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authorDavid S. Miller <davem@davemloft.net>2017-11-11 18:24:55 +0900
committerDavid S. Miller <davem@davemloft.net>2017-11-11 18:24:55 +0900
commitf3edacbd697f94a743fff1a3d26910ab99948ba7 (patch)
treec185057f2e3ae783ad3ccd5b5b96af200d2eb618 /kernel/trace/trace_kprobe.c
parentbee955cd3ab4f1a1eb8fc16e7ed69364143df8d7 (diff)
downloadlinux-f3edacbd697f94a743fff1a3d26910ab99948ba7.tar.bz2
bpf: Revert bpf_overrid_function() helper changes.
NACK'd by x86 maintainer. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'kernel/trace/trace_kprobe.c')
-rw-r--r--kernel/trace/trace_kprobe.c40
1 files changed, 7 insertions, 33 deletions
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 8e3c9ec1faf7..abf92e478cfb 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -42,7 +42,6 @@ struct trace_kprobe {
(offsetof(struct trace_kprobe, tp.args) + \
(sizeof(struct probe_arg) * (n)))
-DEFINE_PER_CPU(int, bpf_kprobe_override);
static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk)
{
@@ -88,12 +87,6 @@ static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk)
return nhit;
}
-int trace_kprobe_ftrace(struct trace_event_call *call)
-{
- struct trace_kprobe *tk = (struct trace_kprobe *)call->data;
- return kprobe_ftrace(&tk->rp.kp);
-}
-
static int register_kprobe_event(struct trace_kprobe *tk);
static int unregister_kprobe_event(struct trace_kprobe *tk);
@@ -1177,7 +1170,7 @@ static int kretprobe_event_define_fields(struct trace_event_call *event_call)
#ifdef CONFIG_PERF_EVENTS
/* Kprobe profile handler */
-static int
+static void
kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
{
struct trace_event_call *call = &tk->tp.call;
@@ -1186,29 +1179,12 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
int size, __size, dsize;
int rctx;
- if (bpf_prog_array_valid(call)) {
- int ret;
-
- ret = trace_call_bpf(call, regs);
-
- /*
- * We need to check and see if we modified the pc of the
- * pt_regs, and if so clear the kprobe and return 1 so that we
- * don't do the instruction skipping. Also reset our state so
- * we are clean the next pass through.
- */
- if (__this_cpu_read(bpf_kprobe_override)) {
- __this_cpu_write(bpf_kprobe_override, 0);
- reset_current_kprobe();
- return 1;
- }
- if (!ret)
- return 0;
- }
+ if (bpf_prog_array_valid(call) && !trace_call_bpf(call, regs))
+ return;
head = this_cpu_ptr(call->perf_events);
if (hlist_empty(head))
- return 0;
+ return;
dsize = __get_data_size(&tk->tp, regs);
__size = sizeof(*entry) + tk->tp.size + dsize;
@@ -1217,14 +1193,13 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
entry = perf_trace_buf_alloc(size, NULL, &rctx);
if (!entry)
- return 0;
+ return;
entry->ip = (unsigned long)tk->rp.kp.addr;
memset(&entry[1], 0, dsize);
store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize);
perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
head, NULL, NULL);
- return 0;
}
NOKPROBE_SYMBOL(kprobe_perf_func);
@@ -1300,7 +1275,6 @@ static int kprobe_register(struct trace_event_call *event,
static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
{
struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp);
- int ret = 0;
raw_cpu_inc(*tk->nhit);
@@ -1308,9 +1282,9 @@ static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
kprobe_trace_func(tk, regs);
#ifdef CONFIG_PERF_EVENTS
if (tk->tp.flags & TP_FLAG_PROFILE)
- ret = kprobe_perf_func(tk, regs);
+ kprobe_perf_func(tk, regs);
#endif
- return ret;
+ return 0; /* We don't tweek kernel, so just return 0 */
}
NOKPROBE_SYMBOL(kprobe_dispatcher);