From b9c8c57e983246ec034bc9059b1740558c951d51 Mon Sep 17 00:00:00 2001 From: Dave Barach Date: Thu, 16 Mar 2023 13:03:47 -0400 Subject: vppinfra: fix corner-cases in bihash lookup In a case where one pounds on a single kvp in a KVP_AT_BUCKET_LEVEL table, the code would sporadically return a transitional value (junk) from a half-deleted kvp. At most, 64-bits worth of the kvp will be written atomically, so using memset(...) to smear 0xFF's across a kvp to free it left a lot to be desired. Performance impact: very mild positive, thanks to FC for doing a multi-thread host stack perf/scale test. Added an ASSERT to catch attempts to add a (key,value) pair which contains the magic "free kvp" value. Type: fix Signed-off-by: Dave Barach Change-Id: I6a1aa8a2c30bc70bec4b696ce7b17c2839927065 --- src/vppinfra/test_bihash_template.c | 65 +++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) (limited to 'src/vppinfra/test_bihash_template.c') diff --git a/src/vppinfra/test_bihash_template.c b/src/vppinfra/test_bihash_template.c index 155b8bd408d..af3ebb2ef0e 100644 --- a/src/vppinfra/test_bihash_template.c +++ b/src/vppinfra/test_bihash_template.c @@ -247,6 +247,59 @@ test_bihash_threads (test_main_t * tm) return 0; } +static clib_error_t * +test_bihash_vanilla_overwrite (test_main_t *tm) +{ + int i; + BVT (clib_bihash) * h; + BVT (clib_bihash_kv) kv; + + h = &tm->hash; + +#if BIHASH_32_64_SVM + BV (clib_bihash_initiator_init_svm) + (h, "test", tm->nbuckets, 0x30000000 /* base_addr */, tm->hash_memory_size); +#else + BV (clib_bihash_init) (h, "test", tm->nbuckets, tm->hash_memory_size); +#endif + + for (i = 0; i < 100; i++) + { + kv.key = 12345; + kv.value = i; + + BV (clib_bihash_add_del) (h, &kv, 1 /* is_add */); + } + + fformat (stdout, "End of run, should one item...\n"); + fformat (stdout, "%U", BV (format_bihash), h, 0 /* very verbose */); + BV (clib_bihash_free) (h); + return 0; +} + +static clib_error_t * +test_bihash_value_assert (test_main_t *tm) +{ + BVT (clib_bihash) * h; + BVT (clib_bihash_kv) kv; + + h = &tm->hash; + +#if BIHASH_32_64_SVM + BV (clib_bihash_initiator_init_svm) + (h, "test", tm->nbuckets, 0x30000000 /* base_addr */, tm->hash_memory_size); +#else + BV (clib_bihash_init) (h, "test", tm->nbuckets, tm->hash_memory_size); +#endif + + kv.key = 12345; + kv.value = 0xFEEDFACE8BADF00DULL; + + fformat (stderr, "The following add should ASSERT...\n"); + BV (clib_bihash_add_del) (h, &kv, 1 /* is_add */); + + return 0; +} static clib_error_t * test_bihash (test_main_t * tm) @@ -514,6 +567,10 @@ test_bihash_main (test_main_t * tm) tm->verbose = 1; else if (unformat (i, "stale-overwrite")) which = 3; + else if (unformat (i, "overwrite")) + which = 4; + else if (unformat (i, "value-assert")) + which = 5; else return clib_error_return (0, "unknown input '%U'", format_unformat_error, i); @@ -542,6 +599,14 @@ test_bihash_main (test_main_t * tm) error = test_bihash_stale_overwrite (tm); break; + case 4: + error = test_bihash_vanilla_overwrite (tm); + break; + + case 5: + error = test_bihash_value_assert (tm); + break; + default: return clib_error_return (0, "no such test?"); } -- cgit 1.2.3-korg