| Message ID | 20220310084005.262551-1-horatiu.vultur@microchip.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | fb9eb027fbc90e21cbda18379d85f8603e1f28b9 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net-next,v2] net: lan966x: Improve the CPU TX bitrate. | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Clearly marked for net-next |
| netdev/fixes_present | success | Fixes tag not required for -next series |
| netdev/subject_prefix | success | Link |
| netdev/cover_letter | success | Single patches do not need cover letters |
| netdev/patch_count | success | Link |
| netdev/header_inline | success | No static functions without inline keyword in header files |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/cc_maintainers | success | CCed 5 of 5 maintainers |
| netdev/build_clang | success | Errors and warnings before: 0 this patch: 0 |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Signed-off-by tag matches author and committer |
| netdev/verify_fixes | success | No Fixes tag |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/checkpatch | warning | WARNING: line length of 82 exceeds 80 columns |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/source_inline | success | Was 0 now: 0 |
On Thu, Mar 10, 2022 at 09:40:05AM +0100, Horatiu Vultur wrote: > When doing manual injection of the frame, it is required to check if the > TX FIFO is ready to accept the next word of the frame. For this we are > using 'readx_poll_timeout_atomic', the only problem is that before it > actually checks the status, is determining the time when to finish polling > the status. Which seems to be an expensive operation. > Therefore check the status of the TX FIFO before calling > 'readx_poll_timeout_atomic'. > Doing this will improve the TX bitrate by ~70%. Because 99% the FIFO is > ready by that time. The measurements were done using iperf3. > > Before: > [ ID] Interval Transfer Bitrate Retr > [ 5] 0.00-10.03 sec 55.2 MBytes 46.2 Mbits/sec 0 sender > [ 5] 0.00-10.04 sec 53.8 MBytes 45.0 Mbits/sec receiver > > After: > [ ID] Interval Transfer Bitrate Retr > [ 5] 0.00-10.10 sec 95.0 MBytes 78.9 Mbits/sec 0 sender > [ 5] 0.00-10.11 sec 95.0 MBytes 78.8 Mbits/sec receiver > > Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Andrew
Hello: This patch was applied to netdev/net-next.git (master) by David S. Miller <davem@davemloft.net>: On Thu, 10 Mar 2022 09:40:05 +0100 you wrote: > When doing manual injection of the frame, it is required to check if the > TX FIFO is ready to accept the next word of the frame. For this we are > using 'readx_poll_timeout_atomic', the only problem is that before it > actually checks the status, is determining the time when to finish polling > the status. Which seems to be an expensive operation. > Therefore check the status of the TX FIFO before calling > 'readx_poll_timeout_atomic'. > Doing this will improve the TX bitrate by ~70%. Because 99% the FIFO is > ready by that time. The measurements were done using iperf3. > > [...] Here is the summary with links: - [net-next,v2] net: lan966x: Improve the CPU TX bitrate. https://git.kernel.org/netdev/net-next/c/fb9eb027fbc9 You are awesome, thank you!
diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c index 81c01665d01e..e1bcb28039dc 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c @@ -185,6 +185,9 @@ static int lan966x_port_inj_ready(struct lan966x *lan966x, u8 grp) { u32 val; + if (lan_rd(lan966x, QS_INJ_STATUS) & QS_INJ_STATUS_FIFO_RDY_SET(BIT(grp))) + return 0; + return readx_poll_timeout_atomic(lan966x_port_inj_status, lan966x, val, QS_INJ_STATUS_FIFO_RDY_GET(val) & BIT(grp), READL_SLEEP_US, READL_TIMEOUT_US);
When doing manual injection of the frame, it is required to check if the TX FIFO is ready to accept the next word of the frame. For this we are using 'readx_poll_timeout_atomic', the only problem is that before it actually checks the status, is determining the time when to finish polling the status. Which seems to be an expensive operation. Therefore check the status of the TX FIFO before calling 'readx_poll_timeout_atomic'. Doing this will improve the TX bitrate by ~70%. Because 99% the FIFO is ready by that time. The measurements were done using iperf3. Before: [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-10.03 sec 55.2 MBytes 46.2 Mbits/sec 0 sender [ 5] 0.00-10.04 sec 53.8 MBytes 45.0 Mbits/sec receiver After: [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-10.10 sec 95.0 MBytes 78.9 Mbits/sec 0 sender [ 5] 0.00-10.11 sec 95.0 MBytes 78.8 Mbits/sec receiver Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> --- v1->v2 - check for TX FIFO status before calling readx_poll_timeout_atomic --- drivers/net/ethernet/microchip/lan966x/lan966x_main.c | 3 +++ 1 file changed, 3 insertions(+)