cxl: Add tracepoints

This patch adds tracepoints throughout the cxl driver, which can provide
insight into:

- Context lifetimes
- Commands sent to the PSL and AFU and their completion status
- Segment and page table misses and their resolution
- PSL and AFU interrupts
- slbia calls from the powerpc copro_fault code

These tracepoints are mostly intended to aid in debugging (particularly
for new AFU designs), and may be useful standalone or in conjunction
with hardware traces collected by the PSL (read out via the trace
interface in debugfs) and AFUs.

Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/misc/cxl/fault.c b/drivers/misc/cxl/fault.c
index e010302..5286b8b 100644
--- a/drivers/misc/cxl/fault.c
+++ b/drivers/misc/cxl/fault.c
@@ -20,6 +20,7 @@
 #include <asm/mmu.h>
 
 #include "cxl.h"
+#include "trace.h"
 
 static bool sste_matches(struct cxl_sste *sste, struct copro_slb *slb)
 {
@@ -75,6 +76,7 @@ static void cxl_load_segment(struct cxl_context *ctx, struct copro_slb *slb)
 
 	pr_devel("CXL Populating SST[%li]: %#llx %#llx\n",
 			sste - ctx->sstp, slb->vsid, slb->esid);
+	trace_cxl_ste_write(ctx, sste - ctx->sstp, slb->esid, slb->vsid);
 
 	sste->vsid_data = cpu_to_be64(slb->vsid);
 	sste->esid_data = cpu_to_be64(slb->esid);
@@ -116,6 +118,7 @@ static int cxl_handle_segment_miss(struct cxl_context *ctx,
 	int rc;
 
 	pr_devel("CXL interrupt: Segment fault pe: %i ea: %#llx\n", ctx->pe, ea);
+	trace_cxl_ste_miss(ctx, ea);
 
 	if ((rc = cxl_fault_segment(ctx, mm, ea)))
 		cxl_ack_ae(ctx);
@@ -135,6 +138,8 @@ static void cxl_handle_page_fault(struct cxl_context *ctx,
 	int result;
 	unsigned long access, flags, inv_flags = 0;
 
+	trace_cxl_pte_miss(ctx, dsisr, dar);
+
 	if ((result = copro_handle_mm_fault(mm, dar, dsisr, &flt))) {
 		pr_devel("copro_handle_mm_fault failed: %#x\n", result);
 		return cxl_ack_ae(ctx);