UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

cxl/region: Move coherence tracking into cxl_region_attach() 

Each time the contents of a given HPA are potentially changed in a cache
incoherent manner the CXL core sets CXL_REGION_F_INCOHERENT to
invalidate CPU caches before the region is used.

Successful invocation of attach_target() indicates that DPA has been
newly assigned to a given HPA in the dynamic region creation flow.
However, attach_target() is also reused in the autodiscovery flow where
the region was activated by platform firmware. In that case there is no
need to invalidate caches because that region is already in active use
and nothing about the autodiscovery flow modifies the HPA-to-DPA
relationship.

In the autodiscovery case cxl_region_attach() exits early after
determining the endpoint decoder is already correctly attached to the
region.

Fixes: a32320b71f ("cxl/region: Add region autodiscovery")
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168002858817.50647.1217607907088920888.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dan Williams 2023-04-03 15:01:20 -07:00
parent 030f880342
commit 9ff3eec958
1 changed files with 1 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/cxl/core/region.c
View File

@ -1674,6 +1674,7 @@ static int cxl_region_attach(struct cxl_region *cxlr,
if (rc)
goto err_decrement;
p->state = CXL_CONFIG_ACTIVE;
set_bit(CXL_REGION_F_INCOHERENT, &cxlr->flags);
}
cxled->cxld.interleave_ways = p->interleave_ways;
@ -1775,8 +1776,6 @@ static int attach_target(struct cxl_region *cxlr,
down_read(&cxl_dpa_rwsem);
rc = cxl_region_attach(cxlr, cxled, pos);
if (rc == 0)
set_bit(CXL_REGION_F_INCOHERENT, &cxlr->flags);
up_read(&cxl_dpa_rwsem);
up_write(&cxl_region_rwsem);
return rc;