On 05-May-20 11:25 AM, Burakov, Anatoly wrote:
On 03-May-20 5:26 PM, Renata Saiakhova wrote:
Free previously allocated memzone for HW rings
Signed-off-by: Renata Saiakhova <renata.saiakh...@ekinops.com>
---
lib/librte_ethdev/rte_ethdev.c | 23 +++++++++++++++++++++++
lib/librte_ethdev/rte_ethdev_driver.h | 14 ++++++++++++++
lib/librte_ethdev/rte_ethdev_version.map | 1 +
3 files changed, 38 insertions(+)
diff --git a/lib/librte_ethdev/rte_ethdev.c
b/lib/librte_ethdev/rte_ethdev.c
index 72aed59a5..c6d27e1aa 100644
--- a/lib/librte_ethdev/rte_ethdev.c
+++ b/lib/librte_ethdev/rte_ethdev.c
@@ -4206,6 +4206,29 @@ rte_eth_dma_zone_reserve(const struct
rte_eth_dev *dev, const char *ring_name,
RTE_MEMZONE_IOVA_CONTIG, align);
}
+int
+rte_eth_dma_zone_free(const struct rte_eth_dev *dev, const char
*ring_name,
+ uint16_t queue_id)
+{
+ char z_name[RTE_MEMZONE_NAMESIZE];
+ const struct rte_memzone *mz;
+ int rc = 0;
+
+ snprintf(z_name, sizeof(z_name), "eth_p%d_q%d_%s",
+ dev->data->port_id, queue_id, ring_name);
+ if (rc >= RTE_MEMZONE_NAMESIZE) {
+ RTE_ETHDEV_LOG(ERR, "ring name too long\n");
+ rte_errno = ENAMETOOLONG;
+ return NULL;
+ }
+
+ mz = rte_memzone_lookup(z_name);
+ if (mz)
+ rc = rte_memzone_free(mz);
This is racy. Please just use rte_memzone_free() unconditionally. It'll
return 0 if memzone existed, or will set rte_errno to EINVAL if it
didn't. (this is suboptimal, it should be ENOENT, but changing this
would be an API break... I'll submit a patch for future release to fix
this)
My apologies, just using rte_memzone_free will not solve the problem
because you don't have memzone pointer. Now that i think of it, the
rte_eth_dma_zone_reserve() suffers from this issue too, and the problem
is lack of atomic "find or create" memzone API.
This patch is OK for now, as it follows similar code in
rte_eth_dma_zone_reserve(), but ideally, this should be fixed at the
memzone API level. I'll see if i can cobble together a quick patchset
adding atomic "find or reserve" and "find and free" operations.
--
Thanks,
Anatoly
