The branch main has been updated by kbowling:
URL:
https://cgit.FreeBSD.org/src/commit/?id=9bf9164fc8aad1ca828c725413e06462aef1e4dd
commit 9bf9164fc8aad1ca828c725413e06462aef1e4dd
Author: Kevin Bowling <kbowl...@freebsd.org>
AuthorDate: 2024-09-27 08:03:31 +0000
Commit: Kevin Bowling <kbowl...@freebsd.org>
CommitDate: 2024-09-27 08:30:05 +0000
e1000: Clean up ITR/EITR in preparation for AIM
Provide macros to derive the various needed values and make it a bit
more clear the differences between em and igb.
The igb default EITR was not landing at the right offset.
Respect the 'max_interrupt_rate' tunable.
MFC after: 1 week
Sponsored by: BBOX.io
---
sys/dev/e1000/if_em.c | 20 ++++++++------------
sys/dev/e1000/if_em.h | 11 +++++++++--
2 files changed, 17 insertions(+), 14 deletions(-)
diff --git a/sys/dev/e1000/if_em.c b/sys/dev/e1000/if_em.c
index cdadec17e355..b9c6131e6741 100644
--- a/sys/dev/e1000/if_em.c
+++ b/sys/dev/e1000/if_em.c
@@ -499,9 +499,6 @@ static driver_t igb_if_driver = {
#define EM_TICKS_TO_USECS(ticks) ((1024 * (ticks) + 500) / 1000)
#define EM_USECS_TO_TICKS(usecs) ((1000 * (usecs) + 512) / 1024)
-#define MAX_INTS_PER_SEC 8000
-#define DEFAULT_ITR (1000000000/(MAX_INTS_PER_SEC * 256))
-
/* Allow common code without TSO */
#ifndef CSUM_TSO
#define CSUM_TSO 0
@@ -551,7 +548,7 @@ SYSCTL_INT(_hw_em, OID_AUTO, eee_setting, CTLFLAG_RDTUN,
&eee_setting, 0,
/*
** Tuneable Interrupt rate
*/
-static int em_max_interrupt_rate = 8000;
+static int em_max_interrupt_rate = EM_INTS_PER_SEC;
SYSCTL_INT(_hw_em, OID_AUTO, max_interrupt_rate, CTLFLAG_RDTUN,
&em_max_interrupt_rate, 0, "Maximum interrupts per second");
@@ -1050,7 +1047,8 @@ em_if_attach_pre(if_ctx_t ctx)
E1000_REGISTER(hw, E1000_TADV), em_tx_abs_int_delay_dflt);
em_add_int_delay_sysctl(sc, "itr",
"interrupt delay limit in usecs/4", &sc->tx_itr,
- E1000_REGISTER(hw, E1000_ITR), DEFAULT_ITR);
+ E1000_REGISTER(hw, E1000_ITR),
+ EM_INTS_TO_ITR(em_max_interrupt_rate));
}
hw->mac.autoneg = DO_AUTO_NEG;
@@ -2287,7 +2285,7 @@ igb_configure_queues(struct e1000_softc *sc)
/* Set the igb starting interrupt rate */
if (em_max_interrupt_rate > 0) {
- newitr = (4000000 / em_max_interrupt_rate) & 0x7FFC;
+ newitr = IGB_INTS_TO_EITR(em_max_interrupt_rate);
if (hw->mac.type == e1000_82575)
newitr |= newitr << 16;
@@ -3386,11 +3384,9 @@ em_initialize_receive_unit(if_ctx_t ctx)
if (hw->mac.type >= e1000_82540) {
E1000_WRITE_REG(hw, E1000_RADV,
sc->rx_abs_int_delay.value);
- /*
- * Set the interrupt throttling rate. Value is
calculated
- * as DEFAULT_ITR = 1/(MAX_INTS_PER_SEC * 256ns)
- */
- E1000_WRITE_REG(hw, E1000_ITR, DEFAULT_ITR);
+ /* Set the default interrupt throttling rate */
+ E1000_WRITE_REG(hw, E1000_ITR,
+ EM_INTS_TO_ITR(em_max_interrupt_rate));
}
/* XXX TEMPORARY WORKAROUND: on some systems with 82573
@@ -3418,7 +3414,7 @@ em_initialize_receive_unit(if_ctx_t ctx)
if (hw->mac.type == e1000_82574) {
for (int i = 0; i < 4; i++)
E1000_WRITE_REG(hw, E1000_EITR_82574(i),
- DEFAULT_ITR);
+ EM_INTS_TO_ITR(em_max_interrupt_rate));
/* Disable accelerated acknowledge */
rfctl |= E1000_RFCTL_ACK_DIS;
}
diff --git a/sys/dev/e1000/if_em.h b/sys/dev/e1000/if_em.h
index 244762e8ed0d..7219dc57c333 100644
--- a/sys/dev/e1000/if_em.h
+++ b/sys/dev/e1000/if_em.h
@@ -244,8 +244,15 @@
#define IGB_MEDIA_RESET (1 << 0)
/* Define the starting Interrupt rate per Queue */
-#define IGB_INTS_PER_SEC 8000
-#define IGB_DEFAULT_ITR ((1000000/IGB_INTS_PER_SEC) << 2)
+#define EM_INTS_PER_SEC 8000
+#define EM_INTS_MULTIPLIER 256
+#define EM_ITR_DIVIDEND 1000000000
+#define EM_INTS_TO_ITR(i) (EM_ITR_DIVIDEND/(i * EM_INTS_MULTIPLIER))
+#define IGB_ITR_DIVIDEND 1000000
+#define IGB_ITR_SHIFT 2
+#define IGB_QVECTOR_MASK 0x7FFC
+#define IGB_INTS_TO_EITR(i) (((IGB_ITR_DIVIDEND/i) & IGB_QVECTOR_MASK) << \
+ IGB_ITR_SHIFT)
#define IGB_LINK_ITR 2000
#define I210_LINK_DELAY 1000
