[Tarantool-patches] [PATCH luajit] core: fix cdata decrementing

[Igor Munkin]

Sergey,

On 16.02.21, Sergey Kaplun wrote:
> When cdata has custom finalizer (and so LJ_GC_CDATA_FIN flag) it is not
> collected immediately, when lj_cdata_free() is called. Instead, it is
> resurrected and marked finalized, so it is collected at the next GC
> cycle. The reason of the bug is that gc_cdatanum is decremented when
> cdata is resurrected too (i.e. twice).
> 
> This patch excludes cdata decrementing from resurrection branch and
> adds corresponding tests.
> 
> Resolves tarantool/tarantool#5820
> Follows up tarantool/tarantool#5187
> ---
> 
> Branch: https://github.com/tarantool/luajit/tree/skaplun/gh-5820-improperly-cdata-counting
> Test Branch: https://github.com/tarantool/tarantool/tree/skaplun/gh-5820-improperly-cdata-counting
> Issue: https://github.com/tarantool/tarantool/issues/5820
> 
> ChangeLog entry for bumping LuaJIT:
> ===================================================================
> ## bugfix/LuaJIT
> 
> * Fix double cdata decrementing in platform metrics when finalizer is set (gh-5820).
> ===================================================================

I've changed the ChangeLog entry a bit. Hope, you don't mind.

================================================================================

## bugfix/LuaJIT

* Fixed double `gc_cdatanum` decrementing in LuaJIT platform metrics when a
  finalizer is set for GCcdata object (gh-5820).

================================================================================

> 
>  src/lj_cdata.c                                |  3 +-
>  test/misclib-getmetrics-capi.test.lua         | 15 +++++++++-
>  test/misclib-getmetrics-capi/testgetmetrics.c | 28 +++++++++++++++++++
>  test/misclib-getmetrics-lapi.test.lua         | 15 +++++++++-
>  4 files changed, 58 insertions(+), 3 deletions(-)

I've checked the patchset into tarantool-2.6, tarantool-2.7 and
tarantool branches in tarantool/luajit and bumped a new version in 2.6,
2.7 and master.

> 

<snipped>

> -- 
> 2.28.0
> 

-- 
Best regards,
IM