RFR 8242263: Diagnose synchronization on primitive wrappers

[Patricio Chilano]

Hi Martin,

On 8/7/20 12:58 AM, Doerr, Martin wrote:
> Hi Patricio,
>
> thanks for the update.
>
> Sorry for causing trouble related to the tbnz instructions on aarch64.
> My concern was basically to use the correct number of Bytes for the load instructions.
> You have fixed that in webrev v3. Thanks.
>
> Unfortunately, I did the same mistake regarding the flag requirements on PPC64 and s390. And we have a wrong label on PPC64 (otherwise branch destination can be too far).
> Test duration is still terrible with the slow debug build. I still got timeouts. (Maybe I should better use fast debug builds.)
I measured the time in my Mac (fastdebug build). The FatalTest takes ~ 
less than a second to run, and we have 7*8=56 of those. The LogTest 
takes between 1-4 seconds depending on the flag, and we have 7 of those. 
Overall it takes 2-3 minutes to run. Maybe you can measure those times 
too to see where its taking so long?

> Fixes see below.
Great, added the new fixes. Here is v4:

Full: http://cr.openjdk.java.net/~pchilanomate/8242263/v4/webrev/
Inc: http://cr.openjdk.java.net/~pchilanomate/8242263/v4/inc/webrev/ 
<http://cr.openjdk.java.net/~pchilanomate/8242263/v4/webrev/>

> Sometimes simple changes can require quite some time ...
Yep, no problem  : )

Thanks!


Patricio
> Best regards,
> Martin
>
>
> diff -r f629202b3862 src/hotspot/cpu/ppc/c1_MacroAssembler_ppc.cpp
> --- a/src/hotspot/cpu/ppc/c1_MacroAssembler_ppc.cpp     Thu Aug 06 22:03:39 2020 +0200
> +++ b/src/hotspot/cpu/ppc/c1_MacroAssembler_ppc.cpp     Thu Aug 06 23:26:02 2020 +0200
> @@ -109,7 +109,7 @@
>       load_klass(Rscratch, Roop);
>       lwz(Rscratch, in_bytes(Klass::access_flags_offset()), Rscratch);
>       testbitdi(CCR0, R0, Rscratch, exact_log2(JVM_ACC_IS_BOX_CLASS));
> -    bne(CCR0, slow_case);
> +    bne(CCR0, slow_int);
>     }
>
>     if (UseBiasedLocking) {
> diff -r f629202b3862 src/hotspot/cpu/ppc/macroAssembler_ppc.cpp
> --- a/src/hotspot/cpu/ppc/macroAssembler_ppc.cpp        Thu Aug 06 22:03:39 2020 +0200
> +++ b/src/hotspot/cpu/ppc/macroAssembler_ppc.cpp        Thu Aug 06 23:26:02 2020 +0200
> @@ -2839,8 +2839,8 @@
>     if (DiagnoseSyncOnPrimitiveWrappers != 0) {
>       load_klass(temp, oop);
>       lwz(temp, in_bytes(Klass::access_flags_offset()), temp);
> -    testbitdi(CCR0, R0, temp, exact_log2(JVM_ACC_IS_BOX_CLASS));
> -    bne(CCR0, cont);
> +    testbitdi(flag, R0, temp, exact_log2(JVM_ACC_IS_BOX_CLASS));
> +    bne(flag, cont);
>     }
>
>     if (try_bias) {
> diff -r f629202b3862 src/hotspot/cpu/s390/macroAssembler_s390.cpp
> --- a/src/hotspot/cpu/s390/macroAssembler_s390.cpp      Thu Aug 06 22:03:39 2020 +0200
> +++ b/src/hotspot/cpu/s390/macroAssembler_s390.cpp      Thu Aug 06 23:26:02 2020 +0200
> @@ -3360,8 +3360,10 @@
>
>     if (DiagnoseSyncOnPrimitiveWrappers != 0) {
>       load_klass(Z_R1_scratch, oop);
> -    testbit(Address(Z_R1_scratch, Klass::access_flags_offset()), exact_log2(JVM_ACC_IS_BOX_CLASS));
> -    z_btrue(done);
> +    z_l(Z_R1_scratch, Address(Z_R1_scratch, Klass::access_flags_offset()));
> +    assert((JVM_ACC_IS_BOX_CLASS & 0xFFFF) == 0, "or change following instruction");
> +    z_nilh(Z_R1_scratch, JVM_ACC_IS_BOX_CLASS >> 16);
> +    z_brne(done);
>     }
>
>     if (try_bias) {
> diff -r f629202b3862 test/hotspot/jtreg/runtime/Monitor/SyncOnPrimitiveWrapperTest.java
> --- a/test/hotspot/jtreg/runtime/Monitor/SyncOnPrimitiveWrapperTest.java        Thu Aug 06 22:03:39 2020 +0200
> +++ b/test/hotspot/jtreg/runtime/Monitor/SyncOnPrimitiveWrapperTest.java        Thu Aug 06 23:26:02 2020 +0200
> @@ -31,7 +31,7 @@
>    * @bug 8242263
>    * @summary Exercise DiagnoseSyncOnPrimitiveWrappers diagnostic flag
>    * @library /test/lib
> - * @run driver SyncOnPrimitiveWrapperTest
> + * @run driver/timeout=180000 SyncOnPrimitiveWrapperTest
>    */
>
>   public class SyncOnPrimitiveWrapperTest {
>