From 128c22b9980fd032629f46fa15ec6a2024ced399 Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Fri, 23 Jul 2021 08:45:46 -0700 Subject: [PATCH] eal: fix argument in 32-bit safe BSF function The first argument to rte_bsf32_safe was incorrectly declared as a 64 bit value. The code only works on 32 bit values and the underlying function rte_bsf32 only accepts 32 bit values. This was a mistake introduced when the safe version was added and probably cause by copy/paste from the 64 bit version. The bug passed silently under the radar until some other code was built with -Wall and -Wextra in C++ and C++ complains about the missing cast. Yes, this is a API signature change, but the original code was wrong. It is an inline so not an ABI change. Fixes: 4e261f551986 ("eal: add 64-bit bsf and 32-bit safe bsf functions") Cc: stable@dpdk.org Signed-off-by: Stephen Hemminger Acked-by: Tyler Retzlaff --- doc/guides/rel_notes/release_21_08.rst | 4 ++++ lib/eal/include/rte_common.h | 2 +- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/doc/guides/rel_notes/release_21_08.rst b/doc/guides/rel_notes/release_21_08.rst index 9904a0e390..de76d69c4e 100644 --- a/doc/guides/rel_notes/release_21_08.rst +++ b/doc/guides/rel_notes/release_21_08.rst @@ -202,6 +202,10 @@ API Changes * eal: ``rte_strscpy`` sets ``rte_errno`` to ``E2BIG`` in case of string truncation. +* eal: ``rte_bsf32_safe`` now takes a 32-bit value for its first argument. + This fixes warnings about loss of precision + when used with some compilers settings. + * eal: ``rte_power_monitor`` and the ``rte_power_monitor_cond`` struct changed to use a callback mechanism. diff --git a/lib/eal/include/rte_common.h b/lib/eal/include/rte_common.h index d5a32c66a5..99eb5f1820 100644 --- a/lib/eal/include/rte_common.h +++ b/lib/eal/include/rte_common.h @@ -623,7 +623,7 @@ rte_bsf32(uint32_t v) * Returns 0 if ``v`` was 0, otherwise returns 1. */ static inline int -rte_bsf32_safe(uint64_t v, uint32_t *pos) +rte_bsf32_safe(uint32_t v, uint32_t *pos) { if (v == 0) return 0; -- 2.20.1