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[pxe] Update UNDI transmit count before transmitting packet 

It is possible that the UNDI ISR may be triggered before netdev_tx()
returns control to pxenv_undi_transmit().  This means that
pxenv_undi_isr() may see a zero undi_tx_count, and so not check for TX
completions.  This is not a significant problem, since it will check
for TX completions on the next call to pxenv_undi_isr() anyway; it
just means that the NBP will see a spurious IRQ that was apparently
caused by nothing.

Fix by updating the undi_tx_count before calling netdev_tx(), so that
pxenv_undi_isr() can decrement it and report the TX completion.
This commit is contained in:
Michael Brown 2009-06-27 16:36:21 +01:00
parent f186ada2d3
commit c26a38b313
1 changed files with 8 additions and 4 deletions
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12
src/arch/i386/interface/pxe/pxe_undi.c
View File

@ -316,18 +316,22 @@ PXENV_EXIT_t pxenv_undi_transmit ( struct s_PXENV_UNDI_TRANSMIT
}
}
/* Flag transmission as in-progress. Do this before starting
* to transmit the packet, because the ISR may trigger before
* we return from netdev_tx().
*/
undi_tx_count++;
/* Transmit packet */
DBG2 ( "\n" ); /* ISR may trigger before we return from netdev_tx() */
DBG2 ( "\n" );
if ( ( rc = netdev_tx ( pxe_netdev, iobuf ) ) != 0 ) {
DBG2 ( "PXENV_UNDI_TRANSMIT could not transmit: %s\n",
strerror ( rc ) );
undi_tx_count--;
undi_transmit->Status = PXENV_STATUS ( rc );
return PXENV_EXIT_FAILURE;
}
/* Flag transmission as in-progress */
undi_tx_count++;
undi_transmit->Status = PXENV_STATUS_SUCCESS;
return PXENV_EXIT_SUCCESS;
}