ionic: minimize resources when under kdump

When running in a small kdump kernel, we can play nice and
minimize our resource use to help make sure that kdump is
successful in its mission.

Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_lif.c b/drivers/net/ethernet/pensando/ionic/ionic_lif.c
index 537c290..453994e 100644 (file)
--- a/drivers/net/ethernet/pensando/ionic/ionic_lif.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_lif.c
@@ -11,6 +11,7 @@
 #include <linux/interrupt.h>
 #include <linux/pci.h>
 #include <linux/cpumask.h>
+#include <linux/crash_dump.h>
 
 #include "ionic.h"
 #include "ionic_bus.h"
@@ -2834,8 +2835,14 @@ int ionic_lif_alloc(struct ionic *ionic)
 
        lif->ionic = ionic;
        lif->index = 0;
-       lif->ntxq_descs = IONIC_DEF_TXRX_DESC;
-       lif->nrxq_descs = IONIC_DEF_TXRX_DESC;
+
+       if (is_kdump_kernel()) {
+               lif->ntxq_descs = IONIC_MIN_TXRX_DESC;
+               lif->nrxq_descs = IONIC_MIN_TXRX_DESC;
+       } else {
+               lif->ntxq_descs = IONIC_DEF_TXRX_DESC;
+               lif->nrxq_descs = IONIC_DEF_TXRX_DESC;
+       }
 
        /* Convert the default coalesce value to actual hw resolution */
        lif->rx_coalesce_usecs = IONIC_ITR_COAL_USEC_DEFAULT;
@@ -3519,6 +3526,7 @@ int ionic_lif_size(struct ionic *ionic)
        unsigned int min_intrs;
        int err;
 
+       /* retrieve basic values from FW */
        lc = &ident->lif.eth.config;
        dev_nintrs = le32_to_cpu(ident->dev.nintrs);
        neqs_per_lif = le32_to_cpu(ident->lif.rdma.eq_qtype.qid_count);
@@ -3526,6 +3534,15 @@ int ionic_lif_size(struct ionic *ionic)
        ntxqs_per_lif = le32_to_cpu(lc->queue_count[IONIC_QTYPE_TXQ]);
        nrxqs_per_lif = le32_to_cpu(lc->queue_count[IONIC_QTYPE_RXQ]);
 
+       /* limit values to play nice with kdump */
+       if (is_kdump_kernel()) {
+               dev_nintrs = 2;
+               neqs_per_lif = 0;
+               nnqs_per_lif = 0;
+               ntxqs_per_lif = 1;
+               nrxqs_per_lif = 1;
+       }
+
        /* reserve last queue id for hardware timestamping */
        if (lc->features & cpu_to_le64(IONIC_ETH_HW_TIMESTAMP)) {
                if (ntxqs_per_lif <= 1 || nrxqs_per_lif <= 1) {