Re: [dpdk-dev] [PATCH v15 00/13] Port Hotplug Framework

[Thomas Monjalon <thomas.monjalon@6wind.com>]

2015-02-26 04:32, Tetsuya Mukawa:
> This patch series adds a dynamic port hotplug framework to DPDK.
> With the patches, DPDK apps can attach or detach ports at runtime.
> 
> The basic concept of the port hotplug is like followings.
> - DPDK apps must have responsibility to manage ports.
>   DPDK apps only know which ports are attached or detached at the moment.
>   The port hotplug framework is implemented to allow DPDK apps to manage ports.
>   For example, when DPDK apps call port attach function, attached port number
>   will be returned. Also, DPDK apps can detach port by port number.
> - Kernel support is needed for attaching or detaching physical device ports.
>   To attach a new physical device port, the device will be recognized by
>   userspace directly I/O framework in kernel at first. Then DPDK apps can
>   call the port hotplug functions to attach ports.
>   For detaching, steps are vice versa.
> - Before detach ports, ports must be stopped and closed.
>   DPDK application must call rte_eth_dev_stop() and rte_eth_dev_close() before
>   detaching ports. These function will call finalization codes of PMDs.
>   But so far, no PMD frees all resources allocated by initialization.
>   It means PMDs are needed to be fixed to support the port hotplug.
>   'RTE_PCI_DRV_DETACHABLE' is a new flag indicating a PMD supports detaching.
>   Without this flag, detaching will be failed.
> - Mustn't affect legacy DPDK apps.
>   No DPDK EAL behavior is changed, if the port hotplug functions are't called.
>   So all legacy DPDK apps can still work without modifications.
> 
> And a few limitations.
> - The port hotplug functions are not thread safe.
>   DPDK apps should handle it.
> - Only support Linux and igb_uio so far.
>   BSD and VFIO is not supported. I will send VFIO patches at least, but I don't
>   have a plan to submit BSD patch so far.
> 
> 
> Here is port hotplug APIs.
> -------------------------------------------------------------------------------
> /**
>  * Attach a new device.
>  *
>  * @param devargs
>  *   A pointer to a strings array describing the new device
>  *   to be attached. The strings should be a pci address like
>  *   '0000:01:00.0' or virtual device name like 'eth_pcap0'.
>  * @param port_id
>  *  A pointer to a port identifier actually attached.
>  * @return
>  *  0 on success and port_id is filled, negative on error
>  */
> int rte_eth_dev_attach(const char *devargs, uint8_t *port_id);
> 
> /**
>  * Detach a device.
>  *
>  * @param port_id
>  *   The port identifier of the device to detach.
>  * @param addr
>  *  A pointer to a device name actually detached.
>  * @return
>  *  0 on success and devname is filled, negative on error
>  */
> int rte_eth_dev_detach(uint8_t port_id, char *devname);
> -------------------------------------------------------------------------------
> 
> This patch series are for DPDK EAL. To use port hotplug function by DPDK apps,
> each PMD should be fixed to support 'RTE_PCI_DRV_DETACHABLE' flag. Please check
> a patch for pcap PMD.
> 
> Also, please check testpmd patch. It will show you how to fix your legacy
> applications to support port hotplug feature.
> 
> PATCH v15 changes
>  - Fix issue that eal calls ethedv library APIs.
>   - Remove rte_eal_dev_attach(), and add rte_eth_dev_attach().
>   - Remove rte_eal_dev_detach(), and add rte_eth_dev_detach().
>   - Call rte_eal_vdev_init/uninit from ethdev library.
>    (Thanks to Thomas Monjalon)
>  - Fix version.map
>  - Reorder and squash patches to compile correctly.
>  - Remove needless symbols in version.map
>  - Fix version.map.
> 
> PATCH v14 changes
>  - Remove needless if statement.
>    (Thanks to Maxime Leroy)
> 
> PATCH v13 changes
>  - Change log level when error occurs in rte_eal_vdev_init() and
>    rte_eal_dev_init().
>  - Return value of driver init and uninit functions.
>  - Replace rte_panic by RTE_LOG in rte_eal_dev_init()
>  - Fix return value of rte_eal_vdev_uninit().
>  - Fix rte_eal_dev_attach_vdev to set port_id correctly.
>    (Thanks to Maxime Leroy)
> 
> PATCH v12 changes
>  - Add missing symbol in version map.
>    (Thanks to Iremonger, Bernard)
> 
> PATCH v11 changes
>  - Remove needless devargs handling codes.
>  - Replace get_vdev_name() by rte_eal_parse_devargs_str().
>  - Replace rte_eal_vdev_find_and_init by rte_eal_vdev_init()
>  - Replace rte_eal_vdev_find_and_uninit by rte_eal_vdev_uninit()
>  - Fix rte_eal_dev_init() to use rte_eal_vdev_init().
>  - Remove needless patch.
>    (Thanks to Maxime Leroy)
> 
> PATCH v10 changes
>  - Add comments.
>  - Chagne order of version.map.
>  - Fix comment of "rte_ethdev.h".
>    (Thanks to Thomas Monjalon)
>  - Add size parameter to rte_eth_dev_create_unique_device_name().
>    (Thanks to Iremonger, Bernard)
> 
> PATCH v9 changes
>  - Fix commit title.
>  - Fix commit log.
>  - Fix comments.
>  - Define CONFIG_RTE_LIBRTE_EAL_HOTPLUG at the top of this patch series.
>  - DEV_INVALID/VALID are removed.
>  - DEV_DISCONNECTED is replaced by DEV_DETACHED.
>  - DEV_CONNECTED is replaced by DEV_ATTACHED.
>  - rte_eth_dev_allocate_new_port() is renamed to
>    rte_eth_dev_find_free_port().
>  - rte_eth_dev_validate_port() is renamed to rte_eth_dev_is_valid_port().
>  - rte_eth_dev_is_valid_port() is changed not to handle log toggle.
>  - eal_compare_pci_addr() is replaced by rte_eal_compare_pci_addr().
>  - rte_eth_dev_free() is replaced by rte_eth_dev_release_port().
>  - Add a function to create a unique device name.
>  - Change parameter of pci_devuninit_t and rte_eth_dev_uninit.
>  - Remove code that initiaize callback of ethdev from
>    rte_eth_dev_uninit().
>  - Remove pci_unmap_device(). It will be implemented in later patch.
>  - rte_eth_dev_check_detachable() is replaced by
>    rte_eth_dev_is_detachable().
>  - strncpy() is replaced by strcpy().
>  - Implement pci_unmap_device() in this patch.
>  - Remove "rte_dev_hotplug.h".
>  - Remove needless "#ifdef".
>  - Remove RTE_EAL_INVOKE_TYPE_PROBE/CLOSE.
>  - RTE_ETH_DEV_PHYSICAL is replaced by RTE_ETH_DEV_PCI.
>  - Use strcmp() instead of strncmp().
>  - Remove RTE_EAL_INVOKE_TYPE_PROBE/CLOSE.
>    (Thanks to Thomas Monjalon)
>  - Change definition of rte_dev_uninit_t.
>    (Thanks to Thomas Monjalon and Maxime Leroy)
>  - Add missing symbol in version map.
>    (Thanks to Nail Horman)
> 
> PATCH v8 changes
>  - Fix Makefile and add version map file.
>  - Add missing symbol in version map.
>  - Fix pci_scan_one() to update sysfs values.
>    (Thanks to Qiu, Michael and Iremonger, Bernard)
>  - NONE_TRACE is replaced by NO_TRACE.
>  - Fix typo.
>  - Add size parameter to rte_eth_dev_save().
>    (Thanks to Iremonger, Bernard)
> 
> PATCH v7 changes
>  - Add a new section to programmer's guide.
>    (Thanks to Iremonger, Bernard)
>  - Fix port checking implementation of star_port().
>  - Fix typo of warning messages.
>  - Add pt_driver checking to rte_eth_dev_check_detachable().
>    (Thanks to Qiu, Michael)
> 
> PATCH v6 changes
>  - Fix rte_eth_dev_uninit() to handle a return value of uninit
>    function of PMD. To do this, below changes also be applied.
>    - Fix a parameter of rte_eth_dev_free().
>    - Use rte_eth_dev structure as the paramter of rte_eth_dev_free().
> 
> PATCH v5 changes
>  - Add runtime check passthrough driver type, like vfio-pci, igb_uio
>    and uio_pci_generic.
>    This was done by Qiu, Michael. Thanks a lot.
>  - Change function names like below.
>    - rte_eal_dev_find_and_invoke() to rte_eal_vdev_find_and_invoke().
>    - rte_eal_dev_invoke() to rte_eal_vdev_invoke().
>  - Add code to handle a return value of rte_eal_devargs_remove().
>  - Fix pci address format in rte_eal_dev_detach().
>  - Remove RTE_EAL_INVOKE_TYPE_UNKNOWN, because it's unused.
>  - Change function definition of rte_eal_devargs_remove().
>  - Fix pci_unmap_device() to check pt_driver.
>  - Fix return value of below functions.
>    - rte_eth_dev_get_changed_port().
>    - rte_eth_dev_get_port_by_addr().
>  - Change paramters of rte_eth_dev_validate_port() to cleanup code.
>  - Fix pci_scan_one to handle pt_driver correctly.
>    (Thanks to Qiu, Michael for above suggestions)
> 
> PATCH v4 changes
>  - Merge patches to review easier.
>  - Fix indent of 'if' statement.
>  - Fix calculation method of eal_compare_pci_addr().
>  - Fix header file declaration.
>  - Add header file to determine if hotplug can be enabled.
>    (Thanks to Qiu, Michael)
>  - Use braces with 'for' loop.
>  - Add parameter checking.
>  - Fix sanity check code
>  - Fix comments of rte_eth_dev_type.
>  - Change function names.
>    (Thanks to Iremonger, Bernard)
> 
> PATCH v3 changes:
>  - Fix enum definition used in rte_ethdev.c.
>    (Thanks to Zhang, Helin)
> 
> PATCH v2 changes:
>  - Replace rte_eal_dev_attach_pdev(), rte_eal_dev_detach_pdev,
>    rte_eal_dev_attach_vdev() and rte_eal_dev_detach_vdev() to
>    rte_eal_dev_attach() and rte_eal_dev_detach().
>  - Add parameter values checking.
>  - Refashion a few functions.
>    (Thanks to Iremonger, Bernard)
> 
> PATCH v1 Changes:
>  - Fix error checking code of librte_eth APIs.
>  - Fix issue that port from pcap PMD cannot be detached correctly.
>  - Fix issue that testpmd could hang after forwarding, if attaching and detaching
>    is repeatedly.
>  - Fix if-condition of rte_eth_dev_get_port_by_addr().
>    (Thanks to Mark Enright)
> 
> RFC PATCH v2 Changes:
> - remove 'rte_eth_dev_validate_port()', and cleanup codes.
> 
> 
> Michael Qiu (2):
>   eal_pci: Add flag to hold kernel driver type
>   eal_pci: pci memory map work with driver type
> 
> Tetsuya Mukawa (11):
>   eal: Enable port Hotplug framework in Linux
>   eal/pci,ethdev: Remove assumption that port will not be detached
>   eal/pci: Consolidate pci address comparison APIs
>   ethdev: Add rte_eth_dev_release_port to release specified port
>   eal,ethdev: Add a function and function pointers to close ether device
>   eal/linux/pci: Add functions for unmapping igb_uio resources
>   eal/pci: Add probe and close functions of pci driver
>   ethdev: Add one dev_type parameter to rte_eth_dev_allocate
>   eal/pci: Add vdev driver initialization and uninitialization functions
>   ethdev: Add rte_eth_dev_attach/detach() functions
>   doc: Add port hotplug framework section to programmers guide

Applied, thanks Tetsuya for this long work