On Fri, Mar 1, 2024 at 10:54 AM Rob Clark <robdcl...@gmail.com> wrote:
> From: Rob Clark <robdcl...@chromium.org> > > Perfetto can use these traces to track global and per-process GPU memory > usage. > > Signed-off-by: Rob Clark <robdcl...@chromium.org> > --- > I realized the tracepoint that perfetto uses to show GPU memory usage > globally and per-process was already upstream, but with no users. > > This overlaps a bit with fdinfo, but ftrace is a lighter weight > mechanism and fits better with perfetto (plus is already supported in > trace_processor and perfetto UI, whereas something fdinfo based would > require new code to be added in perfetto. > > We could probably do this more globally (ie. drm_gem_get/put_pages() and > drm_gem_handle_create_tail()/drm_gem_object_release_handle() if folks > prefer. Not sure where that leaves the TTM drivers. > > drivers/gpu/drm/msm/Kconfig | 1 + > drivers/gpu/drm/msm/msm_drv.h | 5 +++++ > drivers/gpu/drm/msm/msm_gem.c | 37 +++++++++++++++++++++++++++++++++++ > drivers/gpu/drm/msm/msm_gpu.h | 8 ++++++++ > 4 files changed, 51 insertions(+) > > diff --git a/drivers/gpu/drm/msm/Kconfig b/drivers/gpu/drm/msm/Kconfig > index f202f26adab2..e4c912fcaf22 100644 > --- a/drivers/gpu/drm/msm/Kconfig > +++ b/drivers/gpu/drm/msm/Kconfig > @@ -33,6 +33,7 @@ config DRM_MSM > select PM_OPP > select NVMEM > select PM_GENERIC_DOMAINS > + select TRACE_GPU_MEM > help > DRM/KMS driver for MSM/snapdragon. > > diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h > index 16a7cbc0b7dd..cb8f7e804b5b 100644 > --- a/drivers/gpu/drm/msm/msm_drv.h > +++ b/drivers/gpu/drm/msm/msm_drv.h > @@ -137,6 +137,11 @@ struct msm_drm_private { > struct msm_rd_state *hangrd; /* debugfs to dump hanging submits > */ > struct msm_perf_state *perf; > > + /** > + * total_mem: Total/global amount of memory backing GEM objects. > + */ > + atomic64_t total_mem; > + > /** > * List of all GEM objects (mainly for debugfs, protected by > obj_lock > * (acquire before per GEM object lock) > diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c > index 175ee4ab8a6f..e04c4af5d154 100644 > --- a/drivers/gpu/drm/msm/msm_gem.c > +++ b/drivers/gpu/drm/msm/msm_gem.c > @@ -12,6 +12,9 @@ > #include <linux/pfn_t.h> > > #include <drm/drm_prime.h> > +#include <drm/drm_file.h> > + > +#include <trace/events/gpu_mem.h> > > #include "msm_drv.h" > #include "msm_fence.h" > @@ -33,6 +36,34 @@ static bool use_pages(struct drm_gem_object *obj) > return !msm_obj->vram_node; > } > > +static void update_device_mem(struct msm_drm_private *priv, ssize_t size) > +{ > + uint64_t total_mem = atomic64_add_return(size, &priv->total_mem); > + trace_gpu_mem_total(0, 0, total_mem); > +} > + > +static void update_ctx_mem(struct drm_file *file, ssize_t size) > +{ > + struct msm_file_private *ctx = file->driver_priv; > + uint64_t ctx_mem = atomic64_add_return(size, &ctx->ctx_mem); > + > + rcu_read_lock(); /* Locks file->pid! */ > + trace_gpu_mem_total(0, pid_nr(file->pid), ctx_mem); > + rcu_read_unlock(); > + > +} > + > +static int msm_gem_open(struct drm_gem_object *obj, struct drm_file *file) > +{ > + update_ctx_mem(file, obj->size); > + return 0; > +} > + > +static void msm_gem_close(struct drm_gem_object *obj, struct drm_file > *file) > +{ > + update_ctx_mem(file, -obj->size); > +} > + > /* > * Cache sync.. this is a bit over-complicated, to fit dma-mapping > * API. Really GPU cache is out of scope here (handled on cmdstream) > @@ -156,6 +187,8 @@ static struct page **get_pages(struct drm_gem_object > *obj) > return p; > } > > + update_device_mem(dev->dev_private, obj->size); > + > msm_obj->pages = p; > > msm_obj->sgt = drm_prime_pages_to_sg(obj->dev, p, npages); > @@ -209,6 +242,8 @@ static void put_pages(struct drm_gem_object *obj) > msm_obj->sgt = NULL; > } > > + update_device_mem(obj->dev->dev_private, -obj->size); > + > if (use_pages(obj)) > drm_gem_put_pages(obj, msm_obj->pages, true, > false); > else > @@ -1118,6 +1153,8 @@ static const struct vm_operations_struct vm_ops = { > > static const struct drm_gem_object_funcs msm_gem_object_funcs = { > .free = msm_gem_free_object, > + .open = msm_gem_open, > + .close = msm_gem_close, > .pin = msm_gem_prime_pin, > .unpin = msm_gem_prime_unpin, > .get_sg_table = msm_gem_prime_get_sg_table, > diff --git a/drivers/gpu/drm/msm/msm_gpu.h b/drivers/gpu/drm/msm/msm_gpu.h > index 2bfcb222e353..f7d2a7d6f8cc 100644 > --- a/drivers/gpu/drm/msm/msm_gpu.h > +++ b/drivers/gpu/drm/msm/msm_gpu.h > @@ -428,6 +428,14 @@ struct msm_file_private { > * level. > */ > struct drm_sched_entity *entities[NR_SCHED_PRIORITIES * > MSM_GPU_MAX_RINGS]; > + > + /** > + * ctx_mem: > + * > + * Total amount of memory of GEM buffers with handles attached for > + * this context. > + */ > + atomic64_t ctx_mem; > }; > Just for added context, past discussions on TRACE_GPU_MEM: https://lists.freedesktop.org/archives/dri-devel/2021-October/328260.html https://lists.freedesktop.org/archives/dri-devel/2021-January/295120.html Some have even suggested deleting the tracepoint altogether. Personally, I think we should land an internal user in a non-breaking way, since userspace (Perfetto) already depends on it. Right now, we're in limbo for multiple years ... > /** > -- > 2.44.0 > >