Re: [PATCH 2/5] netdevtap: Use common helper function to create unique tap name
On 12/4/20 2:01 AM, Shi Lei wrote:
Simplify GenerateName/ReserveName for netdevtap by using common
functions.
Signed-off-by: Shi Lei <shi_lei(a)massclouds.com>
---
src/util/virnetdevtap.c | 58 +++--------------------------------------
1 file changed, 4 insertions(+), 54 deletions(-)
diff --git a/src/util/virnetdevtap.c b/src/util/virnetdevtap.c
index 198607b5..38b2f171 100644
--- a/src/util/virnetdevtap.c
+++ b/src/util/virnetdevtap.c
@@ -55,9 +55,6 @@
VIR_LOG_INIT("util.netdevtap");
-virMutex virNetDevTapCreateMutex = VIR_MUTEX_INITIALIZER;
-static int virNetDevTapLastID = -1; /* not "unsigned" because callers use %d
*/
-
/**
* virNetDevTapReserveName:
@@ -72,25 +69,7 @@ static int virNetDevTapLastID = -1; /* not "unsigned"
because callers use %d */
void
virNetDevTapReserveName(const char *name)
{
- unsigned int id;
- const char *idstr = NULL;
-
-
- if (STRPREFIX(name, VIR_NET_GENERATED_TAP_PREFIX)) {
-
- VIR_INFO("marking device in use: '%s'", name);
-
- idstr = name + strlen(VIR_NET_GENERATED_TAP_PREFIX);
-
- if (virStrToLong_ui(idstr, NULL, 10, &id) >= 0) {
- virMutexLock(&virNetDevTapCreateMutex);
-
- if (virNetDevTapLastID < (int)id)
- virNetDevTapLastID = id;
-
- virMutexUnlock(&virNetDevTapCreateMutex);
- }
- }
+ virNetDevReserveName(name, VIR_NET_DEV_GEN_NAME_TAP, true);
I think we can just call virNetDevReserveName() directly, rather than
keeping virNetDevTapReserveName() as a go-between...
}
@@ -199,36 +178,7 @@ virNetDevTapGetRealDeviceName(char *ifname G_GNUC_UNUSED)
static int
virNetDevTapGenerateName(char **ifname)
{
- int id;
- double maxIDd = pow(10, IFNAMSIZ - 1 - strlen(VIR_NET_GENERATED_TAP_PREFIX));
- int maxID = INT_MAX;
- int attempts = 0;
-
- if (maxIDd <= (double)INT_MAX)
- maxID = (int)maxIDd;
-
- do {
- g_autofree char *try = NULL;
-
- id = ++virNetDevTapLastID;
-
- /* reset before overflow */
- if (virNetDevTapLastID >= maxID)
- virNetDevTapLastID = -1;
-
- try = g_strdup_printf(*ifname, id);
-
- if (!virNetDevExists(try)) {
- g_free(*ifname);
- *ifname = g_steal_pointer(&try);
- return 0;
- }
- } while (++attempts < 10000);
-
- virReportError(VIR_ERR_INTERNAL_ERROR,
- _("no unused %s names available"),
- VIR_NET_GENERATED_TAP_PREFIX);
- return -1;
+ return virNetDevGenerateName(ifname, VIR_NET_DEV_GEN_NAME_TAP);
Same here.
}
@@ -263,7 +213,7 @@ int virNetDevTapCreate(char **ifname,
int ret = -1;
int fd = -1;
- virMutexLock(&virNetDevTapCreateMutex);
+ virNetDevLockGenName(VIR_NET_DEV_GEN_NAME_TAP);
/* if ifname is "vnet%d", then auto-generate a name for the new
* device (the kernel could do this for us, but has a bad habit of
The code around here is going to need to be updated to take advantage of
the "g_strdup_printf(*ifname, id)" in your new Generate function. (as a
matter of fact, the functions that call virNetDevTapCreate() should
probably also be updated to stop them from adding in "vnet%d" when
ifname is empty - we can just let it remain empty until the call to
virNetDevGenerateName().
@@ -333,7 +283,7 @@ int virNetDevTapCreate(char **ifname,
ret = 0;
cleanup:
- virMutexUnlock(&virNetDevTapCreateMutex);
+ virNetDevUnlockGenName(VIR_NET_DEV_GEN_NAME_TAP);
if (ret < 0) {
VIR_FORCE_CLOSE(fd);
while (i--)