Re: [PATCH 2/6] KVM: selftests: Avoid flooding debug log while populating memory
On Tue, Jan 12, 2021, Ben Gardon wrote: > Peter Xu pointed out that a log message printed while waiting for the > memory population phase of the dirty_log_perf_test will flood the debug > logs as there is no delay after printing the message. Since the message > does not provide much value anyway, remove it. Does it provide value if something goes wrong? E.g. if a vCPU doesn't finish, how would one go about debugging? Would it make sense to make the print ratelimited instead of removing it altogether? > Reviewed-by: Jacob Xu > > Signed-off-by: Ben Gardon > --- > tools/testing/selftests/kvm/dirty_log_perf_test.c | 9 - > 1 file changed, 4 insertions(+), 5 deletions(-) > > diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c > b/tools/testing/selftests/kvm/dirty_log_perf_test.c > index 16efe6589b43..15a9c45bdb5f 100644 > --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c > +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c > @@ -146,8 +146,7 @@ static void run_test(enum vm_guest_mode mode, void *arg) > /* Allow the vCPU to populate memory */ > pr_debug("Starting iteration %lu - Populating\n", iteration); > while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) != iteration) > - pr_debug("Waiting for vcpu_last_completed_iteration == %lu\n", > - iteration); > + ; > > ts_diff = timespec_elapsed(start); > pr_info("Populate memory time: %ld.%.9lds\n", > @@ -171,9 +170,9 @@ static void run_test(enum vm_guest_mode mode, void *arg) > > pr_debug("Starting iteration %lu\n", iteration); > for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) { > - while > (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) != iteration) > - pr_debug("Waiting for vCPU %d > vcpu_last_completed_iteration == %lu\n", > - vcpu_id, iteration); > + while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) > +!= iteration) I like the original better. Poking out past 80 chars isn't the end of the world. > + ; > } > > ts_diff = timespec_elapsed(start); > -- > 2.30.0.284.gd98b1dd5eaa7-goog >
Re: [PATCH 2/6] KVM: selftests: Avoid flooding debug log while populating memory
On 12/01/2021 22.42, Ben Gardon wrote: Peter Xu pointed out that a log message printed while waiting for the memory population phase of the dirty_log_perf_test will flood the debug logs as there is no delay after printing the message. Since the message does not provide much value anyway, remove it. Reviewed-by: Jacob Xu Signed-off-by: Ben Gardon --- tools/testing/selftests/kvm/dirty_log_perf_test.c | 9 - 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c index 16efe6589b43..15a9c45bdb5f 100644 --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c @@ -146,8 +146,7 @@ static void run_test(enum vm_guest_mode mode, void *arg) /* Allow the vCPU to populate memory */ pr_debug("Starting iteration %lu - Populating\n", iteration); while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) != iteration) - pr_debug("Waiting for vcpu_last_completed_iteration == %lu\n", - iteration); + ; ts_diff = timespec_elapsed(start); pr_info("Populate memory time: %ld.%.9lds\n", @@ -171,9 +170,9 @@ static void run_test(enum vm_guest_mode mode, void *arg) pr_debug("Starting iteration %lu\n", iteration); for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) { - while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) != iteration) - pr_debug("Waiting for vCPU %d vcpu_last_completed_iteration == %lu\n", -vcpu_id, iteration); + while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) + != iteration) + ; } ts_diff = timespec_elapsed(start); Reviewed-by: Thomas Huth
[PATCH 2/6] KVM: selftests: Avoid flooding debug log while populating memory
Peter Xu pointed out that a log message printed while waiting for the memory population phase of the dirty_log_perf_test will flood the debug logs as there is no delay after printing the message. Since the message does not provide much value anyway, remove it. Reviewed-by: Jacob Xu Signed-off-by: Ben Gardon --- tools/testing/selftests/kvm/dirty_log_perf_test.c | 9 - 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c index 16efe6589b43..15a9c45bdb5f 100644 --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c @@ -146,8 +146,7 @@ static void run_test(enum vm_guest_mode mode, void *arg) /* Allow the vCPU to populate memory */ pr_debug("Starting iteration %lu - Populating\n", iteration); while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) != iteration) - pr_debug("Waiting for vcpu_last_completed_iteration == %lu\n", - iteration); + ; ts_diff = timespec_elapsed(start); pr_info("Populate memory time: %ld.%.9lds\n", @@ -171,9 +170,9 @@ static void run_test(enum vm_guest_mode mode, void *arg) pr_debug("Starting iteration %lu\n", iteration); for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) { - while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) != iteration) - pr_debug("Waiting for vCPU %d vcpu_last_completed_iteration == %lu\n", -vcpu_id, iteration); + while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) + != iteration) + ; } ts_diff = timespec_elapsed(start); -- 2.30.0.284.gd98b1dd5eaa7-goog