Commit Graph

6 Commits

Author SHA1 Message Date
Christian Gmeiner
95036d4c01 drm/v3d: Stop active perfmon if it is being destroyed
commit 21f1435b1e6b012a07c42f36b206d2b66fc8f13b upstream.

If the active performance monitor (`v3d->active_perfmon`) is being
destroyed, stop it first. Currently, the active perfmon is not
stopped during destruction, leaving the `v3d->active_perfmon` pointer
stale. This can lead to undefined behavior and instability.

This patch ensures that the active perfmon is stopped before being
destroyed, aligning with the behavior introduced in commit
7d1fd3638e ("drm/v3d: Stop the active perfmon before being destroyed").

Cc: stable@vger.kernel.org # v5.15+
Fixes: 26a4dc29b7 ("drm/v3d: Expose performance counters to userspace")
Signed-off-by: Christian Gmeiner <cgmeiner@igalia.com>
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241118221948.1758130-1-christian.gmeiner@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-21 13:50:09 +01:00
Maíra Canal
5abef60d14 drm/v3d: Enable Performance Counters before clearing them
[ Upstream commit c98b10496b2f3c4f576af3482c71aadcfcbf765e ]

On the Raspberry Pi 5, performance counters are not being cleared
when `v3d_perfmon_start()` is called, even though we write to the
CLR register. As a result, their values accumulate until they
overflow.

The expected behavior is for performance counters to reset to zero
at the start of a job. When the job finishes and the perfmon is
stopped, the counters should accurately reflect the values for that
specific job.

To ensure this behavior, the performance counters are now enabled
before being cleared. This allows the CLR register to function as
intended, zeroing the counter values when the job begins.

Fixes: 26a4dc29b7 ("drm/v3d: Expose performance counters to userspace")
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241204122831.17015-1-mcanal@igalia.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14 19:54:30 +01:00
Maíra Canal
0c9e9a3a48 drm/v3d: Stop the active perfmon before being destroyed
commit 7d1fd3638e upstream.

When running `kmscube` with one or more performance monitors enabled
via `GALLIUM_HUD`, the following kernel panic can occur:

[   55.008324] Unable to handle kernel paging request at virtual address 00000000052004a4
[   55.008368] Mem abort info:
[   55.008377]   ESR = 0x0000000096000005
[   55.008387]   EC = 0x25: DABT (current EL), IL = 32 bits
[   55.008402]   SET = 0, FnV = 0
[   55.008412]   EA = 0, S1PTW = 0
[   55.008421]   FSC = 0x05: level 1 translation fault
[   55.008434] Data abort info:
[   55.008442]   ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
[   55.008455]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[   55.008467]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[   55.008481] user pgtable: 4k pages, 39-bit VAs, pgdp=00000001046c6000
[   55.008497] [00000000052004a4] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
[   55.008525] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
[   55.008542] Modules linked in: rfcomm [...] vc4 v3d snd_soc_hdmi_codec drm_display_helper
gpu_sched drm_shmem_helper cec drm_dma_helper drm_kms_helper i2c_brcmstb
drm drm_panel_orientation_quirks snd_soc_core snd_compress snd_pcm_dmaengine snd_pcm snd_timer snd backlight
[   55.008799] CPU: 2 PID: 166 Comm: v3d_bin Tainted: G         C         6.6.47+rpt-rpi-v8 #1  Debian 1:6.6.47-1+rpt1
[   55.008824] Hardware name: Raspberry Pi 4 Model B Rev 1.5 (DT)
[   55.008838] pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   55.008855] pc : __mutex_lock.constprop.0+0x90/0x608
[   55.008879] lr : __mutex_lock.constprop.0+0x58/0x608
[   55.008895] sp : ffffffc080673cf0
[   55.008904] x29: ffffffc080673cf0 x28: 0000000000000000 x27: ffffff8106188a28
[   55.008926] x26: ffffff8101e78040 x25: ffffff8101baa6c0 x24: ffffffd9d989f148
[   55.008947] x23: ffffffda1c2a4008 x22: 0000000000000002 x21: ffffffc080673d38
[   55.008968] x20: ffffff8101238000 x19: ffffff8104f83188 x18: 0000000000000000
[   55.008988] x17: 0000000000000000 x16: ffffffda1bd04d18 x15: 00000055bb08bc90
[   55.009715] x14: 0000000000000000 x13: 0000000000000000 x12: ffffffda1bd4cbb0
[   55.010433] x11: 00000000fa83b2da x10: 0000000000001a40 x9 : ffffffda1bd04d04
[   55.011162] x8 : ffffff8102097b80 x7 : 0000000000000000 x6 : 00000000030a5857
[   55.011880] x5 : 00ffffffffffffff x4 : 0300000005200470 x3 : 0300000005200470
[   55.012598] x2 : ffffff8101238000 x1 : 0000000000000021 x0 : 0300000005200470
[   55.013292] Call trace:
[   55.013959]  __mutex_lock.constprop.0+0x90/0x608
[   55.014646]  __mutex_lock_slowpath+0x1c/0x30
[   55.015317]  mutex_lock+0x50/0x68
[   55.015961]  v3d_perfmon_stop+0x40/0xe0 [v3d]
[   55.016627]  v3d_bin_job_run+0x10c/0x2d8 [v3d]
[   55.017282]  drm_sched_main+0x178/0x3f8 [gpu_sched]
[   55.017921]  kthread+0x11c/0x128
[   55.018554]  ret_from_fork+0x10/0x20
[   55.019168] Code: f9400260 f1001c1f 54001ea9 927df000 (b9403401)
[   55.019776] ---[ end trace 0000000000000000 ]---
[   55.020411] note: v3d_bin[166] exited with preempt_count 1

This issue arises because, upon closing the file descriptor (which happens
when we interrupt `kmscube`), the active performance monitor is not
stopped. Although all perfmons are destroyed in `v3d_perfmon_close_file()`,
the active performance monitor's pointer (`v3d->active_perfmon`) is still
retained.

If `kmscube` is run again, the driver will attempt to stop the active
performance monitor using the stale pointer in `v3d->active_perfmon`.
However, this pointer is no longer valid because the previous process has
already terminated, and all performance monitors associated with it have
been destroyed and freed.

To fix this, when the active performance monitor belongs to a given
process, explicitly stop it before destroying and freeing it.

Cc: stable@vger.kernel.org # v5.15+
Closes: https://github.com/raspberrypi/linux/issues/6389
Fixes: 26a4dc29b7 ("drm/v3d: Expose performance counters to userspace")
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Juan A. Suarez <jasuarez@igalia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241004130625.918580-2-mcanal@igalia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-17 15:22:26 +02:00
Danilo Krummrich
604bda63bf
drm/v3d: use idr_init_base() to initialize v3d_priv->perfmon.idr
idr_init_base(), implemented by commit 6ce711f275 ("idr: Make 1-based
IDRs more efficient"), let us set an arbitrary base other than
idr_init(), which uses base 0.

Since, for this IDR, no ID < 1 is ever requested/allocated, using
idr_init_base(&idr, 1) avoids unnecessary tree walks.

Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220701190227.284783-1-dakr@redhat.com
2022-07-28 15:35:56 +01:00
Colin Ian King
ce7a1ecf3f drm/v3d: Fix null pointer dereference of pointer perfmon
In the unlikely event that pointer perfmon is null the WARN_ON return path
occurs after the pointer has already been deferenced. Fix this by only
dereferencing perfmon after it has been null checked.

Fixes: 26a4dc29b7 ("drm/v3d: Expose performance counters to userspace")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Juan A. Suarez <jasuarez@igalia.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220424183512.1365683-1-colin.i.king@gmail.com
2022-04-26 11:55:28 -01:00
Juan A. Suarez Romero
26a4dc29b7 drm/v3d: Expose performance counters to userspace
The V3D engine has several hardware performance counters that can of
interest for userspace performance analysis tools.

This exposes new ioctls to create and destroy performance monitor
objects, as well as to query the counter values.

Each created performance monitor object has an ID that can be attached
to CL/CSD submissions, so the driver enables the requested counters when
the job is submitted, and updates the performance monitor values when
the job is done.

It is up to the user to ensure all the jobs have been finished before
getting the performance monitor values. It is also up to the user to
properly synchronize BCL jobs when submitting jobs with different
performance monitors attached.

Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Emma Anholt <emma@anholt.net>
To: dri-devel@lists.freedesktop.org
Signed-off-by: Juan A. Suarez Romero <jasuarez@igalia.com>
Acked-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210608111541.461991-1-jasuarez@igalia.com
2021-07-21 00:19:59 +01:00