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| author | Paolo Bonzini <pbonzini@redhat.com> | 2018-03-09 12:12:29 +0100 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2018-03-12 16:12:47 +0100 |
| commit | b9b758175424857a900c3253ffb8e55fa0a3fdd6 (patch) | |
| tree | bbd765277510d62f1080278c1dc4b23bb4a37f7a /tests/rcutorture.c | |
| parent | 148b2ba1145af29a7afac349b8169790e06d6df4 (diff) | |
| download | qemu-b9b758175424857a900c3253ffb8e55fa0a3fdd6.tar.gz | |
rcutorture: remove synchronize_rcu from readers
This gives much worse numbers for readers, especially if synchronize_rcu
is made more expensive as is the case with --enable-membarrier. Before:
$ tests/rcutorture 10 stress 10
n_reads: 98304 n_updates: 529 n_mberror: 0
rcu_stress_count: 98302 2 0 0 0 0 0 0 0 0 0
After:
$ tests/rcutorture 10 stress 10
n_reads: 165158482 n_updates: 429 n_mberror: 0
rcu_stress_count: 165154364 4118 0 0 0 0 0 0 0 0 0
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'tests/rcutorture.c')
| -rw-r--r-- | tests/rcutorture.c | 4 |
1 files changed, 0 insertions, 4 deletions
diff --git a/tests/rcutorture.c b/tests/rcutorture.c index 4002ecf123..49311c82ea 100644 --- a/tests/rcutorture.c +++ b/tests/rcutorture.c @@ -238,7 +238,6 @@ long long rcu_stress_count[RCU_STRESS_PIPE_LEN + 1]; static void *rcu_read_stress_test(void *arg) { int i; - int itercnt = 0; struct rcu_stress *p; int pc; long long n_reads_local = 0; @@ -269,9 +268,6 @@ static void *rcu_read_stress_test(void *arg) } rcu_stress_local[pc]++; n_reads_local++; - if ((++itercnt % 0x1000) == 0) { - synchronize_rcu(); - } } qemu_mutex_lock(&counts_mutex); n_reads += n_reads_local; |