[PATCH RFC v4 4/6] cxl/events: Create a CXL event union

From: Ira Weiny
Date: Thu Nov 09 2023 - 17:07:37 EST


The CXL CPER and event log records share everything but a UUID/GUID in
their structures.

Define a cxl_event union without the UUID/GUID to be shared between the
CPER and event log record formats. Adjust the code to use this union.

Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>

---
Changes from RFC v3:
[iweiny: adjust to keeping uuid in trace events]

Changes from RFC v2:
[iweiny: new patch]
---
drivers/cxl/core/mbox.c | 32 +++++++++++++-------------------
drivers/cxl/core/trace.h | 8 ++++----
include/linux/cxl-event.h | 23 +++++++++++++++++------
tools/testing/cxl/test/mem.c | 31 ++++++++++++++++++-------------
4 files changed, 52 insertions(+), 42 deletions(-)

diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index 74446c6a990a..ac44f3659d84 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -864,26 +864,17 @@ static void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
enum cxl_event_log_type type,
struct cxl_event_record_raw *record)
{
+ union cxl_event *evt = &record->event;
uuid_t *id = &record->id;

- if (uuid_equal(id, &gen_media_event_uuid)) {
- struct cxl_event_gen_media *rec =
- (struct cxl_event_gen_media *)record;
-
- trace_cxl_general_media(cxlmd, type, id, rec);
- } else if (uuid_equal(id, &dram_event_uuid)) {
- struct cxl_event_dram *rec = (struct cxl_event_dram *)record;
-
- trace_cxl_dram(cxlmd, type, id, rec);
- } else if (uuid_equal(id, &mem_mod_event_uuid)) {
- struct cxl_event_mem_module *rec =
- (struct cxl_event_mem_module *)record;
-
- trace_cxl_memory_module(cxlmd, type, id, rec);
- } else {
- /* For unknown record types print just the header */
- trace_cxl_generic_event(cxlmd, type, id, record);
- }
+ if (uuid_equal(id, &gen_media_event_uuid))
+ trace_cxl_general_media(cxlmd, type, id, &evt->gen_media);
+ else if (uuid_equal(id, &dram_event_uuid))
+ trace_cxl_dram(cxlmd, type, id, &evt->dram);
+ else if (uuid_equal(id, &mem_mod_event_uuid))
+ trace_cxl_memory_module(cxlmd, type, id, &evt->mem_module);
+ else
+ trace_cxl_generic_event(cxlmd, type, id, &evt->generic);
}

static int cxl_clear_event_record(struct cxl_memdev_state *mds,
@@ -926,7 +917,10 @@ static int cxl_clear_event_record(struct cxl_memdev_state *mds,
*/
i = 0;
for (cnt = 0; cnt < total; cnt++) {
- payload->handles[i++] = get_pl->records[cnt].hdr.handle;
+ struct cxl_event_record_raw *raw = &get_pl->records[cnt];
+ struct cxl_event_generic *gen = &raw->event.generic;
+
+ payload->handles[i++] = gen->hdr.handle;
dev_dbg(mds->cxlds.dev, "Event log '%d': Clearing %u\n", log,
le16_to_cpu(payload->handles[i]));

diff --git a/drivers/cxl/core/trace.h b/drivers/cxl/core/trace.h
index 2aef185f4cd0..3d007f0472f2 100644
--- a/drivers/cxl/core/trace.h
+++ b/drivers/cxl/core/trace.h
@@ -225,9 +225,9 @@ TRACE_EVENT(cxl_overflow,
TRACE_EVENT(cxl_generic_event,

TP_PROTO(const struct cxl_memdev *cxlmd, enum cxl_event_log_type log,
- const uuid_t *uuid, struct cxl_event_record_raw *rec),
+ const uuid_t *uuid, struct cxl_event_generic *gen_rec),

- TP_ARGS(cxlmd, log, uuid, rec),
+ TP_ARGS(cxlmd, log, uuid, gen_rec),

TP_STRUCT__entry(
CXL_EVT_TP_entry
@@ -235,8 +235,8 @@ TRACE_EVENT(cxl_generic_event,
),

TP_fast_assign(
- CXL_EVT_TP_fast_assign(cxlmd, log, uuid, rec->hdr);
- memcpy(__entry->data, &rec->data, CXL_EVENT_RECORD_DATA_LENGTH);
+ CXL_EVT_TP_fast_assign(cxlmd, log, uuid, gen_rec->hdr);
+ memcpy(__entry->data, gen_rec->data, CXL_EVENT_RECORD_DATA_LENGTH);
),

CXL_EVT_TP_printk("%s",
diff --git a/include/linux/cxl-event.h b/include/linux/cxl-event.h
index ebb00ead1496..6b689e1efc78 100644
--- a/include/linux/cxl-event.h
+++ b/include/linux/cxl-event.h
@@ -18,13 +18,8 @@ struct cxl_event_record_hdr {
u8 reserved[15];
} __packed;

-/*
- * Common Event Record Format
- * CXL rev 3.0 section 8.2.9.2.1; Table 8-42
- */
#define CXL_EVENT_RECORD_DATA_LENGTH 0x50
-struct cxl_event_record_raw {
- uuid_t id;
+struct cxl_event_generic {
struct cxl_event_record_hdr hdr;
u8 data[CXL_EVENT_RECORD_DATA_LENGTH];
} __packed;
@@ -97,4 +92,20 @@ struct cxl_event_mem_module {
u8 reserved[0x3d];
} __packed;

+union cxl_event {
+ struct cxl_event_generic generic;
+ struct cxl_event_gen_media gen_media;
+ struct cxl_event_dram dram;
+ struct cxl_event_mem_module mem_module;
+};
+
+/*
+ * Common Event Record Format; in event logs
+ * CXL rev 3.0 section 8.2.9.2.1; Table 8-42
+ */
+struct cxl_event_record_raw {
+ uuid_t id;
+ union cxl_event event;
+} __packed;
+
#endif /* _LINUX_CXL_EVENT_H */
diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c
index 85862be00c48..2535eb182ece 100644
--- a/tools/testing/cxl/test/mem.c
+++ b/tools/testing/cxl/test/mem.c
@@ -244,7 +244,8 @@ static int mock_get_event(struct device *dev, struct cxl_mbox_cmd *cmd)
for (i = 0; i < CXL_TEST_EVENT_CNT && !event_log_empty(log); i++) {
memcpy(&pl->records[i], event_get_current(log),
sizeof(pl->records[i]));
- pl->records[i].hdr.handle = event_get_cur_event_handle(log);
+ pl->records[i].event.generic.hdr.handle =
+ event_get_cur_event_handle(log);
log->cur_idx++;
}

@@ -332,25 +333,29 @@ static void cxl_mock_event_trigger(struct device *dev)
struct cxl_event_record_raw maint_needed = {
.id = UUID_INIT(0xBA5EBA11, 0xABCD, 0xEFEB,
0xa5, 0x5a, 0xa5, 0x5a, 0xa5, 0xa5, 0x5a, 0xa5),
- .hdr = {
- .length = sizeof(struct cxl_event_record_raw),
- .flags[0] = CXL_EVENT_RECORD_FLAG_MAINT_NEEDED,
- /* .handle = Set dynamically */
- .related_handle = cpu_to_le16(0xa5b6),
+ .event.generic = {
+ .hdr = {
+ .length = sizeof(struct cxl_event_record_raw),
+ .flags[0] = CXL_EVENT_RECORD_FLAG_MAINT_NEEDED,
+ /* .handle = Set dynamically */
+ .related_handle = cpu_to_le16(0xa5b6),
+ },
+ .data = { 0xDE, 0xAD, 0xBE, 0xEF },
},
- .data = { 0xDE, 0xAD, 0xBE, 0xEF },
};

struct cxl_event_record_raw hardware_replace = {
.id = UUID_INIT(0xABCDEFEB, 0xBA11, 0xBA5E,
0xa5, 0x5a, 0xa5, 0x5a, 0xa5, 0xa5, 0x5a, 0xa5),
- .hdr = {
- .length = sizeof(struct cxl_event_record_raw),
- .flags[0] = CXL_EVENT_RECORD_FLAG_HW_REPLACE,
- /* .handle = Set dynamically */
- .related_handle = cpu_to_le16(0xb6a5),
+ .event.generic = {
+ .hdr = {
+ .length = sizeof(struct cxl_event_record_raw),
+ .flags[0] = CXL_EVENT_RECORD_FLAG_HW_REPLACE,
+ /* .handle = Set dynamically */
+ .related_handle = cpu_to_le16(0xb6a5),
+ },
+ .data = { 0xDE, 0xAD, 0xBE, 0xEF },
},
- .data = { 0xDE, 0xAD, 0xBE, 0xEF },
};

struct cxl_test_gen_media {

--
2.41.0