Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEADgrafted

Changes:

Make expedited grace periods expedite normal RCU callbacks

Miscellaneous fixes:
 * Improve diagnostic output with character task states.
 * Mark accesses to inform KCSAN of concurrency design.
 * Move from kmalloc() to kmalloc_obj().
 * Documentation updates.
 * Improve handling of RCU deferred quiescent states.
 * Clean up unused function arguments and structure fields.
 * Reduce show_rcu_gp_kthreads() stack space.

Tasks RCU updates:
 * Clean up after SRCU re-implementation of Tasks Trace RCU.
 * Mark accesses to inform KCSAN of concurrency design.
 * Add ->lazy_timer status to diagnostic output.
 * Remove an unnecessary memory barrier.
 * Fix a data race, courtesy of KCSAN.
 * Documentation updates.
 * Convert cond_resched_tasks_rcu_qs() from macro to static inline
   function.

SRCU updates:
 * Add Rust helpers for SRCU.
 * Avoid losing queued work at cleanup_srcu_struct() time.

Torture-test updates:
 * Preparation work for immediate RCU priority deboosting.
 * Test RCU readers from real interrupt handlers (as opposed to softirq).
 * Simplify code through use of cpumask_next_wrap().
 * Improve diagnostic output with character task states.
 * Add rcutorture.nwriters parameter to allow lightweight stall testing,
   and rcutorture.stall_only to make doing so easier.
 * Test an RCU Tasks Trace grace period implying an RCU grace period.
 * Make RCU Tasks Trace torturing track reader batches.
 * Fix a data race, courtesy of KCSAN.
 * Plug a shuffle_tmp_mask memory leak on kthread spawn failure.

1 files changed, 274 insertions, 0 deletions

diff --git a/include/drm/drm_rect.h b/include/drm/drm_rect.h
new file mode 100644
index 000000000..46f09cf68
--- /dev/null
+++ b/include/drm/drm_rect.h
@@ -0,0 +1,274 @@
+/*
+ * Copyright (C) 2011-2013 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef DRM_RECT_H
+#define DRM_RECT_H
+
+#include <linux/types.h>
+
+/**
+ * DOC: rect utils
+ *
+ * Utility functions to help manage rectangular areas for
+ * clipping, scaling, etc. calculations.
+ */
+
+/**
+ * struct drm_rect - two dimensional rectangle
+ * @x1: horizontal starting coordinate (inclusive)
+ * @x2: horizontal ending coordinate (exclusive)
+ * @y1: vertical starting coordinate (inclusive)
+ * @y2: vertical ending coordinate (exclusive)
+ *
+ * Note that this must match the layout of struct drm_mode_rect or the damage
+ * helpers like drm_atomic_helper_damage_iter_init() break.
+ */
+struct drm_rect {
+	int x1, y1, x2, y2;
+};
+
+/**
+ * DRM_RECT_INIT - initialize a rectangle from x/y/w/h
+ * @x: x coordinate
+ * @y: y coordinate
+ * @w: width
+ * @h: height
+ *
+ * RETURNS:
+ * A new rectangle of the specified size.
+ */
+#define DRM_RECT_INIT(x, y, w, h) ((struct drm_rect){ \
+		.x1 = (x), \
+		.y1 = (y), \
+		.x2 = (x) + (w), \
+		.y2 = (y) + (h) })
+
+/**
+ * DRM_RECT_FMT - printf string for &struct drm_rect
+ */
+#define DRM_RECT_FMT    "%dx%d%+d%+d"
+/**
+ * DRM_RECT_ARG - printf arguments for &struct drm_rect
+ * @r: rectangle struct
+ */
+#define DRM_RECT_ARG(r) drm_rect_width(r), drm_rect_height(r), (r)->x1, (r)->y1
+
+/**
+ * DRM_RECT_FP_FMT - printf string for &struct drm_rect in 16.16 fixed point
+ */
+#define DRM_RECT_FP_FMT "%d.%06ux%d.%06u%+d.%06u%+d.%06u"
+/**
+ * DRM_RECT_FP_ARG - printf arguments for &struct drm_rect in 16.16 fixed point
+ * @r: rectangle struct
+ *
+ * This is useful for e.g. printing plane source rectangles, which are in 16.16
+ * fixed point.
+ */
+#define DRM_RECT_FP_ARG(r) \
+		drm_rect_width(r) >> 16, ((drm_rect_width(r) & 0xffff) * 15625) >> 10, \
+		drm_rect_height(r) >> 16, ((drm_rect_height(r) & 0xffff) * 15625) >> 10, \
+		(r)->x1 >> 16, (((r)->x1 & 0xffff) * 15625) >> 10, \
+		(r)->y1 >> 16, (((r)->y1 & 0xffff) * 15625) >> 10
+
+/**
+ * drm_rect_init - initialize the rectangle from x/y/w/h
+ * @r: rectangle
+ * @x: x coordinate
+ * @y: y coordinate
+ * @width: width
+ * @height: height
+ */
+static inline void drm_rect_init(struct drm_rect *r, int x, int y,
+				 int width, int height)
+{
+	r->x1 = x;
+	r->y1 = y;
+	r->x2 = x + width;
+	r->y2 = y + height;
+}
+
+/**
+ * drm_rect_adjust_size - adjust the size of the rectangle
+ * @r: rectangle to be adjusted
+ * @dw: horizontal adjustment
+ * @dh: vertical adjustment
+ *
+ * Change the size of rectangle @r by @dw in the horizontal direction,
+ * and by @dh in the vertical direction, while keeping the center
+ * of @r stationary.
+ *
+ * Positive @dw and @dh increase the size, negative values decrease it.
+ */
+static inline void drm_rect_adjust_size(struct drm_rect *r, int dw, int dh)
+{
+	r->x1 -= dw >> 1;
+	r->y1 -= dh >> 1;
+	r->x2 += (dw + 1) >> 1;
+	r->y2 += (dh + 1) >> 1;
+}
+
+/**
+ * drm_rect_translate - translate the rectangle
+ * @r: rectangle to be translated
+ * @dx: horizontal translation
+ * @dy: vertical translation
+ *
+ * Move rectangle @r by @dx in the horizontal direction,
+ * and by @dy in the vertical direction.
+ */
+static inline void drm_rect_translate(struct drm_rect *r, int dx, int dy)
+{
+	r->x1 += dx;
+	r->y1 += dy;
+	r->x2 += dx;
+	r->y2 += dy;
+}
+
+/**
+ * drm_rect_translate_to - translate the rectangle to an absolute position
+ * @r: rectangle to be translated
+ * @x: horizontal position
+ * @y: vertical position
+ *
+ * Move rectangle @r to @x in the horizontal direction,
+ * and to @y in the vertical direction.
+ */
+static inline void drm_rect_translate_to(struct drm_rect *r, int x, int y)
+{
+	drm_rect_translate(r, x - r->x1, y - r->y1);
+}
+
+/**
+ * drm_rect_downscale - downscale a rectangle
+ * @r: rectangle to be downscaled
+ * @horz: horizontal downscale factor
+ * @vert: vertical downscale factor
+ *
+ * Divide the coordinates of rectangle @r by @horz and @vert.
+ */
+static inline void drm_rect_downscale(struct drm_rect *r, int horz, int vert)
+{
+	r->x1 /= horz;
+	r->y1 /= vert;
+	r->x2 /= horz;
+	r->y2 /= vert;
+}
+
+/**
+ * drm_rect_width - determine the rectangle width
+ * @r: rectangle whose width is returned
+ *
+ * RETURNS:
+ * The width of the rectangle.
+ */
+static inline int drm_rect_width(const struct drm_rect *r)
+{
+	return r->x2 - r->x1;
+}
+
+/**
+ * drm_rect_height - determine the rectangle height
+ * @r: rectangle whose height is returned
+ *
+ * RETURNS:
+ * The height of the rectangle.
+ */
+static inline int drm_rect_height(const struct drm_rect *r)
+{
+	return r->y2 - r->y1;
+}
+
+/**
+ * drm_rect_visible - determine if the rectangle is visible
+ * @r: rectangle whose visibility is returned
+ *
+ * RETURNS:
+ * %true if the rectangle is visible, %false otherwise.
+ */
+static inline bool drm_rect_visible(const struct drm_rect *r)
+{
+	return drm_rect_width(r) > 0 && drm_rect_height(r) > 0;
+}
+
+/**
+ * drm_rect_equals - determine if two rectangles are equal
+ * @r1: first rectangle
+ * @r2: second rectangle
+ *
+ * RETURNS:
+ * %true if the rectangles are equal, %false otherwise.
+ */
+static inline bool drm_rect_equals(const struct drm_rect *r1,
+				   const struct drm_rect *r2)
+{
+	return r1->x1 == r2->x1 && r1->x2 == r2->x2 &&
+		r1->y1 == r2->y1 && r1->y2 == r2->y2;
+}
+
+/**
+ * drm_rect_fp_to_int - Convert a rect in 16.16 fixed point form to int form.
+ * @dst: rect to be stored the converted value
+ * @src: rect in 16.16 fixed point form
+ */
+static inline void drm_rect_fp_to_int(struct drm_rect *dst,
+				      const struct drm_rect *src)
+{
+	drm_rect_init(dst, src->x1 >> 16, src->y1 >> 16,
+		      drm_rect_width(src) >> 16,
+		      drm_rect_height(src) >> 16);
+}
+
+/**
+ * drm_rect_overlap - Check if two rectangles overlap
+ * @a: first rectangle
+ * @b: second rectangle
+ *
+ * RETURNS:
+ * %true if the rectangles overlap, %false otherwise.
+ */
+static inline bool drm_rect_overlap(const struct drm_rect *a,
+				    const struct drm_rect *b)
+{
+	return (a->x2 > b->x1 && b->x2 > a->x1 &&
+		a->y2 > b->y1 && b->y2 > a->y1);
+}
+
+bool drm_rect_intersect(struct drm_rect *r, const struct drm_rect *clip);
+bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst,
+			  const struct drm_rect *clip);
+int drm_rect_calc_hscale(const struct drm_rect *src,
+			 const struct drm_rect *dst,
+			 int min_hscale, int max_hscale);
+int drm_rect_calc_vscale(const struct drm_rect *src,
+			 const struct drm_rect *dst,
+			 int min_vscale, int max_vscale);
+void drm_rect_debug_print(const char *prefix,
+			  const struct drm_rect *r, bool fixed_point);
+void drm_rect_rotate(struct drm_rect *r,
+		     int width, int height,
+		     unsigned int rotation);
+void drm_rect_rotate_inv(struct drm_rect *r,
+			 int width, int height,
+			 unsigned int rotation);
+
+#endif