[tip: x86/cpu] tracing: Add the ::microcode field to the mce_record tracepoint

[tip-bot2 for Avadhut Naik]

The following commit has been merged into the x86/cpu branch of tip:

Commit-ID:     186d7ef52c1f0c41450dedbdf6d6325d0a84e4c5
Gitweb:        https://git.kernel.org/tip/186d7ef52c1f0c41450dedbdf6d6325d0a84e4c5
Author:        Avadhut Naik <avadhut.naik@xxxxxxx>
AuthorDate:    Mon, 01 Apr 2024 12:14:55 -05:00
Committer:     Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Wed, 03 Apr 2024 09:39:29 +02:00

tracing: Add the ::microcode field to the mce_record tracepoint

Currently, the microcode field (Microcode Revision) of 'struct mce' is not
exposed to userspace through the mce_record tracepoint.

Knowing the microcode version on which the MCE was received is critical
information for debugging. If the version is not recorded, later attempts
to acquire the version might result in discrepancies since it can be
changed at runtime.

Add microcode version to the tracepoint to prevent ambiguity over
the active version on the system when the MCE was received.

Signed-off-by: Avadhut Naik <avadhut.naik@xxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Reviewed-by: Sohil Mehta <sohil.mehta@xxxxxxxxx>
Reviewed-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx>
Link: https://lore.kernel.org/r/20240401171455.1737976-3-avadhut.naik@xxxxxxx
---
 include/trace/events/mce.h | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/include/trace/events/mce.h b/include/trace/events/mce.h
index 294fccc..f0f7b3c 100644
--- a/include/trace/events/mce.h
+++ b/include/trace/events/mce.h
@@ -42,6 +42,7 @@ TRACE_EVENT(mce_record,
 		__field(	u8,		cs		)
 		__field(	u8,		bank		)
 		__field(	u8,		cpuvendor	)
+		__field(	u32,		microcode	)
 	),
 
 	TP_fast_assign(
@@ -63,9 +64,10 @@ TRACE_EVENT(mce_record,
 		__entry->cs		= m->cs;
 		__entry->bank		= m->bank;
 		__entry->cpuvendor	= m->cpuvendor;
+		__entry->microcode	= m->microcode;
 	),
 
-	TP_printk("CPU: %d, MCGc/s: %llx/%llx, MC%d: %016Lx, IPID: %016Lx, ADDR: %016Lx, MISC: %016Lx, SYND: %016Lx, RIP: %02x:<%016Lx>, TSC: %llx, PPIN: %llx, vendor: %u, CPUID: %x, time: %llu, socket: %u, APIC: %x",
+	TP_printk("CPU: %d, MCGc/s: %llx/%llx, MC%d: %016Lx, IPID: %016Lx, ADDR: %016Lx, MISC: %016Lx, SYND: %016Lx, RIP: %02x:<%016Lx>, TSC: %llx, PPIN: %llx, vendor: %u, CPUID: %x, time: %llu, socket: %u, APIC: %x, microcode: %x",
 		__entry->cpu,
 		__entry->mcgcap, __entry->mcgstatus,
 		__entry->bank, __entry->status,
@@ -80,7 +82,8 @@ TRACE_EVENT(mce_record,
 		__entry->cpuid,
 		__entry->walltime,
 		__entry->socketid,
-		__entry->apicid)
+		__entry->apicid,
+		__entry->microcode)
 );
 
 #endif /* _TRACE_MCE_H */