A number of drivers define the DIV_ROUND_UP macro -- add it to rte_common.h so that other code looking to use that functionality doesn't have to re-define it.
Signed-off-by: Joshua Washington <[email protected]> --- Changes in v3: - Add unit tests in app/test/test_common.c. - Add release notes entry. - Enhance Doxygen documentation to document parameters and caveats (divisor evaluation, non-negative inputs, wraparound). Changes in v2: - Split out patches replacing usages --- app/test/test_common.c | 10 ++++++++++ doc/guides/rel_notes/release_26_11.rst | 5 +++++ lib/eal/include/rte_common.h | 18 ++++++++++++++++++ 3 files changed, 33 insertions(+) diff --git a/app/test/test_common.c b/app/test/test_common.c index 3e1c7df0c1..bce2776ea6 100644 --- a/app/test/test_common.c +++ b/app/test/test_common.c @@ -47,6 +47,16 @@ test_macros(int __rte_unused unused_parm) "RTE_MAX"); RTE_TEST_ASSERT_EQUAL(RTE_MIN(SMALLER, BIGGER), SMALLER, "RTE_MIN"); + RTE_TEST_ASSERT_EQUAL(RTE_DIV_ROUND_UP(10, 5), 2, + "RTE_DIV_ROUND_UP exact"); + RTE_TEST_ASSERT_EQUAL(RTE_DIV_ROUND_UP(11, 5), 3, + "RTE_DIV_ROUND_UP remainder"); + RTE_TEST_ASSERT_EQUAL(RTE_DIV_ROUND_UP(0, 5), 0, + "RTE_DIV_ROUND_UP n=0"); + RTE_TEST_ASSERT_EQUAL(RTE_DIV_ROUND_UP(0, 1), 0, + "RTE_DIV_ROUND_UP n=0, d=1"); + RTE_TEST_ASSERT_EQUAL(RTE_DIV_ROUND_UP(5, 1), 5, + "RTE_DIV_ROUND_UP d=1"); RTE_TEST_ASSERT_EQUAL(RTE_PTR_ADD(arr + 1, sizeof(arr[0])), &arr[2], "RTE_PTR_ADD(expr, x)"); diff --git a/doc/guides/rel_notes/release_26_11.rst b/doc/guides/rel_notes/release_26_11.rst index c8cc86295d..7720fd9f96 100644 --- a/doc/guides/rel_notes/release_26_11.rst +++ b/doc/guides/rel_notes/release_26_11.rst @@ -55,6 +55,11 @@ New Features Also, make sure to start the actual text at the margin. ======================================================= +* **Added division round up macro.** + + Added the ``RTE_DIV_ROUND_UP`` macro in ``rte_common.h`` to divide dividend + by divisor, rounding up to the nearest integer. + Removed Items ------------- diff --git a/lib/eal/include/rte_common.h b/lib/eal/include/rte_common.h index 79d2a0ab93..9707f7e255 100644 --- a/lib/eal/include/rte_common.h +++ b/lib/eal/include/rte_common.h @@ -717,6 +717,24 @@ static void __attribute__((destructor(RTE_PRIO(prio)), used)) func(void) (ceil - (v)) > ((v) - floor) ? floor : ceil; \ }) +/** + * Macro to divide dividend @p n by divisor @p d, rounding up if @p d does not divide @p n. + * + * @param n + * Dividend. Must be a non-negative integer to round correctly. + * @param d + * Divisor. Must be a positive integer. Evaluated twice. + * @return + * Result of dividing @p n by @p d, rounded up. + * + * @note The divisor @p d is evaluated twice. Arguments must not have side effects. + * @note Both @p n and @p d must be non-negative to round correctly. + * @note The sum @c (n) + (d) - 1 can wrap around if @p n is close to the maximum + * representable value of its type (e.g. RTE_DIV_ROUND_UP(UINT32_MAX, 2) + * on uint32_t wraps to 0). + */ +#define RTE_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d)) + /** * Checks if a pointer is aligned to a given power-of-two value * -- 2.55.0.1082.g2b9226bbc0-goog
