From: Alexei Starovoitov ast@kernel.org
mainline inclusion from mainline-5.12-rc1 commit f2dd3b39467411c53703125a111f45b3672c1771 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5EUVD CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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Since sleepable programs don't migrate from the cpu the excution stats can be computed for them as well. Reuse the same infrastructure for both sleepable and non-sleepable programs.
run_cnt -> the number of times the program was executed. run_time_ns -> the program execution time in nanoseconds including the off-cpu time when the program was sleeping.
Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Daniel Borkmann daniel@iogearbox.net Acked-by: Andrii Nakryiko andrii@kernel.org Acked-by: KP Singh kpsingh@kernel.org Link: https://lore.kernel.org/bpf/20210210033634.62081-4-alexei.starovoitov@gmail.... (cherry picked from commit f2dd3b39467411c53703125a111f45b3672c1771) Signed-off-by: Wang Yufen wangyufen@huawei.com
Conflicts: include/linux/bpf.h
Signed-off-by: Wang Yufen wangyufen@huawei.com --- arch/x86/net/bpf_jit_comp.c | 31 +++++++++++---------------- include/linux/bpf.h | 4 ++-- kernel/bpf/trampoline.c | 42 ++++++++++++++++++++++++------------- 3 files changed, 42 insertions(+), 35 deletions(-)
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 4c2324295ae2..a96855ffa6e5 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1735,15 +1735,12 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog, u8 *prog = *pprog; int cnt = 0;
- if (p->aux->sleepable) { - if (emit_call(&prog, __bpf_prog_enter_sleepable, prog)) + if (emit_call(&prog, + p->aux->sleepable ? __bpf_prog_enter_sleepable : + __bpf_prog_enter, prog)) return -EINVAL; - } else { - if (emit_call(&prog, __bpf_prog_enter, prog)) - return -EINVAL; - /* remember prog start time returned by __bpf_prog_enter */ - emit_mov_reg(&prog, true, BPF_REG_6, BPF_REG_0); - } + /* remember prog start time returned by __bpf_prog_enter */ + emit_mov_reg(&prog, true, BPF_REG_6, BPF_REG_0);
/* arg1: lea rdi, [rbp - stack_size] */ EMIT4(0x48, 0x8D, 0x7D, -stack_size); @@ -1767,18 +1764,14 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog, if (save_ret) emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -8);
- if (p->aux->sleepable) { - if (emit_call(&prog, __bpf_prog_exit_sleepable, prog)) + /* arg1: mov rdi, progs[i] */ + emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32, (u32) (long) p); + /* arg2: mov rsi, rbx <- start time in nsec */ + emit_mov_reg(&prog, true, BPF_REG_2, BPF_REG_6); + if (emit_call(&prog, + p->aux->sleepable ? __bpf_prog_exit_sleepable : + __bpf_prog_exit, prog)) return -EINVAL; - } else { - /* arg1: mov rdi, progs[i] */ - emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32, - (u32) (long) p); - /* arg2: mov rsi, rbx <- start time in nsec */ - emit_mov_reg(&prog, true, BPF_REG_2, BPF_REG_6); - if (emit_call(&prog, __bpf_prog_exit, prog)) - return -EINVAL; - }
*pprog = prog; return 0; diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 98e0f9dfe898..c2da7c423a0b 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -633,8 +633,8 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *tr, void *image, void *i /* these two functions are called from generated trampoline */ u64 notrace __bpf_prog_enter(void); void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start); -void notrace __bpf_prog_enter_sleepable(void); -void notrace __bpf_prog_exit_sleepable(void); +u64 notrace __bpf_prog_enter_sleepable(void); +void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start); void notrace __bpf_tramp_enter(struct bpf_tramp_image *tr); void notrace __bpf_tramp_exit(struct bpf_tramp_image *tr);
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index e9cc7ac3856f..3c171344f629 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -490,56 +490,70 @@ void bpf_trampoline_put(struct bpf_trampoline *tr) mutex_unlock(&trampoline_mutex); }
+#define NO_START_TIME 0 +static u64 notrace bpf_prog_start_time(void) +{ + u64 start = NO_START_TIME; + + if (static_branch_unlikely(&bpf_stats_enabled_key)) + start = sched_clock(); + return start; +} + /* The logic is similar to BPF_PROG_RUN, but with an explicit * rcu_read_lock() and migrate_disable() which are required * for the trampoline. The macro is split into - * call _bpf_prog_enter + * call __bpf_prog_enter * call prog->bpf_func * call __bpf_prog_exit */ u64 notrace __bpf_prog_enter(void) __acquires(RCU) { - u64 start = 0; - rcu_read_lock(); migrate_disable(); - if (static_branch_unlikely(&bpf_stats_enabled_key)) - start = sched_clock(); - return start; + return bpf_prog_start_time(); }
-void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start) - __releases(RCU) +static void notrace update_prog_stats(struct bpf_prog *prog, + u64 start) { struct bpf_prog_stats *stats;
if (static_branch_unlikely(&bpf_stats_enabled_key) && - /* static_key could be enabled in __bpf_prog_enter - * and disabled in __bpf_prog_exit. + /* static_key could be enabled in __bpf_prog_enter* + * and disabled in __bpf_prog_exit*. * And vice versa. - * Hence check that 'start' is not zero. + * Hence check that 'start' is valid. */ - start) { + start > NO_START_TIME) { stats = this_cpu_ptr(prog->stats); u64_stats_update_begin(&stats->syncp); stats->cnt++; stats->nsecs += sched_clock() - start; u64_stats_update_end(&stats->syncp); } +} + +void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start) + __releases(RCU) +{ + update_prog_stats(prog, start); migrate_enable(); rcu_read_unlock(); }
-void notrace __bpf_prog_enter_sleepable(void) +u64 notrace __bpf_prog_enter_sleepable(void) { rcu_read_lock_trace(); migrate_disable(); might_fault(); + return bpf_prog_start_time(); }
-void notrace __bpf_prog_exit_sleepable(void) +void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start) { + update_prog_stats(prog, start); migrate_enable(); rcu_read_unlock_trace(); }