From: Ankit Agrawal <ankita@xxxxxxxxxx>
Grace Blackwell systems could have multiple GPUs on a socket and
thus are associated with the corresponding EGM region for that
socket. Track the GPUs as a list.
On the device probe, the device pci_dev struct is added to a
linked list of the appropriate EGM region.
Similarly on device remove, the pci_dev struct for the GPU
is removed from the EGM region.
Since the GPUs on a socket have the same EGM region, they have
the have the same set of EGM region information. Skip the EGM
region information fetch if already done through a differnt
GPU on the same socket.
Signed-off-by: Ankit Agrawal <ankita@xxxxxxxxxx>
---
drivers/vfio/pci/nvgrace-gpu/egm_dev.c | 29 ++++++++++++++++++++++
drivers/vfio/pci/nvgrace-gpu/egm_dev.h | 4 +++
drivers/vfio/pci/nvgrace-gpu/main.c | 34 +++++++++++++++++++++++---
include/linux/nvgrace-egm.h | 6 +++++
4 files changed, 70 insertions(+), 3 deletions(-)
diff --git a/drivers/vfio/pci/nvgrace-gpu/egm_dev.c b/drivers/vfio/pci/nvgrace-gpu/egm_dev.c
index f4e27dadf1ef..28cfd29eda56 100644
--- a/drivers/vfio/pci/nvgrace-gpu/egm_dev.c
+++ b/drivers/vfio/pci/nvgrace-gpu/egm_dev.c
@@ -17,6 +17,33 @@ int nvgrace_gpu_has_egm_property(struct pci_dev *pdev, u64 *pegmpxm)
pegmpxm);
}
+int add_gpu(struct nvgrace_egm_dev *egm_dev, struct pci_dev *pdev)
+{
+ struct gpu_node *node;
+
+ node = kvzalloc(sizeof(*node), GFP_KERNEL);
+ if (!node)
+ return -ENOMEM;
+
+ node->pdev = pdev;
+
+ list_add_tail(&node->list, &egm_dev->gpus);
+
+ return 0;
+}
+
+void remove_gpu(struct nvgrace_egm_dev *egm_dev, struct pci_dev *pdev)
+{
+ struct gpu_node *node, *tmp;
+
+ list_for_each_entry_safe(node, tmp, &egm_dev->gpus, list) {
+ if (node->pdev == pdev) {
+ list_del(&node->list);
+ kvfree(node);
+ }
+ }
+}
+
static void nvgrace_gpu_release_aux_device(struct device *device)
{
struct auxiliary_device *aux_dev = container_of(device, struct auxiliary_device, dev);
@@ -37,6 +64,8 @@ nvgrace_gpu_create_aux_device(struct pci_dev *pdev, const char *name,
goto create_err;
egm_dev->egmpxm = egmpxm;
+ INIT_LIST_HEAD(&egm_dev->gpus);
+
egm_dev->aux_dev.id = egmpxm;
egm_dev->aux_dev.name = name;
egm_dev->aux_dev.dev.release = nvgrace_gpu_release_aux_device;
diff --git a/drivers/vfio/pci/nvgrace-gpu/egm_dev.h b/drivers/vfio/pci/nvgrace-gpu/egm_dev.h
index c00f5288f4e7..1635753c9e50 100644
--- a/drivers/vfio/pci/nvgrace-gpu/egm_dev.h
+++ b/drivers/vfio/pci/nvgrace-gpu/egm_dev.h
@@ -10,6 +10,10 @@
int nvgrace_gpu_has_egm_property(struct pci_dev *pdev, u64 *pegmpxm);
+int add_gpu(struct nvgrace_egm_dev *egm_dev, struct pci_dev *pdev);
+
+void remove_gpu(struct nvgrace_egm_dev *egm_dev, struct pci_dev *pdev);
+
struct nvgrace_egm_dev *
nvgrace_gpu_create_aux_device(struct pci_dev *pdev, const char *name,
u64 egmphys);
diff --git a/drivers/vfio/pci/nvgrace-gpu/main.c b/drivers/vfio/pci/nvgrace-gpu/main.c
index 2cf851492990..436f0ac17332 100644
--- a/drivers/vfio/pci/nvgrace-gpu/main.c
+++ b/drivers/vfio/pci/nvgrace-gpu/main.c
@@ -66,9 +66,10 @@ static struct list_head egm_dev_list;
static int nvgrace_gpu_create_egm_aux_device(struct pci_dev *pdev)
{
- struct nvgrace_egm_dev_entry *egm_entry;
+ struct nvgrace_egm_dev_entry *egm_entry = NULL;
u64 egmpxm;
int ret = 0;
+ bool is_new_region = false;
/*
* EGM is an optional feature enabled in SBIOS. If disabled, there
@@ -79,6 +80,19 @@ static int nvgrace_gpu_create_egm_aux_device(struct pci_dev *pdev)
if (nvgrace_gpu_has_egm_property(pdev, &egmpxm))
goto exit;
+ list_for_each_entry(egm_entry, &egm_dev_list, list) {
+ /*
+ * A system could have multiple GPUs associated with an
+ * EGM region and will have the same set of EGM region
+ * information. Skip the EGM region information fetch if
+ * already done through a differnt GPU on the same socket.
+ */
+ if (egm_entry->egm_dev->egmpxm == egmpxm)
+ goto add_gpu;
+ }
+
+ is_new_region = true;
+
egm_entry = kvzalloc(sizeof(*egm_entry), GFP_KERNEL);
if (!egm_entry)
return -ENOMEM;
@@ -87,13 +101,23 @@ static int nvgrace_gpu_create_egm_aux_device(struct pci_dev *pdev)
nvgrace_gpu_create_aux_device(pdev, NVGRACE_EGM_DEV_NAME,
egmpxm);
if (!egm_entry->egm_dev) {
- kvfree(egm_entry);
ret = -EINVAL;
+ goto free_egm_entry;
+ }
+
+add_gpu:
+ ret = add_gpu(egm_entry->egm_dev, pdev);
+ if (!ret) {
+ if (is_new_region)
+ list_add_tail(&egm_entry->list, &egm_dev_list);
goto exit;
}
- list_add_tail(&egm_entry->list, &egm_dev_list);
+ if (is_new_region)
+ auxiliary_device_destroy(&egm_entry->egm_dev->aux_dev);
+free_egm_entry:
+ kvfree(egm_entry);
exit:
return ret;
}
@@ -112,6 +136,10 @@ static void nvgrace_gpu_destroy_egm_aux_device(struct pci_dev *pdev)
* device.
*/
if (egm_entry->egm_dev->egmpxm == egmpxm) {
+ remove_gpu(egm_entry->egm_dev, pdev);
+ if (!list_empty(&egm_entry->egm_dev->gpus))
+ break;
+
auxiliary_device_destroy(&egm_entry->egm_dev->aux_dev);
list_del(&egm_entry->list);
kvfree(egm_entry);
diff --git a/include/linux/nvgrace-egm.h b/include/linux/nvgrace-egm.h
index 9575d4ad4338..e42494a2b1a6 100644
--- a/include/linux/nvgrace-egm.h
+++ b/include/linux/nvgrace-egm.h
@@ -10,9 +10,15 @@
#define NVGRACE_EGM_DEV_NAME "egm"
+struct gpu_node {
+ struct list_head list;
+ struct pci_dev *pdev;
+};
+
struct nvgrace_egm_dev {
struct auxiliary_device aux_dev;
u64 egmpxm;
+ struct list_head gpus;
};
struct nvgrace_egm_dev_entry {
--
2.34.1
