Don't count internal ApplicationCallbackExecCtx against ExcCtx count#17973
Merged
ericgribkoff merged 2 commits intogrpc:masterfrom Feb 9, 2019
Merged
Don't count internal ApplicationCallbackExecCtx against ExcCtx count#17973ericgribkoff merged 2 commits intogrpc:masterfrom
ericgribkoff merged 2 commits intogrpc:masterfrom
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This was originally done for ExcCtx in grpc#15825. This avoids a hang in our pre-fork handler, where grpc_core::Executor::RunClosures attempts to increment the thread count from an invocation of grpc_prefork():
vjpai
reviewed
Feb 8, 2019
src/core/lib/iomgr/exec_ctx.h
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| static void GlobalShutdown(void) { gpr_tls_destroy(&callback_exec_ctx_); } | ||
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| private: | ||
| uintptr_t flags_; |
Contributor
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flags_{0} will solve your MSAN issues
vjpai
approved these changes
Feb 9, 2019
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Thanks @vjpai! |
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This was originally done for ExcCtx in
#15825. This avoids a hang in our
pre-fork handler, where grpc_core::Executor::RunClosures attempts to
increment the thread count from an invocation of grpc_prefork().
The stack trace of the hang without this change:
At least one other option besides the
GRPC_APP_CALLBACK_EXEC_CTX_FLAG_IS_INTERNAL_THREADflag introduced here is to look at the existing excctx and inherit whether to increment/decrement the thread count based on its setting. But it's not clear to me that an ApplicationCallbackExecCtx will always be created with an associated ExecCtx - in which case the increment/decrement calls may be suitable to delete altogether.As for why this wasn't caught by our test infrastructure: this was an oversight on my part, and I'm reviving #16513 to make sure we have test coverage for this in the future.