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-rw-r--r--include/linux/clk-provider.h1
-rw-r--r--include/linux/hash.h20
-rw-r--r--include/linux/swap.h4
3 files changed, 23 insertions, 2 deletions
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 1143e3855..408a60dca 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -385,6 +385,7 @@ struct clk_divider {
#define CLK_DIVIDER_MAX_AT_ZERO BIT(6)
extern const struct clk_ops clk_divider_ops;
+extern const struct clk_ops clk_divider_ro_ops;
unsigned long divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate,
unsigned int val, const struct clk_div_table *table,
diff --git a/include/linux/hash.h b/include/linux/hash.h
index 1afde47e1..79c52fa81 100644
--- a/include/linux/hash.h
+++ b/include/linux/hash.h
@@ -32,12 +32,28 @@
#error Wordsize not 32 or 64
#endif
+/*
+ * The above primes are actively bad for hashing, since they are
+ * too sparse. The 32-bit one is mostly ok, the 64-bit one causes
+ * real problems. Besides, the "prime" part is pointless for the
+ * multiplicative hash.
+ *
+ * Although a random odd number will do, it turns out that the golden
+ * ratio phi = (sqrt(5)-1)/2, or its negative, has particularly nice
+ * properties.
+ *
+ * These are the negative, (1 - phi) = (phi^2) = (3 - sqrt(5))/2.
+ * (See Knuth vol 3, section 6.4, exercise 9.)
+ */
+#define GOLDEN_RATIO_32 0x61C88647
+#define GOLDEN_RATIO_64 0x61C8864680B583EBull
+
static __always_inline u64 hash_64(u64 val, unsigned int bits)
{
u64 hash = val;
-#if defined(CONFIG_ARCH_HAS_FAST_MULTIPLIER) && BITS_PER_LONG == 64
- hash = hash * GOLDEN_RATIO_PRIME_64;
+#if BITS_PER_LONG == 64
+ hash = hash * GOLDEN_RATIO_64;
#else
/* Sigh, gcc can't optimise this alone like it does for 32 bits. */
u64 n = hash;
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 44324f10f..67f65075a 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -540,6 +540,10 @@ static inline swp_entry_t get_swap_page(void)
#ifdef CONFIG_MEMCG
static inline int mem_cgroup_swappiness(struct mem_cgroup *memcg)
{
+ /* Cgroup2 doesn't have per-cgroup swappiness */
+ if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
+ return vm_swappiness;
+
/* root ? */
if (mem_cgroup_disabled() || !memcg->css.parent)
return vm_swappiness;