PERF_COUNT_SW_BPF_OUTPUT event.
Usage:
$ sudo ./bld_x64/samples/bpf/trace_output
recv 2968913 events per sec
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 63e7d50..b305145 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -13,6 +13,7 @@
hostprogs-y += tracex4
hostprogs-y += tracex5
hostprogs-y += tracex6
+hostprogs-y += trace_output
hostprogs-y += lathist
test_verifier-objs := test_verifier.o libbpf.o
@@ -27,6 +28,7 @@
tracex4-objs := bpf_load.o libbpf.o tracex4_user.o
tracex5-objs := bpf_load.o libbpf.o tracex5_user.o
tracex6-objs := bpf_load.o libbpf.o tracex6_user.o
+trace_output-objs := bpf_load.o libbpf.o trace_output_user.o
lathist-objs := bpf_load.o libbpf.o lathist_user.o
# Tell kbuild to always build the programs
@@ -40,6 +42,7 @@
always += tracex4_kern.o
always += tracex5_kern.o
always += tracex6_kern.o
+always += trace_output_kern.o
always += tcbpf1_kern.o
always += lathist_kern.o
@@ -55,6 +58,7 @@
HOSTLOADLIBES_tracex4 += -lelf -lrt
HOSTLOADLIBES_tracex5 += -lelf
HOSTLOADLIBES_tracex6 += -lelf
+HOSTLOADLIBES_trace_output += -lelf -lrt
HOSTLOADLIBES_lathist += -lelf
# point this to your LLVM backend with bpf support
@@ -64,3 +68,6 @@
clang $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) \
-D__KERNEL__ -Wno-unused-value -Wno-pointer-sign \
-O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=obj -o $@
+ clang $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) \
+ -D__KERNEL__ -Wno-unused-value -Wno-pointer-sign \
+ -O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=asm -o $@.s