RFR [XS] : 8219112: name_and_sig_as_C_string usages in frame_s390 miss ResourceMark

[Doerr, Martin]

Hi Matthias,

we would get "fatal error: memory leak: allocating without ResourceMark" in the debug build if there was no ResourceMark at all on the stack. However, the existing one may be at a bad position where its scope never gets left and the resources never get freed. This situation can't get detected automatically.

In the example below (nativeInst_ppc.cpp), I think we should add one. At least, I couldn't find one at a good place.

Yes, the current process is error prone. ResourceMarks can also easily get placed at wrong positions leading to "assert... re-allocated with a different ResourceMark".

Best regards,
Martin


-----Original Message-----
From: hotspot-dev <hotspot-dev-bounces at openjdk.java.net> On Behalf Of Baesken, Matthias
Sent: Montag, 18. Februar 2019 14:40
To: Aleksey Shipilev <shade at redhat.com>; 'hotspot-dev at openjdk.java.net' <hotspot-dev at openjdk.java.net>
Subject: RE: RFR [XS] : 8219112: name_and_sig_as_C_string usages in frame_s390 miss ResourceMark

Hi Aleksey and Lutz , thanks  for  the reviews.


One (maybe stupid)  general   question  -  is there an easy way to find out  all locations  of missing ResourceMark usages ?
Currently  it looks to me  like a very  error prone process .

The name_and_sig_as_C_string()  issue  in this  CR   seems to be an easy and simple case .


But in  other cases  it is  (for me at least)   not so easy to say - is the ResourceMark missing  or  is it  somewhere located  in the calling functions ?
One example :

src/hotspot/cpu/ppc/nativeInst_ppc.cpp

363  void NativeGeneralJump::insert_unconditional(address code_pos, address entry) {
364    CodeBuffer cb(code_pos, BytesPerInstWord + 1);
365    MacroAssembler* a = new MacroAssembler(&cb);
366    a->b(entry);
367    ICache::ppc64_flush_icache_bytes(code_pos, NativeGeneralJump::instruction_size);
368  }

 Do we need the ResouceMark here or not ?

Best regards, Matthias



> -----Original Message-----
> From: Aleksey Shipilev <shade at redhat.com>
> Sent: Montag, 18. Februar 2019 12:55
> To: Baesken, Matthias <matthias.baesken at sap.com>; 'hotspot-
> dev at openjdk.java.net' <hotspot-dev at openjdk.java.net>
> Subject: Re: RFR [XS] : 8219112: name_and_sig_as_C_string usages in
> frame_s390 miss ResourceMark
> 
> On 2/18/19 9:47 AM, Baesken, Matthias wrote:
> > Bug/webrev :
> > http://cr.openjdk.java.net/~mbaesken/webrevs/8219112.0/
> 
> Looks good and trivial.
> 
> -Aleksey