Fabio M. De Francesco wrote:
> cxl_event_common was a poor naming choice and caused confusion with the
> existing Common Event Record.
I would say "unfortunate" rather than "poor".
> Use cxl_event_media as a common structure to record information about DRAM
> and General Media events because it simplifies handling the two events.
>
> Suggested-by: Dan Williams <dan.j.williams@intel.com>
> Fixes: 6aec00139d3a ("cxl/core: Add region info to cxl_general_media and cxl_dram events")
What is the fix? There is no user visible behavior changes that results from
this cleanup, right?
> Signed-off-by: Fabio M. De Francesco <fabio.m.de.francesco@linux.intel.com>
> ---
>
> Changes for v2:
> - Extend the commit message (Alison);
> - Add a "Fixes" tag (Alison, thanks).
>
> drivers/cxl/core/mbox.c | 6 ++--
> drivers/cxl/core/trace.h | 4 +--
> include/linux/cxl-event.h | 70 +++++++++++++++---------------------
> tools/testing/cxl/test/mem.c | 4 +--
> 4 files changed, 36 insertions(+), 48 deletions(-)
Oh, nice, net reduction in code I was not expecting.
>
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index 2626f3fff201..ad4d7b0f7f4d 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -875,16 +875,16 @@ void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
> guard(rwsem_read)(&cxl_region_rwsem);
> guard(rwsem_read)(&cxl_dpa_rwsem);
>
> - dpa = le64_to_cpu(evt->common.phys_addr) & CXL_DPA_MASK;
> + dpa = le64_to_cpu(evt->media_common.phys_addr) & CXL_DPA_MASK;
I was hoping at the end of this to get rid of the word "common" to avoid any
more "common event record confusion".
> cxlr = cxl_dpa_to_region(cxlmd, dpa);
> if (cxlr)
> hpa = cxl_trace_hpa(cxlr, cxlmd, dpa);
>
> if (event_type == CXL_CPER_EVENT_GEN_MEDIA)
> trace_cxl_general_media(cxlmd, type, cxlr, hpa,
> - &evt->gen_media);
> + &evt->media_general);
> else if (event_type == CXL_CPER_EVENT_DRAM)
> - trace_cxl_dram(cxlmd, type, cxlr, hpa, &evt->dram);
> + trace_cxl_dram(cxlmd, type, cxlr, hpa, &evt->media_dram);
> }
> }
> EXPORT_SYMBOL_NS_GPL(cxl_event_trace_record, CXL);
> diff --git a/drivers/cxl/core/trace.h b/drivers/cxl/core/trace.h
> index 07a0394b1d99..2c7293761bb2 100644
> --- a/drivers/cxl/core/trace.h
> +++ b/drivers/cxl/core/trace.h
> @@ -316,7 +316,7 @@ 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, struct cxl_event_media *rec),
>
> TP_ARGS(cxlmd, log, cxlr, hpa, rec),
>
> @@ -413,7 +413,7 @@ 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, struct cxl_event_media *rec),
>
> TP_ARGS(cxlmd, log, cxlr, hpa, rec),
>
> diff --git a/include/linux/cxl-event.h b/include/linux/cxl-event.h
> index 60b25020281f..e417556cc120 100644
> --- a/include/linux/cxl-event.h
> +++ b/include/linux/cxl-event.h
> @@ -32,41 +32,38 @@ struct cxl_event_generic {
> * CXL rev 3.0 Section 8.2.9.2.1.1; Table 8-43
> */
> #define CXL_EVENT_GEN_MED_COMP_ID_SIZE 0x10
> -struct cxl_event_gen_media {
> - struct cxl_event_record_hdr hdr;
> - __le64 phys_addr;
> - u8 descriptor;
> - u8 type;
> - u8 transaction_type;
> - u8 validity_flags[2];
> - u8 channel;
> - u8 rank;
> - u8 device[3];
> - u8 component_id[CXL_EVENT_GEN_MED_COMP_ID_SIZE];
> - u8 reserved[46];
> -} __packed;
> -
> /*
> * DRAM Event Record - DER
> * CXL rev 3.0 section 8.2.9.2.1.2; Table 3-44
> */
> #define CXL_EVENT_DER_CORRECTION_MASK_SIZE 0x20
> -struct cxl_event_dram {
> +struct cxl_event_media {
> struct cxl_event_record_hdr hdr;
> - __le64 phys_addr;
> - u8 descriptor;
> - u8 type;
> - u8 transaction_type;
> - u8 validity_flags[2];
> - u8 channel;
> - u8 rank;
> - u8 nibble_mask[3];
> - u8 bank_group;
> - u8 bank;
> - u8 row[3];
> - u8 column[2];
> - u8 correction_mask[CXL_EVENT_DER_CORRECTION_MASK_SIZE];
> - u8 reserved[0x17];
> + struct_group_tagged(cxl_event_media_hdr, media_hdr,
> + __le64 phys_addr;
> + u8 descriptor;
> + u8 type;
> + u8 transaction_type;
> + u8 validity_flags[2];
> + u8 channel;
> + u8 rank;
> + );
Oh nice you went for the full 'struct_group_tagged' proposal. However, given
that Jonathan is already asking questions about "__packed", lets do the simpler
change, something like this, what do you think? This also preserves type-safety.
diff --git a/include/linux/cxl-event.h b/include/linux/cxl-event.h
index 60b25020281f..f48b59943977 100644
--- a/include/linux/cxl-event.h
+++ b/include/linux/cxl-event.h
@@ -33,14 +33,16 @@ struct cxl_event_generic {
*/
#define CXL_EVENT_GEN_MED_COMP_ID_SIZE 0x10
struct cxl_event_gen_media {
- struct cxl_event_record_hdr hdr;
- __le64 phys_addr;
- u8 descriptor;
- u8 type;
- u8 transaction_type;
- u8 validity_flags[2];
- u8 channel;
- u8 rank;
+ struct cxl_event_media_hdr {
+ struct cxl_event_record_hdr hdr;
+ __le64 phys_addr;
+ u8 descriptor;
+ u8 type;
+ u8 transaction_type;
+ u8 validity_flags[2];
+ u8 channel;
+ u8 rank;
+ } hdr;
u8 device[3];
u8 component_id[CXL_EVENT_GEN_MED_COMP_ID_SIZE];
u8 reserved[46];
@@ -52,14 +54,7 @@ struct cxl_event_gen_media {
*/
#define CXL_EVENT_DER_CORRECTION_MASK_SIZE 0x20
struct cxl_event_dram {
- struct cxl_event_record_hdr hdr;
- __le64 phys_addr;
- u8 descriptor;
- u8 type;
- u8 transaction_type;
- u8 validity_flags[2];
- u8 channel;
- u8 rank;
+ struct cxl_event_media_hdr hdr;
u8 nibble_mask[3];
u8 bank_group;
u8 bank;
@@ -109,7 +104,7 @@ union cxl_event {
struct cxl_event_gen_media gen_media;
struct cxl_event_dram dram;
struct cxl_event_mem_module mem_module;
- struct cxl_event_common common;
+ struct cxl_event_media_hdr media_hdr;
} __packed;
/*On Friday, May 17, 2024 2:43:33 AM GMT+2 Dan Williams wrote:
> Fabio M. De Francesco wrote:
> > cxl_event_common was a poor naming choice and caused confusion with the
> > existing Common Event Record.
>
> I would say "unfortunate" rather than "poor".
>
Agreed.
> > Use cxl_event_media as a common structure to record information about DRAM
> > and General Media events because it simplifies handling the two events.
> >
> > Suggested-by: Dan Williams <dan.j.williams@intel.com>
> > Fixes: 6aec00139d3a ("cxl/core: Add region info to cxl_general_media and
> > cxl_dram events")
> What is the fix? There is no user visible behavior changes that results from
> this cleanup, right?
Right.
> > Signed-off-by: Fabio M. De Francesco
> > <fabio.m.de.francesco@linux.intel.com>
> > ---
> >
> > Changes for v2:
> > - Extend the commit message (Alison);
> > - Add a "Fixes" tag (Alison, thanks).
> >
> > drivers/cxl/core/mbox.c | 6 ++--
> > drivers/cxl/core/trace.h | 4 +--
> > include/linux/cxl-event.h | 70 +++++++++++++++---------------------
> > tools/testing/cxl/test/mem.c | 4 +--
> > 4 files changed, 36 insertions(+), 48 deletions(-)
>
> Oh, nice, net reduction in code I was not expecting.
>
> > diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> > index 2626f3fff201..ad4d7b0f7f4d 100644
> > --- a/drivers/cxl/core/mbox.c
> > +++ b/drivers/cxl/core/mbox.c
> > @@ -875,16 +875,16 @@ void cxl_event_trace_record(const struct cxl_memdev
> > *cxlmd,>
> > guard(rwsem_read)(&cxl_region_rwsem);
> > guard(rwsem_read)(&cxl_dpa_rwsem);
> >
> > - dpa = le64_to_cpu(evt->common.phys_addr) &
CXL_DPA_MASK;
> > + dpa = le64_to_cpu(evt->media_common.phys_addr) &
CXL_DPA_MASK;
>
> I was hoping at the end of this to get rid of the word "common" to avoid any
> more "common event record confusion".
Right, still an unfortunate naming choice.
> > [...]
>
> Oh nice you went for the full 'struct_group_tagged' proposal. However, given
> that Jonathan is already asking questions about "__packed", lets do the
> simpler change, something like this, what do you think?
I think that these simpler changes are better.
> This also preserves
> type-safety.
>
> diff --git a/include/linux/cxl-event.h b/include/linux/cxl-event.h
> index 60b25020281f..f48b59943977 100644
> --- a/include/linux/cxl-event.h
> +++ b/include/linux/cxl-event.h
> @@ -33,14 +33,16 @@ struct cxl_event_generic {
> */
> #define CXL_EVENT_GEN_MED_COMP_ID_SIZE 0x10
> struct cxl_event_gen_media {
> - struct cxl_event_record_hdr hdr;
> - __le64 phys_addr;
> - u8 descriptor;
> - u8 type;
> - u8 transaction_type;
> - u8 validity_flags[2];
> - u8 channel;
> - u8 rank;
> + struct cxl_event_media_hdr {
> + struct cxl_event_record_hdr hdr;
> + __le64 phys_addr;
> + u8 descriptor;
> + u8 type;
> + u8 transaction_type;
> + u8 validity_flags[2];
> + u8 channel;
> + u8 rank;
> + } hdr;
> u8 device[3];
> u8 component_id[CXL_EVENT_GEN_MED_COMP_ID_SIZE];
> u8 reserved[46];
> @@ -52,14 +54,7 @@ struct cxl_event_gen_media {
> */
> #define CXL_EVENT_DER_CORRECTION_MASK_SIZE 0x20
> struct cxl_event_dram {
> - struct cxl_event_record_hdr hdr;
> - __le64 phys_addr;
> - u8 descriptor;
> - u8 type;
> - u8 transaction_type;
> - u8 validity_flags[2];
> - u8 channel;
> - u8 rank;
> + struct cxl_event_media_hdr hdr;
> u8 nibble_mask[3];
> u8 bank_group;
> u8 bank;
> @@ -109,7 +104,7 @@ union cxl_event {
> struct cxl_event_gen_media gen_media;
> struct cxl_event_dram dram;
> struct cxl_event_mem_module mem_module;
> - struct cxl_event_common common;
> + struct cxl_event_media_hdr media_hdr;
> } __packed;
>
> /*
I'll make v3 according to the suggestion showed above.
Thanks,
Fabio
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