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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/strlen.S
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/strlen.S')
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1 files changed, 59 insertions, 0 deletions
diff --git a/arch/alpha/lib/strlen.S b/arch/alpha/lib/strlen.S
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * strlen.S (c) 1995 David Mosberger (davidm@cs.arizona.edu)
+ *
+ * Finds length of a 0-terminated string. Optimized for the
+ * Alpha architecture:
+ *
+ * - memory accessed as aligned quadwords only
+ * - uses bcmpge to compare 8 bytes in parallel
+ * - does binary search to find 0 byte in last
+ * quadword (HAKMEM needed 12 instructions to
+ * do this instead of the 9 instructions that
+ * binary search needs).
+ */
+#include <linux/export.h>
+ .set noreorder
+ .set noat
+
+ .align 3
+
+ .globl strlen
+ .ent strlen
+
+strlen:
+ ldq_u $1, 0($16) # load first quadword ($16 may be misaligned)
+ lda $2, -1($31)
+ insqh $2, $16, $2
+ andnot $16, 7, $0
+ or $2, $1, $1
+ cmpbge $31, $1, $2 # $2 <- bitmask: bit i == 1 <==> i-th byte == 0
+ bne $2, found
+
+loop: ldq $1, 8($0)
+ addq $0, 8, $0 # addr += 8
+ nop # helps dual issue last two insns
+ cmpbge $31, $1, $2
+ beq $2, loop
+
+found: blbs $2, done # make aligned case fast
+ negq $2, $3
+ and $2, $3, $2
+
+ and $2, 0x0f, $1
+ addq $0, 4, $3
+ cmoveq $1, $3, $0
+
+ and $2, 0x33, $1
+ addq $0, 2, $3
+ cmoveq $1, $3, $0
+
+ and $2, 0x55, $1
+ addq $0, 1, $3
+ cmoveq $1, $3, $0
+
+done: subq $0, $16, $0
+ ret $31, ($26)
+
+ .end strlen
+ EXPORT_SYMBOL(strlen)