From: Lewis Donzis <lew@perftech.com>
To: dev <dev@dpdk.org>
Subject: ixgbe link status semi-broken on FreeBSD
Date: Wed, 14 Feb 2024 18:38:54 -0600 (CST) [thread overview]
Message-ID: <1480279383.14236704.1707957534180.JavaMail.zimbra@donzis.com> (raw)
I keep meaning to mention this because we've been patching the ixgbe driver for a while...
In ixgbe_ethdev.c, function ixgbe_dev_link_update_share(), we find the following:
/* BSD has no interrupt mechanism, so force NIC status synchronization. */
#ifdef RTE_EXEC_ENV_FREEBSD
wait = 1;
#endif
Which changes the behavior of rte_eth_link_get_nowait() and causes it to wait. For a port that does not have link up, this takes approximately 12-14 seconds before it returns, which is highly undesirable.
However, after disabling this one line of code, it still appears to work properly. It returns the correct link status on ports that are up or down, but does so without any delay.
So I'm wondering, is this still necessary? No doubt, FreeBSD doesn't support interrupts, but why does that require that we wait in this case? Empirically, it works much better without that line of code.
reply other threads:[~2024-02-15 0:38 UTC|newest]
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