ERROR: PgLwLock is not initialized

[ccleve]

The code in pgrx-examples/shmem has an issue. Possibly pg_shmem_init!() is missing something?

To duplicate the problem:

clone pgrx
cd pgrx-examples/shmem
cargo pgrx run

then:

shmem=# create extension shmem;
CREATE EXTENSION
shmem=# select hash_insert(42,42);
ERROR:  PgLwLock is not initialized
DETAIL:  
   0: std::backtrace_rs::backtrace::libunwind::trace
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/../../backtrace/src/backtrace/libunwind.rs:116:5
   1: std::backtrace_rs::backtrace::trace_unsynchronized
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2: std::backtrace::Backtrace::create
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/backtrace.rs:331:13
   3: pgrx_pg_sys::submodules::panic::register_pg_guard_panic_hook::{{closure}}::{{closure}}
             at /Users/ccleve/dev/pg/pgrx/pgrx-pg-sys/src/submodules/panic.rs:316:43
   4: std::thread::local::LocalKey<T>::try_with
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/thread/local.rs:283:12
   5: std::thread::local::LocalKey<T>::with
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/thread/local.rs:260:9
   6: pgrx_pg_sys::submodules::panic::register_pg_guard_panic_hook::{{closure}}
             at /Users/ccleve/dev/pg/pgrx/pgrx-pg-sys/src/submodules/panic.rs:313:13
   7: <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/alloc/src/boxed.rs:2077:9
   8: std::panicking::rust_panic_with_hook
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/panicking.rs:799:13
   9: std::panicking::begin_panic_handler::{{closure}}
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/panicking.rs:656:13
  10: std::sys_common::backtrace::__rust_end_short_backtrace
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/sys_common/backtrace.rs:171:18
  11: rust_begin_unwind
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/panicking.rs:652:5
  12: core::panicking::panic_fmt
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/core/src/panicking.rs:72:14
  13: pgrx::lwlock::PgLwLockInner<T>::exclusive
             at /Users/ccleve/dev/pg/pgrx/pgrx/src/lwlock.rs:126:13
  14: pgrx::lwlock::PgLwLock<T>::exclusive
             at /Users/ccleve/dev/pg/pgrx/pgrx/src/lwlock.rs:77:18
  15: shmem::hash_insert
             at /Users/ccleve/dev/pg/pgrx/pgrx-examples/shmem/src/lib.rs:123:5
  16: shmem::hash_insert_wrapper::_internal_wrapper::{{closure}}
             at /Users/ccleve/dev/pg/pgrx/pgrx-examples/shmem/src/lib.rs:122:38
  17: pgrx::memcxt::PgMemoryContexts::exec_in_context
             at /Users/ccleve/dev/pg/pgrx/pgrx/src/memcxt.rs:590:22
  18: pgrx::memcxt::PgMemoryContexts::switch_to
             at /Users/ccleve/dev/pg/pgrx/pgrx/src/memcxt.rs:402:18
  19: shmem::hash_insert_wrapper::_internal_wrapper
             at /Users/ccleve/dev/pg/pgrx/pgrx-examples/shmem/src/lib.rs:122:38
  20: shmem::hash_insert_wrapper::{{closure}}
             at /Users/ccleve/dev/pg/pgrx/pgrx-examples/shmem/src/lib.rs:122:38
  21: <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/core/src/panic/unwind_safe.rs:272:9
  22: std::panicking::try::do_call
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/panicking.rs:559:40
  23: ___rust_try
  24: std::panicking::try
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/panicking.rs:523:19
  25: std::panic::catch_unwind
             at /rustc/3f5fd8dd41153bc5fdca9427e9e05be2c767ba23/library/std/src/panic.rs:149:14
  26: pgrx_pg_sys::submodules::panic::run_guarded
             at /Users/ccleve/dev/pg/pgrx/pgrx-pg-sys/src/submodules/panic.rs:419:11
  27: pgrx_pg_sys::submodules::panic::pgrx_extern_c_guard
             at /Users/ccleve/dev/pg/pgrx/pgrx-pg-sys/src/submodules/panic.rs:395:20
  28: hash_insert_wrapper
             at /Users/ccleve/dev/pg/pgrx/pgrx-examples/shmem/src/lib.rs:122:38
  29: ExecInterpExpr
             at /Users/ccleve/.pgrx/13.16/src/backend/executor/execExprInterp.c:704:8
  30: ExecEvalExprSwitchContext
             at /Users/ccleve/.pgrx/13.16/src/backend/executor/../../../src/include/executor/executor.h:322:13
  31: ExecProject
             at /Users/ccleve/.pgrx/13.16/src/backend/executor/../../../src/include/executor/executor.h:356:9
  32: ExecResult
             at /Users/ccleve/.pgrx/13.16/src/backend/executor/nodeResult.c:136:10
  33: ExecProcNode
             at /Users/ccleve/.pgrx/13.16/src/backend/executor/../../../src/include/executor/executor.h:248:9
  34: ExecutePlan
             at /Users/ccleve/.pgrx/13.16/src/backend/executor/execMain.c:1632:10
  35: standard_ExecutorRun
             at /Users/ccleve/.pgrx/13.16/src/backend/executor/execMain.c:350:3
  36: PortalRunSelect
             at /Users/ccleve/.pgrx/13.16/src/backend/tcop/pquery.c:921:4
  37: PortalRun
             at /Users/ccleve/.pgrx/13.16/src/backend/tcop/pquery.c:765:18
  38: exec_simple_query
             at /Users/ccleve/.pgrx/13.16/src/backend/tcop/postgres.c:1241:10
  39: PostgresMain
  40: BackendRun
             at /Users/ccleve/.pgrx/13.16/src/backend/postmaster/postmaster.c:4560:2
  41: BackendStartup
             at /Users/ccleve/.pgrx/13.16/src/backend/postmaster/postmaster.c:4244:3
  42: ServerLoop
             at /Users/ccleve/.pgrx/13.16/src/backend/postmaster/postmaster.c:1742:7
  43: PostmasterMain
             at /Users/ccleve/.pgrx/13.16/src/backend/postmaster/postmaster.c:1415:11
  44: main
             at /Users/ccleve/.pgrx/13.16/src/backend/main/main.c:210:3

[workingjubilee]

how far back does this go?

[workingjubilee]

pgrx 0.11.4:

shmem=# CREATE EXTENSION shmem;
ERROR:  extension "shmem" already exists
shmem=# select hash_insert(42,42);
ERROR:  Can't give out exclusive, lock is in an empty state
shmem=# 

[workingjubilee]

cc @JelteF @eeeebbbbrrrr can you take a look at this? thanks.