Date: Mon, 02 Aug 2021 01:58:52 UTC
I have a dual port igb card: igb0: <Intel(R) PRO/1000 82576> port 0x2020-0x203f mem 0xd1020000-0xd103ffff,0xd0c00000-0xd0ffffff,0xd1044000-0xd1047fff irq 17 at device 0.0 on pci3 igb0: Using 1024 TX descriptors and 1024 RX descriptors igb0: Using 4 RX queues 4 TX queues igb0: Using MSI-X interrupts with 5 vectors igb0: Ethernet address: xxxx igb0: netmap queues/slots: TX 4/1024, RX 4/1024 igb1: <Intel(R) PRO/1000 82576> port 0x2000-0x201f mem 0xd1000000-0xd101ffff,0xd0800000-0xd0bfffff,0xd1040000-0xd1043fff irq 18 at device 0.1 on pci3 igb1: Using 1024 TX descriptors and 1024 RX descriptors igb1: Using 4 RX queues 4 TX queues igb1: Using MSI-X interrupts with 5 vectors igb1: Ethernet address: xxxx igb1: netmap queues/slots: TX 4/1024, RX 4/1024 And I have observed an issue with it when adjusting flow control, it seems to adjust both ports at the same time: # sysctl dev.igb.0.fc dev.igb.0.fc: 3 # sysctl dev.igb.1.fc dev.igb.1.fc: 3 # sysctl dev.igb.0.fc=0 dev.igb.0.fc: 3 -> 0 # sysctl dev.igb.1.fc dev.igb.1.fc: 0 Is this correct behavior? Also, the fc sysctl is not documented, I propose the following: diff --git a/share/man/man4/em.4 b/share/man/man4/em.4 index a1fa22c..bad82e9 100644 --- a/share/man/man4/em.4 +++ b/share/man/man4/em.4 @@ -265,6 +265,26 @@ If is non-zero, this tunable limits the maximum delay in which a transmit interrupt is generated. .El +.Sh SYSCTL VARIABLES +The following variable is availabel: +.Bl -tag -width "dev.em.X.fc" +.It Va dev.em.X.fc +This sysctl sets the flow control for the card (this means both ports +on a dual port card). The values are as follows: +.Bl -tag -width "XX" -offset "XXXX" -compact +.It 0 +Disabled +.It 1 +Process received pause frames, do not transmit them. +.It 2 +Send pause frames, but to not process received frames. +.It 3 +Process and send pause frames. +.It 4 +No software override, use EEPROM configuration. +.El +.El +Note: That the variable is available for igb as well. .Sh FILES .Bl -tag -width /dev/led/em* .It Pa /dev/led/em* -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."