On Mon, Feb 24, 2025 at 11:21:01AM -0700, Dave Jiang wrote:
> Add the aliased address of extended linear cache when emitting event
> trace for DRAM and general media of CXL events.
What about cxl_poison trace events?
When cxl device poison lists are read, or poison is injected
or cleared, an HPA is included in the trace event. Seems the
hpa_alias0 belong there too.
>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> ---
> v4:
> - Make error using ULLONG_MAX consistently. (Alison)
> - Make hpa_alias0 naming consistent. (Alison)
> - Swap incorrect position of hpa and hpa_alias0. (Alison)
> ---
> drivers/cxl/core/mbox.c | 28 ++++++++++++++++++++++++----
> drivers/cxl/core/trace.h | 22 ++++++++++++++--------
> 2 files changed, 38 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index 548564c770c0..808b6a3c577b 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -856,6 +856,23 @@ 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;
> +
> + if (!cxlr)
> + return ULLONG_MAX;
checked cxlr in caller
> +
> + p = &cxlr->params;
> + if (!p->cache_size)
> + return ULLONG_MAX;
> +
> + if (hpa >= p->res->start + p->cache_size)
> + return hpa - p->cache_size;
> +
> + return hpa + p->cache_size;
Since a DPA can only be in the cxl resource half of the p->res, not in
the extended cache, is alias always hpa - cache.
> void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
> enum cxl_event_log_type type,
> enum cxl_event_type event_type,
> @@ -871,7 +888,7 @@ 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 = ULLONG_MAX;
> struct cxl_region *cxlr;
>
> /*
> @@ -884,14 +901,17 @@ 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);
> + }
>
How about something like this to eliminate cxlr_hpa_cache_alias():
if (trace_cxl_general_media_enabled() || trace_cxl_dram_enabled()) {
- u64 dpa, hpa = ULLONG_MAX, hpa_alias = ULLONG_MAX;
+ u64 dpa, cache_size, hpa = ULLONG_MAX, hpa_alias = ULLONG_MAX;
struct cxl_region *cxlr;
/*
@@ -904,7 +887,9 @@ void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
cxlr = cxl_dpa_to_region(cxlmd, dpa);
if (cxlr) {
hpa = cxl_dpa_to_hpa(cxlr, cxlmd, dpa);
- hpa_alias = cxlr_hpa_cache_alias(cxlr, hpa);
+ cache_size = cxlr->params.cache_size;
+ if (cache_size)
+ hpa_alias = hpa - cache_size;
}
snip
