diff options
| -rw-r--r-- | indra/llcommon/llrand.cpp | 25 |
1 files changed, 21 insertions, 4 deletions
diff --git a/indra/llcommon/llrand.cpp b/indra/llcommon/llrand.cpp index 2c51e6f07f..513613f543 100644 --- a/indra/llcommon/llrand.cpp +++ b/indra/llcommon/llrand.cpp @@ -58,9 +58,26 @@ * to restore uniform distribution. */ -// gRandomGenerator is a stateful static object, which is therefore not +// pRandomGenerator is a stateful static object, which is therefore not // inherently thread-safe. -static thread_local LLRandLagFib2281 gRandomGenerator(LLUUID::getRandomSeed()); +//We use a pointer to not construct a huge object in the TLS space, sadly this is necessary +// due to libcef.so on Linux being compiled with TLS model initial-exec (resulting in +// FLAG STATIC_TLS, see readelf libcef.so). CEFs own TLS objects + LLRandLagFib2281 then will exhaust the +// available TLS space, causing media failure. + +static thread_local std::unique_ptr< LLRandLagFib2281 > pRandomGenerator = nullptr; + +namespace { + F64 ll_internal_get_rand() + { + if( !pRandomGenerator ) + { + pRandomGenerator.reset(new LLRandLagFib2281(LLUUID::getRandomSeed( ) )); + } + + return(*pRandomGenerator)(); + } +} // no default implementation, only specific F64 and F32 specializations template <typename REAL> @@ -73,7 +90,7 @@ inline F64 ll_internal_random<F64>() // CPUs (or at least multi-threaded processes) seem to // occasionally give an obviously incorrect random number -- like // 5^15 or something. Sooooo, clamp it as described above. - F64 rv{ gRandomGenerator() }; + F64 rv{ ll_internal_get_rand() }; if(!((rv >= 0.0) && (rv < 1.0))) return fmod(rv, 1.0); return rv; } @@ -85,7 +102,7 @@ inline F32 ll_internal_random<F32>() // Per Monty, it's important to clamp using the correct fmodf() rather // than expanding to F64 for fmod() and then truncating back to F32. Prior // to this change, we were getting sporadic ll_frand() == 1.0 results. - F32 rv{ narrow<F64>(gRandomGenerator()) }; + F32 rv{ narrow<F64>(ll_internal_get_rand()) }; if(!((rv >= 0.0f) && (rv < 1.0f))) return fmodf(rv, 1.0f); return rv; } |