[Qemu-devel] [PULL 01/20] net/tap: Allocating Large sized arrays to heap

[Jason Wang <jasowang@redhat.com>]

From: Zhou Jie <zhoujie2011@cn.fujitsu.com>

net_init_tap has a huge stack usage of 8192 bytes approx.
Moving large arrays to heap to reduce stack usage.

Signed-off-by: Zhou Jie <zhoujie2011@cn.fujitsu.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 net/tap.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/tap.c b/net/tap.c
index 740e8a2..49817c7 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -769,8 +769,8 @@ int net_init_tap(const NetClientOptions *opts, const char *name,
             return -1;
         }
     } else if (tap->has_fds) {
-        char *fds[MAX_TAP_QUEUES];
-        char *vhost_fds[MAX_TAP_QUEUES];
+        char **fds = g_new(char *, MAX_TAP_QUEUES);
+        char **vhost_fds = g_new(char *, MAX_TAP_QUEUES);
         int nfds, nvhosts;
 
         if (tap->has_ifname || tap->has_script || tap->has_downscript ||
@@ -818,6 +818,8 @@ int net_init_tap(const NetClientOptions *opts, const char *name,
                 return -1;
             }
         }
+        g_free(fds);
+        g_free(vhost_fds);
     } else if (tap->has_helper) {
         if (tap->has_ifname || tap->has_script || tap->has_downscript ||
             tap->has_vnet_hdr || tap->has_queues || tap->has_vhostfds) {
-- 
2.7.4