[PATCH v4 2/3] handle pps limit parameter

[William Dauchy <william@gandi.net>]

adapt libxl to handle pps limit parameter
the new pps limit can be defined using a '&' symbol after
the rate limit for example:
YYMb/s&XXKpps@ZZms
or
YYMb/s@ZZms&XXKpps
or
YYMb/s&XXKpps in such case default 50ms interval will be used

Signed-off-by: Ahmed Amamou <ahmed@gandi.net>
Signed-off-by: William Dauchy <william@gandi.net>
Signed-off-by: Kamel Haddadou <kamel@gandi.net>
---
 tools/libxl/libxl.c         |    3 ++
 tools/libxl/libxl_types.idl |    1 +
 tools/libxl/libxlu_vif.c    |   70 +++++++++++++++++++++++++++++++++++++++++--
 3 files changed, 71 insertions(+), 3 deletions(-)

diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
index 3236aa9..11572bc 100644
--- a/tools/libxl/libxl.c
+++ b/tools/libxl/libxl.c
@@ -2920,6 +2920,9 @@ void libxl__device_nic_add(libxl__egc *egc, uint32_t domid,
         flexarray_append(back, libxl__sprintf(gc, "%"PRIu64",%"PRIu32"",
                             nic->rate_bytes_per_interval,
                             nic->rate_interval_usecs));
+        flexarray_append(back, "pps");
+        flexarray_append(back, libxl__sprintf(gc, "%"PRIu64"",
+                            nic->rate_packets_per_interval));
     }
 
     flexarray_append(back, "bridge");
diff --git a/tools/libxl/libxl_types.idl b/tools/libxl/libxl_types.idl
index d218a2d..be2ae94 100644
--- a/tools/libxl/libxl_types.idl
+++ b/tools/libxl/libxl_types.idl
@@ -390,6 +390,7 @@ libxl_device_nic = Struct("device_nic", [
     ("script", string),
     ("nictype", libxl_nic_type),
     ("rate_bytes_per_interval", uint64),
+    ("rate_packets_per_interval", uint64),
     ("rate_interval_usecs", uint32),
     ("gatewaydev", string),
     ])
diff --git a/tools/libxl/libxlu_vif.c b/tools/libxl/libxlu_vif.c
index 3b3de0f..3d491d8 100644
--- a/tools/libxl/libxlu_vif.c
+++ b/tools/libxl/libxlu_vif.c
@@ -3,6 +3,7 @@
 
 static const char *vif_bytes_per_sec_re = "^[0-9]+[GMK]?[Bb]/s$";
 static const char *vif_internal_usec_re = "^[0-9]+[mu]?s?$";
+static const char *vif_packets_per_sec_re = "^[0-9]+[GMK]?pps$";
 
 static void xlu__vif_err(XLU_Config *cfg, const char *msg, const char *rate) {
     fprintf(cfg->report,
@@ -49,6 +50,43 @@ out:
     return rc;
 }
 
+static int vif_parse_rate_packets_per_sec(XLU_Config *cfg, const char *packet,
+                                        uint64_t *packets_per_sec)
+{
+    regex_t rec;
+    uint64_t tmp = 0;
+    const char *p;
+    int rc = 0;
+
+    regcomp(&rec, vif_packets_per_sec_re, REG_EXTENDED|REG_NOSUB);
+    if (regexec(&rec, packet, 0, NULL, 0)) {
+        xlu__vif_err(cfg, "invalid pps", packet);
+        rc = EINVAL;
+        goto out;
+    }
+
+    p = packet;
+    tmp = strtoull(p, (char**)&p, 0);
+    if (tmp == 0 || tmp > UINT32_MAX || errno == ERANGE) {
+        xlu__vif_err(cfg, "pps overflow", packet);
+        rc = EOVERFLOW;
+        goto out;
+    }
+
+    if (*p == 'G')
+       tmp *= 1000 * 1000 * 1000;
+    else if (*p == 'M')
+       tmp *= 1000 * 1000;
+    else if (*p == 'K')
+       tmp *= 1000;
+
+    *packets_per_sec = tmp;
+
+out:
+    regfree(&rec);
+    return rc;
+}
+
 static int vif_parse_rate_interval_usecs(XLU_Config *cfg, const char *interval,
                                          uint32_t *interval_usecs)
 {
@@ -94,22 +132,35 @@ int xlu_vif_parse_rate(XLU_Config *cfg, const char *rate, libxl_device_nic *nic)
 {
     uint64_t bytes_per_sec = 0;
     uint64_t bytes_per_interval = 0;
+    uint64_t packets_per_sec = 0;
+    uint64_t packets_per_interval = 0;
     uint32_t interval_usecs = 50000UL; /* Default to 50ms */
-    char *ratetok, *tmprate;
+    char *ratetok, *tmprate, *tmp_pps, *tmpint;
     int rc = 0;
 
+    /* rate string need to be duplicated because strtok may change it */
     tmprate = strdup(rate);
+    tmp_pps = strdup(rate);
+    tmpint = strdup(rate);
+
     if (!strcmp(tmprate,"")) {
         xlu__vif_err(cfg, "no rate specified", rate);
         rc = EINVAL;
         goto out;
     }
 
-    ratetok = strtok(tmprate, "@");
+    /* accepted rate string are as follow:
+     * rate&pps@interval or rate@interval&pps
+     */
+
+    /* ratetok contains the first token */
+    ratetok = strtok(tmprate, "@&");
     rc = vif_parse_rate_bytes_per_sec(cfg, ratetok, &bytes_per_sec);
     if (rc) goto out;
 
-    ratetok = strtok(NULL, "@");
+    ratetok = strtok(tmpint, "@");
+    ratetok = strtok(NULL, "@&");
+    /* ratetok contains the first token following the '@' */
     if (ratetok != NULL) {
         rc = vif_parse_rate_interval_usecs(cfg, ratetok, &interval_usecs);
         if (rc) goto out;
@@ -121,14 +172,27 @@ int xlu_vif_parse_rate(XLU_Config *cfg, const char *rate, libxl_device_nic *nic)
         goto out;
     }
 
+    ratetok = strtok(tmp_pps, "&");
+    ratetok = strtok(NULL, "&@");
+    /* ratetok contains the first token following the '&' */
+    if (ratetok != NULL) {
+        rc = vif_parse_rate_packets_per_sec(cfg, ratetok, &packets_per_sec);
+        if (rc) goto out;
+    }
+
     bytes_per_interval =
         (((uint64_t) bytes_per_sec * (uint64_t) interval_usecs) / 1000000UL);
+    packets_per_interval =
+        (((uint64_t) packets_per_sec * (uint64_t) interval_usecs) / 1000000UL);
 
     nic->rate_interval_usecs = interval_usecs;
     nic->rate_bytes_per_interval = bytes_per_interval;
+    nic->rate_packets_per_interval = packets_per_interval;
 
 out:
     free(tmprate);
+    free(tmp_pps);
+    free(tmpint);
     return rc;
 }
 
-- 
1.7.9.5