linux/samples/bpf/Makefile

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# kbuild trick to avoid linker error. Can be omitted if a module is built.
obj- := dummy.o
# List of programs to build
hostprogs-y := test_verifier test_maps
hostprogs-y += sock_example
bpf: add sample usages for persistent maps/progs This patch adds a couple of stand-alone examples on how BPF_OBJ_PIN and BPF_OBJ_GET commands can be used. Example with maps: # ./fds_example -F /sys/fs/bpf/m -P -m -k 1 -v 42 bpf: map fd:3 (Success) bpf: pin ret:(0,Success) bpf: fd:3 u->(1:42) ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):42 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 -v 24 bpf: get fd:3 (Success) bpf: fd:3 u->(1:24) ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):24 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -P -m bpf: map fd:3 (Success) bpf: pin ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):0 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -G -m bpf: get fd:3 (Success) Example with progs: # ./fds_example -F /sys/fs/bpf/p -P -p bpf: prog fd:3 (Success) bpf: pin ret:(0,Success) bpf sock:4 <- fd:3 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p -G -p bpf: get fd:3 (Success) bpf: sock:4 <- fd:3 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p2 -P -p -o ./sockex1_kern.o bpf: prog fd:5 (Success) bpf: pin ret:(0,Success) bpf: sock:3 <- fd:5 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p2 -G -p bpf: get fd:3 (Success) bpf: sock:4 <- fd:3 attached ret:(0,Success) Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-29 14:58:10 +01:00
hostprogs-y += fds_example
hostprogs-y += sockex1
hostprogs-y += sockex2
hostprogs-y += sockex3
samples/bpf: Add simple non-portable kprobe filter example tracex1_kern.c - C program compiled into BPF. It attaches to kprobe:netif_receive_skb() When skb->dev->name == "lo", it prints sample debug message into trace_pipe via bpf_trace_printk() helper function. tracex1_user.c - corresponding user space component that: - loads BPF program via bpf() syscall - opens kprobes:netif_receive_skb event via perf_event_open() syscall - attaches the program to event via ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); - prints from trace_pipe Note, this BPF program is non-portable. It must be recompiled with current kernel headers. kprobe is not a stable ABI and BPF+kprobe scripts may no longer be meaningful when kernel internals change. No matter in what way the kernel changes, neither the kprobe, nor the BPF program can ever crash or corrupt the kernel, assuming the kprobes, perf and BPF subsystem has no bugs. The verifier will detect that the program is using bpf_trace_printk() and the kernel will print 'this is a DEBUG kernel' warning banner, which means that bpf_trace_printk() should be used for debugging of the BPF program only. Usage: $ sudo tracex1 ping-19826 [000] d.s2 63103.382648: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63103.382684: : skb ffff880466b1d300 len 84 ping-19826 [000] d.s2 63104.382533: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63104.382594: : skb ffff880466b1d300 len 84 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-7-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:23 +01:00
hostprogs-y += tracex1
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 <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-8-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:24 +01:00
hostprogs-y += tracex2
samples/bpf: Add IO latency analysis (iosnoop/heatmap) tool BPF C program attaches to blk_mq_start_request()/blk_update_request() kprobe events to calculate IO latency. For every completed block IO event it computes the time delta in nsec and records in a histogram map: map[log10(delta)*10]++ User space reads this histogram map every 2 seconds and prints it as a 'heatmap' using gray shades of text terminal. Black spaces have many events and white spaces have very few events. Left most space is the smallest latency, right most space is the largest latency in the range. Usage: $ sudo ./tracex3 and do 'sudo dd if=/dev/sda of=/dev/null' in other terminal. Observe IO latencies and how different activity (like 'make kernel') affects it. Similar experiments can be done for network transmit latencies, syscalls, etc. '-t' flag prints the heatmap using normal ascii characters: $ sudo ./tracex3 -t heatmap of IO latency # - many events with this latency - few events |1us |10us |100us |1ms |10ms |100ms |1s |10s *ooo. *O.#. # 221 . *# . # 125 .. .o#*.. # 55 . . . . .#O # 37 .# # 175 .#*. # 37 # # 199 . . *#*. # 55 *#..* # 42 # # 266 ...***Oo#*OO**o#* . # 629 # # 271 . .#o* o.*o* # 221 . . o* *#O.. # 50 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-9-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:25 +01:00
hostprogs-y += tracex3
samples/bpf: Add kmem_alloc()/free() tracker tool One BPF program attaches to kmem_cache_alloc_node() and remembers all allocated objects in the map. Another program attaches to kmem_cache_free() and deletes corresponding object from the map. User space walks the map every second and prints any objects which are older than 1 second. Usage: $ sudo tracex4 Then start few long living processes. The 'tracex4' will print something like this: obj 0xffff880465928000 is 13sec old was allocated at ip ffffffff8105dc32 obj 0xffff88043181c280 is 13sec old was allocated at ip ffffffff8105dc32 obj 0xffff880465848000 is 8sec old was allocated at ip ffffffff8105dc32 obj 0xffff8804338bc280 is 15sec old was allocated at ip ffffffff8105dc32 $ addr2line -fispe vmlinux ffffffff8105dc32 do_fork at fork.c:1665 As soon as processes exit the memory is reclaimed and 'tracex4' prints nothing. Similar experiment can be done with the __kmalloc()/kfree() pair. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-10-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:26 +01:00
hostprogs-y += tracex4
hostprogs-y += tracex5
hostprogs-y += tracex6
hostprogs-y += trace_output
bpf: BPF based latency tracing BPF offers another way to generate latency histograms. We attach kprobes at trace_preempt_off and trace_preempt_on and calculate the time it takes to from seeing the off/on transition. The first array is used to store the start time stamp. The key is the CPU id. The second array stores the log2(time diff). We need to use static allocation here (array and not hash tables). The kprobes hooking into trace_preempt_on|off should not calling any dynamic memory allocation or free path. We need to avoid recursivly getting called. Besides that, it reduces jitter in the measurement. CPU 0 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 166723 |*************************************** | 4096 -> 8191 : 19870 |*** | 8192 -> 16383 : 6324 | | 16384 -> 32767 : 1098 | | 32768 -> 65535 : 190 | | 65536 -> 131071 : 179 | | 131072 -> 262143 : 18 | | 262144 -> 524287 : 4 | | 524288 -> 1048575 : 1363 | | CPU 1 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 114042 |*************************************** | 4096 -> 8191 : 9587 |** | 8192 -> 16383 : 4140 | | 16384 -> 32767 : 673 | | 32768 -> 65535 : 179 | | 65536 -> 131071 : 29 | | 131072 -> 262143 : 4 | | 262144 -> 524287 : 1 | | 524288 -> 1048575 : 364 | | CPU 2 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 40147 |*************************************** | 4096 -> 8191 : 2300 |* | 8192 -> 16383 : 828 | | 16384 -> 32767 : 178 | | 32768 -> 65535 : 59 | | 65536 -> 131071 : 2 | | 131072 -> 262143 : 0 | | 262144 -> 524287 : 1 | | 524288 -> 1048575 : 174 | | CPU 3 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 29626 |*************************************** | 4096 -> 8191 : 2704 |** | 8192 -> 16383 : 1090 | | 16384 -> 32767 : 160 | | 32768 -> 65535 : 72 | | 65536 -> 131071 : 32 | | 131072 -> 262143 : 26 | | 262144 -> 524287 : 12 | | 524288 -> 1048575 : 298 | | All this is based on the trace3 examples written by Alexei Starovoitov <ast@plumgrid.com>. Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-19 16:00:44 +02:00
hostprogs-y += lathist
test_verifier-objs := test_verifier.o libbpf.o
test_maps-objs := test_maps.o libbpf.o
sock_example-objs := sock_example.o libbpf.o
bpf: add sample usages for persistent maps/progs This patch adds a couple of stand-alone examples on how BPF_OBJ_PIN and BPF_OBJ_GET commands can be used. Example with maps: # ./fds_example -F /sys/fs/bpf/m -P -m -k 1 -v 42 bpf: map fd:3 (Success) bpf: pin ret:(0,Success) bpf: fd:3 u->(1:42) ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):42 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 -v 24 bpf: get fd:3 (Success) bpf: fd:3 u->(1:24) ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):24 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -P -m bpf: map fd:3 (Success) bpf: pin ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):0 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -G -m bpf: get fd:3 (Success) Example with progs: # ./fds_example -F /sys/fs/bpf/p -P -p bpf: prog fd:3 (Success) bpf: pin ret:(0,Success) bpf sock:4 <- fd:3 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p -G -p bpf: get fd:3 (Success) bpf: sock:4 <- fd:3 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p2 -P -p -o ./sockex1_kern.o bpf: prog fd:5 (Success) bpf: pin ret:(0,Success) bpf: sock:3 <- fd:5 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p2 -G -p bpf: get fd:3 (Success) bpf: sock:4 <- fd:3 attached ret:(0,Success) Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-29 14:58:10 +01:00
fds_example-objs := bpf_load.o libbpf.o fds_example.o
sockex1-objs := bpf_load.o libbpf.o sockex1_user.o
sockex2-objs := bpf_load.o libbpf.o sockex2_user.o
sockex3-objs := bpf_load.o libbpf.o sockex3_user.o
samples/bpf: Add simple non-portable kprobe filter example tracex1_kern.c - C program compiled into BPF. It attaches to kprobe:netif_receive_skb() When skb->dev->name == "lo", it prints sample debug message into trace_pipe via bpf_trace_printk() helper function. tracex1_user.c - corresponding user space component that: - loads BPF program via bpf() syscall - opens kprobes:netif_receive_skb event via perf_event_open() syscall - attaches the program to event via ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); - prints from trace_pipe Note, this BPF program is non-portable. It must be recompiled with current kernel headers. kprobe is not a stable ABI and BPF+kprobe scripts may no longer be meaningful when kernel internals change. No matter in what way the kernel changes, neither the kprobe, nor the BPF program can ever crash or corrupt the kernel, assuming the kprobes, perf and BPF subsystem has no bugs. The verifier will detect that the program is using bpf_trace_printk() and the kernel will print 'this is a DEBUG kernel' warning banner, which means that bpf_trace_printk() should be used for debugging of the BPF program only. Usage: $ sudo tracex1 ping-19826 [000] d.s2 63103.382648: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63103.382684: : skb ffff880466b1d300 len 84 ping-19826 [000] d.s2 63104.382533: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63104.382594: : skb ffff880466b1d300 len 84 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-7-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:23 +01:00
tracex1-objs := bpf_load.o libbpf.o tracex1_user.o
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 <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-8-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:24 +01:00
tracex2-objs := bpf_load.o libbpf.o tracex2_user.o
samples/bpf: Add IO latency analysis (iosnoop/heatmap) tool BPF C program attaches to blk_mq_start_request()/blk_update_request() kprobe events to calculate IO latency. For every completed block IO event it computes the time delta in nsec and records in a histogram map: map[log10(delta)*10]++ User space reads this histogram map every 2 seconds and prints it as a 'heatmap' using gray shades of text terminal. Black spaces have many events and white spaces have very few events. Left most space is the smallest latency, right most space is the largest latency in the range. Usage: $ sudo ./tracex3 and do 'sudo dd if=/dev/sda of=/dev/null' in other terminal. Observe IO latencies and how different activity (like 'make kernel') affects it. Similar experiments can be done for network transmit latencies, syscalls, etc. '-t' flag prints the heatmap using normal ascii characters: $ sudo ./tracex3 -t heatmap of IO latency # - many events with this latency - few events |1us |10us |100us |1ms |10ms |100ms |1s |10s *ooo. *O.#. # 221 . *# . # 125 .. .o#*.. # 55 . . . . .#O # 37 .# # 175 .#*. # 37 # # 199 . . *#*. # 55 *#..* # 42 # # 266 ...***Oo#*OO**o#* . # 629 # # 271 . .#o* o.*o* # 221 . . o* *#O.. # 50 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-9-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:25 +01:00
tracex3-objs := bpf_load.o libbpf.o tracex3_user.o
samples/bpf: Add kmem_alloc()/free() tracker tool One BPF program attaches to kmem_cache_alloc_node() and remembers all allocated objects in the map. Another program attaches to kmem_cache_free() and deletes corresponding object from the map. User space walks the map every second and prints any objects which are older than 1 second. Usage: $ sudo tracex4 Then start few long living processes. The 'tracex4' will print something like this: obj 0xffff880465928000 is 13sec old was allocated at ip ffffffff8105dc32 obj 0xffff88043181c280 is 13sec old was allocated at ip ffffffff8105dc32 obj 0xffff880465848000 is 8sec old was allocated at ip ffffffff8105dc32 obj 0xffff8804338bc280 is 15sec old was allocated at ip ffffffff8105dc32 $ addr2line -fispe vmlinux ffffffff8105dc32 do_fork at fork.c:1665 As soon as processes exit the memory is reclaimed and 'tracex4' prints nothing. Similar experiment can be done with the __kmalloc()/kfree() pair. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-10-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:26 +01:00
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
bpf: BPF based latency tracing BPF offers another way to generate latency histograms. We attach kprobes at trace_preempt_off and trace_preempt_on and calculate the time it takes to from seeing the off/on transition. The first array is used to store the start time stamp. The key is the CPU id. The second array stores the log2(time diff). We need to use static allocation here (array and not hash tables). The kprobes hooking into trace_preempt_on|off should not calling any dynamic memory allocation or free path. We need to avoid recursivly getting called. Besides that, it reduces jitter in the measurement. CPU 0 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 166723 |*************************************** | 4096 -> 8191 : 19870 |*** | 8192 -> 16383 : 6324 | | 16384 -> 32767 : 1098 | | 32768 -> 65535 : 190 | | 65536 -> 131071 : 179 | | 131072 -> 262143 : 18 | | 262144 -> 524287 : 4 | | 524288 -> 1048575 : 1363 | | CPU 1 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 114042 |*************************************** | 4096 -> 8191 : 9587 |** | 8192 -> 16383 : 4140 | | 16384 -> 32767 : 673 | | 32768 -> 65535 : 179 | | 65536 -> 131071 : 29 | | 131072 -> 262143 : 4 | | 262144 -> 524287 : 1 | | 524288 -> 1048575 : 364 | | CPU 2 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 40147 |*************************************** | 4096 -> 8191 : 2300 |* | 8192 -> 16383 : 828 | | 16384 -> 32767 : 178 | | 32768 -> 65535 : 59 | | 65536 -> 131071 : 2 | | 131072 -> 262143 : 0 | | 262144 -> 524287 : 1 | | 524288 -> 1048575 : 174 | | CPU 3 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 29626 |*************************************** | 4096 -> 8191 : 2704 |** | 8192 -> 16383 : 1090 | | 16384 -> 32767 : 160 | | 32768 -> 65535 : 72 | | 65536 -> 131071 : 32 | | 131072 -> 262143 : 26 | | 262144 -> 524287 : 12 | | 524288 -> 1048575 : 298 | | All this is based on the trace3 examples written by Alexei Starovoitov <ast@plumgrid.com>. Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-19 16:00:44 +02:00
lathist-objs := bpf_load.o libbpf.o lathist_user.o
# Tell kbuild to always build the programs
always := $(hostprogs-y)
always += sockex1_kern.o
always += sockex2_kern.o
always += sockex3_kern.o
samples/bpf: Add simple non-portable kprobe filter example tracex1_kern.c - C program compiled into BPF. It attaches to kprobe:netif_receive_skb() When skb->dev->name == "lo", it prints sample debug message into trace_pipe via bpf_trace_printk() helper function. tracex1_user.c - corresponding user space component that: - loads BPF program via bpf() syscall - opens kprobes:netif_receive_skb event via perf_event_open() syscall - attaches the program to event via ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); - prints from trace_pipe Note, this BPF program is non-portable. It must be recompiled with current kernel headers. kprobe is not a stable ABI and BPF+kprobe scripts may no longer be meaningful when kernel internals change. No matter in what way the kernel changes, neither the kprobe, nor the BPF program can ever crash or corrupt the kernel, assuming the kprobes, perf and BPF subsystem has no bugs. The verifier will detect that the program is using bpf_trace_printk() and the kernel will print 'this is a DEBUG kernel' warning banner, which means that bpf_trace_printk() should be used for debugging of the BPF program only. Usage: $ sudo tracex1 ping-19826 [000] d.s2 63103.382648: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63103.382684: : skb ffff880466b1d300 len 84 ping-19826 [000] d.s2 63104.382533: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63104.382594: : skb ffff880466b1d300 len 84 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-7-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:23 +01:00
always += tracex1_kern.o
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 <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-8-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:24 +01:00
always += tracex2_kern.o
samples/bpf: Add IO latency analysis (iosnoop/heatmap) tool BPF C program attaches to blk_mq_start_request()/blk_update_request() kprobe events to calculate IO latency. For every completed block IO event it computes the time delta in nsec and records in a histogram map: map[log10(delta)*10]++ User space reads this histogram map every 2 seconds and prints it as a 'heatmap' using gray shades of text terminal. Black spaces have many events and white spaces have very few events. Left most space is the smallest latency, right most space is the largest latency in the range. Usage: $ sudo ./tracex3 and do 'sudo dd if=/dev/sda of=/dev/null' in other terminal. Observe IO latencies and how different activity (like 'make kernel') affects it. Similar experiments can be done for network transmit latencies, syscalls, etc. '-t' flag prints the heatmap using normal ascii characters: $ sudo ./tracex3 -t heatmap of IO latency # - many events with this latency - few events |1us |10us |100us |1ms |10ms |100ms |1s |10s *ooo. *O.#. # 221 . *# . # 125 .. .o#*.. # 55 . . . . .#O # 37 .# # 175 .#*. # 37 # # 199 . . *#*. # 55 *#..* # 42 # # 266 ...***Oo#*OO**o#* . # 629 # # 271 . .#o* o.*o* # 221 . . o* *#O.. # 50 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-9-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:25 +01:00
always += tracex3_kern.o
samples/bpf: Add kmem_alloc()/free() tracker tool One BPF program attaches to kmem_cache_alloc_node() and remembers all allocated objects in the map. Another program attaches to kmem_cache_free() and deletes corresponding object from the map. User space walks the map every second and prints any objects which are older than 1 second. Usage: $ sudo tracex4 Then start few long living processes. The 'tracex4' will print something like this: obj 0xffff880465928000 is 13sec old was allocated at ip ffffffff8105dc32 obj 0xffff88043181c280 is 13sec old was allocated at ip ffffffff8105dc32 obj 0xffff880465848000 is 8sec old was allocated at ip ffffffff8105dc32 obj 0xffff8804338bc280 is 15sec old was allocated at ip ffffffff8105dc32 $ addr2line -fispe vmlinux ffffffff8105dc32 do_fork at fork.c:1665 As soon as processes exit the memory is reclaimed and 'tracex4' prints nothing. Similar experiment can be done with the __kmalloc()/kfree() pair. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-10-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:26 +01:00
always += tracex4_kern.o
always += tracex5_kern.o
always += tracex6_kern.o
always += trace_output_kern.o
always += tcbpf1_kern.o
bpf: BPF based latency tracing BPF offers another way to generate latency histograms. We attach kprobes at trace_preempt_off and trace_preempt_on and calculate the time it takes to from seeing the off/on transition. The first array is used to store the start time stamp. The key is the CPU id. The second array stores the log2(time diff). We need to use static allocation here (array and not hash tables). The kprobes hooking into trace_preempt_on|off should not calling any dynamic memory allocation or free path. We need to avoid recursivly getting called. Besides that, it reduces jitter in the measurement. CPU 0 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 166723 |*************************************** | 4096 -> 8191 : 19870 |*** | 8192 -> 16383 : 6324 | | 16384 -> 32767 : 1098 | | 32768 -> 65535 : 190 | | 65536 -> 131071 : 179 | | 131072 -> 262143 : 18 | | 262144 -> 524287 : 4 | | 524288 -> 1048575 : 1363 | | CPU 1 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 114042 |*************************************** | 4096 -> 8191 : 9587 |** | 8192 -> 16383 : 4140 | | 16384 -> 32767 : 673 | | 32768 -> 65535 : 179 | | 65536 -> 131071 : 29 | | 131072 -> 262143 : 4 | | 262144 -> 524287 : 1 | | 524288 -> 1048575 : 364 | | CPU 2 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 40147 |*************************************** | 4096 -> 8191 : 2300 |* | 8192 -> 16383 : 828 | | 16384 -> 32767 : 178 | | 32768 -> 65535 : 59 | | 65536 -> 131071 : 2 | | 131072 -> 262143 : 0 | | 262144 -> 524287 : 1 | | 524288 -> 1048575 : 174 | | CPU 3 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 29626 |*************************************** | 4096 -> 8191 : 2704 |** | 8192 -> 16383 : 1090 | | 16384 -> 32767 : 160 | | 32768 -> 65535 : 72 | | 65536 -> 131071 : 32 | | 131072 -> 262143 : 26 | | 262144 -> 524287 : 12 | | 524288 -> 1048575 : 298 | | All this is based on the trace3 examples written by Alexei Starovoitov <ast@plumgrid.com>. Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-19 16:00:44 +02:00
always += lathist_kern.o
HOSTCFLAGS += -I$(objtree)/usr/include
HOSTCFLAGS_bpf_load.o += -I$(objtree)/usr/include -Wno-unused-variable
bpf: add sample usages for persistent maps/progs This patch adds a couple of stand-alone examples on how BPF_OBJ_PIN and BPF_OBJ_GET commands can be used. Example with maps: # ./fds_example -F /sys/fs/bpf/m -P -m -k 1 -v 42 bpf: map fd:3 (Success) bpf: pin ret:(0,Success) bpf: fd:3 u->(1:42) ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):42 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 -v 24 bpf: get fd:3 (Success) bpf: fd:3 u->(1:24) ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):24 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -P -m bpf: map fd:3 (Success) bpf: pin ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):0 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -G -m bpf: get fd:3 (Success) Example with progs: # ./fds_example -F /sys/fs/bpf/p -P -p bpf: prog fd:3 (Success) bpf: pin ret:(0,Success) bpf sock:4 <- fd:3 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p -G -p bpf: get fd:3 (Success) bpf: sock:4 <- fd:3 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p2 -P -p -o ./sockex1_kern.o bpf: prog fd:5 (Success) bpf: pin ret:(0,Success) bpf: sock:3 <- fd:5 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p2 -G -p bpf: get fd:3 (Success) bpf: sock:4 <- fd:3 attached ret:(0,Success) Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-29 14:58:10 +01:00
HOSTLOADLIBES_fds_example += -lelf
HOSTLOADLIBES_sockex1 += -lelf
HOSTLOADLIBES_sockex2 += -lelf
HOSTLOADLIBES_sockex3 += -lelf
samples/bpf: Add simple non-portable kprobe filter example tracex1_kern.c - C program compiled into BPF. It attaches to kprobe:netif_receive_skb() When skb->dev->name == "lo", it prints sample debug message into trace_pipe via bpf_trace_printk() helper function. tracex1_user.c - corresponding user space component that: - loads BPF program via bpf() syscall - opens kprobes:netif_receive_skb event via perf_event_open() syscall - attaches the program to event via ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); - prints from trace_pipe Note, this BPF program is non-portable. It must be recompiled with current kernel headers. kprobe is not a stable ABI and BPF+kprobe scripts may no longer be meaningful when kernel internals change. No matter in what way the kernel changes, neither the kprobe, nor the BPF program can ever crash or corrupt the kernel, assuming the kprobes, perf and BPF subsystem has no bugs. The verifier will detect that the program is using bpf_trace_printk() and the kernel will print 'this is a DEBUG kernel' warning banner, which means that bpf_trace_printk() should be used for debugging of the BPF program only. Usage: $ sudo tracex1 ping-19826 [000] d.s2 63103.382648: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63103.382684: : skb ffff880466b1d300 len 84 ping-19826 [000] d.s2 63104.382533: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63104.382594: : skb ffff880466b1d300 len 84 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-7-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:23 +01:00
HOSTLOADLIBES_tracex1 += -lelf
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 <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-8-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:24 +01:00
HOSTLOADLIBES_tracex2 += -lelf
samples/bpf: Add IO latency analysis (iosnoop/heatmap) tool BPF C program attaches to blk_mq_start_request()/blk_update_request() kprobe events to calculate IO latency. For every completed block IO event it computes the time delta in nsec and records in a histogram map: map[log10(delta)*10]++ User space reads this histogram map every 2 seconds and prints it as a 'heatmap' using gray shades of text terminal. Black spaces have many events and white spaces have very few events. Left most space is the smallest latency, right most space is the largest latency in the range. Usage: $ sudo ./tracex3 and do 'sudo dd if=/dev/sda of=/dev/null' in other terminal. Observe IO latencies and how different activity (like 'make kernel') affects it. Similar experiments can be done for network transmit latencies, syscalls, etc. '-t' flag prints the heatmap using normal ascii characters: $ sudo ./tracex3 -t heatmap of IO latency # - many events with this latency - few events |1us |10us |100us |1ms |10ms |100ms |1s |10s *ooo. *O.#. # 221 . *# . # 125 .. .o#*.. # 55 . . . . .#O # 37 .# # 175 .#*. # 37 # # 199 . . *#*. # 55 *#..* # 42 # # 266 ...***Oo#*OO**o#* . # 629 # # 271 . .#o* o.*o* # 221 . . o* *#O.. # 50 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-9-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:25 +01:00
HOSTLOADLIBES_tracex3 += -lelf
samples/bpf: Add kmem_alloc()/free() tracker tool One BPF program attaches to kmem_cache_alloc_node() and remembers all allocated objects in the map. Another program attaches to kmem_cache_free() and deletes corresponding object from the map. User space walks the map every second and prints any objects which are older than 1 second. Usage: $ sudo tracex4 Then start few long living processes. The 'tracex4' will print something like this: obj 0xffff880465928000 is 13sec old was allocated at ip ffffffff8105dc32 obj 0xffff88043181c280 is 13sec old was allocated at ip ffffffff8105dc32 obj 0xffff880465848000 is 8sec old was allocated at ip ffffffff8105dc32 obj 0xffff8804338bc280 is 15sec old was allocated at ip ffffffff8105dc32 $ addr2line -fispe vmlinux ffffffff8105dc32 do_fork at fork.c:1665 As soon as processes exit the memory is reclaimed and 'tracex4' prints nothing. Similar experiment can be done with the __kmalloc()/kfree() pair. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-10-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 20:49:26 +01:00
HOSTLOADLIBES_tracex4 += -lelf -lrt
HOSTLOADLIBES_tracex5 += -lelf
HOSTLOADLIBES_tracex6 += -lelf
HOSTLOADLIBES_trace_output += -lelf -lrt
bpf: BPF based latency tracing BPF offers another way to generate latency histograms. We attach kprobes at trace_preempt_off and trace_preempt_on and calculate the time it takes to from seeing the off/on transition. The first array is used to store the start time stamp. The key is the CPU id. The second array stores the log2(time diff). We need to use static allocation here (array and not hash tables). The kprobes hooking into trace_preempt_on|off should not calling any dynamic memory allocation or free path. We need to avoid recursivly getting called. Besides that, it reduces jitter in the measurement. CPU 0 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 166723 |*************************************** | 4096 -> 8191 : 19870 |*** | 8192 -> 16383 : 6324 | | 16384 -> 32767 : 1098 | | 32768 -> 65535 : 190 | | 65536 -> 131071 : 179 | | 131072 -> 262143 : 18 | | 262144 -> 524287 : 4 | | 524288 -> 1048575 : 1363 | | CPU 1 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 114042 |*************************************** | 4096 -> 8191 : 9587 |** | 8192 -> 16383 : 4140 | | 16384 -> 32767 : 673 | | 32768 -> 65535 : 179 | | 65536 -> 131071 : 29 | | 131072 -> 262143 : 4 | | 262144 -> 524287 : 1 | | 524288 -> 1048575 : 364 | | CPU 2 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 40147 |*************************************** | 4096 -> 8191 : 2300 |* | 8192 -> 16383 : 828 | | 16384 -> 32767 : 178 | | 32768 -> 65535 : 59 | | 65536 -> 131071 : 2 | | 131072 -> 262143 : 0 | | 262144 -> 524287 : 1 | | 524288 -> 1048575 : 174 | | CPU 3 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 29626 |*************************************** | 4096 -> 8191 : 2704 |** | 8192 -> 16383 : 1090 | | 16384 -> 32767 : 160 | | 32768 -> 65535 : 72 | | 65536 -> 131071 : 32 | | 131072 -> 262143 : 26 | | 262144 -> 524287 : 12 | | 524288 -> 1048575 : 298 | | All this is based on the trace3 examples written by Alexei Starovoitov <ast@plumgrid.com>. Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-19 16:00:44 +02:00
HOSTLOADLIBES_lathist += -lelf
# point this to your LLVM backend with bpf support
LLC=$(srctree)/tools/bpf/llvm/bld/Debug+Asserts/bin/llc
# asm/sysreg.h inline assmbly used by it is incompatible with llvm.
# But, ehere is not easy way to fix it, so just exclude it since it is
# useless for BPF samples.
$(obj)/%.o: $(src)/%.c
clang $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) \
-D__KERNEL__ -D__ASM_SYSREG_H -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__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
-O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=asm -o $@.s