power: extend guest channel API for reading

Added new experimental API rte_power_guest_channel_receive_msg
which gives possibility to receive messages send to guest.

Signed-off-by: Marcin Hajkowski <marcinx.hajkowski@intel.com>
Tested-by: David Hunt <david.hunt@intel.com>
Acked-by: Lee Daly <lee.daly@intel.com>

diff --git a/lib/librte_power/channel_commands.h b/lib/librte_power/channel_commands.h
index eca8ff7..d81216b 100644 (file)
--- a/lib/librte_power/channel_commands.h
+++ b/lib/librte_power/channel_commands.h
@@ -25,6 +25,11 @@ extern "C" {
 #define CPU_POWER_SCALE_MIN     4
 #define CPU_POWER_ENABLE_TURBO  5
 #define CPU_POWER_DISABLE_TURBO 6
+
+/* Generic Power Command Response */
+#define CPU_POWER_CMD_ACK       1
+#define CPU_POWER_CMD_NACK      2
+
 #define HOURS 24
 
 #define MAX_VFS 10

diff --git a/lib/librte_power/guest_channel.c b/lib/librte_power/guest_channel.c
index 9cf7d2c..8884238 100644 (file)
--- a/lib/librte_power/guest_channel.c
+++ b/lib/librte_power/guest_channel.c
@@ -10,6 +10,7 @@
 #include <fcntl.h>
 #include <string.h>
 #include <errno.h>
+#include <poll.h>
 
 
 #include <rte_log.h>
@@ -19,6 +20,9 @@
 
 #define RTE_LOGTYPE_GUEST_CHANNEL RTE_LOGTYPE_USER1
 
+/* Timeout for incoming message in milliseconds. */
+#define TIMEOUT 10
+
 static int global_fds[RTE_MAX_LCORE] = { [0 ... RTE_MAX_LCORE-1] = -1 };
 
 int
@@ -125,6 +129,62 @@ int rte_power_guest_channel_send_msg(struct channel_packet *pkt,
        return guest_channel_send_msg(pkt, lcore_id);
 }
 
+int power_guest_channel_read_msg(struct channel_packet *pkt,
+                       unsigned int lcore_id)
+{
+       int ret;
+       struct pollfd fds;
+       void *buffer = pkt;
+       int buffer_len = sizeof(*pkt);
+
+       fds.fd = global_fds[lcore_id];
+       fds.events = POLLIN;
+
+       ret = poll(&fds, 1, TIMEOUT);
+       if (ret == 0) {
+               RTE_LOG(DEBUG, GUEST_CHANNEL, "Timeout occurred during poll function.\n");
+               return -1;
+       } else if (ret < 0) {
+               RTE_LOG(ERR, GUEST_CHANNEL, "Error occurred during poll function: %s\n",
+                               strerror(ret));
+               return -1;
+       }
+
+       if (lcore_id >= RTE_MAX_LCORE) {
+               RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
+                               lcore_id, RTE_MAX_LCORE-1);
+               return -1;
+       }
+
+       if (global_fds[lcore_id] < 0) {
+               RTE_LOG(ERR, GUEST_CHANNEL, "Channel is not connected\n");
+               return -1;
+       }
+
+       while (buffer_len > 0) {
+               ret = read(global_fds[lcore_id],
+                               buffer, buffer_len);
+               if (ret < 0) {
+                       if (errno == EINTR)
+                               continue;
+                       return -1;
+               }
+               if (ret == 0) {
+                       RTE_LOG(ERR, GUEST_CHANNEL, "Expected more data, but connection has been closed.\n");
+                       return -1;
+               }
+               buffer = (char *)buffer + ret;
+               buffer_len -= ret;
+       }
+
+       return 0;
+}
+
+int rte_power_guest_channel_receive_msg(struct channel_packet *pkt,
+                       unsigned int lcore_id)
+{
+       return power_guest_channel_read_msg(pkt, lcore_id);
+}
 
 void
 guest_channel_host_disconnect(unsigned int lcore_id)

diff --git a/lib/librte_power/guest_channel.h b/lib/librte_power/guest_channel.h
index 373d398..61e1422 100644 (file)
--- a/lib/librte_power/guest_channel.h
+++ b/lib/librte_power/guest_channel.h
@@ -68,6 +68,42 @@ int guest_channel_send_msg(struct channel_packet *pkt, unsigned int lcore_id);
 int rte_power_guest_channel_send_msg(struct channel_packet *pkt,
                        unsigned int lcore_id);
 
+/**
+ * Read a message contained in pkt over the Virtio-Serial
+ * from the host endpoint.
+ *
+ * @param pkt
+ *  Pointer to a populated struct channel_packet
+ *
+ * @param lcore_id
+ *  lcore_id.
+ *
+ * @return
+ *  - 0 on success.
+ *  - Negative on error.
+ */
+int power_guest_channel_read_msg(struct channel_packet *pkt,
+               unsigned int lcore_id);
+
+/**
+ * Receive a message contained in pkt over the Virtio-Serial
+ * from the host endpoint.
+ *
+ * @param pkt
+ *  Pointer to a populated struct channel_packet
+ *
+ * @param lcore_id
+ *  lcore_id.
+ *
+ * @return
+ *  - 0 on success.
+ *  - Negative on error.
+ */
+__rte_experimental
+int
+rte_power_guest_channel_receive_msg(struct channel_packet *pkt,
+                       unsigned int lcore_id);
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/lib/librte_power/rte_power_version.map b/lib/librte_power/rte_power_version.map
index 0429173..7729838 100644 (file)
--- a/lib/librte_power/rte_power_version.map
+++ b/lib/librte_power/rte_power_version.map
@@ -42,6 +42,7 @@ EXPERIMENTAL {
        rte_power_empty_poll_stat_free;
        rte_power_empty_poll_stat_init;
        rte_power_empty_poll_stat_update;
+       rte_power_guest_channel_receive_msg;
        rte_power_poll_stat_fetch;
        rte_power_poll_stat_update;
 };