d/numam-dpdk
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

test/common: fix log2 check

Browse Source 
We recently started to get random failures on the common_autotest ut with
clang on Ubuntu 16.04.6.

Example: https://travis-ci.com/DPDK/dpdk/jobs/263177424

Wrong rte_log2_u64(0) val 0, expected ffffffff
Test Failed

The ut passes 0 to log2() to get an expected value.

Quoting log2 / log(3) manual:
If x is zero, then a pole error occurs, and the functions return
-HUGE_VAL, -HUGE_VALF, or -HUGE_VALL, respectively.

rte_log2_uXX helpers handle 0 as a special value and return 0.
Let's have dedicated tests for this case.

Fixes: 05c4345ef5 ("test: add unit test for integer log2 function")
Cc: stable@dpdk.org

Signed-off-by: David Marchand <david.marchand@redhat.com>
Acked-by: Aaron Conole <aconole@redhat.com>
This commit is contained in:
David Marchand 2019-12-20 15:01:49 +01:00
parent f26c2b39b2
commit 30a0df64aa
2 changed files with 19 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
app/test/test_common.c
View File

@ -216,7 +216,19 @@ test_log2(void)
const uint32_t max = 0x10000;
const uint32_t step = 1;
for (i = 0; i < max; i = i + step) {
compare = rte_log2_u32(0);
if (compare != 0) {
printf("Wrong rte_log2_u32(0) val %x, expected 0\n", compare);
return TEST_FAILED;
}
compare = rte_log2_u64(0);
if (compare != 0) {
printf("Wrong rte_log2_u64(0) val %x, expected 0\n", compare);
return TEST_FAILED;
}
for (i = 1; i < max; i = i + step) {
uint64_t i64;
/* extend range for 64-bit */

6
lib/librte_eal/common/include/rte_common.h
View File

@ -538,6 +538,9 @@ rte_bsf32_safe(uint64_t v, uint32_t *pos)
/**
* Return the rounded-up log2 of a integer.
*
* @note Contrary to the logarithm mathematical operation,
* rte_log2_u32(0) == 0 and not -inf.
*
* @param v
* The input parameter.
* @return
@ -632,6 +635,9 @@ rte_fls_u64(uint64_t x)
/**
* Return the rounded-up log2 of a 64-bit integer.
*
* @note Contrary to the logarithm mathematical operation,
* rte_log2_u64(0) == 0 and not -inf.
*
* @param v
* The input parameter.
* @return