From d53dee3fe0138610fcce5721bae9414377c41ec3 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 19 Jun 2020 16:17:02 -0700 Subject: tools/bpftool: Show info for processes holding BPF map/prog/link/btf FDs Add bpf_iter-based way to find all the processes that hold open FDs against BPF object (map, prog, link, btf). bpftool always attempts to discover this, but will silently give up if kernel doesn't yet support bpf_iter BPF programs. Process name and PID are emitted for each process (task group). Sample output for each of 4 BPF objects: $ sudo ./bpftool prog show 2694: cgroup_device tag 8c42dee26e8cd4c2 gpl loaded_at 2020-06-16T15:34:32-0700 uid 0 xlated 648B jited 409B memlock 4096B pids systemd(1) 2907: cgroup_skb name egress tag 9ad187367cf2b9e8 gpl loaded_at 2020-06-16T18:06:54-0700 uid 0 xlated 48B jited 59B memlock 4096B map_ids 2436 btf_id 1202 pids test_progs(2238417), test_progs(2238445) $ sudo ./bpftool map show 2436: array name test_cgr.bss flags 0x400 key 4B value 8B max_entries 1 memlock 8192B btf_id 1202 pids test_progs(2238417), test_progs(2238445) 2445: array name pid_iter.rodata flags 0x480 key 4B value 4B max_entries 1 memlock 8192B btf_id 1214 frozen pids bpftool(2239612) $ sudo ./bpftool link show 61: cgroup prog 2908 cgroup_id 375301 attach_type egress pids test_progs(2238417), test_progs(2238445) 62: cgroup prog 2908 cgroup_id 375344 attach_type egress pids test_progs(2238417), test_progs(2238445) $ sudo ./bpftool btf show 1202: size 1527B prog_ids 2908,2907 map_ids 2436 pids test_progs(2238417), test_progs(2238445) 1242: size 34684B pids bpftool(2258892) Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20200619231703.738941-9-andriin@fb.com --- tools/bpf/bpftool/Makefile | 2 ++ 1 file changed, 2 insertions(+) (limited to 'tools/bpf/bpftool/Makefile') diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile index bdb6e38c6c5c..06f436e8191a 100644 --- a/tools/bpf/bpftool/Makefile +++ b/tools/bpf/bpftool/Makefile @@ -150,6 +150,8 @@ $(OUTPUT)%.skel.h: $(OUTPUT)%.bpf.o $(BPFTOOL_BOOTSTRAP) $(OUTPUT)prog.o: $(OUTPUT)profiler.skel.h +$(OUTPUT)pids.o: $(OUTPUT)pid_iter.skel.h + endif endif -- cgit v1.2.3