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LGTM,</div>
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I'm not AVX-512 expert, but I think AVX-512 might expect 64-bytes alignment,.</div>
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As the original ALIGNMENT_UNIT is 32, so I think the selection of offsets is no problem. </div>
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Maybe remove AVX-512 from the comments ? </div>
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Regards</div>
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Kai </div>
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<b>From:</b> Stephen Hemminger <stephen@networkplumber.org><br>
<b>Sent:</b> Thursday, February 26, 2026 16:48<br>
<b>To:</b> dev@dpdk.org <dev@dpdk.org><br>
<b>Cc:</b> Stephen Hemminger <stephen@networkplumber.org>; Luca Boccassi <bluca@debian.org><br>
<b>Subject:</b> [PATCH] test/memcpy: reduce alignment offset coverage to fix timeout
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<div style="font-size: 11pt;">The memcpy test sweeps all 32x32 src/dst alignment offset pairs which<br>
causes it to timeout on slow emulated 32-bit build environments [1].<br>
<br>
Replace with a curated set of 7 offsets {0, 1, 7, 15, 16, 17, 31}<br>
that cover the interesting alignment boundaries. This reduces the<br>
iterations from 38912 to 1862 while covering the same code paths.<br>
<br>
[1] <a data-auth="NotApplicable" class="OWAAutoLink" id="OWAda924304-6866-50fb-d3fd-14b10fce3146" href="https://build.opensuse.org/package/live_build_log/home:bluca:dpdk/dpdk/Debian_Testing/i586">
https://build.opensuse.org/package/live_build_log/home:bluca:dpdk/dpdk/Debian_Testing/i586</a><br>
<br>
Reported-by: Luca Boccassi <bluca@debian.org><br>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org><br>
---<br>
app/test/test_memcpy.c | 20 ++++++++++++++++----<br>
1 file changed, 16 insertions(+), 4 deletions(-)<br>
<br>
diff --git a/app/test/test_memcpy.c b/app/test/test_memcpy.c<br>
index 7273c17a06..12e491034f 100644<br>
--- a/app/test/test_memcpy.c<br>
+++ b/app/test/test_memcpy.c<br>
@@ -36,6 +36,16 @@ static size_t buf_sizes[TEST_VALUE_RANGE];<br>
/* Data is aligned on this many bytes (power of 2) */<br>
#define ALIGNMENT_UNIT 32<br>
<br>
+/*<br>
+ * Subset of offsets to test. These values cover the structurally<br>
+ * interesting alignment cases for SSE/AVX/AVX512 copy paths:<br>
+ * aligned (0), off-by-one (1), partial vector (7, 15, 17),<br>
+ * vector boundaries (16, 31). Testing all 1024 src x dst<br>
+ * combinations of offsets 0..31 is unnecessary since many<br>
+ * map to the same code paths, and causes the test to timeout<br>
+ * on slow (e.g. emulated 32-bit) build environments.<br>
+ */<br>
+static const unsigned int test_offsets[] = {0, 1, 7, 15, 16, 17, 31};<br>
<br>
/*<br>
* Create two buffers, and initialise one with random values. These are copied<br>
@@ -103,13 +113,15 @@ static int<br>
func_test(void)<br>
{<br>
unsigned int off_src, off_dst, i;<br>
+ unsigned int n_offsets = RTE_DIM(test_offsets);<br>
int ret;<br>
<br>
- for (off_src = 0; off_src < ALIGNMENT_UNIT; off_src++) {<br>
- for (off_dst = 0; off_dst < ALIGNMENT_UNIT; off_dst++) {<br>
+ for (off_src = 0; off_src < n_offsets; off_src++) {<br>
+ for (off_dst = 0; off_dst < n_offsets; off_dst++) {<br>
for (i = 0; i < RTE_DIM(buf_sizes); i++) {<br>
- ret = test_single_memcpy(off_src, off_dst,<br>
- buf_sizes[i]);<br>
+ ret = test_single_memcpy(test_offsets[off_src],<br>
+ test_offsets[off_dst],<br>
+ buf_sizes[i]);<br>
if (ret != 0)<br>
return -1;<br>
}<br>
--<br>
2.51.0<br>
<br>
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