Messages in this thread | | | Date | Mon, 28 Sep 2015 08:05:37 +0200 | From | Ingo Molnar <> | Subject | Re: [GIT PULL rcu/urgent] Fix two more 4.3 regressions |
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* Paul E. McKenney <paulmck@linux.vnet.ibm.com> wrote:
> Hello, Ingo, > > This series contains two small fixes for regressions introduced during > the past merge window: > > 1. Recent versions of gcc are fatally confused by use of a const > int variable for array bounds in inline functions, one of which > was introduced by 114b7fd4b (rcu: Create rcu_sync infrastructure). > For more information on the gcc bug, see: > > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67055#c13 > > This workaround for that gcc bug, courtesy of Oleg Nesterov, > simply substitutes the constant expression for the two uses of > the const int variable. > > 2. Commit 2cd6ffafec06 (rcu: Extend expedited funnel locking > to rcu_data structure) extended contention-reducing > funnel locking from the rcu_node structures to the rcu_data > structures, but failed to create a separate lock class for the > rcu_sched_data structures, which is needed due to the fact that > synchronize_rcu_expedited() invokes synchronize_sched_expedited(). > In the absence of this separate lock class, lockdep can give > false-positive splats. This commit therefore creates the > required lock class so that lockdep can see that there is in > fact no deadlock. > > Both fixes have been exposed to -next and 0day Test Robot testing. > > These changes are available in the git repository at: > > git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git for-mingo > > for you to fetch changes up to 19a5ecde086a6a5287978b12ae948fa691b197b7: > > rcu: Suppress lockdep false positive for rcp->exp_funnel_mutex (2015-09-20 21:01:22 -0700) > > ---------------------------------------------------------------- > Oleg Nesterov (1): > rcu: Change _wait_rcu_gp() to work around GCC bug 67055 > > Paul E. McKenney (1): > rcu: Suppress lockdep false positive for rcp->exp_funnel_mutex > > include/linux/rcupdate.h | 11 +++++------ > kernel/rcu/tree.c | 5 +++++ > 2 files changed, 10 insertions(+), 6 deletions(-)
Pulled, thanks a lot Paul!
Ingo
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