[PATCH] lockdep: irqtrace subsystem, move account_system_vtime() calls into kernel/softirq.c

At the moment, powerpc and s390 have their own versions of do_softirq which
include local_bh_disable() and __local_bh_enable() calls.  They end up
calling __do_softirq (in kernel/softirq.c) which also does
local_bh_disable/enable.

Apparently the two levels of disable/enable trigger a warning from some
validation code that Ingo is working on, and he would like to see the outer
level removed.  But to do that, we have to move the account_system_vtime
calls that are currently in the arch do_softirq() implementations for
powerpc and s390 into the generic __do_softirq() (this is a no-op for other
archs because account_system_vtime is defined to be an empty inline
function on all other archs).  This patch does that.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 5 insertions, 14 deletions

diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 027728b95429..e3774f6b57cc 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -424,13 +424,8 @@ void do_softirq(void)
 
         local_irq_save(flags);
 
-        if (local_softirq_pending()) {
-                account_system_vtime(current);
-                local_bh_disable();
+        if (local_softirq_pending())
                 do_softirq_onstack();
-                account_system_vtime(current);
-                _local_bh_enable();
-        }
 
         local_irq_restore(flags);
 }
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index e347190d9aea..1eef50918615 100644
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -69,10 +69,6 @@ asmlinkage void do_softirq(void)
 
         local_irq_save(flags);
 
-        account_system_vtime(current);
-
-        local_bh_disable();
-
         if (local_softirq_pending()) {
                 /* Get current stack pointer. */
                 asm volatile("la %0,0(15)" : "=a" (old));
@@ -95,10 +91,6 @@ asmlinkage void do_softirq(void)
                         __do_softirq();
         }
 
-        account_system_vtime(current);
-
-        _local_bh_enable();
-
         local_irq_restore(flags);
 }
 
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 584609b6a66e..215541e26c1a 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -193,6 +193,8 @@ asmlinkage void __do_softirq(void)
         int cpu;
 
         pending = local_softirq_pending();
+        account_system_vtime(current);
+
         __local_bh_disable((unsigned long)__builtin_return_address(0));
         trace_softirq_enter();
 
@@ -224,6 +226,8 @@ restart:
                 wakeup_softirqd();
 
         trace_softirq_exit();
+
+        account_system_vtime(current);
         _local_bh_enable();
 }