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The sched_add() function is not only used when the thread is initially

Description

The sched_add() function is not only used when the thread is initially
started, but also by the turnstiles to mark a thread as runnable for
all locks, for instance sleepqueues do:
setrunnable()->sched_wakeup()->sched_add()

In r326218 code was added to allow booting from non-zero CPU numbers
by setting the ts_cpu field inside the ULE scheduler's sched_add()
function. This had an undesired side-effect that prior sched_pin() and
sched_bind() calls got disregarded. This patch fixes the
initialization of the ts_cpu field for the ULE scheduler to only
happen once when the initial thread is constructed during system
init. Forking will then later on ensure that a valid ts_cpu value gets
copied to all children.

Reviewed by: jhb, kib
Discussed with: nwhitehorn
MFC after: 1 month
Differential revision: https://reviews.freebsd.org/D13298
Sponsored by: Mellanox Technologies

Details

Committed
hselaskyNov 29 2017, 11:28 PM
Reviewer
jhb
Differential Revision
D13298: Fix regression issue after r326218
Parents
rS326375: Don't fail the build due to clang integer constant range warnings
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