62 lines
2.2 KiB
Plaintext
62 lines
2.2 KiB
Plaintext
|
From: jbeulich@novell.com
|
||
|
|
Subject: netback: reduce overhead of IRQ recording
|
||
|
|
Patch-mainline: obsolete
|
||
|
|
|
||
|
|
Since both NR_PIRQS and NR_DYNIRQS are no longer hardcoded, the
|
||
|
|
(memory) overhead of tracking which ones to send notifications to can
|
||
|
|
be pretty unbounded. Also, store the dynirq rather than the raw irq
|
||
|
|
to push up the limit where the type of notify_list needs to become
|
||
|
|
'int' rather than 'u16'.
|
||
|
|
|
||
|
|
--- head-2010-01-19.orig/drivers/xen/netback/interface.c 2010-01-26 08:58:19.000000000 +0100
|
||
|
|
+++ head-2010-01-19/drivers/xen/netback/interface.c 2010-01-26 09:03:24.000000000 +0100
|
||
|
|
@@ -343,6 +343,7 @@ int netif_map(netif_t *netif, unsigned l
|
||
|
|
netif->dev->name, netif);
|
||
|
|
if (err < 0)
|
||
|
|
goto err_hypervisor;
|
||
|
|
+ BUG_ON(err < DYNIRQ_BASE || err >= DYNIRQ_BASE + NR_DYNIRQS);
|
||
|
|
netif->irq = err;
|
||
|
|
disable_irq(netif->irq);
|
||
|
|
|
||
|
|
--- head-2010-01-19.orig/drivers/xen/netback/netback.c 2010-01-04 13:31:38.000000000 +0100
|
||
|
|
+++ head-2010-01-19/drivers/xen/netback/netback.c 2010-01-04 13:31:44.000000000 +0100
|
||
|
|
@@ -590,8 +590,12 @@ static void net_rx_action(unsigned long
|
||
|
|
static mmu_update_t rx_mmu[NET_RX_RING_SIZE];
|
||
|
|
static gnttab_transfer_t grant_trans_op[NET_RX_RING_SIZE];
|
||
|
|
static gnttab_copy_t grant_copy_op[NET_RX_RING_SIZE];
|
||
|
|
- static unsigned char rx_notify[NR_IRQS];
|
||
|
|
+ static DECLARE_BITMAP(rx_notify, NR_DYNIRQS);
|
||
|
|
+#if NR_DYNIRQS <= 0x10000
|
||
|
|
static u16 notify_list[NET_RX_RING_SIZE];
|
||
|
|
+#else
|
||
|
|
+ static int notify_list[NET_RX_RING_SIZE];
|
||
|
|
+#endif
|
||
|
|
static struct netbk_rx_meta meta[NET_RX_RING_SIZE];
|
||
|
|
|
||
|
|
struct netrx_pending_operations npo = {
|
||
|
|
@@ -749,11 +753,9 @@ static void net_rx_action(unsigned long
|
||
|
|
nr_frags);
|
||
|
|
|
||
|
|
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&netif->rx, ret);
|
||
|
|
- irq = netif->irq;
|
||
|
|
- if (ret && !rx_notify[irq]) {
|
||
|
|
- rx_notify[irq] = 1;
|
||
|
|
+ irq = netif->irq - DYNIRQ_BASE;
|
||
|
|
+ if (ret && !__test_and_set_bit(irq, rx_notify))
|
||
|
|
notify_list[notify_nr++] = irq;
|
||
|
|
- }
|
||
|
|
|
||
|
|
if (netif_queue_stopped(netif->dev) &&
|
||
|
|
netif_schedulable(netif) &&
|
||
|
|
@@ -778,8 +780,8 @@ static void net_rx_action(unsigned long
|
||
|
|
|
||
|
|
while (notify_nr != 0) {
|
||
|
|
irq = notify_list[--notify_nr];
|
||
|
|
- rx_notify[irq] = 0;
|
||
|
|
- notify_remote_via_irq(irq);
|
||
|
|
+ __clear_bit(irq, rx_notify);
|
||
|
|
+ notify_remote_via_irq(irq + DYNIRQ_BASE);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* More work to do? */
|