Re: [PATCH V2 02/11] cxl/mem: Implement Get Event Records command

Steven Rostedt
2022-12-01T17:39:04Z

On Wed, 30 Nov 2022 16:27:10 -0800
ira.weiny@intel.com wrote:

> CONEXANT ACCESSRUNNER USB DRIVER
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index 16176b9278b4..70b681027a3d 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -7,6 +7,9 @@
> #include <cxlmem.h>
> #include <cxl.h>
>
> +#define CREATE_TRACE_POINTS
> +#include <trace/events/cxl.h>
> +
> #include "core.h"
>
> static bool cxl_raw_allow_all;
> @@ -48,6 +51,7 @@ static struct cxl_mem_command cxl_mem_commands[CXL_MEM_COMMAND_ID_MAX] = {
> CXL_CMD(RAW, CXL_VARIABLE_PAYLOAD, CXL_VARIABLE_PAYLOAD, 0),
> #endif
> CXL_CMD(GET_SUPPORTED_LOGS, 0, CXL_VARIABLE_PAYLOAD, CXL_CMD_FLAG_FORCE_ENABLE),
> + CXL_CMD(GET_EVENT_RECORD, 1, CXL_VARIABLE_PAYLOAD, 0),
> CXL_CMD(GET_FW_INFO, 0, 0x50, 0),
> CXL_CMD(GET_PARTITION_INFO, 0, 0x20, 0),
> CXL_CMD(GET_LSA, 0x8, CXL_VARIABLE_PAYLOAD, 0),
> @@ -704,6 +708,106 @@ int cxl_enumerate_cmds(struct cxl_dev_state *cxlds)
> }
> EXPORT_SYMBOL_NS_GPL(cxl_enumerate_cmds, CXL);
>
> +static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
> + enum cxl_event_log_type type)
> +{
> + struct cxl_get_event_payload *payload;
> + u16 nr_rec;
> +
> + mutex_lock(&cxlds->event_buf_lock);
> +
> + payload = cxlds->event_buf;
> +
> + do {
> + u8 log_type = type;
> + int rc;
> +
> + rc = cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_GET_EVENT_RECORD,
> + &log_type, sizeof(log_type),
> + payload, cxlds->payload_size);
> + if (rc) {
> + dev_err(cxlds->dev, "Event log '%s': Failed to query event records : %d",
> + cxl_event_log_type_str(type), rc);
> + goto unlock_buffer;
> + }
> +
> + nr_rec = le16_to_cpu(payload->record_count);
> + if (trace_cxl_generic_event_enabled()) {
> + int i;
> +
> + for (i = 0; i < nr_rec; i++)
> + trace_cxl_generic_event(dev_name(cxlds->dev),
> + type,
> + &payload->records[i]);
> + }
> +
> + if (trace_cxl_overflow_enabled() &&
> + (payload->flags & CXL_GET_EVENT_FLAG_OVERFLOW))
> + trace_cxl_overflow(dev_name(cxlds->dev), type, payload);
> +
> + } while (nr_rec);
> +
> +unlock_buffer:
> + mutex_unlock(&cxlds->event_buf_lock);
> +}
> +
> +static void cxl_mem_free_event_buffer(void *data)
> +{
> + struct cxl_dev_state *cxlds = data;
> +
> + kvfree(cxlds->event_buf);
> +}
> +
> +/*
> + * There is a single buffer for reading event logs from the mailbox. All logs
> + * share this buffer protected by the cxlds->event_buf_lock.
> + */
> +static struct cxl_get_event_payload *alloc_event_buf(struct cxl_dev_state *cxlds)
> +{
> + struct cxl_get_event_payload *buf;
> +
> + dev_dbg(cxlds->dev, "Allocating event buffer size %zu\n",
> + cxlds->payload_size);
> +
> + buf = kvmalloc(cxlds->payload_size, GFP_KERNEL);
> + if (buf && devm_add_action_or_reset(cxlds->dev,
> + cxl_mem_free_event_buffer, cxlds))
> + return NULL;
> + return buf;
> +}
> +
> +/**
> + * cxl_mem_get_event_records - Get Event Records from the device
> + * @cxlds: The device data for the operation
> + *
> + * Retrieve all event records available on the device and report them as trace
> + * events.
> + *
> + * See CXL rev 3.0 @8.2.9.2.2 Get Event Records
> + */
> +void cxl_mem_get_event_records(struct cxl_dev_state *cxlds)
> +{
> + u32 status = readl(cxlds->regs.status + CXLDEV_DEV_EVENT_STATUS_OFFSET);
> +
> + dev_dbg(cxlds->dev, "Reading event logs: %x\n", status);
> +
> + if (!cxlds->event_buf) {
> + cxlds->event_buf = alloc_event_buf(cxlds);
> + if (WARN_ON_ONCE(!cxlds->event_buf))
> + return;
> + }
> +
> + if (status & CXLDEV_EVENT_STATUS_INFO)
> + cxl_mem_get_records_log(cxlds, CXL_EVENT_TYPE_INFO);
> + if (status & CXLDEV_EVENT_STATUS_WARN)
> + cxl_mem_get_records_log(cxlds, CXL_EVENT_TYPE_WARN);
> + if (status & CXLDEV_EVENT_STATUS_FAIL)
> + cxl_mem_get_records_log(cxlds, CXL_EVENT_TYPE_FAIL);
> + if (status & CXLDEV_EVENT_STATUS_FATAL)
> + cxl_mem_get_records_log(cxlds, CXL_EVENT_TYPE_FATAL);
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_mem_get_event_records, CXL);
> +
> /**
> * cxl_mem_get_partition_info - Get partition info
> * @cxlds: The device data for the operation
> @@ -846,6 +950,7 @@ struct cxl_dev_state *cxl_dev_state_create(struct device *dev)
> }
>
> mutex_init(&cxlds->mbox_mutex);
> + mutex_init(&cxlds->event_buf_lock);
> cxlds->dev = dev;
>
> return cxlds;
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index f680450f0b16..d4baae74cd97 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -132,6 +132,13 @@ static inline int ways_to_cxl(unsigned int ways, u8 *iw)
> #define CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX 0x3
> #define CXLDEV_CAP_CAP_ID_MEMDEV 0x4000
>
> +/* CXL 3.0 8.2.8.3.1 Event Status Register */
> +#define CXLDEV_DEV_EVENT_STATUS_OFFSET 0x00
> +#define CXLDEV_EVENT_STATUS_INFO BIT(0)
> +#define CXLDEV_EVENT_STATUS_WARN BIT(1)
> +#define CXLDEV_EVENT_STATUS_FAIL BIT(2)
> +#define CXLDEV_EVENT_STATUS_FATAL BIT(3)
> +
> /* CXL 2.0 8.2.8.4 Mailbox Registers */
> #define CXLDEV_MBOX_CAPS_OFFSET 0x00
> #define CXLDEV_MBOX_CAP_PAYLOAD_SIZE_MASK GENMASK(4, 0)
> diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> index cd35f43fedd4..55d57f5a64bc 100644
> --- a/drivers/cxl/cxlmem.h
> +++ b/drivers/cxl/cxlmem.h
> @@ -4,6 +4,7 @@
> #define __CXL_MEM_H__
> #include <uapi/linux/cxl_mem.h>
> #include <linux/cdev.h>
> +#include <linux/uuid.h>
> #include "cxl.h"
>
> /* CXL 2.0 8.2.8.5.1.1 Memory Device Status Register */
> @@ -250,12 +251,16 @@ struct cxl_dev_state {
>
> bool msi_enabled;
>
> + struct cxl_get_event_payload *event_buf;
> + struct mutex event_buf_lock;
> +
> int (*mbox_send)(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd);
> };
>
> enum cxl_opcode {
> CXL_MBOX_OP_INVALID = 0x0000,
> CXL_MBOX_OP_RAW = CXL_MBOX_OP_INVALID,
> + CXL_MBOX_OP_GET_EVENT_RECORD = 0x0100,
> CXL_MBOX_OP_GET_FW_INFO = 0x0200,
> CXL_MBOX_OP_ACTIVATE_FW = 0x0202,
> CXL_MBOX_OP_GET_SUPPORTED_LOGS = 0x0400,
> @@ -325,6 +330,72 @@ struct cxl_mbox_identify {
> u8 qos_telemetry_caps;
> } __packed;
>
> +/*
> + * Common Event Record Format
> + * CXL rev 3.0 section 8.2.9.2.1; Table 8-42
> + */
> +struct cxl_event_record_hdr {
> + uuid_t id;
> + u8 length;
> + u8 flags[3];
> + __le16 handle;
> + __le16 related_handle;
> + __le64 timestamp;
> + u8 maint_op_class;
> + u8 reserved[0xf];
> +} __packed;
> +
> +#define CXL_EVENT_RECORD_DATA_LENGTH 0x50
> +struct cxl_event_record_raw {
> + struct cxl_event_record_hdr hdr;
> + u8 data[CXL_EVENT_RECORD_DATA_LENGTH];
> +} __packed;
> +
> +/*
> + * Get Event Records output payload
> + * CXL rev 3.0 section 8.2.9.2.2; Table 8-50
> + */
> +#define CXL_GET_EVENT_FLAG_OVERFLOW BIT(0)
> +#define CXL_GET_EVENT_FLAG_MORE_RECORDS BIT(1)
> +struct cxl_get_event_payload {
> + u8 flags;
> + u8 reserved1;
> + __le16 overflow_err_count;
> + __le64 first_overflow_timestamp;
> + __le64 last_overflow_timestamp;
> + __le16 record_count;
> + u8 reserved2[0xa];
> + struct cxl_event_record_raw records[];
> +} __packed;
> +
> +/*
> + * CXL rev 3.0 section 8.2.9.2.2; Table 8-49
> + */
> +enum cxl_event_log_type {
> + CXL_EVENT_TYPE_INFO = 0x00,
> + CXL_EVENT_TYPE_WARN,
> + CXL_EVENT_TYPE_FAIL,
> + CXL_EVENT_TYPE_FATAL,
> + CXL_EVENT_TYPE_MAX
> +};
> +
> +static inline const char *cxl_event_log_type_str(enum cxl_event_log_type type)
> +{
> + switch (type) {
> + case CXL_EVENT_TYPE_INFO:
> + return "Informational";
> + case CXL_EVENT_TYPE_WARN:
> + return "Warning";
> + case CXL_EVENT_TYPE_FAIL:
> + return "Failure";
> + case CXL_EVENT_TYPE_FATAL:
> + return "Fatal";
> + default:
> + break;
> + }
> + return "<unknown>";
> +}

So you are using this in a TP_printk() section, which means perf and
trace-cmd have no idea how to parse it. Can I recommend instead having:

#define cxl_event_log_type_str(type) \
__print_symbolic(type, \
{ CXL_EVENT_TYPE_INFO, "Informational" }, \
{ CXL_EVENT_TYPE_WARN, "Warning" }, \
{ CXL_EVENT_TYPE_FAIL, "Failure" }, \
{ CXL_EVENT_TYPE_FATAL, "Fatal" })

#ifndef CREATE_TRACE_POINTS
static inline const char *__cxl_event_log_type_str(enum cxl_event_log_type type,
struct trace_print_flags *symbols)
{
for (; symbols->mask >= 0; symbols++) {
if (type == symbols->mask)
return symbols->name;
}
return "<unknown>";
}
#define __print_symbolic(value, symbol_array...) \
({ \
static const struct trace_print_flags symbols[] = \
{ symbol_array, { -1, NULL }}; \
__cxl_event_log_type_str(value, symbols); \
})
#endif

Note, I did not even try to compile the above. But it should be close to
working.

This way, the cxl_event_log_type_str() for trace events will be converted
into the __print_symbolic() which can be parsed by perf and trace-cmd. For
all other use cases, it is converted into the function above to return the
string.

-- Steve

> +
> struct cxl_mbox_get_partition_info {
> __le64 active_volatile_cap;
> __le64 active_persistent_cap;
> @@ -384,6 +455,7 @@ int cxl_mem_create_range_info(struct cxl_dev_state *cxlds);
> struct cxl_dev_state *cxl_dev_state_create(struct device *dev);
> void set_exclusive_cxl_commands(struct cxl_dev_state *cxlds, unsigned long *cmds);
> void clear_exclusive_cxl_commands(struct cxl_dev_state *cxlds, unsigned long *cmds);
> +void cxl_mem_get_event_records(struct cxl_dev_state *cxlds);
> #ifdef CONFIG_CXL_SUSPEND
> void cxl_mem_active_inc(void);
> void cxl_mem_active_dec(void);
> diff --git a/include/trace/events/cxl.h b/include/trace/events/cxl.h
> new file mode 100644
> index 000000000000..c03a1a894af8
> --- /dev/null
> +++ b/include/trace/events/cxl.h
> @@ -0,0 +1,126 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#undef TRACE_SYSTEM
> +#define TRACE_SYSTEM cxl
> +
> +#if !defined(_CXL_TRACE_EVENTS_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define _CXL_TRACE_EVENTS_H
> +
> +#include <asm-generic/unaligned.h>
> +#include <linux/tracepoint.h>
> +#include <cxlmem.h>
> +
> +TRACE_EVENT(cxl_overflow,
> +
> + TP_PROTO(const char *dev_name, enum cxl_event_log_type log,
> + struct cxl_get_event_payload *payload),
> +
> + TP_ARGS(dev_name, log, payload),
> +
> + TP_STRUCT__entry(
> + __string(dev_name, dev_name)
> + __field(int, log)
> + __field(u64, first_ts)
> + __field(u64, last_ts)
> + __field(u16, count)
> + ),
> +
> + TP_fast_assign(
> + __assign_str(dev_name, dev_name);
> + __entry->log = log;
> + __entry->count = le16_to_cpu(payload->overflow_err_count);
> + __entry->first_ts = le64_to_cpu(payload->first_overflow_timestamp);
> + __entry->last_ts = le64_to_cpu(payload->last_overflow_timestamp);
> + ),
> +
> + TP_printk("%s: EVENT LOG OVERFLOW log=%s : %u records from %llu to %llu",
> + __get_str(dev_name), cxl_event_log_type_str(__entry->log),
> + __entry->count, __entry->first_ts, __entry->last_ts)
> +
> +);
> +
> +/*
> + * Common Event Record Format
> + * CXL 3.0 section 8.2.9.2.1; Table 8-42
> + */
> +#define CXL_EVENT_RECORD_FLAG_PERMANENT BIT(2)
> +#define CXL_EVENT_RECORD_FLAG_MAINT_NEEDED BIT(3)
> +#define CXL_EVENT_RECORD_FLAG_PERF_DEGRADED BIT(4)
> +#define CXL_EVENT_RECORD_FLAG_HW_REPLACE BIT(5)
> +#define show_hdr_flags(flags) __print_flags(flags, " | ", \
> + { CXL_EVENT_RECORD_FLAG_PERMANENT, "PERMANENT_CONDITION" }, \
> + { CXL_EVENT_RECORD_FLAG_MAINT_NEEDED, "MAINTENANCE_NEEDED" }, \
> + { CXL_EVENT_RECORD_FLAG_PERF_DEGRADED, "PERFORMANCE_DEGRADED" }, \
> + { CXL_EVENT_RECORD_FLAG_HW_REPLACE, "HARDWARE_REPLACEMENT_NEEDED" } \
> +)
> +
> +/*
> + * Define macros for the common header of each CXL event.
> + *
> + * Tracepoints using these macros must do 3 things:
> + *
> + * 1) Add CXL_EVT_TP_entry to TP_STRUCT__entry
> + * 2) Use CXL_EVT_TP_fast_assign within TP_fast_assign;
> + * pass the dev_name, log, and CXL event header
> + * 3) Use CXL_EVT_TP_printk() instead of TP_printk()
> + *
> + * See the generic_event tracepoint as an example.
> + */
> +#define CXL_EVT_TP_entry \
> + __string(dev_name, dev_name) \
> + __field(int, log) \
> + __field_struct(uuid_t, hdr_uuid) \
> + __field(u32, hdr_flags) \
> + __field(u16, hdr_handle) \
> + __field(u16, hdr_related_handle) \
> + __field(u64, hdr_timestamp) \
> + __field(u8, hdr_length) \
> + __field(u8, hdr_maint_op_class)
> +
> +#define CXL_EVT_TP_fast_assign(dname, l, hdr) \
> + __assign_str(dev_name, (dname)); \
> + __entry->log = (l); \
> + memcpy(&__entry->hdr_uuid, &(hdr).id, sizeof(uuid_t)); \
> + __entry->hdr_length = (hdr).length; \
> + __entry->hdr_flags = get_unaligned_le24((hdr).flags); \
> + __entry->hdr_handle = le16_to_cpu((hdr).handle); \
> + __entry->hdr_related_handle = le16_to_cpu((hdr).related_handle); \
> + __entry->hdr_timestamp = le64_to_cpu((hdr).timestamp); \
> + __entry->hdr_maint_op_class = (hdr).maint_op_class
> +
> +#define CXL_EVT_TP_printk(fmt, ...) \
> + TP_printk("%s log=%s : time=%llu uuid=%pUb len=%d flags='%s' " \
> + "handle=%x related_handle=%x maint_op_class=%u" \
> + " : " fmt, \
> + __get_str(dev_name), cxl_event_log_type_str(__entry->log), \
> + __entry->hdr_timestamp, &__entry->hdr_uuid, __entry->hdr_length,\
> + show_hdr_flags(__entry->hdr_flags), __entry->hdr_handle, \
> + __entry->hdr_related_handle, __entry->hdr_maint_op_class, \
> + ##__VA_ARGS__)
> +
> +TRACE_EVENT(cxl_generic_event,
> +
> + TP_PROTO(const char *dev_name, enum cxl_event_log_type log,
> + struct cxl_event_record_raw *rec),
> +
> + TP_ARGS(dev_name, log, rec),
> +
> + TP_STRUCT__entry(
> + CXL_EVT_TP_entry
> + __array(u8, data, CXL_EVENT_RECORD_DATA_LENGTH)
> + ),
> +
> + TP_fast_assign(
> + CXL_EVT_TP_fast_assign(dev_name, log, rec->hdr);
> + memcpy(__entry->data, &rec->data, CXL_EVENT_RECORD_DATA_LENGTH);
> + ),
> +
> + CXL_EVT_TP_printk("%s",
> + __print_hex(__entry->data, CXL_EVENT_RECORD_DATA_LENGTH))
> +);
> +
> +#endif /* _CXL_TRACE_EVENTS_H */
> +
> +/* This part must be outside protection */
> +#undef TRACE_INCLUDE_FILE
> +#define TRACE_INCLUDE_FILE cxl
> +#include <trace/define_trace.h>
> diff --git a/include/uapi/linux/cxl_mem.h b/include/uapi/linux/cxl_mem.h
> index c71021a2a9ed..70459be5bdd4 100644
> --- a/include/uapi/linux/cxl_mem.h
> +++ b/include/uapi/linux/cxl_mem.h
> @@ -24,6 +24,7 @@
> ___C(IDENTIFY, "Identify Command"), \
> ___C(RAW, "Raw device command"), \
> ___C(GET_SUPPORTED_LOGS, "Get Supported Logs"), \
> + ___C(GET_EVENT_RECORD, "Get Event Record"), \
> ___C(GET_FW_INFO, "Get FW Info"), \
> ___C(GET_PARTITION_INFO, "Get Partition Information"), \
> ___C(GET_LSA, "Get Label Storage Area"), \