diff options
author | Song Liu <songliubraving@fb.com> | 2020-06-29 23:28:44 -0700 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2020-07-01 08:23:19 -0700 |
commit | fa28dcb82a38f8e3993b0fae9106b1a80b59e4f0 (patch) | |
tree | df5f451d9328757debc8dd7b81a5e34149577f90 /scripts | |
parent | d141b8bc5773cbbaf5b8530f08f94fc10fff9e8c (diff) | |
download | lwn-fa28dcb82a38f8e3993b0fae9106b1a80b59e4f0.tar.gz lwn-fa28dcb82a38f8e3993b0fae9106b1a80b59e4f0.zip |
bpf: Introduce helper bpf_get_task_stack()
Introduce helper bpf_get_task_stack(), which dumps stack trace of given
task. This is different to bpf_get_stack(), which gets stack track of
current task. One potential use case of bpf_get_task_stack() is to call
it from bpf_iter__task and dump all /proc/<pid>/stack to a seq_file.
bpf_get_task_stack() uses stack_trace_save_tsk() instead of
get_perf_callchain() for kernel stack. The benefit of this choice is that
stack_trace_save_tsk() doesn't require changes in arch/. The downside of
using stack_trace_save_tsk() is that stack_trace_save_tsk() dumps the
stack trace to unsigned long array. For 32-bit systems, we need to
translate it to u64 array.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200630062846.664389-3-songliubraving@fb.com
Diffstat (limited to 'scripts')
-rwxr-xr-x | scripts/bpf_helpers_doc.py | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/scripts/bpf_helpers_doc.py b/scripts/bpf_helpers_doc.py index 6bab40ff442e..6843376733df 100755 --- a/scripts/bpf_helpers_doc.py +++ b/scripts/bpf_helpers_doc.py @@ -426,6 +426,7 @@ class PrinterHelpers(Printer): 'struct tcp_timewait_sock', 'struct tcp_request_sock', 'struct udp6_sock', + 'struct task_struct', 'struct __sk_buff', 'struct sk_msg_md', @@ -468,6 +469,7 @@ class PrinterHelpers(Printer): 'struct tcp_timewait_sock', 'struct tcp_request_sock', 'struct udp6_sock', + 'struct task_struct', } mapped_types = { 'u8': '__u8', |