[1/4] test/lpm: fix cycle calculation in rcu qsbr perf

Message ID 20201029153634.10647-1-dharmik.thakkar@arm.com (mailing list archive)
State Superseded, archived
Delegated to: David Marchand
Headers
Series [1/4] test/lpm: fix cycle calculation in rcu qsbr perf |

Checks

Context Check Description
ci/checkpatch success coding style OK

Commit Message

Dharmik Thakkar Oct. 29, 2020, 3:36 p.m. UTC
  Fix incorrect calculations for LPM adds, LPM deletes,
and average cycles in RCU QSBR perf tests

Fixes: eff30b59cc2e ("test/lpm: add RCU performance tests")
Cc: honnappa.nagarahalli@arm.com
Cc: stable@dpdk.org

Signed-off-by: Dharmik Thakkar <dharmik.thakkar@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
---
 app/test/test_lpm_perf.c | 43 ++++++++++++++--------------------------
 1 file changed, 15 insertions(+), 28 deletions(-)
  

Comments

David Marchand Nov. 2, 2020, 10:08 a.m. UTC | #1
On Thu, Oct 29, 2020 at 4:37 PM Dharmik Thakkar <dharmik.thakkar@arm.com> wrote:
>
> Fix incorrect calculations for LPM adds, LPM deletes,
> and average cycles in RCU QSBR perf tests
>
> Fixes: eff30b59cc2e ("test/lpm: add RCU performance tests")
> Cc: honnappa.nagarahalli@arm.com
> Cc: stable@dpdk.org
>
> Signed-off-by: Dharmik Thakkar <dharmik.thakkar@arm.com>
> Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>

Bruce, Vladimir, reviews for this series please?
Thanks.
  
Bruce Richardson Nov. 2, 2020, 3:11 p.m. UTC | #2
On Thu, Oct 29, 2020 at 10:36:31AM -0500, Dharmik Thakkar wrote:
> Fix incorrect calculations for LPM adds, LPM deletes,
> and average cycles in RCU QSBR perf tests
> 

To help review this patch, could you provide some more details in the
commit log as to what exactly was wrong with the calculation and how this
patch fixes things?

> Fixes: eff30b59cc2e ("test/lpm: add RCU performance tests")
> Cc: honnappa.nagarahalli@arm.com
> Cc: stable@dpdk.org
> 
> Signed-off-by: Dharmik Thakkar <dharmik.thakkar@arm.com>
> Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
  
Dharmik Thakkar Nov. 2, 2020, 4:58 p.m. UTC | #3
> On Nov 2, 2020, at 9:11 AM, Bruce Richardson <bruce.richardson@intel.com> wrote:
> 
> On Thu, Oct 29, 2020 at 10:36:31AM -0500, Dharmik Thakkar wrote:
>> Fix incorrect calculations for LPM adds, LPM deletes,
>> and average cycles in RCU QSBR perf tests
>> 
> 
> To help review this patch, could you provide some more details in the
> commit log as to what exactly was wrong with the calculation and how this
> patch fixes things?
> 

I will update the commit message in the next version. Adding it here as well:

Since, rcu qsbr tests run for ‘RCU_ITERATIONS’ and not ‘ITERATIONS’,
replace ‘ITERATIONS’ with ‘RCU_ITERATIONS’ for calculating adds, deletes, and cycles.

Also, for multi-writer perf test, each writer only writes half of NUM_LDEPTH_ROUTE_ENTRIES.
For 2 writers, total adds (or deletes) should be (RCU_ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES) instead of
(2 * RCU_ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES).

Since, for both the single and multi writer tests, total adds/deletes is equal to (RCU_ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES),
this has been replaced with a macro ’TOTAL_WRITES’ and furthermore, ‘g_writes’ has been removed since it is always a fixed value 
equal to TOTAL_WRITES.

>> Fixes: eff30b59cc2e ("test/lpm: add RCU performance tests")
>> Cc: honnappa.nagarahalli@arm.com
>> Cc: stable@dpdk.org
>> 
>> Signed-off-by: Dharmik Thakkar <dharmik.thakkar@arm.com>
>> Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
  
Vladimir Medvedkin Nov. 2, 2020, 5:21 p.m. UTC | #4
Hi Dharmik,

On 02/11/2020 16:58, Dharmik Thakkar wrote:
> 
>> On Nov 2, 2020, at 9:11 AM, Bruce Richardson <bruce.richardson@intel.com> wrote:
>>
>> On Thu, Oct 29, 2020 at 10:36:31AM -0500, Dharmik Thakkar wrote:
>>> Fix incorrect calculations for LPM adds, LPM deletes,
>>> and average cycles in RCU QSBR perf tests
>>>
>>
>> To help review this patch, could you provide some more details in the
>> commit log as to what exactly was wrong with the calculation and how this
>> patch fixes things?
>>
> 
> I will update the commit message in the next version. Adding it here as well:
> 
> Since, rcu qsbr tests run for ‘RCU_ITERATIONS’ and not ‘ITERATIONS’,
> replace ‘ITERATIONS’ with ‘RCU_ITERATIONS’ for calculating adds, deletes, and cycles.
> 
> Also, for multi-writer perf test, each writer only writes half of NUM_LDEPTH_ROUTE_ENTRIES.
> For 2 writers, total adds (or deletes) should be (RCU_ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES) instead of
> (2 * RCU_ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES).
> 
> Since, for both the single and multi writer tests, total adds/deletes is equal to (RCU_ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES),
> this has been replaced with a macro ’TOTAL_WRITES’ and furthermore, ‘g_writes’ has been removed since it is always a fixed value
> equal to TOTAL_WRITES.
> 

Thanks for the clarification. I left a few comments regarding 4-th 
patch. First 3 patches LGTM, just put more details in the commit message.

>>> Fixes: eff30b59cc2e ("test/lpm: add RCU performance tests")
>>> Cc: honnappa.nagarahalli@arm.com
>>> Cc: stable@dpdk.org
>>>
>>> Signed-off-by: Dharmik Thakkar <dharmik.thakkar@arm.com>
>>> Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
>
  
Bruce Richardson Nov. 2, 2020, 5:33 p.m. UTC | #5
On Mon, Nov 02, 2020 at 04:58:43PM +0000, Dharmik Thakkar wrote:
> 
> > On Nov 2, 2020, at 9:11 AM, Bruce Richardson <bruce.richardson@intel.com> wrote:
> > 
> > On Thu, Oct 29, 2020 at 10:36:31AM -0500, Dharmik Thakkar wrote:
> >> Fix incorrect calculations for LPM adds, LPM deletes,
> >> and average cycles in RCU QSBR perf tests
> >> 
> > 
> > To help review this patch, could you provide some more details in the
> > commit log as to what exactly was wrong with the calculation and how this
> > patch fixes things?
> > 
> 
> I will update the commit message in the next version. Adding it here as well:
> 
> Since, rcu qsbr tests run for ‘RCU_ITERATIONS’ and not ‘ITERATIONS’,
> replace ‘ITERATIONS’ with ‘RCU_ITERATIONS’ for calculating adds, deletes, and cycles.
> 
> Also, for multi-writer perf test, each writer only writes half of NUM_LDEPTH_ROUTE_ENTRIES.
> For 2 writers, total adds (or deletes) should be (RCU_ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES) instead of
> (2 * RCU_ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES).
> 
> Since, for both the single and multi writer tests, total adds/deletes is equal to (RCU_ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES),
> this has been replaced with a macro ’TOTAL_WRITES’ and furthermore, ‘g_writes’ has been removed since it is always a fixed value 
> equal to TOTAL_WRITES.
> 
Thanks for the clear explanation.
  

Patch

diff --git a/app/test/test_lpm_perf.c b/app/test/test_lpm_perf.c
index c5a238b9d1e8..0a2d76a983c3 100644
--- a/app/test/test_lpm_perf.c
+++ b/app/test/test_lpm_perf.c
@@ -23,7 +23,6 @@  static struct rte_rcu_qsbr *rv;
 static volatile uint8_t writer_done;
 static volatile uint32_t thr_id;
 static uint64_t gwrite_cycles;
-static uint64_t gwrites;
 /* LPM APIs are not thread safe, use mutex to provide thread safety */
 static pthread_mutex_t lpm_mutex = PTHREAD_MUTEX_INITIALIZER;
 
@@ -60,6 +59,8 @@  static uint32_t num_ldepth_route_entries;
 #define NUM_ROUTE_ENTRIES num_route_entries
 #define NUM_LDEPTH_ROUTE_ENTRIES num_ldepth_route_entries
 
+#define TOTAL_WRITES (RCU_ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES)
+
 enum {
 	IP_CLASS_A,
 	IP_CLASS_B,
@@ -432,7 +433,6 @@  test_lpm_rcu_qsbr_writer(void *arg)
 	uint8_t core_id = (uint8_t)((uintptr_t)arg);
 	uint32_t next_hop_add = 0xAA;
 
-	RTE_SET_USED(arg);
 	/* 2 writer threads are used */
 	if (core_id % 2 == 0) {
 		si = 0;
@@ -472,9 +472,6 @@  test_lpm_rcu_qsbr_writer(void *arg)
 	total_cycles = rte_rdtsc_precise() - begin;
 
 	__atomic_fetch_add(&gwrite_cycles, total_cycles, __ATOMIC_RELAXED);
-	__atomic_fetch_add(&gwrites,
-			2 * NUM_LDEPTH_ROUTE_ENTRIES * RCU_ITERATIONS,
-			__ATOMIC_RELAXED);
 
 	return 0;
 }
@@ -528,7 +525,6 @@  test_lpm_rcu_perf_multi_writer(void)
 
 	writer_done = 0;
 	__atomic_store_n(&gwrite_cycles, 0, __ATOMIC_RELAXED);
-	__atomic_store_n(&gwrites, 0, __ATOMIC_RELAXED);
 
 	__atomic_store_n(&thr_id, 0, __ATOMIC_SEQ_CST);
 
@@ -548,13 +544,10 @@  test_lpm_rcu_perf_multi_writer(void)
 		if (rte_eal_wait_lcore(enabled_core_ids[i]) < 0)
 			goto error;
 
-	printf("Total LPM Adds: %d\n",
-		2 * ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES);
-	printf("Total LPM Deletes: %d\n",
-		2 * ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES);
+	printf("Total LPM Adds: %d\n", TOTAL_WRITES);
+	printf("Total LPM Deletes: %d\n", TOTAL_WRITES);
 	printf("Average LPM Add/Del: %"PRIu64" cycles\n",
-		__atomic_load_n(&gwrite_cycles, __ATOMIC_RELAXED) /
-			__atomic_load_n(&gwrites, __ATOMIC_RELAXED)
+		__atomic_load_n(&gwrite_cycles, __ATOMIC_RELAXED) / TOTAL_WRITES
 		);
 
 	/* Wait and check return value from reader threads */
@@ -581,7 +574,6 @@  test_lpm_rcu_perf_multi_writer(void)
 
 	writer_done = 0;
 	__atomic_store_n(&gwrite_cycles, 0, __ATOMIC_RELAXED);
-	__atomic_store_n(&gwrites, 0, __ATOMIC_RELAXED);
 	__atomic_store_n(&thr_id, 0, __ATOMIC_SEQ_CST);
 
 	/* Launch reader threads */
@@ -600,14 +592,11 @@  test_lpm_rcu_perf_multi_writer(void)
 		if (rte_eal_wait_lcore(enabled_core_ids[i]) < 0)
 			goto error;
 
-	printf("Total LPM Adds: %d\n",
-		2 * ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES);
-	printf("Total LPM Deletes: %d\n",
-		2 * ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES);
+	printf("Total LPM Adds: %d\n", TOTAL_WRITES);
+	printf("Total LPM Deletes: %d\n", TOTAL_WRITES);
 	printf("Average LPM Add/Del: %"PRIu64" cycles\n",
-		__atomic_load_n(&gwrite_cycles, __ATOMIC_RELAXED) /
-			__atomic_load_n(&gwrites, __ATOMIC_RELAXED)
-		);
+		__atomic_load_n(&gwrite_cycles, __ATOMIC_RELAXED)
+		/ TOTAL_WRITES);
 
 	writer_done = 1;
 	/* Wait and check return value from reader threads */
@@ -711,11 +700,10 @@  test_lpm_rcu_perf(void)
 	}
 	total_cycles = rte_rdtsc_precise() - begin;
 
-	printf("Total LPM Adds: %d\n", ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES);
-	printf("Total LPM Deletes: %d\n",
-		ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES);
+	printf("Total LPM Adds: %d\n", TOTAL_WRITES);
+	printf("Total LPM Deletes: %d\n", TOTAL_WRITES);
 	printf("Average LPM Add/Del: %g cycles\n",
-		(double)total_cycles / (NUM_LDEPTH_ROUTE_ENTRIES * ITERATIONS));
+		(double)total_cycles / TOTAL_WRITES);
 
 	writer_done = 1;
 	/* Wait and check return value from reader threads */
@@ -771,11 +759,10 @@  test_lpm_rcu_perf(void)
 	}
 	total_cycles = rte_rdtsc_precise() - begin;
 
-	printf("Total LPM Adds: %d\n", ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES);
-	printf("Total LPM Deletes: %d\n",
-		ITERATIONS * NUM_LDEPTH_ROUTE_ENTRIES);
+	printf("Total LPM Adds: %d\n", TOTAL_WRITES);
+	printf("Total LPM Deletes: %d\n", TOTAL_WRITES);
 	printf("Average LPM Add/Del: %g cycles\n",
-		(double)total_cycles / (NUM_LDEPTH_ROUTE_ENTRIES * ITERATIONS));
+		(double)total_cycles / TOTAL_WRITES);
 
 	writer_done = 1;
 	/* Wait and check return value from reader threads */