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authorJoel Fernandes <joelagnelf@nvidia.com>2026-07-18 13:15:36 -0400
committerPaul E. McKenney <paulmck@kernel.org>2026-07-23 10:39:57 -0700
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scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
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+.. SPDX-License-Identifier: GPL-2.0+
+
+=========================
+ drm/Panthor CSF driver
+=========================
+
+.. _panthor-usage-stats:
+
+Panthor DRM client usage stats implementation
+==============================================
+
+The drm/Panthor driver implements the DRM client usage stats specification as
+documented in :ref:`drm-client-usage-stats`.
+
+Example of the output showing the implemented key value pairs and entirety of
+the currently possible format options:
+
+::
+ pos: 0
+ flags: 02400002
+ mnt_id: 29
+ ino: 491
+ drm-driver: panthor
+ drm-client-id: 10
+ drm-engine-panthor: 111110952750 ns
+ drm-cycles-panthor: 94439687187
+ drm-maxfreq-panthor: 1000000000 Hz
+ drm-curfreq-panthor: 1000000000 Hz
+ panthor-resident-memory: 10396 KiB
+ panthor-active-memory: 10396 KiB
+ drm-total-memory: 16480 KiB
+ drm-shared-memory: 0
+ drm-active-memory: 16200 KiB
+ drm-resident-memory: 16480 KiB
+ drm-purgeable-memory: 0
+
+Possible `drm-engine-` key names are: `panthor`.
+`drm-curfreq-` values convey the current operating frequency for that engine.
+
+Users must bear in mind that engine and cycle sampling are disabled by default,
+because of power saving concerns. `fdinfo` users and benchmark applications which
+query the fdinfo file must make sure to toggle the job profiling status of the
+driver by writing into the appropriate sysfs node::
+
+ echo <N> > /sys/bus/platform/drivers/panthor/[a-f0-9]*.gpu/profiling
+
+Where `N` is a bit mask where cycle and timestamp sampling are respectively
+enabled by the first and second bits.
+
+Possible `panthor-*-memory` keys are: `active` and `resident`.
+These values convey the sizes of the internal driver-owned shmem BO's that
+aren't exposed to user-space through a DRM handle, like queue ring buffers,
+sync object arrays and heap chunks. Because they are all allocated and pinned
+at creation time, only `panthor-resident-memory` is necessary to tell us their
+size. `panthor-active-memory` shows the size of kernel BO's associated with
+VM's and groups currently being scheduled for execution by the GPU.