Re: [PATCH v5 11/15] tools/bpf/bpftool: use TASK_COMM_LEN_16 instead of hard-coded 16
From: Andrii Nakryiko <hidden>
Date: 2021-10-21 22:38:24
Also in:
bpf, linux-fsdevel, linux-perf-users, lkml
On Wed, Oct 20, 2021 at 8:46 PM Yafang Shao [off-list ref] wrote:
quoted hunk ↗ jump to hunk
Use TASK_COMM_LEN_16 instead of hard-coded 16 to make it more grepable. It uses bpf_probe_read_kernel() to get task comm, which may return a string without nul terminator. We should use bpf_probe_read_kernel_str() instead. Signed-off-by: Yafang Shao <redacted> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Arnaldo Carvalho de Melo <redacted> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Kees Cook <redacted> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Petr Mladek <pmladek@suse.com> --- tools/bpf/bpftool/Makefile | 1 + tools/bpf/bpftool/main.h | 3 ++- tools/bpf/bpftool/skeleton/pid_iter.bpf.c | 4 ++-- tools/bpf/bpftool/skeleton/pid_iter.h | 4 +++- 4 files changed, 8 insertions(+), 4 deletions(-)diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile index d73232be1e99..33fbde84993c 100644 --- a/tools/bpf/bpftool/Makefile +++ b/tools/bpf/bpftool/Makefile@@ -164,6 +164,7 @@ $(OUTPUT)%.bpf.o: skeleton/%.bpf.c $(OUTPUT)vmlinux.h $(LIBBPF) $(QUIET_CLANG)$(CLANG) \ -I$(if $(OUTPUT),$(OUTPUT),.) \ -I$(srctree)/tools/include/uapi/ \ + -I$(srctree)/tools/include/ \
bpftool shouldn't rely on internal kernel headers for compilation. If you want to have TASK_COMM_LEN_16 constant for grep-ability, just #define it where appropriate
quoted hunk ↗ jump to hunk
-I$(LIBBPF_PATH) \ -I$(srctree)/tools/lib \ -g -O2 -Wall -target bpf -c $< -o $@ && $(LLVM_STRIP) -g $@diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index 90caa42aac4c..5efa27188f68 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h@@ -12,6 +12,7 @@ #include <linux/compiler.h> #include <linux/kernel.h> #include <linux/hashtable.h> +#include <linux/sched/task.h> #include <tools/libc_compat.h>
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