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authorJoel Fernandes <joelagnelf@nvidia.com>2026-07-18 13:15:36 -0400
committerPaul E. McKenney <paulmck@kernel.org>2026-07-23 10:39:57 -0700
commit34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch)
tree7629759c1ec7148b95bc8ab3080df20a5ecd2273 /arch/alpha/lib/memcpy.c
downloadlinux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz
linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'arch/alpha/lib/memcpy.c')
-rw-r--r--arch/alpha/lib/memcpy.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/alpha/lib/memcpy.c b/arch/alpha/lib/memcpy.c
new file mode 100644
index 000000000..78b6850a9
--- /dev/null
+++ b/arch/alpha/lib/memcpy.c
@@ -0,0 +1,166 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/arch/alpha/lib/memcpy.c
+ *
+ * Copyright (C) 1995 Linus Torvalds
+ */
+
+/*
+ * This is a reasonably optimized memcpy() routine.
+ */
+
+/*
+ * Note that the C code is written to be optimized into good assembly. However,
+ * at this point gcc is unable to sanely compile "if (n >= 0)", resulting in a
+ * explicit compare against 0 (instead of just using the proper "blt reg, xx" or
+ * "bge reg, xx"). I hope alpha-gcc will be fixed to notice this eventually..
+ */
+
+#include <linux/types.h>
+#include <linux/export.h>
+#include <linux/string.h>
+
+/*
+ * This should be done in one go with ldq_u*2/mask/stq_u. Do it
+ * with a macro so that we can fix it up later..
+ */
+#define ALIGN_DEST_TO8_UP(d,s,n) \
+ while (d & 7) { \
+ if (n <= 0) return; \
+ n--; \
+ *(char *) d = *(char *) s; \
+ d++; s++; \
+ }
+#define ALIGN_DEST_TO8_DN(d,s,n) \
+ while (d & 7) { \
+ if (n <= 0) return; \
+ n--; \
+ d--; s--; \
+ *(char *) d = *(char *) s; \
+ }
+
+/*
+ * This should similarly be done with ldq_u*2/mask/stq. The destination
+ * is aligned, but we don't fill in a full quad-word
+ */
+#define DO_REST_UP(d,s,n) \
+ while (n > 0) { \
+ n--; \
+ *(char *) d = *(char *) s; \
+ d++; s++; \
+ }
+#define DO_REST_DN(d,s,n) \
+ while (n > 0) { \
+ n--; \
+ d--; s--; \
+ *(char *) d = *(char *) s; \
+ }
+
+/*
+ * This should be done with ldq/mask/stq. The source and destination are
+ * aligned, but we don't fill in a full quad-word
+ */
+#define DO_REST_ALIGNED_UP(d,s,n) DO_REST_UP(d,s,n)
+#define DO_REST_ALIGNED_DN(d,s,n) DO_REST_DN(d,s,n)
+
+/*
+ * This does unaligned memory copies. We want to avoid storing to
+ * an unaligned address, as that would do a read-modify-write cycle.
+ * We also want to avoid double-reading the unaligned reads.
+ *
+ * Note the ordering to try to avoid load (and address generation) latencies.
+ */
+static inline void __memcpy_unaligned_up (unsigned long d, unsigned long s,
+ long n)
+{
+ ALIGN_DEST_TO8_UP(d,s,n);
+ n -= 8; /* to avoid compare against 8 in the loop */
+ if (n >= 0) {
+ unsigned long low_word, high_word;
+ __asm__("ldq_u %0,%1":"=r" (low_word):"m" (*(unsigned long *) s));
+ do {
+ unsigned long tmp;
+ __asm__("ldq_u %0,%1":"=r" (high_word):"m" (*(unsigned long *)(s+8)));
+ n -= 8;
+ __asm__("extql %1,%2,%0"
+ :"=r" (low_word)
+ :"r" (low_word), "r" (s));
+ __asm__("extqh %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (high_word), "r" (s));
+ s += 8;
+ *(unsigned long *) d = low_word | tmp;
+ d += 8;
+ low_word = high_word;
+ } while (n >= 0);
+ }
+ n += 8;
+ DO_REST_UP(d,s,n);
+}
+
+static inline void __memcpy_unaligned_dn (unsigned long d, unsigned long s,
+ long n)
+{
+ /* I don't understand AXP assembler well enough for this. -Tim */
+ s += n;
+ d += n;
+ while (n--)
+ * (char *) --d = * (char *) --s;
+}
+
+/*
+ * Hmm.. Strange. The __asm__ here is there to make gcc use an integer register
+ * for the load-store. I don't know why, but it would seem that using a floating
+ * point register for the move seems to slow things down (very small difference,
+ * though).
+ *
+ * Note the ordering to try to avoid load (and address generation) latencies.
+ */
+static inline void __memcpy_aligned_up (unsigned long d, unsigned long s,
+ long n)
+{
+ ALIGN_DEST_TO8_UP(d,s,n);
+ n -= 8;
+ while (n >= 0) {
+ unsigned long tmp;
+ __asm__("ldq %0,%1":"=r" (tmp):"m" (*(unsigned long *) s));
+ n -= 8;
+ s += 8;
+ *(unsigned long *) d = tmp;
+ d += 8;
+ }
+ n += 8;
+ DO_REST_ALIGNED_UP(d,s,n);
+}
+static inline void __memcpy_aligned_dn (unsigned long d, unsigned long s,
+ long n)
+{
+ s += n;
+ d += n;
+ ALIGN_DEST_TO8_DN(d,s,n);
+ n -= 8;
+ while (n >= 0) {
+ unsigned long tmp;
+ s -= 8;
+ __asm__("ldq %0,%1":"=r" (tmp):"m" (*(unsigned long *) s));
+ n -= 8;
+ d -= 8;
+ *(unsigned long *) d = tmp;
+ }
+ n += 8;
+ DO_REST_ALIGNED_DN(d,s,n);
+}
+
+#undef memcpy
+
+void * memcpy(void * dest, const void *src, size_t n)
+{
+ if (!(((unsigned long) dest ^ (unsigned long) src) & 7)) {
+ __memcpy_aligned_up ((unsigned long) dest, (unsigned long) src,
+ n);
+ return dest;
+ }
+ __memcpy_unaligned_up ((unsigned long) dest, (unsigned long) src, n);
+ return dest;
+}
+EXPORT_SYMBOL(memcpy);