Allocate and initialize struct ice_adapter object only once per physical
card instead of once per port. This is not a big deal by now, but we want
to extend this struct more and more in the near future. Our plans include
PTP stuff and a devlink instance representing whole-device/physical card.
Transactions requiring to be sleep-able (like those doing user (here ice)
memory allocation) must be performed with an additional (on top of xarray)
mutex. Adding it here removes need to xa_lock() manually.
Since this commit is a reimplementation of ice_adapter_get(), a rather new
scoped_guard() wrapper for locking is used to simplify the logic.
It's worth to mention that xa_insert() use gives us both slot reservation
and checks if it is already filled, what simplifies code a tiny bit.
Reviewed-by: Wojciech Drewek <wojciech.dre...@intel.com>
Signed-off-by: Przemek Kitszel <przemyslaw.kits...@intel.com>
---
drivers/net/ethernet/intel/ice/ice_adapter.c | 60 +++++++++-----------
1 file changed, 28 insertions(+), 32 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_adapter.c
b/drivers/net/ethernet/intel/ice/ice_adapter.c
index 52d15ef7f4b1..ad84d8ad49a6 100644
--- a/drivers/net/ethernet/intel/ice/ice_adapter.c
+++ b/drivers/net/ethernet/intel/ice/ice_adapter.c
@@ -11,6 +11,7 @@
#include "ice_adapter.h"
static DEFINE_XARRAY(ice_adapters);
+static DEFINE_MUTEX(ice_adapters_mutex);
/* PCI bus number is 8 bits. Slot is 5 bits. Domain can have the rest. */
#define INDEX_FIELD_DOMAIN GENMASK(BITS_PER_LONG - 1, 13)
@@ -47,8 +48,6 @@ static void ice_adapter_free(struct ice_adapter *adapter)
kfree(adapter);
}
-DEFINE_FREE(ice_adapter_free, struct ice_adapter*, if (_T)
ice_adapter_free(_T))
-
/**
* ice_adapter_get - Get a shared ice_adapter structure.
* @pdev: Pointer to the pci_dev whose driver is getting the ice_adapter.
@@ -64,53 +63,50 @@ DEFINE_FREE(ice_adapter_free, struct ice_adapter*, if (_T)
ice_adapter_free(_T))
*/
struct ice_adapter *ice_adapter_get(const struct pci_dev *pdev)
{
- struct ice_adapter *ret, __free(ice_adapter_free) *adapter = NULL;
unsigned long index = ice_adapter_index(pdev);
-
- adapter = ice_adapter_new();
- if (!adapter)
- return ERR_PTR(-ENOMEM);
-
- xa_lock(&ice_adapters);
- ret = __xa_cmpxchg(&ice_adapters, index, NULL, adapter, GFP_KERNEL);
- if (xa_is_err(ret)) {
- ret = ERR_PTR(xa_err(ret));
- goto unlock;
- }
- if (ret) {
- refcount_inc(&ret->refcount);
- goto unlock;
+ struct ice_adapter *adapter;
+ int err;
+
+ scoped_guard(mutex, &ice_adapters_mutex) {
+ err = xa_insert(&ice_adapters, index, NULL, GFP_KERNEL);
+ if (err == -EBUSY) {
+ adapter = xa_load(&ice_adapters, index);
+ refcount_inc(&adapter->refcount);
+ return adapter;
+ }
+ if (err)
+ return ERR_PTR(err);
+
+ adapter = ice_adapter_new();
+ if (!adapter)
+ return ERR_PTR(-ENOMEM);
+ xa_store(&ice_adapters, index, adapter, GFP_KERNEL);
}
- ret = no_free_ptr(adapter);
-unlock:
- xa_unlock(&ice_adapters);
- return ret;
+ return adapter;
}
/**
* ice_adapter_put - Release a reference to the shared ice_adapter structure.
* @pdev: Pointer to the pci_dev whose driver is releasing the ice_adapter.
*
* Releases the reference to ice_adapter previously obtained with
* ice_adapter_get.
*
- * Context: Any.
+ * Context: Process, may sleep.
*/
void ice_adapter_put(const struct pci_dev *pdev)
{
unsigned long index = ice_adapter_index(pdev);
struct ice_adapter *adapter;
- xa_lock(&ice_adapters);
- adapter = xa_load(&ice_adapters, index);
- if (WARN_ON(!adapter))
- goto unlock;
+ scoped_guard(mutex, &ice_adapters_mutex) {
+ adapter = xa_load(&ice_adapters, index);
+ if (WARN_ON(!adapter))
+ return;
+ if (!refcount_dec_and_test(&adapter->refcount))
+ return;
- if (!refcount_dec_and_test(&adapter->refcount))
- goto unlock;
-
- WARN_ON(__xa_erase(&ice_adapters, index) != adapter);
+ WARN_ON(xa_erase(&ice_adapters, index) != adapter);
+ }
ice_adapter_free(adapter);
-unlock:
- xa_unlock(&ice_adapters);
}
base-commit: 37cf9b0b18612fcb52a819518074e4a0beabe29a
--
2.39.3
