be034fc140
The CPDMA uses one pool of descriptors for both RX and TX which by default split between all channels proportionally depending on total number of CPDMA channels and number of TX and RX channels. As result, more descriptors will be consumed by TX path if there are more TX channels and there is no way now to dedicate more descriptors for RX path. So, add the ability to re-split CPDMA pool of descriptors between RX and TX path via ethtool '-G' command wich will allow to configure and fix number of descriptors used by RX and TX path, which, then, will be split between RX/TX channels proportionally depending on RX/TX channels number and weight. ethtool '-G' command will accept only number of RX entries and rest of descriptors will be arranged for TX automatically. Command: ethtool -G <devname> rx <number of descriptors> defaults and limitations: - minimum number of rx descriptors is 10% of total number of descriptors in CPDMA pool - maximum number of rx descriptors is 90% of total number of descriptors in CPDMA pool - by default, descriptors will be split equally between RX/TX path - any values passed in "tx" parameter will be ignored Usage: # ethtool -g eth0 Pre-set maximums: RX: 7372 RX Mini: 0 RX Jumbo: 0 TX: 0 Current hardware settings: RX: 4096 RX Mini: 0 RX Jumbo: 0 TX: 4096 # ethtool -G eth0 rx 7372 # ethtool -g eth0 Ring parameters for eth0: Pre-set maximums: RX: 7372 RX Mini: 0 RX Jumbo: 0 TX: 0 Current hardware settings: RX: 7372 RX Mini: 0 RX Jumbo: 0 TX: 820 Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.