[RFC PATCH bpf-next v2 4/7] bpf: add bpf rstat helpers
From: Yosry Ahmed <hidden>
Date: 2022-05-15 02:36:05
Also in:
bpf, cgroups, lkml
Subsystem:
bpf [core], bpf [general] (safe dynamic programs and tools), bpf [security & lsm] (security audit and enforcement using bpf), bpf [tracing], the rest, tracing · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, KP Singh, Matt Bobrowski, Song Liu, Linus Torvalds, Steven Rostedt, Masami Hiramatsu
Add bpf_cgroup_rstat_updated() and bpf_cgroup_rstat_flush() helpers to enable bpf programs that collect and output cgroup stats to communicate with the rstat frameworkto add a cgroup to the rstat updated tree or trigger an rstat flush before reading stats. Signed-off-by: Yosry Ahmed <redacted> --- include/linux/bpf.h | 2 ++ include/uapi/linux/bpf.h | 18 ++++++++++++++++++ kernel/bpf/helpers.c | 30 ++++++++++++++++++++++++++++++ kernel/trace/bpf_trace.c | 4 ++++ scripts/bpf_doc.py | 2 ++ tools/include/uapi/linux/bpf.h | 18 ++++++++++++++++++ 6 files changed, 74 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 5061ccd8b2dc..ca908a731cb4 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h@@ -2205,6 +2205,8 @@ extern const struct bpf_func_proto bpf_sock_map_update_proto; extern const struct bpf_func_proto bpf_sock_hash_update_proto; extern const struct bpf_func_proto bpf_get_current_cgroup_id_proto; extern const struct bpf_func_proto bpf_get_current_ancestor_cgroup_id_proto; +extern const struct bpf_func_proto bpf_cgroup_rstat_updated_proto; +extern const struct bpf_func_proto bpf_cgroup_rstat_flush_proto; extern const struct bpf_func_proto bpf_msg_redirect_hash_proto; extern const struct bpf_func_proto bpf_msg_redirect_map_proto; extern const struct bpf_func_proto bpf_sk_redirect_hash_proto;
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 968e3cb02580..022522174286 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h@@ -5175,6 +5175,22 @@ union bpf_attr { * Return * Map value associated to *key* on *cpu*, or **NULL** if no entry * was found or *cpu* is invalid. + * + * void bpf_cgroup_rstat_updated(struct cgroup *cgrp) + * Description + * Notify the rstat framework that bpf stats were updated for + * *cgrp* on the current cpu. Directly calls cgroup_rstat_updated + * with the given *cgrp* and the current cpu. + * Return + * 0 + * + * void bpf_cgroup_rstat_flush(struct cgroup *cgrp) + * Description + * Collect all per-cpu stats in *cgrp*'s subtree into global + * counters and propagate them upwards. Directly calls + * cgroup_rstat_flush_irqsafe with the given *cgrp*. + * Return + * 0 */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \
@@ -5373,6 +5389,8 @@ union bpf_attr { FN(ima_file_hash), \ FN(kptr_xchg), \ FN(map_lookup_percpu_elem), \ + FN(cgroup_rstat_updated), \ + FN(cgroup_rstat_flush), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index d5f104a39092..88ed26cf45e2 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c@@ -416,6 +416,36 @@ const struct bpf_func_proto bpf_get_current_ancestor_cgroup_id_proto = { .arg1_type = ARG_ANYTHING, }; +BTF_ID_LIST_SINGLE(bpf_cgroup_btf_ids, struct, cgroup) + +BPF_CALL_1(bpf_cgroup_rstat_updated, struct cgroup *, cgrp) +{ + cgroup_rstat_updated(cgrp, smp_processor_id()); + return 0; +} + +const struct bpf_func_proto bpf_cgroup_rstat_updated_proto = { + .func = bpf_cgroup_rstat_updated, + .gpl_only = false, + .ret_type = RET_VOID, + .arg1_type = ARG_PTR_TO_BTF_ID, + .arg1_btf_id = &bpf_cgroup_btf_ids[0], +}; + +BPF_CALL_1(bpf_cgroup_rstat_flush, struct cgroup *, cgrp) +{ + cgroup_rstat_flush_irqsafe(cgrp); + return 0; +} + +const struct bpf_func_proto bpf_cgroup_rstat_flush_proto = { + .func = bpf_cgroup_rstat_flush, + .gpl_only = false, + .ret_type = RET_VOID, + .arg1_type = ARG_PTR_TO_BTF_ID, + .arg1_btf_id = &bpf_cgroup_btf_ids[0], +}; + #ifdef CONFIG_CGROUP_BPF BPF_CALL_2(bpf_get_local_storage, struct bpf_map *, map, u64, flags)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 7141ca8a1c2d..e5a4f1b6e00d 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c@@ -1255,6 +1255,10 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_current_cgroup_id_proto; case BPF_FUNC_get_current_ancestor_cgroup_id: return &bpf_get_current_ancestor_cgroup_id_proto; + case BPF_FUNC_cgroup_rstat_updated: + return &bpf_cgroup_rstat_updated_proto; + case BPF_FUNC_cgroup_rstat_flush: + return &bpf_cgroup_rstat_flush_proto; #endif case BPF_FUNC_send_signal: return &bpf_send_signal_proto;
diff --git a/scripts/bpf_doc.py b/scripts/bpf_doc.py
index 096625242475..9e2b08557a6f 100755
--- a/scripts/bpf_doc.py
+++ b/scripts/bpf_doc.py@@ -633,6 +633,7 @@ class PrinterHelpers(Printer): 'struct socket', 'struct file', 'struct bpf_timer', + 'struct cgroup', ] known_types = { '...',
@@ -682,6 +683,7 @@ class PrinterHelpers(Printer): 'struct socket', 'struct file', 'struct bpf_timer', + 'struct cgroup', } mapped_types = { 'u8': '__u8',
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 968e3cb02580..022522174286 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h@@ -5175,6 +5175,22 @@ union bpf_attr { * Return * Map value associated to *key* on *cpu*, or **NULL** if no entry * was found or *cpu* is invalid. + * + * void bpf_cgroup_rstat_updated(struct cgroup *cgrp) + * Description + * Notify the rstat framework that bpf stats were updated for + * *cgrp* on the current cpu. Directly calls cgroup_rstat_updated + * with the given *cgrp* and the current cpu. + * Return + * 0 + * + * void bpf_cgroup_rstat_flush(struct cgroup *cgrp) + * Description + * Collect all per-cpu stats in *cgrp*'s subtree into global + * counters and propagate them upwards. Directly calls + * cgroup_rstat_flush_irqsafe with the given *cgrp*. + * Return + * 0 */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \
@@ -5373,6 +5389,8 @@ union bpf_attr { FN(ima_file_hash), \ FN(kptr_xchg), \ FN(map_lookup_percpu_elem), \ + FN(cgroup_rstat_updated), \ + FN(cgroup_rstat_flush), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper
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2.36.0.550.gb090851708-goog