From d822a192684912c80950d28a0b7adc96261e957c Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Wed, 25 Mar 2015 12:49:24 -0700 Subject: samples/bpf: Add counting example for kfree_skb() function calls and the write() syscall this example has two probes in one C file that attach to different kprove events and use two different maps. 1st probe is x64 specific equivalent of dropmon. It attaches to kfree_skb, retrevies 'ip' address of kfree_skb() caller and counts number of packet drops at that 'ip' address. User space prints 'location - count' map every second. 2nd probe attaches to kprobe:sys_write and computes a histogram of different write sizes Usage: $ sudo tracex2 location 0xffffffff81695995 count 1 location 0xffffffff816d0da9 count 2 location 0xffffffff81695995 count 2 location 0xffffffff816d0da9 count 2 location 0xffffffff81695995 count 3 location 0xffffffff816d0da9 count 2 557145+0 records in 557145+0 records out 285258240 bytes (285 MB) copied, 1.02379 s, 279 MB/s syscall write() stats byte_size : count distribution 1 -> 1 : 3 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 2 | | 32 -> 63 : 3 | | 64 -> 127 : 1 | | 128 -> 255 : 1 | | 256 -> 511 : 0 | | 512 -> 1023 : 1118968 |************************************* | Ctrl-C at any time. Kernel will auto cleanup maps and programs $ addr2line -ape ./bld_x64/vmlinux 0xffffffff81695995 0xffffffff816d0da9 0xffffffff81695995: ./bld_x64/../net/ipv4/icmp.c:1038 0xffffffff816d0da9: ./bld_x64/../net/unix/af_unix.c:1231 Signed-off-by: Alexei Starovoitov Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Daniel Borkmann Cc: David S. Miller Cc: Jiri Olsa Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Peter Zijlstra Cc: Steven Rostedt Link: http://lkml.kernel.org/r/1427312966-8434-8-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar --- samples/bpf/Makefile | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'samples/bpf/Makefile') diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 51f6f01e5a3a..6dd272143733 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -7,6 +7,7 @@ hostprogs-y += sock_example hostprogs-y += sockex1 hostprogs-y += sockex2 hostprogs-y += tracex1 +hostprogs-y += tracex2 test_verifier-objs := test_verifier.o libbpf.o test_maps-objs := test_maps.o libbpf.o @@ -14,12 +15,14 @@ sock_example-objs := sock_example.o libbpf.o sockex1-objs := bpf_load.o libbpf.o sockex1_user.o sockex2-objs := bpf_load.o libbpf.o sockex2_user.o tracex1-objs := bpf_load.o libbpf.o tracex1_user.o +tracex2-objs := bpf_load.o libbpf.o tracex2_user.o # Tell kbuild to always build the programs always := $(hostprogs-y) always += sockex1_kern.o always += sockex2_kern.o always += tracex1_kern.o +always += tracex2_kern.o HOSTCFLAGS += -I$(objtree)/usr/include @@ -27,6 +30,7 @@ HOSTCFLAGS_bpf_load.o += -I$(objtree)/usr/include -Wno-unused-variable HOSTLOADLIBES_sockex1 += -lelf HOSTLOADLIBES_sockex2 += -lelf HOSTLOADLIBES_tracex1 += -lelf +HOSTLOADLIBES_tracex2 += -lelf # point this to your LLVM backend with bpf support LLC=$(srctree)/tools/bpf/llvm/bld/Debug+Asserts/bin/llc -- cgit v1.2.3