diff mbox series

app/testpmd: support Tx mbuf free on demand cmd

Message ID 1614929583-37727-1-git-send-email-oulijun@huawei.com (mailing list archive)
State Superseded
Delegated to: Ferruh Yigit
Headers show
Series app/testpmd: support Tx mbuf free on demand cmd | expand

Checks

Context Check Description
ci/Intel-compilation fail Compilation issues
ci/Performance-Testing fail build patch failure
ci/checkpatch success coding style OK

Commit Message

Lijun Ou March 5, 2021, 7:33 a.m. UTC
From: Chengwen Feng <fengchengwen@huawei.com>

This patch support tx_done_cleanup command:
tx_done_cleanup port (port_id) (queue_id) (free_cnt)

User must make sure there are no concurrent access to the same Tx
queue (like rte_eth_tx_burst, rte_eth_dev_tx_queue_stop and so on)
when this command executed.

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Signed-off-by: Lijun Ou <oulijun@huawei.com>
---
 app/test-pmd/cmdline.c                      | 91 +++++++++++++++++++++++++++++
 doc/guides/rel_notes/release_21_05.rst      |  2 +
 doc/guides/testpmd_app_ug/testpmd_funcs.rst |  7 +++
 3 files changed, 100 insertions(+)

Comments

Li, Xiaoyun March 5, 2021, 7:46 a.m. UTC | #1
Hi
Sorry, forgot to send this in last patchset.

> -----Original Message-----
> From: Lijun Ou <oulijun@huawei.com>
> Sent: Friday, March 5, 2021 15:33
> To: Yigit, Ferruh <ferruh.yigit@intel.com>
> Cc: Li, Xiaoyun <xiaoyun.li@intel.com>; dev@dpdk.org;
> linuxarm@openeuler.org
> Subject: [PATCH] app/testpmd: support Tx mbuf free on demand cmd
> 
> From: Chengwen Feng <fengchengwen@huawei.com>
> 
> This patch support tx_done_cleanup command:
> tx_done_cleanup port (port_id) (queue_id) (free_cnt)
> 
> User must make sure there are no concurrent access to the same Tx queue (like
> rte_eth_tx_burst, rte_eth_dev_tx_queue_stop and so on) when this command

Users ...... this command is executed.

> executed.
> 
> Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
> Signed-off-by: Lijun Ou <oulijun@huawei.com>
> ---
>  app/test-pmd/cmdline.c                      | 91 +++++++++++++++++++++++++++++
>  doc/guides/rel_notes/release_21_05.rst      |  2 +
>  doc/guides/testpmd_app_ug/testpmd_funcs.rst |  7 +++
>  3 files changed, 100 insertions(+)
> 
> diff --git a/app/test-pmd/cmdline.c b/app/test-pmd/cmdline.c index
> 14110eb..832ae70 100644
> --- a/app/test-pmd/cmdline.c
> +++ b/app/test-pmd/cmdline.c
> @@ -36,6 +36,7 @@
>  #include <rte_pci.h>
>  #include <rte_ether.h>
>  #include <rte_ethdev.h>
> +#include <rte_ethdev_driver.h>
>  #include <rte_string_fns.h>
>  #include <rte_devargs.h>
>  #include <rte_flow.h>
> @@ -675,6 +676,9 @@ static void cmd_help_long_parsed(void *parsed_result,
>  			"set port (port_id) ptype_mask (ptype_mask)\n"
>  			"    set packet types classification for a specific
> port\n\n"
> 
> +			"tx_done_cleanup (port_id) (queue_id) (free_cnt)\n"
> +			"    Cleanup a tx queue's mbuf on a port\n\n"
> +
>  			"set port (port_id) queue-region region_id (value) "
>  			"queue_start_index (value) queue_num (value)\n"
>  			"    Set a queue region on a port\n\n"
> @@ -16910,6 +16914,92 @@ cmdline_parse_inst_t cmd_showport_macs = {
>  	},
>  };
> 
> +/* *** tx_done_cleanup *** */
> +struct cmd_tx_done_cleanup_result {
> +	cmdline_fixed_string_t clean;
> +	cmdline_fixed_string_t port;
> +	uint16_t port_id;
> +	uint16_t queue_id;
> +	uint32_t free_cnt;
> +};
> +
> +static void
> +cmd_tx_done_cleanup_parsed(void *parsed_result,
> +			   __rte_unused struct cmdline *cl,
> +			   __rte_unused void *data)
> +{
> +	struct cmd_tx_done_cleanup_result *res = parsed_result;
> +	struct rte_eth_dev *dev;
> +	uint16_t port_id = res->port_id;
> +	uint16_t queue_id = res->queue_id;
> +	uint32_t free_cnt = res->free_cnt;
> +	int ret;
> +
> +	if (!rte_eth_dev_is_valid_port(port_id)) {
> +		printf("Invalid port_id %u\n", port_id);
> +		return;
> +	}
> +
> +	dev = &rte_eth_devices[port_id];
> +	if (queue_id >= dev->data->nb_tx_queues) {
> +		printf("Invalid TX queue_id %u\n", queue_id);

Tx? You just want to send a patch to use Rx/Tx. You should keep concurrency.

> +		return;
> +	}
> +
> +	if (dev->data->tx_queue_state[queue_id] !=
> +		RTE_ETH_QUEUE_STATE_STARTED) {
> +		printf("TX queue_id %u not started!\n", queue_id);

Tx?

> +		return;
> +	}
> +
> +	/*
> +	 * rte_eth_tx_done_cleanup is a dataplane API, user must make sure
> +	 * there are no concurrent access to the same Tx queue (like
> +	 * rte_eth_tx_burst, rte_eth_dev_tx_queue_stop and so on) when this
> API
> +	 * called.
> +	 */

And I have some concerns on this. Users cannot know about this unless they read your code. I don't think this will likely happen.
So you should document this in testpmd doc when you introduced this command.

Or maybe you can have a way to stop that to happen. Maybe checking "test_done && engine != rxonly" before this?
In your comment, the tx forwarding shouldn't happen, right? Every fwd engine except rxonly will contain tx.
Well, it's still a rough way because tx may not happen even if it's io fwd.

Maybe other people have better ideas. Otherwise, you should at least document it.
@Yigit, Ferruh What do you think? Is there a better way?

> +	ret = rte_eth_tx_done_cleanup(port_id, queue_id, free_cnt);
> +	if (ret < 0) {
> +		printf("Failed to cleanup mbuf for port %u TX queue %u "

Tx?

> +		       "error desc: %s(%d)\n",
> +		       port_id, queue_id, strerror(-ret), ret);
> +		return;
> +	}
> +
> +	printf("Cleanup port %u TX queue %u mbuf nums: %u\n",

Tx?

> +	       port_id, queue_id, ret);
> +}
> +
> +cmdline_parse_token_string_t cmd_tx_done_cleanup_clean =
> +	TOKEN_STRING_INITIALIZER(struct cmd_tx_done_cleanup_result, clean,
> +				 "tx_done_cleanup");
> +cmdline_parse_token_string_t cmd_tx_done_cleanup_port =
> +	TOKEN_STRING_INITIALIZER(struct cmd_tx_done_cleanup_result, port,
> +				 "port");
> +cmdline_parse_token_num_t cmd_tx_done_cleanup_port_id =
> +	TOKEN_NUM_INITIALIZER(struct cmd_tx_done_cleanup_result, port_id,
> +			      UINT16);
> +cmdline_parse_token_num_t cmd_tx_done_cleanup_queue_id =
> +	TOKEN_NUM_INITIALIZER(struct cmd_tx_done_cleanup_result,
> queue_id,
> +			      UINT16);
> +cmdline_parse_token_num_t cmd_tx_done_cleanup_free_cnt =
> +	TOKEN_NUM_INITIALIZER(struct cmd_tx_done_cleanup_result,
> free_cnt,
> +			      UINT32);
> +
> +cmdline_parse_inst_t cmd_tx_done_cleanup = {
> +	.f = cmd_tx_done_cleanup_parsed,
> +	.data = NULL,
> +	.help_str = "tx_done_cleanup port <port_id> <queue_id> <free_cnt>",
> +	.tokens = {
> +		(void *)&cmd_tx_done_cleanup_clean,
> +		(void *)&cmd_tx_done_cleanup_port,
> +		(void *)&cmd_tx_done_cleanup_port_id,
> +		(void *)&cmd_tx_done_cleanup_queue_id,
> +		(void *)&cmd_tx_done_cleanup_free_cnt,
> +		NULL,
> +	},
> +};
> +
>  /*
> *****************************************************************
> *************** */
> 
>  /* list of instructions */
> @@ -17035,6 +17125,7 @@ cmdline_parse_ctx_t main_ctx[] = {
>  	(cmdline_parse_inst_t *)&cmd_config_rss_reta,
>  	(cmdline_parse_inst_t *)&cmd_showport_reta,
>  	(cmdline_parse_inst_t *)&cmd_showport_macs,
> +	(cmdline_parse_inst_t *)&cmd_tx_done_cleanup,
>  	(cmdline_parse_inst_t *)&cmd_config_burst,
>  	(cmdline_parse_inst_t *)&cmd_config_thresh,
>  	(cmdline_parse_inst_t *)&cmd_config_threshold, diff --git
> a/doc/guides/rel_notes/release_21_05.rst
> b/doc/guides/rel_notes/release_21_05.rst
> index 23f7f0b..8077573 100644
> --- a/doc/guides/rel_notes/release_21_05.rst
> +++ b/doc/guides/rel_notes/release_21_05.rst
> @@ -69,6 +69,8 @@ New Features
> 
>    * Added command to display Rx queue used descriptor count.
>      ``show port (port_id) rxq (queue_id) desc used count``
> +  * Added command to cleanup a Tx queue's mbuf on a port.
> +    ``tx_done_cleanup port <port_id> <queue_id> <free_cnt>``
> 
> 
>  Removed Items
> diff --git a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> index f59eb8a..39281f5 100644
> --- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> +++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> @@ -272,6 +272,13 @@ and ready to be processed by the driver on a given RX
> queue::
> 
>     testpmd> show port (port_id) rxq (queue_id) desc used count
> 
> +cleanup txq mbufs
> +~~~~~~~~~~~~~~~~~~~~~~~~
> +
> +Request the driver to free mbufs currently cached by the driver for a
> +given port's Tx queue::
> +   testpmd> tx_done_cleanup port (port_id) (queue_id) (free_cnt)
> +
>  show config
>  ~~~~~~~~~~~
> 
> --
> 2.7.4
Lijun Ou March 5, 2021, 9:58 a.m. UTC | #2
在 2021/3/5 15:46, Li, Xiaoyun 写道:
> Hi
> Sorry, forgot to send this in last patchset.
>
>> -----Original Message-----
>> From: Lijun Ou <oulijun@huawei.com>
>> Sent: Friday, March 5, 2021 15:33
>> To: Yigit, Ferruh <ferruh.yigit@intel.com>
>> Cc: Li, Xiaoyun <xiaoyun.li@intel.com>; dev@dpdk.org;
>> linuxarm@openeuler.org
>> Subject: [PATCH] app/testpmd: support Tx mbuf free on demand cmd
>>
>> From: Chengwen Feng <fengchengwen@huawei.com>
>>
>> This patch support tx_done_cleanup command:
>> tx_done_cleanup port (port_id) (queue_id) (free_cnt)
>>
>> User must make sure there are no concurrent access to the same Tx queue (like
>> rte_eth_tx_burst, rte_eth_dev_tx_queue_stop and so on) when this command
> Users ...... this command is executed.
OK, I will fix.
>> executed.
>>
>> Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
>> Signed-off-by: Lijun Ou <oulijun@huawei.com>
>> ---
>>   app/test-pmd/cmdline.c                      | 91 +++++++++++++++++++++++++++++
>>   doc/guides/rel_notes/release_21_05.rst      |  2 +
>>   doc/guides/testpmd_app_ug/testpmd_funcs.rst |  7 +++
>>   3 files changed, 100 insertions(+)
>>
>> diff --git a/app/test-pmd/cmdline.c b/app/test-pmd/cmdline.c index
>> 14110eb..832ae70 100644
>> --- a/app/test-pmd/cmdline.c
>> +++ b/app/test-pmd/cmdline.c
>> @@ -36,6 +36,7 @@
>>   #include <rte_pci.h>
>>   #include <rte_ether.h>
>>   #include <rte_ethdev.h>
>> +#include <rte_ethdev_driver.h>
>>   #include <rte_string_fns.h>
>>   #include <rte_devargs.h>
>>   #include <rte_flow.h>
>> @@ -675,6 +676,9 @@ static void cmd_help_long_parsed(void *parsed_result,
>>   			"set port (port_id) ptype_mask (ptype_mask)\n"
>>   			"    set packet types classification for a specific
>> port\n\n"
>>
>> +			"tx_done_cleanup (port_id) (queue_id) (free_cnt)\n"
>> +			"    Cleanup a tx queue's mbuf on a port\n\n"
>> +
>>   			"set port (port_id) queue-region region_id (value) "
>>   			"queue_start_index (value) queue_num (value)\n"
>>   			"    Set a queue region on a port\n\n"
>> @@ -16910,6 +16914,92 @@ cmdline_parse_inst_t cmd_showport_macs = {
>>   	},
>>   };
>>
>> +/* *** tx_done_cleanup *** */
>> +struct cmd_tx_done_cleanup_result {
>> +	cmdline_fixed_string_t clean;
>> +	cmdline_fixed_string_t port;
>> +	uint16_t port_id;
>> +	uint16_t queue_id;
>> +	uint32_t free_cnt;
>> +};
>> +
>> +static void
>> +cmd_tx_done_cleanup_parsed(void *parsed_result,
>> +			   __rte_unused struct cmdline *cl,
>> +			   __rte_unused void *data)
>> +{
>> +	struct cmd_tx_done_cleanup_result *res = parsed_result;
>> +	struct rte_eth_dev *dev;
>> +	uint16_t port_id = res->port_id;
>> +	uint16_t queue_id = res->queue_id;
>> +	uint32_t free_cnt = res->free_cnt;
>> +	int ret;
>> +
>> +	if (!rte_eth_dev_is_valid_port(port_id)) {
>> +		printf("Invalid port_id %u\n", port_id);
>> +		return;
>> +	}
>> +
>> +	dev = &rte_eth_devices[port_id];
>> +	if (queue_id >= dev->data->nb_tx_queues) {
>> +		printf("Invalid TX queue_id %u\n", queue_id);
> Tx? You just want to send a patch to use Rx/Tx. You should keep concurrency.
Good idea. I will fix it.
>> +		return;
>> +	}
>> +
>> +	if (dev->data->tx_queue_state[queue_id] !=
>> +		RTE_ETH_QUEUE_STATE_STARTED) {
>> +		printf("TX queue_id %u not started!\n", queue_id);
> Tx?
>
>> +		return;
>> +	}
>> +
>> +	/*
>> +	 * rte_eth_tx_done_cleanup is a dataplane API, user must make sure
>> +	 * there are no concurrent access to the same Tx queue (like
>> +	 * rte_eth_tx_burst, rte_eth_dev_tx_queue_stop and so on) when this
>> API
>> +	 * called.
>> +	 */
> And I have some concerns on this. Users cannot know about this unless they read your code. I don't think this will likely happen.
> So you should document this in testpmd doc when you introduced this command.
>
> Or maybe you can have a way to stop that to happen. Maybe checking "test_done && engine != rxonly" before this?
> In your comment, the tx forwarding shouldn't happen, right? Every fwd engine except rxonly will contain tx.
> Well, it's still a rough way because tx may not happen even if it's io fwd.
>
> Maybe other people have better ideas. Otherwise, you should at least document it.
> @Yigit, Ferruh What do you think? Is there a better way?
I have add doc for noting.
>> +	ret = rte_eth_tx_done_cleanup(port_id, queue_id, free_cnt);
>> +	if (ret < 0) {
>> +		printf("Failed to cleanup mbuf for port %u TX queue %u "
> Tx?
>
>> +		       "error desc: %s(%d)\n",
>> +		       port_id, queue_id, strerror(-ret), ret);
>> +		return;
>> +	}
>> +
>> +	printf("Cleanup port %u TX queue %u mbuf nums: %u\n",
> Tx?
>
>> +	       port_id, queue_id, ret);
>> +}
>> +
>> +cmdline_parse_token_string_t cmd_tx_done_cleanup_clean =
>> +	TOKEN_STRING_INITIALIZER(struct cmd_tx_done_cleanup_result, clean,
>> +				 "tx_done_cleanup");
>> +cmdline_parse_token_string_t cmd_tx_done_cleanup_port =
>> +	TOKEN_STRING_INITIALIZER(struct cmd_tx_done_cleanup_result, port,
>> +				 "port");
>> +cmdline_parse_token_num_t cmd_tx_done_cleanup_port_id =
>> +	TOKEN_NUM_INITIALIZER(struct cmd_tx_done_cleanup_result, port_id,
>> +			      UINT16);
>> +cmdline_parse_token_num_t cmd_tx_done_cleanup_queue_id =
>> +	TOKEN_NUM_INITIALIZER(struct cmd_tx_done_cleanup_result,
>> queue_id,
>> +			      UINT16);
>> +cmdline_parse_token_num_t cmd_tx_done_cleanup_free_cnt =
>> +	TOKEN_NUM_INITIALIZER(struct cmd_tx_done_cleanup_result,
>> free_cnt,
>> +			      UINT32);
>> +
>> +cmdline_parse_inst_t cmd_tx_done_cleanup = {
>> +	.f = cmd_tx_done_cleanup_parsed,
>> +	.data = NULL,
>> +	.help_str = "tx_done_cleanup port <port_id> <queue_id> <free_cnt>",
>> +	.tokens = {
>> +		(void *)&cmd_tx_done_cleanup_clean,
>> +		(void *)&cmd_tx_done_cleanup_port,
>> +		(void *)&cmd_tx_done_cleanup_port_id,
>> +		(void *)&cmd_tx_done_cleanup_queue_id,
>> +		(void *)&cmd_tx_done_cleanup_free_cnt,
>> +		NULL,
>> +	},
>> +};
>> +
>>   /*
>> *****************************************************************
>> *************** */
>>
>>   /* list of instructions */
>> @@ -17035,6 +17125,7 @@ cmdline_parse_ctx_t main_ctx[] = {
>>   	(cmdline_parse_inst_t *)&cmd_config_rss_reta,
>>   	(cmdline_parse_inst_t *)&cmd_showport_reta,
>>   	(cmdline_parse_inst_t *)&cmd_showport_macs,
>> +	(cmdline_parse_inst_t *)&cmd_tx_done_cleanup,
>>   	(cmdline_parse_inst_t *)&cmd_config_burst,
>>   	(cmdline_parse_inst_t *)&cmd_config_thresh,
>>   	(cmdline_parse_inst_t *)&cmd_config_threshold, diff --git
>> a/doc/guides/rel_notes/release_21_05.rst
>> b/doc/guides/rel_notes/release_21_05.rst
>> index 23f7f0b..8077573 100644
>> --- a/doc/guides/rel_notes/release_21_05.rst
>> +++ b/doc/guides/rel_notes/release_21_05.rst
>> @@ -69,6 +69,8 @@ New Features
>>
>>     * Added command to display Rx queue used descriptor count.
>>       ``show port (port_id) rxq (queue_id) desc used count``
>> +  * Added command to cleanup a Tx queue's mbuf on a port.
>> +    ``tx_done_cleanup port <port_id> <queue_id> <free_cnt>``
>>
>>
>>   Removed Items
>> diff --git a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
>> b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
>> index f59eb8a..39281f5 100644
>> --- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
>> +++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
>> @@ -272,6 +272,13 @@ and ready to be processed by the driver on a given RX
>> queue::
>>
>>      testpmd> show port (port_id) rxq (queue_id) desc used count
>>
>> +cleanup txq mbufs
>> +~~~~~~~~~~~~~~~~~~~~~~~~
>> +
>> +Request the driver to free mbufs currently cached by the driver for a
>> +given port's Tx queue::
>> +   testpmd> tx_done_cleanup port (port_id) (queue_id) (free_cnt)
>> +
>>   show config
>>   ~~~~~~~~~~~
>>
>> --
>> 2.7.4
> .
>
diff mbox series

Patch

diff --git a/app/test-pmd/cmdline.c b/app/test-pmd/cmdline.c
index 14110eb..832ae70 100644
--- a/app/test-pmd/cmdline.c
+++ b/app/test-pmd/cmdline.c
@@ -36,6 +36,7 @@ 
 #include <rte_pci.h>
 #include <rte_ether.h>
 #include <rte_ethdev.h>
+#include <rte_ethdev_driver.h>
 #include <rte_string_fns.h>
 #include <rte_devargs.h>
 #include <rte_flow.h>
@@ -675,6 +676,9 @@  static void cmd_help_long_parsed(void *parsed_result,
 			"set port (port_id) ptype_mask (ptype_mask)\n"
 			"    set packet types classification for a specific port\n\n"
 
+			"tx_done_cleanup (port_id) (queue_id) (free_cnt)\n"
+			"    Cleanup a tx queue's mbuf on a port\n\n"
+
 			"set port (port_id) queue-region region_id (value) "
 			"queue_start_index (value) queue_num (value)\n"
 			"    Set a queue region on a port\n\n"
@@ -16910,6 +16914,92 @@  cmdline_parse_inst_t cmd_showport_macs = {
 	},
 };
 
+/* *** tx_done_cleanup *** */
+struct cmd_tx_done_cleanup_result {
+	cmdline_fixed_string_t clean;
+	cmdline_fixed_string_t port;
+	uint16_t port_id;
+	uint16_t queue_id;
+	uint32_t free_cnt;
+};
+
+static void
+cmd_tx_done_cleanup_parsed(void *parsed_result,
+			   __rte_unused struct cmdline *cl,
+			   __rte_unused void *data)
+{
+	struct cmd_tx_done_cleanup_result *res = parsed_result;
+	struct rte_eth_dev *dev;
+	uint16_t port_id = res->port_id;
+	uint16_t queue_id = res->queue_id;
+	uint32_t free_cnt = res->free_cnt;
+	int ret;
+
+	if (!rte_eth_dev_is_valid_port(port_id)) {
+		printf("Invalid port_id %u\n", port_id);
+		return;
+	}
+
+	dev = &rte_eth_devices[port_id];
+	if (queue_id >= dev->data->nb_tx_queues) {
+		printf("Invalid TX queue_id %u\n", queue_id);
+		return;
+	}
+
+	if (dev->data->tx_queue_state[queue_id] !=
+		RTE_ETH_QUEUE_STATE_STARTED) {
+		printf("TX queue_id %u not started!\n", queue_id);
+		return;
+	}
+
+	/*
+	 * rte_eth_tx_done_cleanup is a dataplane API, user must make sure
+	 * there are no concurrent access to the same Tx queue (like
+	 * rte_eth_tx_burst, rte_eth_dev_tx_queue_stop and so on) when this API
+	 * called.
+	 */
+	ret = rte_eth_tx_done_cleanup(port_id, queue_id, free_cnt);
+	if (ret < 0) {
+		printf("Failed to cleanup mbuf for port %u TX queue %u "
+		       "error desc: %s(%d)\n",
+		       port_id, queue_id, strerror(-ret), ret);
+		return;
+	}
+
+	printf("Cleanup port %u TX queue %u mbuf nums: %u\n",
+	       port_id, queue_id, ret);
+}
+
+cmdline_parse_token_string_t cmd_tx_done_cleanup_clean =
+	TOKEN_STRING_INITIALIZER(struct cmd_tx_done_cleanup_result, clean,
+				 "tx_done_cleanup");
+cmdline_parse_token_string_t cmd_tx_done_cleanup_port =
+	TOKEN_STRING_INITIALIZER(struct cmd_tx_done_cleanup_result, port,
+				 "port");
+cmdline_parse_token_num_t cmd_tx_done_cleanup_port_id =
+	TOKEN_NUM_INITIALIZER(struct cmd_tx_done_cleanup_result, port_id,
+			      UINT16);
+cmdline_parse_token_num_t cmd_tx_done_cleanup_queue_id =
+	TOKEN_NUM_INITIALIZER(struct cmd_tx_done_cleanup_result, queue_id,
+			      UINT16);
+cmdline_parse_token_num_t cmd_tx_done_cleanup_free_cnt =
+	TOKEN_NUM_INITIALIZER(struct cmd_tx_done_cleanup_result, free_cnt,
+			      UINT32);
+
+cmdline_parse_inst_t cmd_tx_done_cleanup = {
+	.f = cmd_tx_done_cleanup_parsed,
+	.data = NULL,
+	.help_str = "tx_done_cleanup port <port_id> <queue_id> <free_cnt>",
+	.tokens = {
+		(void *)&cmd_tx_done_cleanup_clean,
+		(void *)&cmd_tx_done_cleanup_port,
+		(void *)&cmd_tx_done_cleanup_port_id,
+		(void *)&cmd_tx_done_cleanup_queue_id,
+		(void *)&cmd_tx_done_cleanup_free_cnt,
+		NULL,
+	},
+};
+
 /* ******************************************************************************** */
 
 /* list of instructions */
@@ -17035,6 +17125,7 @@  cmdline_parse_ctx_t main_ctx[] = {
 	(cmdline_parse_inst_t *)&cmd_config_rss_reta,
 	(cmdline_parse_inst_t *)&cmd_showport_reta,
 	(cmdline_parse_inst_t *)&cmd_showport_macs,
+	(cmdline_parse_inst_t *)&cmd_tx_done_cleanup,
 	(cmdline_parse_inst_t *)&cmd_config_burst,
 	(cmdline_parse_inst_t *)&cmd_config_thresh,
 	(cmdline_parse_inst_t *)&cmd_config_threshold,
diff --git a/doc/guides/rel_notes/release_21_05.rst b/doc/guides/rel_notes/release_21_05.rst
index 23f7f0b..8077573 100644
--- a/doc/guides/rel_notes/release_21_05.rst
+++ b/doc/guides/rel_notes/release_21_05.rst
@@ -69,6 +69,8 @@  New Features
 
   * Added command to display Rx queue used descriptor count.
     ``show port (port_id) rxq (queue_id) desc used count``
+  * Added command to cleanup a Tx queue's mbuf on a port.
+    ``tx_done_cleanup port <port_id> <queue_id> <free_cnt>``
 
 
 Removed Items
diff --git a/doc/guides/testpmd_app_ug/testpmd_funcs.rst b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
index f59eb8a..39281f5 100644
--- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
+++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
@@ -272,6 +272,13 @@  and ready to be processed by the driver on a given RX queue::
 
    testpmd> show port (port_id) rxq (queue_id) desc used count
 
+cleanup txq mbufs
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+Request the driver to free mbufs currently cached by the driver for a given port's
+Tx queue::
+   testpmd> tx_done_cleanup port (port_id) (queue_id) (free_cnt)
+
 show config
 ~~~~~~~~~~~