cxl/region: Drop goto pattern of construct_region()

Some operations need to be protected by the cxl_region_rwsem in
construct_region(). Currently, construct_region() uses down_write() and
up_write() for the cxl_region_rwsem locking, so there is a goto pattern
after down_write() invoked to release cxl_region_rwsem.

construct region() can be optimized to remove the goto pattern. The
changes are creating a new function called __construct_region() which
will include all checking and operations protected by the
cxl_region_rwsem, and using guard(rwsem_write) to replace down_write()
and up_write() in __construct_region().

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Li Ming <ming.li@zohomail.com>
Link: https://patch.msgid.link/20250221013205.126419-1-ming.li@zohomail.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
pull/1193/head
Li Ming 2025-02-21 09:32:05 +08:00 committed by Dave Jiang
parent 9e7b7ab5af
commit 5ec67596e3
1 changed files with 39 additions and 32 deletions

View File

@ -3216,49 +3216,31 @@ static int match_region_by_range(struct device *dev, const void *data)
return 0;
}
/* Establish an empty region covering the given HPA range */
static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd,
struct cxl_endpoint_decoder *cxled)
static int __construct_region(struct cxl_region *cxlr,
struct cxl_root_decoder *cxlrd,
struct cxl_endpoint_decoder *cxled)
{
struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
struct cxl_port *port = cxlrd_to_port(cxlrd);
struct range *hpa = &cxled->cxld.hpa_range;
struct cxl_region_params *p;
struct cxl_region *cxlr;
struct resource *res;
int rc;
do {
cxlr = __create_region(cxlrd, cxled->mode,
atomic_read(&cxlrd->region_id));
} while (IS_ERR(cxlr) && PTR_ERR(cxlr) == -EBUSY);
if (IS_ERR(cxlr)) {
dev_err(cxlmd->dev.parent,
"%s:%s: %s failed assign region: %ld\n",
dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
__func__, PTR_ERR(cxlr));
return cxlr;
}
down_write(&cxl_region_rwsem);
guard(rwsem_write)(&cxl_region_rwsem);
p = &cxlr->params;
if (p->state >= CXL_CONFIG_INTERLEAVE_ACTIVE) {
dev_err(cxlmd->dev.parent,
"%s:%s: %s autodiscovery interrupted\n",
dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
__func__);
rc = -EBUSY;
goto err;
return -EBUSY;
}
set_bit(CXL_REGION_F_AUTO, &cxlr->flags);
res = kmalloc(sizeof(*res), GFP_KERNEL);
if (!res) {
rc = -ENOMEM;
goto err;
}
if (!res)
return -ENOMEM;
*res = DEFINE_RES_MEM_NAMED(hpa->start, range_len(hpa),
dev_name(&cxlr->dev));
@ -3281,7 +3263,7 @@ static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd,
rc = sysfs_update_group(&cxlr->dev.kobj, get_cxl_region_target_group());
if (rc)
goto err;
return rc;
dev_dbg(cxlmd->dev.parent, "%s:%s: %s %s res: %pr iw: %d ig: %d\n",
dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), __func__,
@ -3290,14 +3272,39 @@ static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd,
/* ...to match put_device() in cxl_add_to_region() */
get_device(&cxlr->dev);
up_write(&cxl_region_rwsem);
return 0;
}
/* Establish an empty region covering the given HPA range */
static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd,
struct cxl_endpoint_decoder *cxled)
{
struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
struct cxl_port *port = cxlrd_to_port(cxlrd);
struct cxl_region *cxlr;
int rc;
do {
cxlr = __create_region(cxlrd, cxled->mode,
atomic_read(&cxlrd->region_id));
} while (IS_ERR(cxlr) && PTR_ERR(cxlr) == -EBUSY);
if (IS_ERR(cxlr)) {
dev_err(cxlmd->dev.parent,
"%s:%s: %s failed assign region: %ld\n",
dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
__func__, PTR_ERR(cxlr));
return cxlr;
}
rc = __construct_region(cxlr, cxlrd, cxled);
if (rc) {
devm_release_action(port->uport_dev, unregister_region, cxlr);
return ERR_PTR(rc);
}
return cxlr;
err:
up_write(&cxl_region_rwsem);
devm_release_action(port->uport_dev, unregister_region, cxlr);
return ERR_PTR(rc);
}
int cxl_add_to_region(struct cxl_port *root, struct cxl_endpoint_decoder *cxled)