srcu: Remove needless rcu_seq_done() check while holding read lock

The srcu_gp_start_if_needed() function now read-holds the srcu_struct
whose grace period is being started, which means that the corresponding
SRCU grace period cannot end.  This in turn means that the SRCU
grace-period sequence number returned by rcu_seq_snap() cannot expire
during this time.  And that means that the calls to rcu_seq_done() in
srcu_funnel_exp_start() and srcu_funnel_gp_start() can never return true.

This commit therefore removes these rcu_seq_done() checks, but adds checks
in kernels built with CONFIG_PROVE_RCU=y that splats if rcu_seq_done()
does somehow return true.

[ paulmck: Rearrange checks to handle kernels built with lockdep. ]

Signed-off-by: Pingfan Liu <[email protected]>
Cc: Lai Jiangshan <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Josh Triplett <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
To: [email protected]
Signed-off-by: Paul E. McKenney <[email protected]>

0 files changed, 0 insertions, 0 deletions