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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/alpha/lib/ev67-strlen.S
downloadlinux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.tar.gz
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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/alpha/lib/ev67-strlen.S')
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1 files changed, 51 insertions, 0 deletions
diff --git a/arch/alpha/lib/ev67-strlen.S b/arch/alpha/lib/ev67-strlen.S
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * arch/alpha/lib/ev67-strlen.S
+ * 21264 version by Rick Gorton <rick.gorton@alpha-processor.com>
+ *
+ * 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
+ *
+ * Much of the information about 21264 scheduling/coding comes from:
+ * Compiler Writer's Guide for the Alpha 21264
+ * abbreviated as 'CWG' in other comments here
+ * ftp.digital.com/pub/Digital/info/semiconductor/literature/dsc-library.html
+ * Scheduling notation:
+ * E - either cluster
+ * U - upper subcluster; U0 - subcluster U0; U1 - subcluster U1
+ * L - lower subcluster; L0 - subcluster L0; L1 - subcluster L1
+ */
+#include <linux/export.h>
+ .set noreorder
+ .set noat
+
+ .globl strlen
+ .ent strlen
+ .align 4
+strlen:
+ ldq_u $1, 0($16) # L : load first quadword ($16 may be misaligned)
+ lda $2, -1($31) # E :
+ insqh $2, $16, $2 # U :
+ andnot $16, 7, $0 # E :
+
+ or $2, $1, $1 # E :
+ cmpbge $31, $1, $2 # E : $2 <- bitmask: bit i == 1 <==> i-th byte == 0
+ nop # E :
+ bne $2, $found # U :
+
+$loop: ldq $1, 8($0) # L :
+ addq $0, 8, $0 # E : addr += 8
+ cmpbge $31, $1, $2 # E :
+ beq $2, $loop # U :
+
+$found:
+ cttz $2, $3 # U0 :
+ addq $0, $3, $0 # E :
+ subq $0, $16, $0 # E :
+ ret $31, ($26) # L0 :
+
+ .end strlen
+ EXPORT_SYMBOL(strlen)