The patch titled
Subject: tools/testing/selftests/bpf: replace open-coded 16 with TASK_COMM_LEN
has been added to the -mm tree. Its filename is
tools-testing-selftests-bpf-replace-open-coded-16-with-task_comm_len.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/tools-testing-selftests-bpf-replace-open-coded-16-with-task_comm_len.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/tools-testing-selftests-bpf-replace-open-coded-16-with-task_comm_len.patch
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------------------------------------------------------
From: Yafang Shao <laoar.shao@xxxxxxxxx>
Subject: tools/testing/selftests/bpf: replace open-coded 16 with TASK_COMM_LEN
As the sched:sched_switch tracepoint args are derived from the kernel,
we'd better make it same with the kernel. So the macro TASK_COMM_LEN is
converted to type enum, then all the BPF programs can get it through BTF.
The BPF program which wants to use TASK_COMM_LEN should include the header
vmlinux.h. Regarding the test_stacktrace_map and test_tracepoint, as the
type defined in linux/bpf.h are also defined in vmlinux.h, so we don't
need to include linux/bpf.h again.
Link: https://lkml.kernel.org/r/20211120112738.45980-8-laoar.shao@xxxxxxxxx
Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx>
Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Acked-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <arnaldo.melo@xxxxxxxxx>
Cc: Andrii Nakryiko <andrii.nakryiko@xxxxxxxxx>
Cc: Michal Miroslaw <mirq-linux@xxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Petr Mladek <pmladek@xxxxxxxx>
Cc: Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx>
Cc: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/sched.h | 9 +++++++--
tools/testing/selftests/bpf/progs/test_stacktrace_map.c | 6 +++---
tools/testing/selftests/bpf/progs/test_tracepoint.c | 6 +++---
3 files changed, 13 insertions(+), 8 deletions(-)
--- a/include/linux/sched.h~tools-testing-selftests-bpf-replace-open-coded-16-with-task_comm_len
+++ a/include/linux/sched.h
@@ -274,8 +274,13 @@ struct task_group;
#define get_current_state() READ_ONCE(current->__state)
-/* Task command name length: */
-#define TASK_COMM_LEN 16
+/*
+ * Define the task command name length as enum, then it can be visible to
+ * BPF programs.
+ */
+enum {
+ TASK_COMM_LEN = 16,
+};
extern void scheduler_tick(void);
--- a/tools/testing/selftests/bpf/progs/test_stacktrace_map.c~tools-testing-selftests-bpf-replace-open-coded-16-with-task_comm_len
+++ a/tools/testing/selftests/bpf/progs/test_stacktrace_map.c
@@ -1,7 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2018 Facebook
-#include <linux/bpf.h>
+#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
#ifndef PERF_MAX_STACK_DEPTH
@@ -41,11 +41,11 @@ struct {
/* taken from /sys/kernel/debug/tracing/events/sched/sched_switch/format */
struct sched_switch_args {
unsigned long long pad;
- char prev_comm[16];
+ char prev_comm[TASK_COMM_LEN];
int prev_pid;
int prev_prio;
long long prev_state;
- char next_comm[16];
+ char next_comm[TASK_COMM_LEN];
int next_pid;
int next_prio;
};
--- a/tools/testing/selftests/bpf/progs/test_tracepoint.c~tools-testing-selftests-bpf-replace-open-coded-16-with-task_comm_len
+++ a/tools/testing/selftests/bpf/progs/test_tracepoint.c
@@ -1,17 +1,17 @@
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2017 Facebook
-#include <linux/bpf.h>
+#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
/* taken from /sys/kernel/debug/tracing/events/sched/sched_switch/format */
struct sched_switch_args {
unsigned long long pad;
- char prev_comm[16];
+ char prev_comm[TASK_COMM_LEN];
int prev_pid;
int prev_prio;
long long prev_state;
- char next_comm[16];
+ char next_comm[TASK_COMM_LEN];
int next_pid;
int next_prio;
};
_
Patches currently in -mm which might be from laoar.shao@xxxxxxxxx are
fs-exec-replace-strlcpy-with-strscpy_pad-in-__set_task_comm.patch
fs-exec-replace-strncpy-with-strscpy_pad-in-__get_task_comm.patch
drivers-infiniband-replace-open-coded-string-copy-with-get_task_comm.patch
fs-binfmt_elf-replace-open-coded-string-copy-with-get_task_comm.patch
samples-bpf-test_overhead_kprobe_kern-replace-bpf_probe_read_kernel-with-bpf_probe_read_kernel_str-to-get-task-comm.patch
tools-bpf-bpftool-skeleton-replace-bpf_probe_read_kernel-with-bpf_probe_read_kernel_str-to-get-task-comm.patch
tools-testing-selftests-bpf-replace-open-coded-16-with-task_comm_len.patch
