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authorBreno Leitao <leitao@debian.org>2026-08-05 07:52:36 -0700
committerTejun Heo <tj@kernel.org>2026-08-10 11:47:20 -1000
commita5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656 (patch)
tree39f5b258386e1127d253d293194e9a2991bf3c34 /arch/openrisc/lib/memcpy.c
downloadlinux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.tar.gz
linux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.zip
workqueue: skip the node_nr_active update for non-unbound workqueuesgrafted
apply_wqattrs_commit() updates node_nr_active->max unconditionally. wq->node_nr_active[] is only allocated for unbound workqueues, so guard the call before per-cpu workqueues start using this path. No functional change: only unbound workqueues reach apply_wqattrs_*() today. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'arch/openrisc/lib/memcpy.c')
-rw-r--r--arch/openrisc/lib/memcpy.c125
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/openrisc/lib/memcpy.c b/arch/openrisc/lib/memcpy.c
new file mode 100644
index 000000000..e2af9b510
--- /dev/null
+++ b/arch/openrisc/lib/memcpy.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * arch/openrisc/lib/memcpy.c
+ *
+ * Optimized memory copy routines for openrisc. These are mostly copied
+ * from ohter sources but slightly entended based on ideas discuassed in
+ * #openrisc.
+ *
+ * The word unroll implementation is an extension to the arm byte
+ * unrolled implementation, but using word copies (if things are
+ * properly aligned)
+ *
+ * The great arm loop unroll algorithm can be found at:
+ * arch/arm/boot/compressed/string.c
+ */
+
+#include <linux/export.h>
+
+#include <linux/string.h>
+
+#ifdef CONFIG_OR1K_1200
+/*
+ * Do memcpy with word copies and loop unrolling. This gives the
+ * best performance on the OR1200 and MOR1KX archirectures
+ */
+void *memcpy(void *dest, __const void *src, __kernel_size_t n)
+{
+ int i = 0;
+ unsigned char *d, *s;
+ uint32_t *dest_w = (uint32_t *)dest, *src_w = (uint32_t *)src;
+
+ /* If both source and dest are word aligned copy words */
+ if (!((unsigned int)dest_w & 3) && !((unsigned int)src_w & 3)) {
+ /* Copy 32 bytes per loop */
+ for (i = n >> 5; i > 0; i--) {
+ *dest_w++ = *src_w++;
+ *dest_w++ = *src_w++;
+ *dest_w++ = *src_w++;
+ *dest_w++ = *src_w++;
+ *dest_w++ = *src_w++;
+ *dest_w++ = *src_w++;
+ *dest_w++ = *src_w++;
+ *dest_w++ = *src_w++;
+ }
+
+ if (n & 1 << 4) {
+ *dest_w++ = *src_w++;
+ *dest_w++ = *src_w++;
+ *dest_w++ = *src_w++;
+ *dest_w++ = *src_w++;
+ }
+
+ if (n & 1 << 3) {
+ *dest_w++ = *src_w++;
+ *dest_w++ = *src_w++;
+ }
+
+ if (n & 1 << 2)
+ *dest_w++ = *src_w++;
+
+ d = (unsigned char *)dest_w;
+ s = (unsigned char *)src_w;
+
+ } else {
+ d = (unsigned char *)dest_w;
+ s = (unsigned char *)src_w;
+
+ for (i = n >> 3; i > 0; i--) {
+ *d++ = *s++;
+ *d++ = *s++;
+ *d++ = *s++;
+ *d++ = *s++;
+ *d++ = *s++;
+ *d++ = *s++;
+ *d++ = *s++;
+ *d++ = *s++;
+ }
+
+ if (n & 1 << 2) {
+ *d++ = *s++;
+ *d++ = *s++;
+ *d++ = *s++;
+ *d++ = *s++;
+ }
+ }
+
+ if (n & 1 << 1) {
+ *d++ = *s++;
+ *d++ = *s++;
+ }
+
+ if (n & 1)
+ *d++ = *s++;
+
+ return dest;
+}
+#else
+/*
+ * Use word copies but no loop unrolling as we cannot assume there
+ * will be benefits on the archirecture
+ */
+void *memcpy(void *dest, __const void *src, __kernel_size_t n)
+{
+ unsigned char *d, *s;
+ uint32_t *dest_w = (uint32_t *)dest, *src_w = (uint32_t *)src;
+
+ /* If both source and dest are word aligned copy words */
+ if (!((unsigned int)dest_w & 3) && !((unsigned int)src_w & 3)) {
+ for (; n >= 4; n -= 4)
+ *dest_w++ = *src_w++;
+ }
+
+ d = (unsigned char *)dest_w;
+ s = (unsigned char *)src_w;
+
+ /* For remaining or if not aligned, copy bytes */
+ for (; n >= 1; n -= 1)
+ *d++ = *s++;
+
+ return dest;
+
+}
+#endif
+
+EXPORT_SYMBOL(memcpy);