diff options
| author | Paul E. McKenney <paul.mckenney@linaro.org> | 2012-01-10 14:23:29 -0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2012-02-21 09:03:37 -0800 |
| commit | 8146c4e2e2c1972216afece5c50e072e86120e42 (patch) | |
| tree | df8707527f59534595edb0be4f69255d4dff40c8 /kernel/rcutree.c | |
| parent | 778d250a29224795e6320b58928bafa6b6104a06 (diff) | |
| download | lwn-8146c4e2e2c1972216afece5c50e072e86120e42.tar.gz lwn-8146c4e2e2c1972216afece5c50e072e86120e42.zip | |
rcu: Check for callback invocation from offline CPUs
Because quiescent states are now reported from offline CPUs in
CPU_DYING state, there is some possibility that such a CPU might
note the end of a grace period and attempt to start invoking
callbacks. This would be a very bad thing, and is supposed to
be prevented by the fact that the CPU_DYING CPU gets rid of all
its callbacks before reporting the quiescent state. However,
there is other CPU-offline code in the kernel, and it is quite
possible that someone will invoke RCU core processing from that
code. Therefore, this commit adds a warning for this case.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/rcutree.c')
| -rw-r--r-- | kernel/rcutree.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/rcutree.c b/kernel/rcutree.c index 575f91d03f06..ac3a810d2db7 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -1373,6 +1373,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp) * races with call_rcu() from interrupt handlers. */ local_irq_save(flags); + WARN_ON_ONCE(cpu_is_offline(smp_processor_id())); bl = rdp->blimit; trace_rcu_batch_start(rsp->name, rdp->qlen_lazy, rdp->qlen, bl); list = rdp->nxtlist; |