diff options
Diffstat (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c')
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c | 45 |
1 files changed, 32 insertions, 13 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c index 64c519cd7395..d88523568b62 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c @@ -35,10 +35,13 @@ * PASIDs are global address space identifiers that can be shared * between the GPU, an IOMMU and the driver. VMs on different devices * may use the same PASID if they share the same address - * space. Therefore PASIDs are allocated using a global IDA. VMs are - * looked up from the PASID per amdgpu_device. + * space. Therefore PASIDs are allocated using IDR cyclic allocator + * (similar to kernel PID allocation) which naturally delays reuse. + * VMs are looked up from the PASID per amdgpu_device. */ -static DEFINE_IDA(amdgpu_pasid_ida); + +static DEFINE_IDR(amdgpu_pasid_idr); +static DEFINE_SPINLOCK(amdgpu_pasid_idr_lock); /* Helper to free pasid from a fence callback */ struct amdgpu_pasid_cb { @@ -50,8 +53,8 @@ struct amdgpu_pasid_cb { * amdgpu_pasid_alloc - Allocate a PASID * @bits: Maximum width of the PASID in bits, must be at least 1 * - * Allocates a PASID of the given width while keeping smaller PASIDs - * available if possible. + * Uses kernel's IDR cyclic allocator (same as PID allocation). + * Allocates sequentially with automatic wrap-around. * * Returns a positive integer on success. Returns %-EINVAL if bits==0. * Returns %-ENOSPC if no PASID was available. Returns %-ENOMEM on @@ -59,14 +62,15 @@ struct amdgpu_pasid_cb { */ int amdgpu_pasid_alloc(unsigned int bits) { - int pasid = -EINVAL; + int pasid; - for (bits = min(bits, 31U); bits > 0; bits--) { - pasid = ida_alloc_range(&amdgpu_pasid_ida, 1U << (bits - 1), - (1U << bits) - 1, GFP_KERNEL); - if (pasid != -ENOSPC) - break; - } + if (bits == 0) + return -EINVAL; + + spin_lock(&amdgpu_pasid_idr_lock); + pasid = idr_alloc_cyclic(&amdgpu_pasid_idr, NULL, 1, + 1U << bits, GFP_KERNEL); + spin_unlock(&amdgpu_pasid_idr_lock); if (pasid >= 0) trace_amdgpu_pasid_allocated(pasid); @@ -81,7 +85,10 @@ int amdgpu_pasid_alloc(unsigned int bits) void amdgpu_pasid_free(u32 pasid) { trace_amdgpu_pasid_freed(pasid); - ida_free(&amdgpu_pasid_ida, pasid); + + spin_lock(&amdgpu_pasid_idr_lock); + idr_remove(&amdgpu_pasid_idr, pasid); + spin_unlock(&amdgpu_pasid_idr_lock); } static void amdgpu_pasid_free_cb(struct dma_fence *fence, @@ -616,3 +623,15 @@ void amdgpu_vmid_mgr_fini(struct amdgpu_device *adev) } } } + +/** + * amdgpu_pasid_mgr_cleanup - cleanup PASID manager + * + * Cleanup the IDR allocator. + */ +void amdgpu_pasid_mgr_cleanup(void) +{ + spin_lock(&amdgpu_pasid_idr_lock); + idr_destroy(&amdgpu_pasid_idr); + spin_unlock(&amdgpu_pasid_idr_lock); +} |