Re: Is there any way to request unique lwlock inside a backgroundworker in PG9.4? - Mailing list pgsql-hackers

From Hubert Zhang
Subject Re: Is there any way to request unique lwlock inside a backgroundworker in PG9.4?
Date
Msg-id CAB0yrenA9OAdV=hFdaRcaaAriaL+iB8AoGxRA62zNxknPnHD+w@mail.gmail.com
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In response to Re: Is there any way to request unique lwlock inside a backgroundworker in PG9.4?  (Andres Freund <andres@anarazel.de>)
List pgsql-hackers
Thanks a lot. 

On Wed, Oct 17, 2018 at 11:21 PM Andres Freund <andres@anarazel.de> wrote:
Hi,

On 2018-10-17 23:11:26 +0800, Hubert Zhang wrote:
> The section "Share Memory and LWLocks" describe the AddinShmemInitLock which
> is used to protect the ShmemInitStruct() when backend workers initialize
> their shm.  My requirement is to how to protect the shm access within the
> bgworkers(not at init stage). This lock should be bgworkers specific.

Rereead the page please. After you RequestAddinLWLocks() during
initialization, you can use LWLockAssign() to get an lwlock. Which you
then can use as is your pleasure.

Greetings,

Andres Freund


--
Thanks

Hubert Zhang

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