2013-08-06 18:55:46

by Olaf Hering

[permalink] [raw]
Subject: [PATCH] Tools: hv: use single send+recv buffer

send_buffer is used only once during registration. To reduce runtime
memory usage reuse the recv_buffer for registration. Also use
NLMSG_LENGTH instead of NLMSG_HDRLEN to take alignment into account.

Signed-off-by: Olaf Hering <[email protected]>
---
tools/hv/hv_kvp_daemon.c | 10 ++++------
tools/hv/hv_vss_daemon.c | 8 +++-----
2 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c
index 6a31ca0..d3bcb84 100644
--- a/tools/hv/hv_kvp_daemon.c
+++ b/tools/hv/hv_kvp_daemon.c
@@ -1439,7 +1439,6 @@ int main(void)
int pool;
char *if_name;
struct hv_kvp_ipaddr_value *kvp_ip_val;
- char *kvp_send_buffer;
char *kvp_recv_buffer;
size_t kvp_recv_buffer_len;

@@ -1448,11 +1447,10 @@ int main(void)
openlog("KVP", 0, LOG_USER);
syslog(LOG_INFO, "KVP starting; pid is:%d", getpid());

- kvp_recv_buffer_len = NLMSG_HDRLEN + sizeof(struct cn_msg) + sizeof(struct hv_kvp_msg);
- kvp_send_buffer = calloc(1, kvp_recv_buffer_len);
+ kvp_recv_buffer_len = NLMSG_LENGTH(0) + sizeof(struct cn_msg) + sizeof(struct hv_kvp_msg);
kvp_recv_buffer = calloc(1, kvp_recv_buffer_len);
- if (!(kvp_send_buffer && kvp_recv_buffer)) {
- syslog(LOG_ERR, "Failed to allocate netlink buffers");
+ if (!kvp_recv_buffer) {
+ syslog(LOG_ERR, "Failed to allocate netlink buffer");
exit(EXIT_FAILURE);
}
/*
@@ -1494,7 +1492,7 @@ int main(void)
/*
* Register ourselves with the kernel.
*/
- message = (struct cn_msg *)kvp_send_buffer;
+ message = (struct cn_msg *)kvp_recv_buffer;
message->id.idx = CN_KVP_IDX;
message->id.val = CN_KVP_VAL;

diff --git a/tools/hv/hv_vss_daemon.c b/tools/hv/hv_vss_daemon.c
index 4c34675..6b4f2fa 100644
--- a/tools/hv/hv_vss_daemon.c
+++ b/tools/hv/hv_vss_daemon.c
@@ -145,7 +145,6 @@ int main(void)
struct cn_msg *incoming_cn_msg;
int op;
struct hv_vss_msg *vss_msg;
- char *vss_send_buffer;
char *vss_recv_buffer;
size_t vss_recv_buffer_len;

@@ -155,10 +154,9 @@ int main(void)
openlog("Hyper-V VSS", 0, LOG_USER);
syslog(LOG_INFO, "VSS starting; pid is:%d", getpid());

- vss_recv_buffer_len = NLMSG_HDRLEN + sizeof(struct cn_msg) + sizeof(struct hv_vss_msg);
- vss_send_buffer = calloc(1, vss_recv_buffer_len);
+ vss_recv_buffer_len = NLMSG_LENGTH(0) + sizeof(struct cn_msg) + sizeof(struct hv_vss_msg);
vss_recv_buffer = calloc(1, vss_recv_buffer_len);
- if (!(vss_send_buffer && vss_recv_buffer)) {
+ if (!vss_recv_buffer) {
syslog(LOG_ERR, "Failed to allocate netlink buffers");
exit(EXIT_FAILURE);
}
@@ -185,7 +183,7 @@ int main(void)
/*
* Register ourselves with the kernel.
*/
- message = (struct cn_msg *)vss_send_buffer;
+ message = (struct cn_msg *)vss_recv_buffer;
message->id.idx = CN_VSS_IDX;
message->id.val = CN_VSS_VAL;
message->ack = 0;