From: Ben Skeggs Date: Wed, 1 Nov 2017 03:56:19 +1000 Subject: drm/nouveau/imem/nv50: move slow-path locking into rd/wr functions Git-commit: af515ec8d3fbd8376513eee9648a52d5ab92bbac Patch-mainline: v4.15-rc1 References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166 This is to simplify upcoming changes. The slow-path is something that currently occurs during bootstrap of the BAR2 VMM, while backing up an object during suspend/resume, or when BAR2 address space runs out. The latter is a real problem that can happen at runtime, and occurs in Fedora 26 already (due to some change that causes a lot of channels to be created at login), so ideally we'd prefer not to make it any slower. We'd also like suspend/resume speed to not suffer. Upcoming commits will solve those problems in a better way, making the extra overhead of moving the locking here a non-issue. Signed-off-by: Ben Skeggs Acked-by: Petr Tesarik --- drivers/gpu/drm/nouveau/nvkm/subdev/instmem/nv50.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) --- a/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/nv50.c +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/nv50.c @@ -31,8 +31,6 @@ struct nv50_instmem { struct nvkm_instmem base; - unsigned long lock_flags; - spinlock_t lock; u64 addr; }; @@ -57,12 +55,15 @@ nv50_instobj_wr32_slow(struct nvkm_memor struct nvkm_device *device = imem->base.subdev.device; u64 base = (iobj->mem->offset + offset) & 0xffffff00000ULL; u64 addr = (iobj->mem->offset + offset) & 0x000000fffffULL; + unsigned long flags; + spin_lock_irqsave(&imem->base.lock, flags); if (unlikely(imem->addr != base)) { nvkm_wr32(device, 0x001700, base >> 16); imem->addr = base; } nvkm_wr32(device, 0x700000 + addr, data); + spin_unlock_irqrestore(&imem->base.lock, flags); } static u32 @@ -74,12 +75,15 @@ nv50_instobj_rd32_slow(struct nvkm_memor u64 base = (iobj->mem->offset + offset) & 0xffffff00000ULL; u64 addr = (iobj->mem->offset + offset) & 0x000000fffffULL; u32 data; + unsigned long flags; + spin_lock_irqsave(&imem->base.lock, flags); if (unlikely(imem->addr != base)) { nvkm_wr32(device, 0x001700, base >> 16); imem->addr = base; } data = nvkm_rd32(device, 0x700000 + addr); + spin_unlock_irqrestore(&imem->base.lock, flags); return data; } @@ -127,8 +131,6 @@ nv50_instobj_map(struct nvkm_memory *mem static void nv50_instobj_release(struct nvkm_memory *memory) { - struct nv50_instmem *imem = nv50_instobj(memory)->imem; - spin_unlock_irqrestore(&imem->lock, imem->lock_flags); } static void __iomem * @@ -137,15 +139,12 @@ nv50_instobj_acquire(struct nvkm_memory struct nv50_instobj *iobj = nv50_instobj(memory); struct nv50_instmem *imem = iobj->imem; struct nvkm_vm *vm; - unsigned long flags; if (!iobj->map && (vm = nvkm_bar_bar2_vmm(imem->base.subdev.device))) nv50_instobj_kmap(iobj, vm); if (!IS_ERR_OR_NULL(iobj->map)) return iobj->map; - spin_lock_irqsave(&imem->lock, flags); - imem->lock_flags = flags; return NULL; } @@ -254,7 +253,6 @@ nv50_instmem_new(struct nvkm_device *dev if (!(imem = kzalloc(sizeof(*imem), GFP_KERNEL))) return -ENOMEM; nvkm_instmem_ctor(&nv50_instmem, device, index, &imem->base); - spin_lock_init(&imem->lock); *pimem = &imem->base; return 0; }