[RFC 10/10] trace: platform/x86/intel/ifs: Add trace point to track Intel IFS operations

[Jithu Joseph <jithu.joseph@intel.com>]

From: Tony Luck <tony.luck@intel.com>

Add tracing support which may be useful for debugging systems that fail to complete
In Field Scan tests.

Signed-off-by: Tony Luck <tony.luck@intel.com>
---
 drivers/platform/x86/intel/ifs/core.c |  5 ++++
 include/trace/events/ifs.h            | 38 +++++++++++++++++++++++++++
 2 files changed, 43 insertions(+)
 create mode 100644 include/trace/events/ifs.h

diff --git a/drivers/platform/x86/intel/ifs/core.c b/drivers/platform/x86/intel/ifs/core.c
index c9ca385082e9..dec2a72eb95a 100644
--- a/drivers/platform/x86/intel/ifs/core.c
+++ b/drivers/platform/x86/intel/ifs/core.c
@@ -13,6 +13,9 @@
 
 #include "ifs.h"
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/ifs.h>
+
 static enum cpuhp_state cpuhp_scan_state;
 struct ifs_params ifs_params;
 int cpu_sibl_ct;
@@ -217,6 +220,8 @@ static int scan_test_worker(void *info)
 
 			rdmsrl(MSR_SCAN_STATUS, status.data);
 
+			trace_ifs_status(activate, status);
+
 			/* Some cases can be retried, give up for others */
 			if (!can_restart(status))
 				break;
diff --git a/include/trace/events/ifs.h b/include/trace/events/ifs.h
new file mode 100644
index 000000000000..3c6ef33c7b3b
--- /dev/null
+++ b/include/trace/events/ifs.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM ifs
+
+#if !defined(_TRACE_IFS_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_IFS_H
+
+#include <linux/ktime.h>
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(ifs_status,
+
+	TP_PROTO(union ifs_scan activate, union ifs_status status),
+
+	TP_ARGS(activate, status),
+
+	TP_STRUCT__entry(
+		__field(	u8,	start	)
+		__field(	u8,	stop	)
+		__field(	u64,	status	)
+	),
+
+	TP_fast_assign(
+		__entry->start	= activate.start;
+		__entry->stop	= activate.stop;
+		__entry->status	= status.data;
+	),
+
+	TP_printk("start: %.2x, stop: %.2x, status: %llx",
+		__entry->start,
+		__entry->stop,
+		__entry->status)
+);
+
+#endif /* _TRACE_IFS_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
-- 
2.17.1