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author | Yafang Shao <laoar.shao@gmail.com> | 2022-01-19 18:08:33 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-01-20 08:52:53 +0200 |
commit | d068144d3b2cae09062ed936a3865c093ff69590 (patch) | |
tree | 42b089f3e3f4a82553c10a095e7192d681e23c7d /samples/bpf | |
parent | 95af469c4f609de011debc08e7a35b45201623a8 (diff) | |
download | linux-stable-d068144d3b2cae09062ed936a3865c093ff69590.tar.gz linux-stable-d068144d3b2cae09062ed936a3865c093ff69590.tar.bz2 linux-stable-d068144d3b2cae09062ed936a3865c093ff69590.zip |
samples/bpf/test_overhead_kprobe_kern: replace bpf_probe_read_kernel with bpf_probe_read_kernel_str to get task comm
bpf_probe_read_kernel_str() will add a nul terminator to the dst, then
we don't care about if the dst size is big enough. This patch also
replaces the hard-coded 16 with TASK_COMM_LEN to make it grepable.
Link: https://lkml.kernel.org/r/20211120112738.45980-6-laoar.shao@gmail.com
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: Michal Miroslaw <mirq-linux@rere.qmqm.pl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'samples/bpf')
-rw-r--r-- | samples/bpf/offwaketime_kern.c | 4 | ||||
-rw-r--r-- | samples/bpf/test_overhead_kprobe_kern.c | 11 | ||||
-rw-r--r-- | samples/bpf/test_overhead_tp_kern.c | 5 |
3 files changed, 11 insertions, 9 deletions
diff --git a/samples/bpf/offwaketime_kern.c b/samples/bpf/offwaketime_kern.c index 4866afd054da..eb4d94742e6b 100644 --- a/samples/bpf/offwaketime_kern.c +++ b/samples/bpf/offwaketime_kern.c @@ -113,11 +113,11 @@ static inline int update_counts(void *ctx, u32 pid, u64 delta) /* 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; }; diff --git a/samples/bpf/test_overhead_kprobe_kern.c b/samples/bpf/test_overhead_kprobe_kern.c index f6d593e47037..8fdd2c9c56b2 100644 --- a/samples/bpf/test_overhead_kprobe_kern.c +++ b/samples/bpf/test_overhead_kprobe_kern.c @@ -6,6 +6,7 @@ */ #include <linux/version.h> #include <linux/ptrace.h> +#include <linux/sched.h> #include <uapi/linux/bpf.h> #include <bpf/bpf_helpers.h> #include <bpf/bpf_tracing.h> @@ -22,17 +23,17 @@ int prog(struct pt_regs *ctx) { struct signal_struct *signal; struct task_struct *tsk; - char oldcomm[16] = {}; - char newcomm[16] = {}; + char oldcomm[TASK_COMM_LEN] = {}; + char newcomm[TASK_COMM_LEN] = {}; u16 oom_score_adj; u32 pid; tsk = (void *)PT_REGS_PARM1(ctx); pid = _(tsk->pid); - bpf_probe_read_kernel(oldcomm, sizeof(oldcomm), &tsk->comm); - bpf_probe_read_kernel(newcomm, sizeof(newcomm), - (void *)PT_REGS_PARM2(ctx)); + bpf_probe_read_kernel_str(oldcomm, sizeof(oldcomm), &tsk->comm); + bpf_probe_read_kernel_str(newcomm, sizeof(newcomm), + (void *)PT_REGS_PARM2(ctx)); signal = _(tsk->signal); oom_score_adj = _(signal->oom_score_adj); return 0; diff --git a/samples/bpf/test_overhead_tp_kern.c b/samples/bpf/test_overhead_tp_kern.c index eaa32693f8fc..80edadacb692 100644 --- a/samples/bpf/test_overhead_tp_kern.c +++ b/samples/bpf/test_overhead_tp_kern.c @@ -4,6 +4,7 @@ * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. */ +#include <linux/sched.h> #include <uapi/linux/bpf.h> #include <bpf/bpf_helpers.h> @@ -11,8 +12,8 @@ struct task_rename { __u64 pad; __u32 pid; - char oldcomm[16]; - char newcomm[16]; + char oldcomm[TASK_COMM_LEN]; + char newcomm[TASK_COMM_LEN]; __u16 oom_score_adj; }; SEC("tracepoint/task/task_rename") |