Re: [PATCH v2 3/4] cxl: Add extended linear cache address alias emission for cxl events

Dave Jiang
2025-01-10T17:29:08Z

On 1/10/25 8:17 AM, Dave Jiang wrote:
> Add the aliased address of extended linear cache when emitting event
> trace for DRAM and general media of CXL events.
>
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> ---
> v2:
> - Emit hpa_alias0 instead of hpa_alias. (Jonathan)
> - Check valid cxlr before dereference. (Jonathan)
> ---
> drivers/cxl/core/core.h | 5 +++++
> drivers/cxl/core/mbox.c | 33 +++++++++++++++++++++++++++++----
> drivers/cxl/core/region.c | 12 ++++++++++++
> drivers/cxl/core/trace.h | 24 ++++++++++++++++--------
> 4 files changed, 62 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
> index 0fb779b612d1..afbefc72c8fa 100644
> --- a/drivers/cxl/core/core.h
> +++ b/drivers/cxl/core/core.h
> @@ -30,8 +30,13 @@ int cxl_get_poison_by_endpoint(struct cxl_port *port);
> struct cxl_region *cxl_dpa_to_region(const struct cxl_memdev *cxlmd, u64 dpa);
> u64 cxl_dpa_to_hpa(struct cxl_region *cxlr, const struct cxl_memdev *cxlmd,
> u64 dpa);
> +int cxl_region_nid(struct cxl_region *cxlr);
>
> #else
> +static inline int cxl_region_nid(struct cxl_region *cxlr)
> +{
> + return NUMA_NO_NODE;
> +}
> static inline u64 cxl_dpa_to_hpa(struct cxl_region *cxlr,
> const struct cxl_memdev *cxlmd, u64 dpa)
> {
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index 548564c770c0..d7999260f004 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -856,6 +856,28 @@ int cxl_enumerate_cmds(struct cxl_memdev_state *mds)
> }
> EXPORT_SYMBOL_NS_GPL(cxl_enumerate_cmds, "CXL");
>
> +static u64 cxlr_hpa_cache_alias(struct cxl_region *cxlr, u64 hpa)
> +{
> + struct cxl_region_params *p;
> + int nid;
> +
> + if (!cxlr)
> + return ~0ULL;
> +
> + p = &cxlr->params;
> + if (!p->cache_size)
> + return ~0ULL;
> +
> + nid = cxl_region_nid(cxlr);
> + if (nid == NUMA_NO_NODE)
> + nid = 0;

Just noticed that this chunk and the related function can be dropped. Not used.

DJ

> +
> + if (hpa >= p->res->start + p->cache_size)
> + return hpa - p->cache_size;
> +
> + return hpa + p->cache_size;
> +}
> +
> void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
> enum cxl_event_log_type type,
> enum cxl_event_type event_type,
> @@ -871,7 +893,7 @@ void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
> }
>
> if (trace_cxl_general_media_enabled() || trace_cxl_dram_enabled()) {
> - u64 dpa, hpa = ULLONG_MAX;
> + u64 dpa, hpa = ULLONG_MAX, hpa_alias = 0;
> struct cxl_region *cxlr;
>
> /*
> @@ -884,14 +906,17 @@ void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
>
> dpa = le64_to_cpu(evt->media_hdr.phys_addr) & CXL_DPA_MASK;
> cxlr = cxl_dpa_to_region(cxlmd, dpa);
> - if (cxlr)
> + if (cxlr) {
> hpa = cxl_dpa_to_hpa(cxlr, cxlmd, dpa);
> + hpa_alias = cxlr_hpa_cache_alias(cxlr, hpa);
> + }
>
> if (event_type == CXL_CPER_EVENT_GEN_MEDIA)
> trace_cxl_general_media(cxlmd, type, cxlr, hpa,
> - &evt->gen_media);
> + hpa_alias, &evt->gen_media);
> else if (event_type == CXL_CPER_EVENT_DRAM)
> - trace_cxl_dram(cxlmd, type, cxlr, hpa, &evt->dram);
> + trace_cxl_dram(cxlmd, type, cxlr, hpa, hpa_alias,
> + &evt->dram);
> }
> }
> EXPORT_SYMBOL_NS_GPL(cxl_event_trace_record, "CXL");
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 2d8699a86b24..5d23bd26d9ba 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -2417,6 +2417,18 @@ static bool cxl_region_update_coordinates(struct cxl_region *cxlr, int nid)
> return true;
> }
>
> +int cxl_region_nid(struct cxl_region *cxlr)
> +{
> + struct cxl_region_params *p = &cxlr->params;
> + struct resource *res;
> +
> + guard(rwsem_read)(&cxl_region_rwsem);
> + res = p->res;
> + if (!res)
> + return NUMA_NO_NODE;
> + return phys_to_target_node(res->start);
> +}
> +
> static int cxl_region_perf_attrs_callback(struct notifier_block *nb,
> unsigned long action, void *arg)
> {
> diff --git a/drivers/cxl/core/trace.h b/drivers/cxl/core/trace.h
> index 8389a94adb1a..257f60f16e4c 100644
> --- a/drivers/cxl/core/trace.h
> +++ b/drivers/cxl/core/trace.h
> @@ -316,9 +316,10 @@ TRACE_EVENT(cxl_generic_event,
> TRACE_EVENT(cxl_general_media,
>
> TP_PROTO(const struct cxl_memdev *cxlmd, enum cxl_event_log_type log,
> - struct cxl_region *cxlr, u64 hpa, struct cxl_event_gen_media *rec),
> + struct cxl_region *cxlr, u64 hpa, u64 hpa_alias,
> + struct cxl_event_gen_media *rec),
>
> - TP_ARGS(cxlmd, log, cxlr, hpa, rec),
> + TP_ARGS(cxlmd, log, cxlr, hpa, hpa_alias, rec),
>
> TP_STRUCT__entry(
> CXL_EVT_TP_entry
> @@ -332,6 +333,7 @@ TRACE_EVENT(cxl_general_media,
> __array(u8, comp_id, CXL_EVENT_GEN_MED_COMP_ID_SIZE)
> /* Following are out of order to pack trace record */
> __field(u64, hpa)
> + __field(u64, hpa_alias)
> __field_struct(uuid_t, region_uuid)
> __field(u16, validity_flags)
> __field(u8, rank)
> @@ -358,6 +360,7 @@ TRACE_EVENT(cxl_general_media,
> CXL_EVENT_GEN_MED_COMP_ID_SIZE);
> __entry->validity_flags = get_unaligned_le16(&rec->media_hdr.validity_flags);
> __entry->hpa = hpa;
> + __entry->hpa_alias = hpa_alias;
> if (cxlr) {
> __assign_str(region_name);
> uuid_copy(&__entry->region_uuid, &cxlr->params.uuid);
> @@ -370,7 +373,7 @@ TRACE_EVENT(cxl_general_media,
> CXL_EVT_TP_printk("dpa=%llx dpa_flags='%s' " \
> "descriptor='%s' type='%s' transaction_type='%s' channel=%u rank=%u " \
> "device=%x comp_id=%s validity_flags='%s' " \
> - "hpa=%llx region=%s region_uuid=%pUb",
> + "hpa=%llx hpa_alias0=%llx region=%s region_uuid=%pUb",
> __entry->dpa, show_dpa_flags(__entry->dpa_flags),
> show_event_desc_flags(__entry->descriptor),
> show_gmer_mem_event_type(__entry->type),
> @@ -378,7 +381,8 @@ TRACE_EVENT(cxl_general_media,
> __entry->channel, __entry->rank, __entry->device,
> __print_hex(__entry->comp_id, CXL_EVENT_GEN_MED_COMP_ID_SIZE),
> show_valid_flags(__entry->validity_flags),
> - __entry->hpa, __get_str(region_name), &__entry->region_uuid
> + __entry->hpa, __entry->hpa_alias, __get_str(region_name),
> + &__entry->region_uuid
> )
> );
>
> @@ -424,9 +428,10 @@ TRACE_EVENT(cxl_general_media,
> TRACE_EVENT(cxl_dram,
>
> TP_PROTO(const struct cxl_memdev *cxlmd, enum cxl_event_log_type log,
> - struct cxl_region *cxlr, u64 hpa, struct cxl_event_dram *rec),
> + struct cxl_region *cxlr, u64 hpa, u64 hpa_alias,
> + struct cxl_event_dram *rec),
>
> - TP_ARGS(cxlmd, log, cxlr, hpa, rec),
> + TP_ARGS(cxlmd, log, cxlr, hpa, hpa_alias, rec),
>
> TP_STRUCT__entry(
> CXL_EVT_TP_entry
> @@ -442,6 +447,7 @@ TRACE_EVENT(cxl_dram,
> __field(u32, row)
> __array(u8, cor_mask, CXL_EVENT_DER_CORRECTION_MASK_SIZE)
> __field(u64, hpa)
> + __field(u64, hpa_alias)
> __field_struct(uuid_t, region_uuid)
> __field(u8, rank) /* Out of order to pack trace record */
> __field(u8, bank_group) /* Out of order to pack trace record */
> @@ -472,6 +478,7 @@ TRACE_EVENT(cxl_dram,
> memcpy(__entry->cor_mask, &rec->correction_mask,
> CXL_EVENT_DER_CORRECTION_MASK_SIZE);
> __entry->hpa = hpa;
> + __entry->hpa_alias = hpa_alias;
> if (cxlr) {
> __assign_str(region_name);
> uuid_copy(&__entry->region_uuid, &cxlr->params.uuid);
> @@ -485,7 +492,7 @@ TRACE_EVENT(cxl_dram,
> "transaction_type='%s' channel=%u rank=%u nibble_mask=%x " \
> "bank_group=%u bank=%u row=%u column=%u cor_mask=%s " \
> "validity_flags='%s' " \
> - "hpa=%llx region=%s region_uuid=%pUb",
> + "hpa=%llx hpa_alias0=%llx region=%s region_uuid=%pUb",
> __entry->dpa, show_dpa_flags(__entry->dpa_flags),
> show_event_desc_flags(__entry->descriptor),
> show_dram_mem_event_type(__entry->type),
> @@ -495,7 +502,8 @@ TRACE_EVENT(cxl_dram,
> __entry->row, __entry->column,
> __print_hex(__entry->cor_mask, CXL_EVENT_DER_CORRECTION_MASK_SIZE),
> show_dram_valid_flags(__entry->validity_flags),
> - __entry->hpa, __get_str(region_name), &__entry->region_uuid
> + __entry->hpa_alias, __entry->hpa, __get_str(region_name),
> + &__entry->region_uuid
> )
> );
>