This change makes the fcoe Rx threads have the same nice value
as lpfc and qla2xxx Rx threads.
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
In fcoe_check_wait_queue() the queue length could temporarily drop to 0,
before the last frame was successfully sent. This resulted in out of order
data frames within a single sequence, leading to IO timeout errors.
This builds on the approach from Vasu Dev to only fix the queue management in
fcoe_check_wait_queue, where my first patch added locking to the transmit
path even when the pending queue was not in use.
This patch continues to use fcoe_pending_queue.qlen instead of introducing a
new length counter, but takes precautions to ensure it never drops to 0 before
the final frame in the queue has successfully been passed to the netdev qdisc
layer. It also includes some cleanup of fcoe_check_wait_queue and removes the
fcoe_insert_wait_queue(_head) wrapper functions.
Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
frames followed by these errors in log.
[sdp] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE,SUGGEST_OK
[sdp] Sense Key : Aborted Command [current]
[sdp] Add. Sense: Data phase error
This was causing some test apps to exit due to write failure under heavy
load.
This was due to a race around adding and removing tx frame skb in
fcoe_pending_queue, Chris Leech helped me to find that brief unlocking
period when pulling skb from fcoe_pending_queue in various contexts
(fcoe_watchdog and fcoe_xmit) and then adding skb back into fcoe_pending_queue
up on a failed fcoe_start_io could change skb/tx frame order in
fcoe_pending_queue. Thanks Chris.
This patch allows only single context to pull skb from fcoe_pending_queue
at any time to prevent above described ordering issue/race by use of
fcoe_pending_queue_active flag.
This patch simplified fcoe_watchdog with modified fcoe_check_wait_queue by
use of FCOE_LOW_QUEUE_DEPTH instead previously used several conditionals
to clear and set lp->qfull.
I think FCOE_MAX_QUEUE_DEPTH with FCOE_LOW_QUEUE_DEPTH will work better
in re/setting lp->qfull and these could be fine tuned for performance.
Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Use kfree_skb instead of kfree for struct sk_buff pointers.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
The registration function shouldn't initialize the mutex or
list head. The fcoe SW transport should initialize itself
before registering.
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Use helper functions for watchdog timer setup.
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Comment from "Andrew Morton <akpm@linux-foundation.org>"
> +{
> + return (struct fcoe_softc *)lport_priv(lp);
unneeded/undesirable cast of void*. There are probably zillions of
instances of this - there always are.
This whole inline function was unnecessary. The FCoE layer knows
that it's data structure is stored in the lport private data, it
can just access it from lport_priv().
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
1) There were a few functions with a strange layout, i.e. all
arguments on the second line, when not necessary.
Where ever possible I moved the return value to the same line
as the function name. However, when the line was too long
to have a single argument on the same line I moved the
return value to above line. For example:
<short return> <function name>(<arg 1>, <arg2>)
and
<very long return value>
<function name>(<arg1>,
<arg2>)
2) Removed one extra whitespace line
3) Fixed two typos
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
1) Added '()' for function names in kerneldoc comments
2) Changed comment bookends from '**/' to '*/'. The comment on the the
mailing list was that '**/' "is consistently unconventional. Not
wrong, just odd." The Documentation/kernel-doc-nano-HOWTO.txt
states that kerneldoc comment blocks should end with '**/' but most
(if not all) instance I found under drivers/scsi/ were only using
the '*/' so I converted to that style.
3) Removed incorrect linebreaks in kerneldoc comments where found
4) Removed a few unnecessary blank comment lines in kerneldoc comment
blocks
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
The fcoe_xmit could call fc_pause in case the pending skb queue len is larger
than FCOE_MAX_QUEUE_DEPTH, the fc_pause was trying to grab lport->lp_muex to
change lport->link_status and that had these issues :-
1. The fcoe_xmit was getting called with bh disabled, thus causing
"BUG: scheduling while atomic" when grabbing lport->lp_muex with bh disabled.
2. fc_linkup and fc_linkdown function calls lport_enter function with
lport->lp_mutex held and these enter function in turn calls fcoe_xmit to send
lport related FC frame, e.g. fc_linkup => fc_lport_enter_flogi to send flogi
req. In this case grabbing the same lport->lp_mutex again in fc_puase from
fcoe_xmit would cause deadlock.
The lport->lp_mutex was used for setting FC_PAUSE in fcoe_xmit path but
FC_PAUSE bit was not used anywhere beside just setting and clear this
bit in lport->link_status, instead used a separate field qfull in fc_lport
to eliminate need for lport->lp_mutex to track pending queue full condition
and in turn avoid above described two locking issues.
Also added check for lp->qfull in fc_fcp_lport_queue_ready to trigger
SCSI_MLQUEUE_HOST_BUSY when lp->qfull is set to prevent more scsi-ml cmds
while lp->qfull is set.
This patch eliminated FC_LINK_UP and FC_PAUSE and instead used dedicated
fields in fc_lport for this, this simplified all related conditional
code.
Also removed fc_pause and fc_unpause functions and instead used newly added
lport->qfull directly in fcoe.
Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This structure may not be defined if CONFIG_MODULE=n, so never deref
it. Change uses of module->name to module_name(module) and corrects
some dyslexic printks and docbook comments.
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Encapsulation protocol for running Fibre Channel over Ethernet interfaces.
Creates virtual Fibre Channel host adapters using libfc.
This layer is the LLD to the scsi-ml. It allocates the Scsi_Host, utilizes
libfc for Fibre Channel protocol processing and interacts with netdev to
send/receive Ethernet packets.
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Robert Love
Chris Leech
Vasu Dev
Roel Kluin
James Bottomley