diff options
Diffstat (limited to 'include/trace/ftrace.h')
| -rw-r--r-- | include/trace/ftrace.h | 59 |
1 files changed, 40 insertions, 19 deletions
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index c9bbcab95fb..4945d1c9986 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -402,12 +402,12 @@ static inline int ftrace_get_offsets_##call( \ \ static void ftrace_profile_##call(proto); \ \ -static int ftrace_profile_enable_##call(void) \ +static int ftrace_profile_enable_##call(struct ftrace_event_call *unused)\ { \ return register_trace_##call(ftrace_profile_##call); \ } \ \ -static void ftrace_profile_disable_##call(void) \ +static void ftrace_profile_disable_##call(struct ftrace_event_call *unused)\ { \ unregister_trace_##call(ftrace_profile_##call); \ } @@ -426,7 +426,7 @@ static void ftrace_profile_disable_##call(void) \ * event_trace_printk(_RET_IP_, "<call>: " <fmt>); * } * - * static int ftrace_reg_event_<call>(void) + * static int ftrace_reg_event_<call>(struct ftrace_event_call *unused) * { * int ret; * @@ -437,7 +437,7 @@ static void ftrace_profile_disable_##call(void) \ * return ret; * } * - * static void ftrace_unreg_event_<call>(void) + * static void ftrace_unreg_event_<call>(struct ftrace_event_call *unused) * { * unregister_trace_<call>(ftrace_event_<call>); * } @@ -472,7 +472,7 @@ static void ftrace_profile_disable_##call(void) \ * trace_current_buffer_unlock_commit(buffer, event, irq_flags, pc); * } * - * static int ftrace_raw_reg_event_<call>(void) + * static int ftrace_raw_reg_event_<call>(struct ftrace_event_call *unused) * { * int ret; * @@ -483,7 +483,7 @@ static void ftrace_profile_disable_##call(void) \ * return ret; * } * - * static void ftrace_unreg_event_<call>(void) + * static void ftrace_unreg_event_<call>(struct ftrace_event_call *unused) * { * unregister_trace_<call>(ftrace_raw_event_<call>); * } @@ -492,7 +492,7 @@ static void ftrace_profile_disable_##call(void) \ * .trace = ftrace_raw_output_<call>, <-- stage 2 * }; * - * static int ftrace_raw_init_event_<call>(void) + * static int ftrace_raw_init_event_<call>(struct ftrace_event_call *unused) * { * int id; * @@ -589,7 +589,7 @@ static void ftrace_raw_event_##call(proto) \ event, irq_flags, pc); \ } \ \ -static int ftrace_raw_reg_event_##call(void *ptr) \ +static int ftrace_raw_reg_event_##call(struct ftrace_event_call *unused)\ { \ int ret; \ \ @@ -600,7 +600,7 @@ static int ftrace_raw_reg_event_##call(void *ptr) \ return ret; \ } \ \ -static void ftrace_raw_unreg_event_##call(void *ptr) \ +static void ftrace_raw_unreg_event_##call(struct ftrace_event_call *unused)\ { \ unregister_trace_##call(ftrace_raw_event_##call); \ } \ @@ -609,7 +609,7 @@ static struct trace_event ftrace_event_type_##call = { \ .trace = ftrace_raw_output_##call, \ }; \ \ -static int ftrace_raw_init_event_##call(void) \ +static int ftrace_raw_init_event_##call(struct ftrace_event_call *unused)\ { \ int id; \ \ @@ -649,6 +649,7 @@ __attribute__((section("_ftrace_events"))) event_##call = { \ * struct ftrace_event_call *event_call = &event_<call>; * extern void perf_tp_event(int, u64, u64, void *, int); * struct ftrace_raw_##call *entry; + * struct perf_trace_buf *trace_buf; * u64 __addr = 0, __count = 1; * unsigned long irq_flags; * struct trace_entry *ent; @@ -673,14 +674,25 @@ __attribute__((section("_ftrace_events"))) event_##call = { \ * __cpu = smp_processor_id(); * * if (in_nmi()) - * raw_data = rcu_dereference(trace_profile_buf_nmi); + * trace_buf = rcu_dereference(perf_trace_buf_nmi); * else - * raw_data = rcu_dereference(trace_profile_buf); + * trace_buf = rcu_dereference(perf_trace_buf); * - * if (!raw_data) + * if (!trace_buf) * goto end; * - * raw_data = per_cpu_ptr(raw_data, __cpu); + * trace_buf = per_cpu_ptr(trace_buf, __cpu); + * + * // Avoid recursion from perf that could mess up the buffer + * if (trace_buf->recursion++) + * goto end_recursion; + * + * raw_data = trace_buf->buf; + * + * // Make recursion update visible before entering perf_tp_event + * // so that we protect from perf recursions. + * + * barrier(); * * //zero dead bytes from alignment to avoid stack leak to userspace: * *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL; @@ -713,8 +725,9 @@ static void ftrace_profile_##call(proto) \ { \ struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\ struct ftrace_event_call *event_call = &event_##call; \ - extern void perf_tp_event(int, u64, u64, void *, int); \ + extern void perf_tp_event(int, u64, u64, void *, int); \ struct ftrace_raw_##call *entry; \ + struct perf_trace_buf *trace_buf; \ u64 __addr = 0, __count = 1; \ unsigned long irq_flags; \ struct trace_entry *ent; \ @@ -739,14 +752,20 @@ static void ftrace_profile_##call(proto) \ __cpu = smp_processor_id(); \ \ if (in_nmi()) \ - raw_data = rcu_dereference(trace_profile_buf_nmi); \ + trace_buf = rcu_dereference(perf_trace_buf_nmi); \ else \ - raw_data = rcu_dereference(trace_profile_buf); \ + trace_buf = rcu_dereference(perf_trace_buf); \ \ - if (!raw_data) \ + if (!trace_buf) \ goto end; \ \ - raw_data = per_cpu_ptr(raw_data, __cpu); \ + trace_buf = per_cpu_ptr(trace_buf, __cpu); \ + if (trace_buf->recursion++) \ + goto end_recursion; \ + \ + barrier(); \ + \ + raw_data = trace_buf->buf; \ \ *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL; \ entry = (struct ftrace_raw_##call *)raw_data; \ @@ -761,6 +780,8 @@ static void ftrace_profile_##call(proto) \ perf_tp_event(event_call->id, __addr, __count, entry, \ __entry_size); \ \ +end_recursion: \ + trace_buf->recursion--; \ end: \ local_irq_restore(irq_flags); \ \ |