Re: [PATCH 2/2] cxl/trace: Remove unnecessary memcpy's

From: Dave Jiang
Date: Thu Feb 01 2024 - 11:23:36 EST




On 1/31/24 16:55, Ira Weiny wrote:
> CPER events don't have UUIDs. Therefore UUIDs were removed from the
> records passed to trace events and replaced with hard coded values.
>
> As pointed out by Jonathan, the new defines for the UUIDs present a more
> efficient way to assign UUID in trace records.[1]
>
> Replace memcpy's with the use of static data.
>
> [1] https://lore.kernel.org/all/20240108132325.00000e9c@xxxxxxxxxx/
>
> Suggested-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>

Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> ---
> drivers/cxl/core/trace.h | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/cxl/core/trace.h b/drivers/cxl/core/trace.h
> index 89445435303a..bdf117a33744 100644
> --- a/drivers/cxl/core/trace.h
> +++ b/drivers/cxl/core/trace.h
> @@ -338,7 +338,7 @@ TRACE_EVENT(cxl_general_media,
>
> TP_fast_assign(
> CXL_EVT_TP_fast_assign(cxlmd, log, rec->hdr);
> - memcpy(&__entry->hdr_uuid, &CXL_EVENT_GEN_MEDIA_UUID, sizeof(uuid_t));
> + __entry->hdr_uuid = CXL_EVENT_GEN_MEDIA_UUID;
>
> /* General Media */
> __entry->dpa = le64_to_cpu(rec->phys_addr);
> @@ -425,7 +425,7 @@ TRACE_EVENT(cxl_dram,
>
> TP_fast_assign(
> CXL_EVT_TP_fast_assign(cxlmd, log, rec->hdr);
> - memcpy(&__entry->hdr_uuid, &CXL_EVENT_DRAM_UUID, sizeof(uuid_t));
> + __entry->hdr_uuid = CXL_EVENT_DRAM_UUID;
>
> /* DRAM */
> __entry->dpa = le64_to_cpu(rec->phys_addr);
> @@ -573,7 +573,7 @@ TRACE_EVENT(cxl_memory_module,
>
> TP_fast_assign(
> CXL_EVT_TP_fast_assign(cxlmd, log, rec->hdr);
> - memcpy(&__entry->hdr_uuid, &CXL_EVENT_MEM_MODULE_UUID, sizeof(uuid_t));
> + __entry->hdr_uuid = CXL_EVENT_MEM_MODULE_UUID;
>
> /* Memory Module Event */
> __entry->event_type = rec->event_type;
>