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Diffstat (limited to 'tools/bpf/bpftool/Documentation/bpftool-prog.rst')
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-prog.rst | 30 |
1 files changed, 29 insertions, 1 deletions
diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst index 4b8412fe2c60..2ea5df30ff21 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst @@ -13,7 +13,8 @@ SYNOPSIS **bpftool** [*OPTIONS*] **prog** *COMMAND* *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } | - { **-f** | **--bpffs** } | { **-m** | **--mapcompat** } | { **-n** | **--nomount** } } + { **-f** | **--bpffs** } | { **-m** | **--mapcompat** } | { **-n** | **--nomount** } | + { **-L** | **--use-loader** } } *COMMANDS* := { **show** | **list** | **dump xlated** | **dump jited** | **pin** | **load** @@ -224,6 +225,20 @@ OPTIONS Do not automatically attempt to mount any virtual file system (such as tracefs or BPF virtual file system) when necessary. + -L, --use-loader + Load program as a "loader" program. This is useful to debug + the generation of such programs. When this option is in + use, bpftool attempts to load the programs from the object + file into the kernel, but does not pin them (therefore, the + *PATH* must not be provided). + + When combined with the **-d**\ \|\ **--debug** option, + additional debug messages are generated, and the execution + of the loader program will use the **bpf_trace_printk**\ () + helper to log each step of loading BTF, creating the maps, + and loading the programs (see **bpftool prog tracelog** as + a way to dump those messages). + EXAMPLES ======== **# bpftool prog show** @@ -327,3 +342,16 @@ EXAMPLES 40176203 cycles (83.05%) 42518139 instructions # 1.06 insns per cycle (83.39%) 123 llc_misses # 2.89 LLC misses per million insns (83.15%) + +| +| Output below is for the trace logs. +| Run in separate terminals: +| **# bpftool prog tracelog** +| **# bpftool prog load -L -d file.o** + +:: + + bpftool-620059 [004] d... 2634685.517903: bpf_trace_printk: btf_load size 665 r=5 + bpftool-620059 [004] d... 2634685.517912: bpf_trace_printk: map_create sample_map idx 0 type 2 value_size 4 value_btf_id 0 r=6 + bpftool-620059 [004] d... 2634685.517997: bpf_trace_printk: prog_load sample insn_cnt 13 r=7 + bpftool-620059 [004] d... 2634685.517999: bpf_trace_printk: close(5) = 0 |