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authorDapeng Mi <dapeng1.mi@linux.intel.com>2026-09-17 09:52:33 +0800
committerIngo Molnar <mingo@kernel.org>2026-09-22 11:37:46 +0200
commit0102c8c7fdfc4bd700971daff2b94470f4eafae4 (patch)
tree531306c2299f9a269f0a986e29f17ba972180104 /lib/math/int_sqrt.c
downloadlinux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.tar.gz
linux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.zip
perf/x86/intel: Rename DMR offcore_rsp attribute to offmodule_rspgrafted
DMR introduces Offmodule Response events in place of the legacy Offcore Response events, but it still exposes the inherited offcore_rsp PMU attribute for programming the corresponding MSR data. Rename the DMR PMU attribute to offmodule_rsp so the sysfs interface matches the underlying event name and avoids user & tooling confusion. Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://patch.msgid.link/20260917015234.981153-12-dapeng1.mi@linux.intel.com
Diffstat (limited to 'lib/math/int_sqrt.c')
-rw-r--r--lib/math/int_sqrt.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/lib/math/int_sqrt.c b/lib/math/int_sqrt.c
new file mode 100644
index 000000000..a8170bb91
--- /dev/null
+++ b/lib/math/int_sqrt.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2013 Davidlohr Bueso <davidlohr.bueso@hp.com>
+ *
+ * Based on the shift-and-subtract algorithm for computing integer
+ * square root from Guy L. Steele.
+ */
+
+#include <linux/export.h>
+#include <linux/bitops.h>
+#include <linux/limits.h>
+#include <linux/math.h>
+
+/**
+ * int_sqrt - computes the integer square root
+ * @x: integer of which to calculate the sqrt
+ *
+ * Computes: floor(sqrt(x))
+ */
+unsigned long int_sqrt(unsigned long x)
+{
+ unsigned long b, m, y = 0;
+
+ if (x <= 1)
+ return x;
+
+ m = 1UL << (__fls(x) & ~1UL);
+ while (m != 0) {
+ b = y + m;
+ y >>= 1;
+
+ if (x >= b) {
+ x -= b;
+ y += m;
+ }
+ m >>= 2;
+ }
+
+ return y;
+}
+EXPORT_SYMBOL(int_sqrt);
+
+#if BITS_PER_LONG < 64
+/**
+ * int_sqrt64 - strongly typed int_sqrt function when minimum 64 bit input
+ * is expected.
+ * @x: 64bit integer of which to calculate the sqrt
+ */
+u32 int_sqrt64(u64 x)
+{
+ u64 b, m, y = 0;
+
+ if (x <= ULONG_MAX)
+ return int_sqrt((unsigned long) x);
+
+ m = 1ULL << ((fls64(x) - 1) & ~1ULL);
+ while (m != 0) {
+ b = y + m;
+ y >>= 1;
+
+ if (x >= b) {
+ x -= b;
+ y += m;
+ }
+ m >>= 2;
+ }
+
+ return y;
+}
+EXPORT_SYMBOL(int_sqrt64);
+#endif