Messages in this thread |  | | Date | Mon, 15 May 2023 12:46:54 +0100 | | Subject | Re: [PATCH v3 5/9] drm: Add fdinfo memory stats | | From | Tvrtko Ursulin <> |
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On 01/05/2023 19:44, Rob Clark wrote: > From: Rob Clark <robdclark@chromium.org> > > Add support to dump GEM stats to fdinfo. > > v2: Fix typos, change size units to match docs, use div_u64 > v3: Do it in core > v4: more kerneldoc > v5: doc fixes > > Signed-off-by: Rob Clark <robdclark@chromium.org> > Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com> > Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> > --- > Documentation/gpu/drm-usage-stats.rst | 54 +++++++++++---- > drivers/gpu/drm/drm_file.c | 99 ++++++++++++++++++++++++++- > include/drm/drm_file.h | 28 ++++++++ > include/drm/drm_gem.h | 30 ++++++++ > 4 files changed, 198 insertions(+), 13 deletions(-) > > diff --git a/Documentation/gpu/drm-usage-stats.rst b/Documentation/gpu/drm-usage-stats.rst > index 552195fb1ea3..d012eb56885e 100644 > --- a/Documentation/gpu/drm-usage-stats.rst > +++ b/Documentation/gpu/drm-usage-stats.rst > @@ -45,37 +45,43 @@ Mandatory fully standardised keys > --------------------------------- > > - drm-driver: <str> > > String shall contain the name this driver registered as via the respective > `struct drm_driver` data structure. > > Optional fully standardised keys > -------------------------------- > > +Identification > +^^^^^^^^^^^^^^ > + > - drm-pdev: <aaaa:bb.cc.d> > > For PCI devices this should contain the PCI slot address of the device in > question. > > - drm-client-id: <uint> > > Unique value relating to the open DRM file descriptor used to distinguish > duplicated and shared file descriptors. Conceptually the value should map 1:1 > to the in kernel representation of `struct drm_file` instances. > > Uniqueness of the value shall be either globally unique, or unique within the > scope of each device, in which case `drm-pdev` shall be present as well. > > Userspace should make sure to not double account any usage statistics by using > the above described criteria in order to associate data to individual clients. > > +Utilization > +^^^^^^^^^^^ > + > - drm-engine-<str>: <uint> ns > > GPUs usually contain multiple execution engines. Each shall be given a stable > and unique name (str), with possible values documented in the driver specific > documentation. > > Value shall be in specified time units which the respective GPU engine spent > busy executing workloads belonging to this client. > > Values are not required to be constantly monotonic if it makes the driver > @@ -86,32 +92,20 @@ value until a monotonic update is seen. > > - drm-engine-capacity-<str>: <uint> > > Engine identifier string must be the same as the one specified in the > drm-engine-<str> tag and shall contain a greater than zero number in case the > exported engine corresponds to a group of identical hardware engines. > > In the absence of this tag parser shall assume capacity of one. Zero capacity > is not allowed. > > -- drm-memory-<str>: <uint> [KiB|MiB] > - > -Each possible memory type which can be used to store buffer objects by the > -GPU in question shall be given a stable and unique name to be returned as the > -string here. > - > -Value shall reflect the amount of storage currently consumed by the buffer > -object belong to this client, in the respective memory region. > - > -Default unit shall be bytes with optional unit specifiers of 'KiB' or 'MiB' > -indicating kibi- or mebi-bytes. > - > - drm-cycles-<str>: <uint> > > Engine identifier string must be the same as the one specified in the > drm-engine-<str> tag and shall contain the number of busy cycles for the given > engine. > > Values are not required to be constantly monotonic if it makes the driver > implementation easier, but are required to catch up with the previously reported > larger value within a reasonable period. Upon observing a value lower than what > was previously read, userspace is expected to stay with that larger previous > @@ -119,20 +113,56 @@ value until a monotonic update is seen. > > - drm-maxfreq-<str>: <uint> [Hz|MHz|KHz] > > Engine identifier string must be the same as the one specified in the > drm-engine-<str> tag and shall contain the maximum frequency for the given > engine. Taken together with drm-cycles-<str>, this can be used to calculate > percentage utilization of the engine, whereas drm-engine-<str> only reflects > time active without considering what frequency the engine is operating as a > percentage of it's maximum frequency. > > +Memory > +^^^^^^ > + > +- drm-memory-<region>: <uint> [KiB|MiB] > + > +Each possible memory type which can be used to store buffer objects by the > +GPU in question shall be given a stable and unique name to be returned as the > +string here. The name "memory" is reserved to refer to normal system memory. > + > +Value shall reflect the amount of storage currently consumed by the buffer > +objects belong to this client, in the respective memory region. > + > +Default unit shall be bytes with optional unit specifiers of 'KiB' or 'MiB' > +indicating kibi- or mebi-bytes. > + > +- drm-shared-<region>: <uint> [KiB|MiB] > + > +The total size of buffers that are shared with another file (ie. have more > +than a single handle). > + > +- drm-total-<region>: <uint> [KiB|MiB] > + > +The total size of buffers that including shared and private memory. > + > +- drm-resident-<region>: <uint> [KiB|MiB] > + > +The total size of buffers that are resident in the specified region. > + > +- drm-purgeable-<region>: <uint> [KiB|MiB] > + > +The total size of buffers that are purgeable. > + > +- drm-active-<region>: <uint> [KiB|MiB] > + > +The total size of buffers that are active on one or more engines. > + > Implementation Details > ====================== > > Drivers should use drm_show_fdinfo() in their `struct file_operations`, and > implement &drm_driver.show_fdinfo if they wish to provide any stats which > are not provided by drm_show_fdinfo(). But even driver specific stats should > be documented above and where possible, aligned with other drivers. > > Driver specific implementations > ------------------------------- > diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c > index 6d5bdd684ae2..9321eb0bf020 100644 > --- a/drivers/gpu/drm/drm_file.c > +++ b/drivers/gpu/drm/drm_file.c > @@ -35,20 +35,21 @@ > #include <linux/dma-fence.h> > #include <linux/file.h> > #include <linux/module.h> > #include <linux/pci.h> > #include <linux/poll.h> > #include <linux/slab.h> > > #include <drm/drm_client.h> > #include <drm/drm_drv.h> > #include <drm/drm_file.h> > +#include <drm/drm_gem.h> > #include <drm/drm_print.h> > > #include "drm_crtc_internal.h" > #include "drm_internal.h" > #include "drm_legacy.h" > > /* from BKL pushdown */ > DEFINE_MUTEX(drm_global_mutex); > > bool drm_dev_needs_global_mutex(struct drm_device *dev) > @@ -864,23 +865,119 @@ EXPORT_SYMBOL(drm_send_event_locked); > void drm_send_event(struct drm_device *dev, struct drm_pending_event *e) > { > unsigned long irqflags; > > spin_lock_irqsave(&dev->event_lock, irqflags); > drm_send_event_helper(dev, e, 0); > spin_unlock_irqrestore(&dev->event_lock, irqflags); > } > EXPORT_SYMBOL(drm_send_event); > > +static void print_size(struct drm_printer *p, const char *stat, > + const char *region, size_t sz) > +{ > + const char *units[] = {"", " KiB", " MiB"}; > + unsigned u; > + > + for (u = 0; u < ARRAY_SIZE(units) - 1; u++) { > + if (sz < SZ_1K) > + break; > + sz = div_u64(sz, SZ_1K); > + } > + > + drm_printf(p, "drm-%s-%s:\t%zu%s\n", stat, region, sz, units[u]); > +} > + > +/** > + * drm_print_memory_stats - A helper to print memory stats > + * @p: The printer to print output to > + * @stats: The collected memory stats > + * @supported_status: Bitmask of optional stats which are available > + * @region: The memory region > + * > + */ > +void drm_print_memory_stats(struct drm_printer *p, > + const struct drm_memory_stats *stats, > + enum drm_gem_object_status supported_status, > + const char *region) > +{ > + print_size(p, "total", region, stats->private + stats->shared); > + print_size(p, "shared", region, stats->shared); > + print_size(p, "active", region, stats->active); > + > + if (supported_status & DRM_GEM_OBJECT_RESIDENT) > + print_size(p, "resident", region, stats->resident); > + > + if (supported_status & DRM_GEM_OBJECT_PURGEABLE) > + print_size(p, "purgeable", region, stats->purgeable); > +} > +EXPORT_SYMBOL(drm_print_memory_stats); > + > +/** > + * drm_show_memory_stats - Helper to collect and show standard fdinfo memory stats > + * @p: the printer to print output to > + * @file: the DRM file > + * > + * Helper to iterate over GEM objects with a handle allocated in the specified > + * file. > + */ > +void drm_show_memory_stats(struct drm_printer *p, struct drm_file *file) > +{ > + struct drm_gem_object *obj; > + struct drm_memory_stats status = {}; > + enum drm_gem_object_status supported_status; > + int id; > + > + spin_lock(&file->table_lock); > + idr_for_each_entry (&file->object_idr, obj, id) { > + enum drm_gem_object_status s = 0; > + > + if (obj->funcs && obj->funcs->status) { > + s = obj->funcs->status(obj); > + supported_status = DRM_GEM_OBJECT_RESIDENT | > + DRM_GEM_OBJECT_PURGEABLE;
I am slightly unsure if instead this mask shouldn't be returned by the driver callback. No action needed.
> + } > + > + if (obj->handle_count > 1) { > + status.shared += obj->size; > + } else { > + status.private += obj->size; > + } > + > + if (s & DRM_GEM_OBJECT_RESIDENT) { > + status.resident += obj->size; > + } else { > + /* If already purged or not yet backed by pages, don't > + * count it as purgeable: > + */ > + s &= ~DRM_GEM_OBJECT_PURGEABLE; > + } > + > + if (!dma_resv_test_signaled(obj->resv, dma_resv_usage_rw(true))) { > + status.active += obj->size; > + > + /* If still active, don't count as purgeable: */ > + s &= ~DRM_GEM_OBJECT_PURGEABLE; > + } > + > + if (s & DRM_GEM_OBJECT_PURGEABLE) > + status.purgeable += obj->size; > + } > + spin_unlock(&file->table_lock); > + > + drm_print_memory_stats(p, &status, supported_status, "memory"); > +} > +EXPORT_SYMBOL(drm_show_memory_stats); > + > /** > * drm_show_fdinfo - helper for drm file fops > - * @seq_file: output stream > + * @m: output stream > * @f: the device file instance > * > * Helper to implement fdinfo, for userspace to query usage stats, etc, of a > * process using the GPU. See also &drm_driver.show_fdinfo. > * > * For text output format description please see Documentation/gpu/drm-usage-stats.rst > */ > void drm_show_fdinfo(struct seq_file *m, struct file *f) > { > struct drm_file *file = f->private_data; > diff --git a/include/drm/drm_file.h b/include/drm/drm_file.h > index 6de6d0e9c634..f77540b97cd0 100644 > --- a/include/drm/drm_file.h > +++ b/include/drm/drm_file.h > @@ -34,20 +34,21 @@ > #include <linux/completion.h> > #include <linux/idr.h> > > #include <uapi/drm/drm.h> > > #include <drm/drm_prime.h> > > struct dma_fence; > struct drm_file; > struct drm_device; > +struct drm_printer; > struct device; > struct file; > > /* > * FIXME: Not sure we want to have drm_minor here in the end, but to avoid > * header include loops we need it here for now. > */ > > /* Note that the order of this enum is ABI (it determines > * /dev/dri/renderD* numbers). > @@ -433,15 +434,42 @@ int drm_event_reserve_init(struct drm_device *dev, > struct drm_file *file_priv, > struct drm_pending_event *p, > struct drm_event *e); > void drm_event_cancel_free(struct drm_device *dev, > struct drm_pending_event *p); > void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e); > void drm_send_event(struct drm_device *dev, struct drm_pending_event *e); > void drm_send_event_timestamp_locked(struct drm_device *dev, > struct drm_pending_event *e, > ktime_t timestamp); > + > +/** > + * struct drm_memory_stats - GEM object stats associated > + * @shared: Total size of GEM objects shared between processes > + * @private: Total size of GEM objects > + * @resident: Total size of GEM objects backing pages > + * @purgeable: Total size of GEM objects that can be purged (resident and not active) > + * @active: Total size of GEM objects active on one or more engines > + * > + * Used by drm_print_memory_stats() > + */ > +struct drm_memory_stats { > + u32 shared; > + u32 private; > + u32 resident; > + u32 purgeable; > + u32 active; > +};
u64 for these as agreed.
> + > +enum drm_gem_object_status; > + > +void drm_print_memory_stats(struct drm_printer *p, > + const struct drm_memory_stats *stats, > + enum drm_gem_object_status supported_status, > + const char *region); > + > +void drm_show_memory_stats(struct drm_printer *p, struct drm_file *file); > void drm_show_fdinfo(struct seq_file *m, struct file *f); > > struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags); > > #endif /* _DRM_FILE_H_ */ > diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h > index 189fd618ca65..9ebd2820ad1f 100644 > --- a/include/drm/drm_gem.h > +++ b/include/drm/drm_gem.h > @@ -35,20 +35,39 @@ > */ > > #include <linux/kref.h> > #include <linux/dma-resv.h> > > #include <drm/drm_vma_manager.h> > > struct iosys_map; > struct drm_gem_object; > > +/** > + * enum drm_gem_object_status - bitmask of object state for fdinfo reporting > + * @DRM_GEM_OBJECT_RESIDENT: object is resident in memory (ie. not unpinned) > + * @DRM_GEM_OBJECT_PURGEABLE: object marked as purgeable by userspace > + * > + * Bitmask of status used for fdinfo memory stats, see &drm_gem_object_funcs.status > + * and drm_show_fdinfo(). Note that an object can DRM_GEM_OBJECT_PURGEABLE if > + * it still active or not resident, in which case drm_show_fdinfo() will not > + * account for it as purgeable. So drivers do not need to check if the buffer > + * is idle and resident to return this bit. (Ie. userspace can mark a buffer > + * as purgeable even while it is still busy on the GPU.. it does not _actually_ > + * become puregeable until it becomes idle. The status gem object func does > + * not need to consider this.) > + */ > +enum drm_gem_object_status { > + DRM_GEM_OBJECT_RESIDENT = BIT(0), > + DRM_GEM_OBJECT_PURGEABLE = BIT(1), > +}; > + > /** > * struct drm_gem_object_funcs - GEM object functions > */ > struct drm_gem_object_funcs { > /** > * @free: > * > * Deconstructor for drm_gem_objects. > * > * This callback is mandatory. > @@ -167,20 +186,31 @@ struct drm_gem_object_funcs { > /** > * @evict: > * > * Evicts gem object out from memory. Used by the drm_gem_object_evict() > * helper. Returns 0 on success, -errno otherwise. > * > * This callback is optional. > */ > int (*evict)(struct drm_gem_object *obj); > > + /** > + * @status: > + * > + * The optional status callback can return additional object state > + * which determines which stats the object is counted against. The > + * callback is called under table_lock. Racing against object status > + * change is "harmless", and the callback can expect to not race > + * against object destruction.
Maybe mention the callback is called from drm_show_memory_stats?
> + */ > + enum drm_gem_object_status (*status)(struct drm_gem_object *obj); > + > /** > * @vm_ops: > * > * Virtual memory operations used with mmap. > * > * This is optional but necessary for mmap support. > */ > const struct vm_operations_struct *vm_ops; > }; >
With the u64 stats:
Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Regards,
Tvrtko
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