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authorSang-Heon Jeon <ekffu200098@gmail.com>2026-08-24 01:18:14 +0900
committerJulia Lawall <Julia.Lawall@inria.fr>2026-08-23 22:12:11 +0200
commit2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c (patch)
treedcc4da1d99f17541c5590ac63c77da4bf372a4ab /samples/bpf/hash_func01.h
downloadlinux-stable-2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c.tar.gz
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coccinelle: alloc_cast: drop removed allocatorsgrafted
- pci_alloc_consistent() and pci_zalloc_consistent() were removed by commit 7968778914e5 ("PCI: Remove the deprecated "pci-dma-compat.h" API") - kmem_alloc() was removed by commit f078d4ea8276 ("xfs: convert kmem_alloc() to kmalloc()") - kmem_zalloc() was removed by commit 10634530f7ba ("xfs: convert kmem_zalloc() to kzalloc()") - kmem_zone_alloc() and kmem_zone_zalloc() were removed by commit bae633a4a283 ("xfs: remove xfs_zone_{alloc,zalloc} helpers") So drop them from the rules. No functional change. Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com> Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Diffstat (limited to 'samples/bpf/hash_func01.h')
-rw-r--r--samples/bpf/hash_func01.h55
1 files changed, 55 insertions, 0 deletions
diff --git a/samples/bpf/hash_func01.h b/samples/bpf/hash_func01.h
new file mode 100644
index 000000000..38255812e
--- /dev/null
+++ b/samples/bpf/hash_func01.h
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: LGPL-2.1
+ *
+ * Based on Paul Hsieh's (LGPG 2.1) hash function
+ * From: http://www.azillionmonkeys.com/qed/hash.html
+ */
+
+#define get16bits(d) (*((const __u16 *) (d)))
+
+static __always_inline
+__u32 SuperFastHash (const char *data, int len, __u32 initval) {
+ __u32 hash = initval;
+ __u32 tmp;
+ int rem;
+
+ if (len <= 0 || data == NULL) return 0;
+
+ rem = len & 3;
+ len >>= 2;
+
+ /* Main loop */
+#pragma clang loop unroll(full)
+ for (;len > 0; len--) {
+ hash += get16bits (data);
+ tmp = (get16bits (data+2) << 11) ^ hash;
+ hash = (hash << 16) ^ tmp;
+ data += 2*sizeof (__u16);
+ hash += hash >> 11;
+ }
+
+ /* Handle end cases */
+ switch (rem) {
+ case 3: hash += get16bits (data);
+ hash ^= hash << 16;
+ hash ^= ((signed char)data[sizeof (__u16)]) << 18;
+ hash += hash >> 11;
+ break;
+ case 2: hash += get16bits (data);
+ hash ^= hash << 11;
+ hash += hash >> 17;
+ break;
+ case 1: hash += (signed char)*data;
+ hash ^= hash << 10;
+ hash += hash >> 1;
+ }
+
+ /* Force "avalanching" of final 127 bits */
+ hash ^= hash << 3;
+ hash += hash >> 5;
+ hash ^= hash << 4;
+ hash += hash >> 17;
+ hash ^= hash << 25;
+ hash += hash >> 6;
+
+ return hash;
+}