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, 118 insertions, 0 deletions

diff --git a/scripts/gfp-translate b/scripts/gfp-translate
new file mode 100755
index 000000000..8385ae0d5
--- /dev/null
+++ b/scripts/gfp-translate
@@ -0,0 +1,118 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0-only
+# Translate the bits making up a GFP mask
+# (c) 2009, Mel Gorman <mel@csn.ul.ie>
+SOURCE=
+GFPMASK=none
+
+# Helper function to report failures and exit
+die() {
+	echo ERROR: $@
+	if [ "$TMPFILE" != "" ]; then
+		rm -f $TMPFILE
+	fi
+	exit -1
+}
+
+usage() {
+	echo "usage: gfp-translate [-h] [ --source DIRECTORY ] gfpmask"
+	exit 0
+}
+
+# Parse command-line arguments
+while [ $# -gt 0 ]; do
+	case $1 in
+		--source)
+			SOURCE=$2
+			shift 2
+			;;
+		-h)
+			usage
+			;;
+		--help)
+			usage
+			;;
+		*)
+			GFPMASK=$1
+			shift
+			;;
+	esac
+done
+
+# Guess the kernel source directory if it's not set. Preference is in order of
+# o current directory
+# o /usr/src/linux
+if [ "$SOURCE" = "" ]; then
+	if [ -r "/usr/src/linux/Makefile" ]; then
+		SOURCE=/usr/src/linux
+	fi
+	if [ -r "`pwd`/Makefile" ]; then
+		SOURCE=`pwd`
+	fi
+fi
+
+# Confirm that a source directory exists
+if [ ! -r "$SOURCE/Makefile" ]; then
+	die "Could not locate kernel source directory or it is invalid"
+fi
+
+# Confirm that a GFP mask has been specified
+if [ "$GFPMASK" = "none" ]; then
+	usage
+fi
+
+# Extract GFP flags from the kernel source
+TMPFILE=`mktemp -t gfptranslate-XXXXXX.c` || exit 1
+
+echo Source: $SOURCE
+echo Parsing: $GFPMASK
+
+(
+    cat <<EOF
+#include <stdint.h>
+#include <stdio.h>
+
+// Try to fool compiler.h into not including extra stuff
+#define __ASSEMBLY__	1
+
+#include <generated/autoconf.h>
+#include <linux/gfp_types.h>
+
+static const char *masks[] = {
+EOF
+
+    sed -nEe 's/^[[:space:]]+(___GFP_.*)_BIT,.*$/\1/p' $SOURCE/include/linux/gfp_types.h |
+	while read b; do
+	    cat <<EOF
+#if defined($b) && ($b > 0)
+	[${b}_BIT]	= "$b",
+#endif
+EOF
+	done
+
+    cat <<EOF
+};
+
+int main(int argc, char *argv[])
+{
+	unsigned long long mask = $GFPMASK;
+
+	for (int i = 0; i < sizeof(mask) * 8; i++) {
+		unsigned long long bit = 1ULL << i;
+		if (mask & bit)
+			printf("\t%-25s0x%llx\n",
+			       (i < ___GFP_LAST_BIT && masks[i]) ?
+					masks[i] : "*** INVALID ***",
+			       bit);
+	}
+
+	return 0;
+}
+EOF
+) > $TMPFILE
+
+${CC:-gcc} -Wall -o ${TMPFILE}.bin -I $SOURCE/include $TMPFILE && ${TMPFILE}.bin
+
+rm -f $TMPFILE ${TMPFILE}.bin
+
+exit 0