From: Arnd Bergmann <arnd@kernel.org>
To: Jani Nikula <jani.nikula@linux.intel.com>,
Rodrigo Vivi <rodrigo.vivi@intel.com>,
Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
Tvrtko Ursulin <tursulin@ursulin.net>,
David Airlie <airlied@gmail.com>, Simona Vetter <simona@ffwll.ch>
Cc: "Arnd Bergmann" <arnd@arndb.de>,
"Ville Syrjälä" <ville.syrjala@linux.intel.com>,
"Vinod Govindapillai" <vinod.govindapillai@intel.com>,
"Suraj Kandpal" <suraj.kandpal@intel.com>,
"Mitul Golani" <mitulkumar.ajitkumar.golani@intel.com>,
"Stanislav Lisovskiy" <stanislav.lisovskiy@intel.com>,
intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org,
dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: [PATCH] drm/i915/wm: reduce stack usage in skl_print_wm_changes()
Date: Fri, 20 Jun 2025 13:37:45 +0200 [thread overview]
Message-ID: <20250620113748.3869160-1-arnd@kernel.org> (raw)
From: Arnd Bergmann <arnd@arndb.de>
When KMSAN is enabled, this function causes has a rather excessive stack usage:
drivers/gpu/drm/i915/display/skl_watermark.c:2977:1: error: stack frame size (1432) exceeds limit (1408) in 'skl_compute_wm' [-Werror,-Wframe-larger-than]
This is apparently all caused by the varargs calls to drm_dbg_kms(). Inlining
this into skl_compute_wm() means that any function called by skl_compute_wm()
has its own stack on top of that.
Move the worst bit into a separate function marked as noinline_for_stack to
limit that to the one code path that actually needs it.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/gpu/drm/i915/display/skl_watermark.c | 176 ++++++++++---------
1 file changed, 92 insertions(+), 84 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c b/drivers/gpu/drm/i915/display/skl_watermark.c
index 2c2371574d6f..b7c92c718c8f 100644
--- a/drivers/gpu/drm/i915/display/skl_watermark.c
+++ b/drivers/gpu/drm/i915/display/skl_watermark.c
@@ -2680,6 +2680,97 @@ static char enast(bool enable)
return enable ? '*' : ' ';
}
+static noinline_for_stack void
+skl_print_plane_changes(struct intel_display *display,
+ struct intel_plane *plane,
+ const struct skl_plane_wm *old_wm,
+ const struct skl_plane_wm *new_wm)
+{
+ drm_dbg_kms(display->drm,
+ "[PLANE:%d:%s] level %cwm0,%cwm1,%cwm2,%cwm3,%cwm4,%cwm5,%cwm6,%cwm7,%ctwm,%cswm,%cstwm"
+ " -> %cwm0,%cwm1,%cwm2,%cwm3,%cwm4,%cwm5,%cwm6,%cwm7,%ctwm,%cswm,%cstwm\n",
+ plane->base.base.id, plane->base.name,
+ enast(old_wm->wm[0].enable), enast(old_wm->wm[1].enable),
+ enast(old_wm->wm[2].enable), enast(old_wm->wm[3].enable),
+ enast(old_wm->wm[4].enable), enast(old_wm->wm[5].enable),
+ enast(old_wm->wm[6].enable), enast(old_wm->wm[7].enable),
+ enast(old_wm->trans_wm.enable),
+ enast(old_wm->sagv.wm0.enable),
+ enast(old_wm->sagv.trans_wm.enable),
+ enast(new_wm->wm[0].enable), enast(new_wm->wm[1].enable),
+ enast(new_wm->wm[2].enable), enast(new_wm->wm[3].enable),
+ enast(new_wm->wm[4].enable), enast(new_wm->wm[5].enable),
+ enast(new_wm->wm[6].enable), enast(new_wm->wm[7].enable),
+ enast(new_wm->trans_wm.enable),
+ enast(new_wm->sagv.wm0.enable),
+ enast(new_wm->sagv.trans_wm.enable));
+
+ drm_dbg_kms(display->drm,
+ "[PLANE:%d:%s] lines %c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%4d"
+ " -> %c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%4d\n",
+ plane->base.base.id, plane->base.name,
+ enast(old_wm->wm[0].ignore_lines), old_wm->wm[0].lines,
+ enast(old_wm->wm[1].ignore_lines), old_wm->wm[1].lines,
+ enast(old_wm->wm[2].ignore_lines), old_wm->wm[2].lines,
+ enast(old_wm->wm[3].ignore_lines), old_wm->wm[3].lines,
+ enast(old_wm->wm[4].ignore_lines), old_wm->wm[4].lines,
+ enast(old_wm->wm[5].ignore_lines), old_wm->wm[5].lines,
+ enast(old_wm->wm[6].ignore_lines), old_wm->wm[6].lines,
+ enast(old_wm->wm[7].ignore_lines), old_wm->wm[7].lines,
+ enast(old_wm->trans_wm.ignore_lines), old_wm->trans_wm.lines,
+ enast(old_wm->sagv.wm0.ignore_lines), old_wm->sagv.wm0.lines,
+ enast(old_wm->sagv.trans_wm.ignore_lines), old_wm->sagv.trans_wm.lines,
+ enast(new_wm->wm[0].ignore_lines), new_wm->wm[0].lines,
+ enast(new_wm->wm[1].ignore_lines), new_wm->wm[1].lines,
+ enast(new_wm->wm[2].ignore_lines), new_wm->wm[2].lines,
+ enast(new_wm->wm[3].ignore_lines), new_wm->wm[3].lines,
+ enast(new_wm->wm[4].ignore_lines), new_wm->wm[4].lines,
+ enast(new_wm->wm[5].ignore_lines), new_wm->wm[5].lines,
+ enast(new_wm->wm[6].ignore_lines), new_wm->wm[6].lines,
+ enast(new_wm->wm[7].ignore_lines), new_wm->wm[7].lines,
+ enast(new_wm->trans_wm.ignore_lines), new_wm->trans_wm.lines,
+ enast(new_wm->sagv.wm0.ignore_lines), new_wm->sagv.wm0.lines,
+ enast(new_wm->sagv.trans_wm.ignore_lines), new_wm->sagv.trans_wm.lines);
+
+ drm_dbg_kms(display->drm,
+ "[PLANE:%d:%s] blocks %4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%5d"
+ " -> %4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%5d\n",
+ plane->base.base.id, plane->base.name,
+ old_wm->wm[0].blocks, old_wm->wm[1].blocks,
+ old_wm->wm[2].blocks, old_wm->wm[3].blocks,
+ old_wm->wm[4].blocks, old_wm->wm[5].blocks,
+ old_wm->wm[6].blocks, old_wm->wm[7].blocks,
+ old_wm->trans_wm.blocks,
+ old_wm->sagv.wm0.blocks,
+ old_wm->sagv.trans_wm.blocks,
+ new_wm->wm[0].blocks, new_wm->wm[1].blocks,
+ new_wm->wm[2].blocks, new_wm->wm[3].blocks,
+ new_wm->wm[4].blocks, new_wm->wm[5].blocks,
+ new_wm->wm[6].blocks, new_wm->wm[7].blocks,
+ new_wm->trans_wm.blocks,
+ new_wm->sagv.wm0.blocks,
+ new_wm->sagv.trans_wm.blocks);
+
+ drm_dbg_kms(display->drm,
+ "[PLANE:%d:%s] min_ddb %4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%5d"
+ " -> %4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%5d\n",
+ plane->base.base.id, plane->base.name,
+ old_wm->wm[0].min_ddb_alloc, old_wm->wm[1].min_ddb_alloc,
+ old_wm->wm[2].min_ddb_alloc, old_wm->wm[3].min_ddb_alloc,
+ old_wm->wm[4].min_ddb_alloc, old_wm->wm[5].min_ddb_alloc,
+ old_wm->wm[6].min_ddb_alloc, old_wm->wm[7].min_ddb_alloc,
+ old_wm->trans_wm.min_ddb_alloc,
+ old_wm->sagv.wm0.min_ddb_alloc,
+ old_wm->sagv.trans_wm.min_ddb_alloc,
+ new_wm->wm[0].min_ddb_alloc, new_wm->wm[1].min_ddb_alloc,
+ new_wm->wm[2].min_ddb_alloc, new_wm->wm[3].min_ddb_alloc,
+ new_wm->wm[4].min_ddb_alloc, new_wm->wm[5].min_ddb_alloc,
+ new_wm->wm[6].min_ddb_alloc, new_wm->wm[7].min_ddb_alloc,
+ new_wm->trans_wm.min_ddb_alloc,
+ new_wm->sagv.wm0.min_ddb_alloc,
+ new_wm->sagv.trans_wm.min_ddb_alloc);
+}
+
static void
skl_print_wm_changes(struct intel_atomic_state *state)
{
@@ -2709,7 +2800,6 @@ skl_print_wm_changes(struct intel_atomic_state *state)
if (skl_ddb_entry_equal(old, new))
continue;
-
drm_dbg_kms(display->drm,
"[PLANE:%d:%s] ddb (%4d - %4d) -> (%4d - %4d), size %4d -> %4d\n",
plane->base.base.id, plane->base.name,
@@ -2727,89 +2817,7 @@ skl_print_wm_changes(struct intel_atomic_state *state)
if (skl_plane_wm_equals(display, old_wm, new_wm))
continue;
- drm_dbg_kms(display->drm,
- "[PLANE:%d:%s] level %cwm0,%cwm1,%cwm2,%cwm3,%cwm4,%cwm5,%cwm6,%cwm7,%ctwm,%cswm,%cstwm"
- " -> %cwm0,%cwm1,%cwm2,%cwm3,%cwm4,%cwm5,%cwm6,%cwm7,%ctwm,%cswm,%cstwm\n",
- plane->base.base.id, plane->base.name,
- enast(old_wm->wm[0].enable), enast(old_wm->wm[1].enable),
- enast(old_wm->wm[2].enable), enast(old_wm->wm[3].enable),
- enast(old_wm->wm[4].enable), enast(old_wm->wm[5].enable),
- enast(old_wm->wm[6].enable), enast(old_wm->wm[7].enable),
- enast(old_wm->trans_wm.enable),
- enast(old_wm->sagv.wm0.enable),
- enast(old_wm->sagv.trans_wm.enable),
- enast(new_wm->wm[0].enable), enast(new_wm->wm[1].enable),
- enast(new_wm->wm[2].enable), enast(new_wm->wm[3].enable),
- enast(new_wm->wm[4].enable), enast(new_wm->wm[5].enable),
- enast(new_wm->wm[6].enable), enast(new_wm->wm[7].enable),
- enast(new_wm->trans_wm.enable),
- enast(new_wm->sagv.wm0.enable),
- enast(new_wm->sagv.trans_wm.enable));
-
- drm_dbg_kms(display->drm,
- "[PLANE:%d:%s] lines %c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%4d"
- " -> %c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%3d,%c%4d\n",
- plane->base.base.id, plane->base.name,
- enast(old_wm->wm[0].ignore_lines), old_wm->wm[0].lines,
- enast(old_wm->wm[1].ignore_lines), old_wm->wm[1].lines,
- enast(old_wm->wm[2].ignore_lines), old_wm->wm[2].lines,
- enast(old_wm->wm[3].ignore_lines), old_wm->wm[3].lines,
- enast(old_wm->wm[4].ignore_lines), old_wm->wm[4].lines,
- enast(old_wm->wm[5].ignore_lines), old_wm->wm[5].lines,
- enast(old_wm->wm[6].ignore_lines), old_wm->wm[6].lines,
- enast(old_wm->wm[7].ignore_lines), old_wm->wm[7].lines,
- enast(old_wm->trans_wm.ignore_lines), old_wm->trans_wm.lines,
- enast(old_wm->sagv.wm0.ignore_lines), old_wm->sagv.wm0.lines,
- enast(old_wm->sagv.trans_wm.ignore_lines), old_wm->sagv.trans_wm.lines,
- enast(new_wm->wm[0].ignore_lines), new_wm->wm[0].lines,
- enast(new_wm->wm[1].ignore_lines), new_wm->wm[1].lines,
- enast(new_wm->wm[2].ignore_lines), new_wm->wm[2].lines,
- enast(new_wm->wm[3].ignore_lines), new_wm->wm[3].lines,
- enast(new_wm->wm[4].ignore_lines), new_wm->wm[4].lines,
- enast(new_wm->wm[5].ignore_lines), new_wm->wm[5].lines,
- enast(new_wm->wm[6].ignore_lines), new_wm->wm[6].lines,
- enast(new_wm->wm[7].ignore_lines), new_wm->wm[7].lines,
- enast(new_wm->trans_wm.ignore_lines), new_wm->trans_wm.lines,
- enast(new_wm->sagv.wm0.ignore_lines), new_wm->sagv.wm0.lines,
- enast(new_wm->sagv.trans_wm.ignore_lines), new_wm->sagv.trans_wm.lines);
-
- drm_dbg_kms(display->drm,
- "[PLANE:%d:%s] blocks %4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%5d"
- " -> %4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%5d\n",
- plane->base.base.id, plane->base.name,
- old_wm->wm[0].blocks, old_wm->wm[1].blocks,
- old_wm->wm[2].blocks, old_wm->wm[3].blocks,
- old_wm->wm[4].blocks, old_wm->wm[5].blocks,
- old_wm->wm[6].blocks, old_wm->wm[7].blocks,
- old_wm->trans_wm.blocks,
- old_wm->sagv.wm0.blocks,
- old_wm->sagv.trans_wm.blocks,
- new_wm->wm[0].blocks, new_wm->wm[1].blocks,
- new_wm->wm[2].blocks, new_wm->wm[3].blocks,
- new_wm->wm[4].blocks, new_wm->wm[5].blocks,
- new_wm->wm[6].blocks, new_wm->wm[7].blocks,
- new_wm->trans_wm.blocks,
- new_wm->sagv.wm0.blocks,
- new_wm->sagv.trans_wm.blocks);
-
- drm_dbg_kms(display->drm,
- "[PLANE:%d:%s] min_ddb %4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%5d"
- " -> %4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%4d,%5d\n",
- plane->base.base.id, plane->base.name,
- old_wm->wm[0].min_ddb_alloc, old_wm->wm[1].min_ddb_alloc,
- old_wm->wm[2].min_ddb_alloc, old_wm->wm[3].min_ddb_alloc,
- old_wm->wm[4].min_ddb_alloc, old_wm->wm[5].min_ddb_alloc,
- old_wm->wm[6].min_ddb_alloc, old_wm->wm[7].min_ddb_alloc,
- old_wm->trans_wm.min_ddb_alloc,
- old_wm->sagv.wm0.min_ddb_alloc,
- old_wm->sagv.trans_wm.min_ddb_alloc,
- new_wm->wm[0].min_ddb_alloc, new_wm->wm[1].min_ddb_alloc,
- new_wm->wm[2].min_ddb_alloc, new_wm->wm[3].min_ddb_alloc,
- new_wm->wm[4].min_ddb_alloc, new_wm->wm[5].min_ddb_alloc,
- new_wm->wm[6].min_ddb_alloc, new_wm->wm[7].min_ddb_alloc,
- new_wm->trans_wm.min_ddb_alloc,
- new_wm->sagv.wm0.min_ddb_alloc,
- new_wm->sagv.trans_wm.min_ddb_alloc);
+ skl_print_plane_changes(display, plane, old_wm, new_wm);
}
}
}
--
2.39.5
next reply other threads:[~2025-06-20 11:38 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-06-20 11:37 Arnd Bergmann [this message]
2025-06-20 11:43 ` ✗ CI.checkpatch: warning for drm/i915/wm: reduce stack usage in skl_print_wm_changes() Patchwork
2025-06-20 11:44 ` ✓ CI.KUnit: success " Patchwork
2025-06-20 21:33 ` ✗ Xe.CI.Full: failure " Patchwork
2025-06-24 21:16 ` [PATCH] " Rodrigo Vivi
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