On 8/14/25 3:29 PM, Lizhi Hou wrote:
> Walking hardware contexts created by a process is duplicated in multiple
> spots. Add a function, amdxdna_hwctx_walk(), and replace all spots.
>
> hwctx_srcu and dev_lock are good enough to protect hardware context list.
> Remove hwctx_lock.
>
> Signed-off-by: Lizhi Hou <lizhi....@amd.com>
> ---
> drivers/accel/amdxdna/aie2_ctx.c | 38 ++++++-----
> drivers/accel/amdxdna/aie2_message.c | 21 +++---
> drivers/accel/amdxdna/aie2_pci.c | 86 +++++++++++--------------
> drivers/accel/amdxdna/amdxdna_ctx.c | 26 ++++++--
> drivers/accel/amdxdna/amdxdna_ctx.h | 8 +--
> drivers/accel/amdxdna/amdxdna_pci_drv.c | 7 +-
> drivers/accel/amdxdna/amdxdna_pci_drv.h | 2 -
> 7 files changed, 97 insertions(+), 91 deletions(-)
>
> diff --git a/drivers/accel/amdxdna/aie2_ctx.c
> b/drivers/accel/amdxdna/aie2_ctx.c
> index 910ffb7051f4..b76877179b62 100644
> --- a/drivers/accel/amdxdna/aie2_ctx.c
> +++ b/drivers/accel/amdxdna/aie2_ctx.c
> @@ -133,11 +133,20 @@ static void aie2_hwctx_wait_for_idle(struct
> amdxdna_hwctx *hwctx)
> dma_fence_put(fence);
> }
>
> +static int aie2_hwctx_suspend_cb(struct amdxdna_hwctx *hwctx, void *arg)
> +{
> + struct amdxdna_dev *xdna = hwctx->client->xdna;
> +
> + aie2_hwctx_wait_for_idle(hwctx);
This is an existing problem; but shouldn't aie2_hwctx_wait_for_idle() be
looking at the return code for dma_fence_wait_timeout()?
Otherwise you can end up with a case that you put() the fence prematurely.
> + aie2_hwctx_stop(xdna, hwctx, NULL);
> + aie2_hwctx_status_shift_stop(hwctx);
> +
> + return 0;
> +}
> +
> void aie2_hwctx_suspend(struct amdxdna_client *client)
> {
> struct amdxdna_dev *xdna = client->xdna;
> - struct amdxdna_hwctx *hwctx;
> - unsigned long hwctx_id;
>
> /*
> * Command timeout is unlikely. But if it happens, it doesn't
> @@ -145,19 +154,22 @@ void aie2_hwctx_suspend(struct amdxdna_client *client)
> * and abort all commands.
> */
> drm_WARN_ON(&xdna->ddev, !mutex_is_locked(&xdna->dev_lock));
> - guard(mutex)(&client->hwctx_lock);
> - amdxdna_for_each_hwctx(client, hwctx_id, hwctx) {
> - aie2_hwctx_wait_for_idle(hwctx);
> - aie2_hwctx_stop(xdna, hwctx, NULL);
> - aie2_hwctx_status_shift_stop(hwctx);
> - }
> + amdxdna_hwctx_walk(client, NULL, aie2_hwctx_suspend_cb);
> +}
> +
> +static int aie2_hwctx_resume_cb(struct amdxdna_hwctx *hwctx, void *arg)
> +{
> + struct amdxdna_dev *xdna = hwctx->client->xdna;
> +
> + aie2_hwctx_status_restore(hwctx);
> + aie2_hwctx_restart(xdna, hwctx);
> +
> + return 0;
return aie2_hwctx_restart(xdna, hwctx);
> }
>
> void aie2_hwctx_resume(struct amdxdna_client *client)
> {
> struct amdxdna_dev *xdna = client->xdna;
> - struct amdxdna_hwctx *hwctx;
> - unsigned long hwctx_id;
>
> /*
> * The resume path cannot guarantee that mailbox channel can be
> @@ -165,11 +177,7 @@ void aie2_hwctx_resume(struct amdxdna_client *client)
> * mailbox channel, error will return.
> */
> drm_WARN_ON(&xdna->ddev, !mutex_is_locked(&xdna->dev_lock));
> - guard(mutex)(&client->hwctx_lock);
> - amdxdna_for_each_hwctx(client, hwctx_id, hwctx) {
> - aie2_hwctx_status_restore(hwctx);
> - aie2_hwctx_restart(xdna, hwctx);
> - }
> + amdxdna_hwctx_walk(client, NULL, aie2_hwctx_resume_cb);
> }
>
> static void
> diff --git a/drivers/accel/amdxdna/aie2_message.c
> b/drivers/accel/amdxdna/aie2_message.c
> index 82412eec9a4b..9caad083543d 100644
> --- a/drivers/accel/amdxdna/aie2_message.c
> +++ b/drivers/accel/amdxdna/aie2_message.c
> @@ -290,18 +290,25 @@ int aie2_map_host_buf(struct amdxdna_dev_hdl *ndev, u32
> context_id, u64 addr, u6
> return 0;
> }
>
> +static int amdxdna_hwctx_col_map(struct amdxdna_hwctx *hwctx, void *arg)
> +{
> + u32 *bitmap = arg;
> +
> + *bitmap |= GENMASK(hwctx->start_col + hwctx->num_col - 1,
> hwctx->start_col);
> +
> + return 0;
> +}
> +
> int aie2_query_status(struct amdxdna_dev_hdl *ndev, char __user *buf,
> u32 size, u32 *cols_filled)
> {
> DECLARE_AIE2_MSG(aie_column_info, MSG_OP_QUERY_COL_STATUS);
> struct amdxdna_dev *xdna = ndev->xdna;
> struct amdxdna_client *client;
> - struct amdxdna_hwctx *hwctx;
> - unsigned long hwctx_id;
> dma_addr_t dma_addr;
> u32 aie_bitmap = 0;
> u8 *buff_addr;
> - int ret, idx;
> + int ret;
>
> buff_addr = dma_alloc_noncoherent(xdna->ddev.dev, size, &dma_addr,
> DMA_FROM_DEVICE, GFP_KERNEL);
> @@ -309,12 +316,8 @@ int aie2_query_status(struct amdxdna_dev_hdl *ndev, char
> __user *buf,
> return -ENOMEM;
>
> /* Go through each hardware context and mark the AIE columns that are
> active */
> - list_for_each_entry(client, &xdna->client_list, node) {
> - idx = srcu_read_lock(&client->hwctx_srcu);
> - amdxdna_for_each_hwctx(client, hwctx_id, hwctx)
> - aie_bitmap |= amdxdna_hwctx_col_map(hwctx);
> - srcu_read_unlock(&client->hwctx_srcu, idx);
> - }
> + list_for_each_entry(client, &xdna->client_list, node)
> + amdxdna_hwctx_walk(client, &aie_bitmap, amdxdna_hwctx_col_map);
>
> *cols_filled = 0;
> req.dump_buff_addr = dma_addr;
> diff --git a/drivers/accel/amdxdna/aie2_pci.c
> b/drivers/accel/amdxdna/aie2_pci.c
> index 6fc3191c3097..b3ae03d05fb0 100644
> --- a/drivers/accel/amdxdna/aie2_pci.c
> +++ b/drivers/accel/amdxdna/aie2_pci.c
> @@ -10,6 +10,7 @@
> #include <drm/drm_managed.h>
> #include <drm/drm_print.h>
> #include <drm/gpu_scheduler.h>
> +#include <linux/cleanup.h>
> #include <linux/errno.h>
> #include <linux/firmware.h>
> #include <linux/iommu.h>
> @@ -779,65 +780,56 @@ static int aie2_get_clock_metadata(struct
> amdxdna_client *client,
> return ret;
> }
>
> +static int aie2_hwctx_status_cb(struct amdxdna_hwctx *hwctx, void *arg)
> +{
> + struct amdxdna_drm_query_hwctx __user *buf, *tmp __free(kfree) = NULL;
> + struct amdxdna_drm_get_info *get_info_args = arg;
> +
> + if (get_info_args->buffer_size < sizeof(*tmp))
> + return -EINVAL;
> +
> + tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
> + if (!tmp)
> + return -ENOMEM;
> +
> + tmp->pid = hwctx->client->pid;
> + tmp->context_id = hwctx->id;
> + tmp->start_col = hwctx->start_col;
> + tmp->num_col = hwctx->num_col;
> + tmp->command_submissions = hwctx->priv->seq;
> + tmp->command_completions = hwctx->priv->completed;
> +
> + buf = u64_to_user_ptr(get_info_args->buffer);
> +
> + if (copy_to_user(buf, tmp, sizeof(*tmp)))
> + return -EFAULT;
> +
> + get_info_args->buffer += sizeof(*tmp);
> + get_info_args->buffer_size -= sizeof(*tmp);
> +
> + return 0;
> +}
> +
> static int aie2_get_hwctx_status(struct amdxdna_client *client,
> struct amdxdna_drm_get_info *args)
> {
> - struct amdxdna_drm_query_hwctx __user *buf;
> struct amdxdna_dev *xdna = client->xdna;
> - struct amdxdna_drm_query_hwctx *tmp;
> + struct amdxdna_drm_get_info info_args;
> struct amdxdna_client *tmp_client;
> - struct amdxdna_hwctx *hwctx;
> - unsigned long hwctx_id;
> - bool overflow = false;
> - u32 req_bytes = 0;
> - u32 hw_i = 0;
> - int ret = 0;
> - int idx;
> + int ret;
>
> drm_WARN_ON(&xdna->ddev, !mutex_is_locked(&xdna->dev_lock));
>
> - tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
> - if (!tmp)
> - return -ENOMEM;
> + info_args.buffer = args->buffer;
> + info_args.buffer_size = args->buffer_size;
>
> - buf = u64_to_user_ptr(args->buffer);
> list_for_each_entry(tmp_client, &xdna->client_list, node) {
> - idx = srcu_read_lock(&tmp_client->hwctx_srcu);
> - amdxdna_for_each_hwctx(tmp_client, hwctx_id, hwctx) {
> - req_bytes += sizeof(*tmp);
> - if (args->buffer_size < req_bytes) {
> - /* Continue iterating to get the required size
> */
> - overflow = true;
> - continue;
> - }
> -
> - memset(tmp, 0, sizeof(*tmp));
> - tmp->pid = tmp_client->pid;
> - tmp->context_id = hwctx->id;
> - tmp->start_col = hwctx->start_col;
> - tmp->num_col = hwctx->num_col;
> - tmp->command_submissions = hwctx->priv->seq;
> - tmp->command_completions = hwctx->priv->completed;
> -
> - if (copy_to_user(&buf[hw_i], tmp, sizeof(*tmp))) {
> - ret = -EFAULT;
> - srcu_read_unlock(&tmp_client->hwctx_srcu, idx);
> - goto out;
> - }
> - hw_i++;
> - }
> - srcu_read_unlock(&tmp_client->hwctx_srcu, idx);
> - }
> -
> - if (overflow) {
> - XDNA_ERR(xdna, "Invalid buffer size. Given: %u Need: %u.",
> - args->buffer_size, req_bytes);
> - ret = -EINVAL;
> + ret = amdxdna_hwctx_walk(tmp_client, &info_args,
> aie2_hwctx_status_cb);
> + if (ret)
> + break;
> }
>
> -out:
> - kfree(tmp);
> - args->buffer_size = req_bytes;
> + args->buffer_size = (u32)(info_args.buffer - args->buffer);
> return ret;
> }
>
> diff --git a/drivers/accel/amdxdna/amdxdna_ctx.c
> b/drivers/accel/amdxdna/amdxdna_ctx.c
> index b47a7f8e9017..4bfe4ef20550 100644
> --- a/drivers/accel/amdxdna/amdxdna_ctx.c
> +++ b/drivers/accel/amdxdna/amdxdna_ctx.c
> @@ -68,14 +68,30 @@ static void amdxdna_hwctx_destroy_rcu(struct
> amdxdna_hwctx *hwctx,
> synchronize_srcu(ss);
>
> /* At this point, user is not able to submit new commands */
> - mutex_lock(&xdna->dev_lock);
> xdna->dev_info->ops->hwctx_fini(hwctx);
> - mutex_unlock(&xdna->dev_lock);
>
> kfree(hwctx->name);
> kfree(hwctx);
> }
>
> +int amdxdna_hwctx_walk(struct amdxdna_client *client, void *arg,
> + int (*walk)(struct amdxdna_hwctx *hwctx, void *arg))
> +{
> + struct amdxdna_hwctx *hwctx;
> + unsigned long hwctx_id;
> + int ret = 0, idx;
> +
> + idx = srcu_read_lock(&client->hwctx_srcu);
> + amdxdna_for_each_hwctx(client, hwctx_id, hwctx) {
> + ret = walk(hwctx, arg);
> + if (ret)
> + break;
> + }
> + srcu_read_unlock(&client->hwctx_srcu, idx);
> +
> + return ret;
> +}
> +
> void *amdxdna_cmd_get_payload(struct amdxdna_gem_obj *abo, u32 *size)
> {
> struct amdxdna_cmd *cmd = abo->mem.kva;
> @@ -126,16 +142,12 @@ void amdxdna_hwctx_remove_all(struct amdxdna_client
> *client)
> struct amdxdna_hwctx *hwctx;
> unsigned long hwctx_id;
>
> - mutex_lock(&client->hwctx_lock);
> amdxdna_for_each_hwctx(client, hwctx_id, hwctx) {
> XDNA_DBG(client->xdna, "PID %d close HW context %d",
> client->pid, hwctx->id);
> xa_erase(&client->hwctx_xa, hwctx->id);
> - mutex_unlock(&client->hwctx_lock);
> amdxdna_hwctx_destroy_rcu(hwctx, &client->hwctx_srcu);
> - mutex_lock(&client->hwctx_lock);
> }
> - mutex_unlock(&client->hwctx_lock);
> }
>
> int amdxdna_drm_create_hwctx_ioctl(struct drm_device *dev, void *data,
> struct drm_file *filp)
> @@ -225,6 +237,7 @@ int amdxdna_drm_destroy_hwctx_ioctl(struct drm_device
> *dev, void *data, struct d
> if (!drm_dev_enter(dev, &idx))
> return -ENODEV;
>
> + mutex_lock(&xdna->dev_lock);
> hwctx = xa_erase(&client->hwctx_xa, args->handle);
> if (!hwctx) {
> ret = -EINVAL;
> @@ -241,6 +254,7 @@ int amdxdna_drm_destroy_hwctx_ioctl(struct drm_device
> *dev, void *data, struct d
>
> XDNA_DBG(xdna, "PID %d destroyed HW context %d", client->pid,
> args->handle);
> out:
> + mutex_unlock(&xdna->dev_lock);
> drm_dev_exit(idx);
> return ret;
> }
> diff --git a/drivers/accel/amdxdna/amdxdna_ctx.h
> b/drivers/accel/amdxdna/amdxdna_ctx.h
> index c652229547a3..7cd7a55936f0 100644
> --- a/drivers/accel/amdxdna/amdxdna_ctx.h
> +++ b/drivers/accel/amdxdna/amdxdna_ctx.h
> @@ -139,14 +139,10 @@ amdxdna_cmd_get_state(struct amdxdna_gem_obj *abo)
> void *amdxdna_cmd_get_payload(struct amdxdna_gem_obj *abo, u32 *size);
> int amdxdna_cmd_get_cu_idx(struct amdxdna_gem_obj *abo);
>
> -static inline u32 amdxdna_hwctx_col_map(struct amdxdna_hwctx *hwctx)
> -{
> - return GENMASK(hwctx->start_col + hwctx->num_col - 1,
> - hwctx->start_col);
> -}
> -
> void amdxdna_sched_job_cleanup(struct amdxdna_sched_job *job);
> void amdxdna_hwctx_remove_all(struct amdxdna_client *client);
> +int amdxdna_hwctx_walk(struct amdxdna_client *client, void *arg,
> + int (*walk)(struct amdxdna_hwctx *hwctx, void *arg));
>
> int amdxdna_cmd_submit(struct amdxdna_client *client,
> u32 cmd_bo_hdls, u32 *arg_bo_hdls, u32 arg_bo_cnt,
> diff --git a/drivers/accel/amdxdna/amdxdna_pci_drv.c
> b/drivers/accel/amdxdna/amdxdna_pci_drv.c
> index fbca94183f96..8ef5e4f27f5e 100644
> --- a/drivers/accel/amdxdna/amdxdna_pci_drv.c
> +++ b/drivers/accel/amdxdna/amdxdna_pci_drv.c
> @@ -81,7 +81,6 @@ static int amdxdna_drm_open(struct drm_device *ddev, struct
> drm_file *filp)
> ret = -ENODEV;
> goto unbind_sva;
> }
> - mutex_init(&client->hwctx_lock);
> init_srcu_struct(&client->hwctx_srcu);
> xa_init_flags(&client->hwctx_xa, XA_FLAGS_ALLOC);
> mutex_init(&client->mm_lock);
> @@ -116,7 +115,6 @@ static void amdxdna_drm_close(struct drm_device *ddev,
> struct drm_file *filp)
>
> xa_destroy(&client->hwctx_xa);
> cleanup_srcu_struct(&client->hwctx_srcu);
> - mutex_destroy(&client->hwctx_lock);
> mutex_destroy(&client->mm_lock);
> if (client->dev_heap)
> drm_gem_object_put(to_gobj(client->dev_heap));
> @@ -142,8 +140,8 @@ static int amdxdna_flush(struct file *f, fl_owner_t id)
>
> mutex_lock(&xdna->dev_lock);
> list_del_init(&client->node);
> - mutex_unlock(&xdna->dev_lock);
> amdxdna_hwctx_remove_all(client);
> + mutex_unlock(&xdna->dev_lock);
>
> drm_dev_exit(idx);
> return 0;
> @@ -330,11 +328,8 @@ static void amdxdna_remove(struct pci_dev *pdev)
> struct amdxdna_client, node);
> while (client) {
> list_del_init(&client->node);
> - mutex_unlock(&xdna->dev_lock);
> -
> amdxdna_hwctx_remove_all(client);
>
> - mutex_lock(&xdna->dev_lock);
> client = list_first_entry_or_null(&xdna->client_list,
> struct amdxdna_client, node);
> }
> diff --git a/drivers/accel/amdxdna/amdxdna_pci_drv.h
> b/drivers/accel/amdxdna/amdxdna_pci_drv.h
> index 40bbb3c06320..b6b3b424d1d5 100644
> --- a/drivers/accel/amdxdna/amdxdna_pci_drv.h
> +++ b/drivers/accel/amdxdna/amdxdna_pci_drv.h
> @@ -116,8 +116,6 @@ struct amdxdna_device_id {
> struct amdxdna_client {
> struct list_head node;
> pid_t pid;
> - struct mutex hwctx_lock; /* protect hwctx */
> - /* do NOT wait this srcu when hwctx_lock is held */
> struct srcu_struct hwctx_srcu;
> struct xarray hwctx_xa;
> u32 next_hwctxid;
