[PATCH 2/6] powerpc/pseries: add missing of_node_put

From: Julia Lawall
Date: Fri Nov 20 2015 - 15:45:31 EST


for_each_node_by_type performs an of_node_get on each iteration, so a break
out of the loop requires an of_node_put. In this code, there are two paths
that break out of the loop. In the first one (open-pic case), the code
originally contained an of_node_get. That increments the reference count,
which cancels out against the decrement of the reference count that is
needed here, and thus the patch drops the of_node_get. In the second one
(ppc-xicp case), there is no need to save the node value, and so an
of_node_put is added as described by the following semantic patch rule
(http://coccinelle.lip6.fr):

// <smpl>
@@
expression e,e1;
local idexpression n;
@@

for_each_node_by_type(n, e1) {
... when != of_node_put(n)
when != e = n
(
return n;
|
+ of_node_put(n);
? return ...;
)
...
}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxx>

---
arch/powerpc/platforms/pseries/setup.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 36df46e..7185cd3 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -236,7 +236,7 @@ static void __init pseries_discover_pic(void)
for_each_node_by_name(np, "interrupt-controller") {
typep = of_get_property(np, "compatible", NULL);
if (strstr(typep, "open-pic")) {
- pSeries_mpic_node = of_node_get(np);
+ pSeries_mpic_node = np;
ppc_md.init_IRQ = pseries_mpic_init_IRQ;
setup_kexec_cpu_down_mpic();
smp_init_pseries_mpic();
@@ -245,6 +245,7 @@ static void __init pseries_discover_pic(void)
ppc_md.init_IRQ = pseries_xics_init_IRQ;
setup_kexec_cpu_down_xics();
smp_init_pseries_xics();
+ of_node_put(np);
return;
}
}

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