tree 82deb50b4a92e7d8ea3d6aa6e69d5cc765487d1c
parent fc6eea4de24fbefa24115fb0b51f629b742da1e2
author Willy Tarreau <w@1wt.eu> 1516861333 +0100
committer Willy Tarreau <w@1wt.eu> 1517238445 +0100
encoding latin1

MINOR: fd: pass the iocb and owner to fd_insert()

fd_insert() is currently called just after setting the owner and iocb,
but proceeding like this prevents the operation from being atomic and
requires a lock to protect the maxfd computation in another thread from
meeting an incompletely initialized FD and computing a wrong maxfd.
Fortunately for now all fdtab[].owner are set before calling fd_insert(),
and the first lock in fd_insert() enforces a memory barrier so the code
is safe.

This patch moves the initialization of the owner and iocb to fd_insert()
so that the function will be able to properly arrange its operations and
remain safe even when modified to become lockless. There's no other change
beyond the internal API.