Remove GLV unlocking at all functions which process data modifiable in a second thread#723
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Remove GLV unlocking at all functions which process data modifiable in a second thread#723larskanis wants to merge 1 commit into
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…n a second thread This removes possible VM crashs when data to be sent is modified/cleared in a second thread. It works by keeping the GVL lock for libpq functions that don't immediately process all the data and don't make a copy of it. These are the `PQsend*`, `PQexec*` and some related functions. Since pg-1.3 all the blocking functions or states are avoided by using the non-blocking API of libpq. Therefore holding the GVL somewhat longer shouldn't matter that much. Having some libpq function with and without unlocked GVL, results in `rb_thread_call_with_gvl()` sometimes needed and sometimes not to process callbacks. Therefore `ruby_thread_has_gvl_p()` is used to check if it's needed on ruby<4.0. In ruby-4.0+ `rb_thread_call_with_gvl()` doesn't care about whether GVL is already locked or not, so that it can be called in both cases. Fixes #721
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This removes possible VM crashs when data to be sent is modified/cleared in a second thread.
It works by keeping the GVL lock for libpq functions that don't immediately process all the data and don't make a copy of it.
These are the
PQsend*,PQexec*and some related functions.Since pg-1.3 all the blocking functions or states are avoided by using the non-blocking API of libpq.
Therefore holding the GVL somewhat longer shouldn't matter that much.
Having some libpq function with and without unlocked GVL, results in
rb_thread_call_with_gvl()sometimes needed and sometimes not to process callbacks.Therefore
ruby_thread_has_gvl_p()is used to check if it's needed on ruby<4.0.In ruby-4.0+
rb_thread_call_with_gvl()doesn't care about whether GVL is already locked or not, so that it can be called in both cases.Fixes #721