[for-linus][PATCH 02/15] tracing: Make synth_event trace functions endian-correct

[Steven Rostedt <rostedt@goodmis.org>]

From: Tom Zanussi <zanussi@kernel.org>

synth_event_trace(), synth_event_trace_array() and
__synth_event_add_val() write directly into the trace buffer and need
to take endianness into account, like trace_event_raw_event_synth()
does.

Link: http://lkml.kernel.org/r/2011354355e405af9c9d28abba430d1f5ff7771a.1581720155.git.zanussi@kernel.org

Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 kernel/trace/trace_events_hist.c | 62 +++++++++++++++++++++++++++++---
 1 file changed, 58 insertions(+), 4 deletions(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 65b54d6a1422..6a380fb83864 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1891,7 +1891,25 @@ int synth_event_trace(struct trace_event_file *file, unsigned int n_vals, ...)
 			strscpy(str_field, str_val, STR_VAR_LEN_MAX);
 			n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
 		} else {
-			state.entry->fields[n_u64] = val;
+			struct synth_field *field = state.event->fields[i];
+
+			switch (field->size) {
+			case 1:
+				*(u8 *)&state.entry->fields[n_u64] = (u8)val;
+				break;
+
+			case 2:
+				*(u16 *)&state.entry->fields[n_u64] = (u16)val;
+				break;
+
+			case 4:
+				*(u32 *)&state.entry->fields[n_u64] = (u32)val;
+				break;
+
+			default:
+				state.entry->fields[n_u64] = val;
+				break;
+			}
 			n_u64++;
 		}
 	}
@@ -1943,7 +1961,26 @@ int synth_event_trace_array(struct trace_event_file *file, u64 *vals,
 			strscpy(str_field, str_val, STR_VAR_LEN_MAX);
 			n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
 		} else {
-			state.entry->fields[n_u64] = vals[i];
+			struct synth_field *field = state.event->fields[i];
+			u64 val = vals[i];
+
+			switch (field->size) {
+			case 1:
+				*(u8 *)&state.entry->fields[n_u64] = (u8)val;
+				break;
+
+			case 2:
+				*(u16 *)&state.entry->fields[n_u64] = (u16)val;
+				break;
+
+			case 4:
+				*(u32 *)&state.entry->fields[n_u64] = (u32)val;
+				break;
+
+			default:
+				state.entry->fields[n_u64] = val;
+				break;
+			}
 			n_u64++;
 		}
 	}
@@ -2062,8 +2099,25 @@ static int __synth_event_add_val(const char *field_name, u64 val,
 
 		str_field = (char *)&entry->fields[field->offset];
 		strscpy(str_field, str_val, STR_VAR_LEN_MAX);
-	} else
-		entry->fields[field->offset] = val;
+	} else {
+		switch (field->size) {
+		case 1:
+			*(u8 *)&trace_state->entry->fields[field->offset] = (u8)val;
+			break;
+
+		case 2:
+			*(u16 *)&trace_state->entry->fields[field->offset] = (u16)val;
+			break;
+
+		case 4:
+			*(u32 *)&trace_state->entry->fields[field->offset] = (u32)val;
+			break;
+
+		default:
+			trace_state->entry->fields[field->offset] = val;
+			break;
+		}
+	}
  out:
 	return ret;
 }
-- 
2.25.0