Optimise use of Giant in the LinuxKPI.

- Make sure Giant is locked when calling PCI device methods.
Newbus currently requires this.

- Avoid unlocking Giant right before aquiring the sleepqueue lock.
This can save a task switch.

MFC after:	1 week
Sponsored by:	Mellanox Technologies

1 files changed, 2 insertions, 2 deletions

diff --git a/sys/compat/linuxkpi/common/src/linux_rcu.c b/sys/compat/linuxkpi/common/src/linux_rcu.c
index 0ece0342aad5..c565d85724bd 100644
--- a/sys/compat/linuxkpi/common/src/linux_rcu.c
+++ b/sys/compat/linuxkpi/common/src/linux_rcu.c
@@ -297,14 +297,14 @@ linux_synchronize_rcu(void)
 
 	td = curthread;
 
-	DROP_GIANT();
-
 	/*
 	 * Synchronizing RCU might change the CPU core this function
 	 * is running on. Save current values:
 	 */
 	thread_lock(td);
 
+	DROP_GIANT();
+
 	old_cpu = PCPU_GET(cpuid);
 	old_pinned = td->td_pinned;
 	old_prio = td->td_priority;