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authorLuca Boccassi <luca.boccassi@gmail.com>2018-11-14 11:13:11 +0000
committerLuca Boccassi <luca.boccassi@gmail.com>2018-11-14 11:13:28 +0000
commit8a853e3f0275efc8b05cb195085d45946942744a (patch)
treef7b349012231726c54fedd6c19f9cbf8234a4458 /lib/librte_eal/common/include/rte_common.h
parent88fab00d4402af240c1b7cc2566133aece115488 (diff)
New upstream version 18.11-rc3upstream/18.11-rc3
Change-Id: I958b9d019027ef049bd992b3968a667f3ae382ae Signed-off-by: Luca Boccassi <luca.boccassi@gmail.com>
Diffstat (limited to 'lib/librte_eal/common/include/rte_common.h')
-rw-r--r--lib/librte_eal/common/include/rte_common.h19
1 files changed, 19 insertions, 0 deletions
diff --git a/lib/librte_eal/common/include/rte_common.h b/lib/librte_eal/common/include/rte_common.h
index cba7bbc1..87f0f630 100644
--- a/lib/librte_eal/common/include/rte_common.h
+++ b/lib/librte_eal/common/include/rte_common.h
@@ -473,6 +473,25 @@ rte_log2_u32(uint32_t v)
return rte_bsf32(v);
}
+
+/**
+ * Return the last (most-significant) bit set.
+ *
+ * @note The last (most significant) bit is at position 32.
+ * @note rte_fls_u32(0) = 0, rte_fls_u32(1) = 1, rte_fls_u32(0x80000000) = 32
+ *
+ * @param x
+ * The input parameter.
+ * @return
+ * The last (most-significant) bit set, or 0 if the input is 0.
+ */
+static inline int
+rte_fls_u32(uint32_t x)
+{
+ return (x == 0) ? 0 : 32 - __builtin_clz(x);
+}
+
+
#ifndef offsetof
/** Return the offset of a field in a structure. */
#define offsetof(TYPE, MEMBER) __builtin_offsetof (TYPE, MEMBER)