Commit Graph

63741 Commits

Author SHA1 Message Date
Ingo Molnar c7e9b5b293 sched: remove the 'u64 now' parameter from update_stats_curr_end()
remove the 'u64 now' parameter from update_stats_curr_end().

( identity transformation that causes no change in functionality. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:48 +02:00
Ingo Molnar 19b6a2e370 sched: remove the 'u64 now' parameter from update_stats_dequeue()
remove the 'u64 now' parameter from update_stats_dequeue().

( identity transformation that causes no change in functionality. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:48 +02:00
Ingo Molnar 79303e9e02 sched: remove the 'u64 now' parameter from update_stats_curr_start()
remove the 'u64 now' parameter from update_stats_curr_start().

( identity transformation that causes no change in functionality. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar 9ef0a9615b sched: remove the 'u64 now' parameter from update_stats_wait_end()
remove the 'u64 now' parameter from update_stats_wait_end().

( identity transformation that causes no change in functionality. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar eac55ea376 sched: remove the 'u64 now' parameter from __update_stats_wait_end()
remove the 'u64 now' parameter from __update_stats_wait_end().

( identity transformation that causes no change in functionality. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar d2417e5a3e sched: remove the 'u64 now' parameter from update_stats_enqueue()
remove the 'u64 now' parameter from update_stats_enqueue().

( identity transformation that causes no change in functionality. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar 5870db5b83 sched: remove the 'u64 now' parameter from update_stats_wait_start()
remove the 'u64 now' parameter from update_stats_wait_start().

( identity transformation that causes no change in functionality. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar b7cc089657 sched: remove the 'u64 now' parameter from update_curr()
remove the 'u64 now' parameter from update_curr().

( identity transformation that causes no change in functionality. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar 5cef9eca38 sched: remove the 'u64 now' parameter from print_cfs_rq()
remove the 'u64 now' parameter from print_cfs_rq().

( identity transformation that causes no change in functionality. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar d281918d7c sched: remove 'now' use from assignments
change all 'now' timestamp uses in assignments to rq->clock.

( this is an identity transformation that causes no functionality change:
  all such new rq->clock is necessarily preceded by an update_rq_clock()
  call. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar eb59449400 sched: remove __rq_clock()
remove the (now unused) __rq_clock() function.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar c1b3da3ecd sched: eliminate __rq_clock() use
eliminate __rq_clock() use by changing it to:

   __update_rq_clock(rq)
   now = rq->clock;

identity transformation - no change in behavior.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar 2ab81159fa sched: remove rq_clock()
remove the now unused rq_clock() function.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar a8e504d2a5 sched: eliminate rq_clock() use
eliminate rq_clock() use by changing it to:

   update_rq_clock(rq)
   now = rq->clock;

identity transformation - no change in behavior.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:47 +02:00
Ingo Molnar b04a0f4c16 sched: add [__]update_rq_clock(rq)
add the [__]update_rq_clock(rq) functions. (No change in functionality,
just reorganization to prepare for elimination of the heavy 64-bit
timestamp-passing in the scheduler.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Peter Williams a4ac01c36e sched: fix bug in balance_tasks()
There are two problems with balance_tasks() and how it used:

1. The variables best_prio and best_prio_seen (inherited from the old
move_tasks()) were only required to handle problems caused by the
active/expired arrays, the order in which they were processed and the
possibility that the task with the highest priority could be on either.
  These issues are no longer present and the extra overhead associated
with their use is unnecessary (and possibly wrong).

2. In the absence of CONFIG_FAIR_GROUP_SCHED being set, the same
this_best_prio variable needs to be used by all scheduling classes or
there is a risk of moving too much load.  E.g. if the highest priority
task on this at the beginning is a fairly low priority task and the rt
class migrates a task (during its turn) then that moved task becomes the
new highest priority task on this_rq but when the sched_fair class
initializes its copy of this_best_prio it will get the priority of the
original highest priority task as, due to the run queue locks being
held, the reschedule triggered by pull_task() will not have taken place.
  This could result in inappropriate overriding of skip_for_load and
excessive load being moved.

The attached patch addresses these problems by deleting all reference to
best_prio and best_prio_seen and making this_best_prio a reference
parameter to the various functions involved.

load_balance_fair() has also been modified so that this_best_prio is
only reset (in the loop) if CONFIG_FAIR_GROUP_SCHED is set.  This should
preserve the effect of helping spread groups' higher priority tasks
around the available CPUs while improving system performance when
CONFIG_FAIR_GROUP_SCHED isn't set.

Signed-off-by: Peter Williams <pwil3058@bigpond.net.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Ingo Molnar aea25401c3 sched: document nice levels
Document the design thinking behind nice levels.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Alexey Dobriyan e0361851e5 sched: remove binary sysctls from kernel.sched_domain
kernel.sched_domain hierarchy is under CTL_UNNUMBERED and thus
unreachable to sysctl(2). Generating .ctl_number's in such situation is
not useful.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Ingo Molnar fd8bb43e27 sched: delta_exec accounting fix
small delta_exec accounting fix: increase delta_exec and increase
sum_exec_runtime even if the task is not on the runqueue anymore.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Ingo Molnar c5dcfe72aa sched: clean up delta_mine
cleanup: delta_mine is an unsigned value.

no code impact:

   text    data     bss     dec     hex filename
   27823    2726      16   30565    7765 sched.o.before
   27823    2726      16   30565    7765 sched.o.after

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Ingo Molnar 8e717b194c sched: schedule() speedup
speed up schedule(): share the 'now' parameter that deactivate_task()
was calculating internally.

( this also fixes the small accounting window between the deactivate
  call and the pick_next_task() call. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Ingo Molnar 7bfd048587 sched: uninline rq_clock()
uninline rq_clock() to save 263 bytes of code:

   text    data     bss     dec     hex filename
   39561    3642      24   43227    a8db sched.o.before
   39298    3642      24   42964    a7d4 sched.o.after

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Josh Triplett 291ae5a120 sched: mark print_cfs_stats static
sched_fair.c defines print_cfs_stats, and sched_debug.c uses it, but sched.c
includes both sched_fair.c and sched_debug.c, so all the references to
print_cfs_stats occur in the same compilation unit.  Thus, mark
print_cfs_stats static.

Eliminates a sparse warning:
warning: symbol 'print_cfs_stats' was not declared. Should it be static?

Signed-off-by: Josh Triplett <josh@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Ulrich Drepper 9531b62f5e sched: clean up sched_getaffinity()
here's another tiny cleanup.  The generated code is not affected (gcc is
smart enough) but for people looking over the code it is just irritating
to have the extra conditional.

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Thomas Voegtle 5f5d3aa15b sched: mention CONFIG_SCHED_DEBUG in documentation
a little hint to switch on CONFIG_SCHED_DEBUG should be given.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Peter Williams 4301065920 sched: simplify move_tasks()
The move_tasks() function is currently multiplexed with two distinct
capabilities:

1. attempt to move a specified amount of weighted load from one run
queue to another; and
2. attempt to move a specified number of tasks from one run queue to
another.

The first of these capabilities is used in two places, load_balance()
and load_balance_idle(), and in both of these cases the return value of
move_tasks() is used purely to decide if tasks/load were moved and no
notice of the actual number of tasks moved is taken.

The second capability is used in exactly one place,
active_load_balance(), to attempt to move exactly one task and, as
before, the return value is only used as an indicator of success or failure.

This multiplexing of sched_task() was introduced, by me, as part of the
smpnice patches and was motivated by the fact that the alternative, one
function to move specified load and one to move a single task, would
have led to two functions of roughly the same complexity as the old
move_tasks() (or the new balance_tasks()).  However, the new modular
design of the new CFS scheduler allows a simpler solution to be adopted
and this patch addresses that solution by:

1. adding a new function, move_one_task(), to be used by
active_load_balance(); and
2. making move_tasks() a single purpose function that tries to move a
specified weighted load and returns 1 for success and 0 for failure.

One of the consequences of these changes is that neither move_one_task()
or the new move_tasks() care how many tasks sched_class.load_balance()
moves and this enables its interface to be simplified by returning the
amount of load moved as its result and removing the load_moved pointer
from the argument list.  This helps simplify the new move_tasks() and
slightly reduces the amount of work done in each of
sched_class.load_balance()'s implementations.

Further simplification, e.g. changes to balance_tasks(), are possible
but (slightly) complicated by the special needs of load_balance_fair()
so I've left them to a later patch (if this one gets accepted).

NB Since move_tasks() gets called with two run queue locks held even
small reductions in overhead are worthwhile.

[ mingo@elte.hu ]

this change also reduces code size nicely:

   text    data     bss     dec     hex filename
   39216    3618      24   42858    a76a sched.o.before
   39173    3618      24   42815    a73f sched.o.after

Signed-off-by: Peter Williams <pwil3058@bigpond.net.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:46 +02:00
Ingo Molnar f1a438d813 sched: reorder update_cpu_load(rq) with the ->task_tick() call
Peter Williams suggested to flip the order of update_cpu_load(rq) with
the ->task_tick() call. This is a NOP for the current scheduler (the
two functions are independent of each other), ->task_tick() might
create some state for update_cpu_load() in the future (or in PlugSched).

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:45 +02:00
Ingo Molnar 0915c4e89d sched: batch sleeper bonus
batch up the sleeper bonus sum a bit more. Anything below
sched-granularity is too small to make a practical difference
anyway.

this optimization reduces the math in high-frequency scheduling
scenarios.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-09 11:16:45 +02:00
Linus Torvalds 4a2a4df7b6 Merge master.kernel.org:/home/rmk/linux-2.6-arm
* master.kernel.org:/home/rmk/linux-2.6-arm:
  [ARM] rpc: update defconfig
  [ARM] pata_icside: fix the FIXMEs
  [ARM] 4542/1: AT91: include atmel_lcdc.h in at91sam926{1,3}_devices.c
  [ARM] 4541/1: iop: defconfig updates
  [ARM] 4531/1: remove is_in_rom() protptype
2007-08-06 18:31:43 -07:00
Linus Torvalds f27eb3afe8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  [CRYPTO] api: fix writting into unallocated memory in setkey_aligned
2007-08-06 18:25:06 -07:00
Al Viro 6f605d83dd take sched_debug.c out of nasal demon territory
C99 6.10.3[11]: preprocessing directive within the argument list of
macro invocation => undefined behaviour.  Don't do that...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-06 18:22:27 -07:00
Rusty Russell cc1ff43b70 Enable lguest drivers in Kconfig
Lguest drivers need to default to "Y" otherwise they're never selected
for new builds.  (We don't bother prompting, because they're less than
4k combined, and implied by selecting lguest support).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-06 18:21:15 -07:00
Avi Kivity bac27d35cb KVM: x86 emulator: fix debug reg mov instructions
More fallout from the writeback fixes: debug register transfer
instructions do their own writeback and thus need to disable the general
writeback mechanism.

This fixes oopses and some guest failures on AMD machines (the Intel
variant decodes the instruction in hardware and thus does not need
emulation).

Cc: Alistair John Strachan <alistair@devzero.co.uk>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-06 17:54:41 -07:00
Linus Torvalds 9e865f58da Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
  [NETFILTER]: Add xt_statistic.h to the header list for usermode programs
  [BNX2]: Fix suspend/resume problem.
  [TG3]: Fix suspend/resume problem.
2007-08-06 17:52:56 -07:00
Linus Torvalds 111e2a513b Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6
* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6:
  [SPARC32]: Fix build.
2007-08-06 17:52:42 -07:00
Linus Torvalds bced137384 Merge master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6: (32 commits)
  [SCSI] aacraid: prevent panic on adapter resource failure
  [SCSI] aha152x: use data accessors and !use_sg cleanup
  [SCSI] aha152x: Fix check_condition code-path
  [SCSI] aha152x: Clean Reset path
  [SCSI] aha152x: preliminary fixes and some comments
  [SCSI] aha152x: use bounce buffer
  [SCSI] aha152x: fix debug mode symbol conflict
  [SCSI] sd: disentangle barriers in SCSI
  [SCSI] lpfc : scsi command accessor fix for 8.2.2
  [SCSI] qlogicpti: Some cosmetic changes
  [SCSI] lpfc 8.2.2 : Change version number to 8.2.2
  [SCSI] lpfc 8.2.2 : Style cleanups
  [SCSI] lpfc 8.2.2 : Miscellaneous Bug Fixes
  [SCSI] lpfc 8.2.2 : Miscellaneous management and logging mods
  [SCSI] lpfc 8.2.2 : Rework the lpfc_printf_log() macro
  [SCSI] lpfc 8.2.2 : Attribute and Parameter splits for vport and physical port
  [SCSI] lpfc 8.2.2 : Fix locking around HBA's port_list
  [SCSI] lpfc 8.2.2 : Error messages and debugfs updates
  [SCSI] initialize shost_data to zero
  [SCSI] mptsas: add SMP passthrough support via bsg
  ...
2007-08-06 17:48:34 -07:00
Dave Airlie 21f1628927 drm/i915: Fix i965 secured batchbuffer usage
This 965G and above chipsets moved the batch buffer non-secure bits to
another place. This means that previous drm's allowed in-secure batchbuffers
to be submitted to the hardware from non-privileged users who are logged
into X and and have access to direct rendering.

Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-06 17:46:23 -07:00
Russell King 6e7d934060 [ARM] rpc: update defconfig
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-08-06 16:48:49 +01:00
Russell King eba84481c7 [ARM] pata_icside: fix the FIXMEs
Alan Cox suggested that the solution to the FIXMEs in pata_icside is
to use a private postreset method to detect the lack of devices on a
port, and in such a case, disable the interrupt for the port.

This patch implements such a method, and removes the hard coded
disable of port 0.  Tested as working.

Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-08-06 16:10:54 +01:00
Sebastian Siewior 0681717678 [CRYPTO] api: fix writting into unallocated memory in setkey_aligned
setkey_unaligned() commited in ca7c39385c
overwrites unallocated memory in the following memset() because
I used the wrong buffer length.

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-08-06 15:33:56 +08:00
Chuck Ebbert be1b685fe6 [NETFILTER]: Add xt_statistic.h to the header list for usermode programs
Add xt_statistic.h to the list of headers to install.

Apparently needed to build newer versions of iptables.

Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-08-04 21:18:16 -07:00
Mark Fortescue c8154c8a9a [SPARC32]: Fix build.
Correct incorrect removal of asm-generic/fcntl.h from asm-sparc/fcntl.h by 
commit 6ba60d2195.

Signed-off-by: Mark Fortescue <mark@mtfhpc.demon.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-08-04 21:17:18 -07:00
Jan Altenberg b8b786098b [ARM] 4542/1: AT91: include atmel_lcdc.h in at91sam926{1,3}_devices.c
- Include atmel_lcdc.h in at91sam926{1,3}_devices.c

Signed-off-by: Jan Altenberg <jan.altenberg@linutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-08-04 22:13:48 +01:00
Dan Williams 581cf23b51 [ARM] 4541/1: iop: defconfig updates
With the availability of the iop-adma driver iop platforms can now use
their offload engines for md-raid5 (copy+xor) and net-dma (tcp receive
copy) offload.

Cc: Lennert Buytenhek <kernel@wantstofly.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-08-04 22:13:47 +01:00
Greg Ungerer 0a8626a475 [ARM] 4531/1: remove is_in_rom() protptype
Remove unused is_in_rom() function prototype.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-08-04 22:13:43 +01:00
Salyzyn, Mark 2b053729a8 [SCSI] aacraid: prevent panic on adapter resource failure
If the driver fails to allocate the contiguous (DMAable) memory for
system reasons, we fail to load the instance, but then we try to free
the <nul> allocation in the cleanup code and we get a panic in
pci_free_consistent(). This is reported against an older kernel, hope
this is relevant for latest/greatest.

Signed-off-by: Mark Salyzyn <aacraid@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-08-04 09:46:43 -05:00
Boaz Harrosh 2338545aaf [SCSI] aha152x: use data accessors and !use_sg cleanup
And finally this is the regular !use_sg cleanup
and use of data accessors.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-08-04 09:14:49 -05:00
Boaz Harrosh 45333ffa6f [SCSI] aha152x: Fix check_condition code-path
check_condition code-path was similar but more
complicated to Reset. It went like this:

  1. extra space was allocated at aha152x_scdata for mirroring
    scsi_cmnd members.
  2. At aha152x_internal_queue() every not check_condition
    (REQUEST_SENSE) command was copied to above members in
    case of error.
  3. At busfree_run() in the DONE_CS phase if a Status of
    SAM_STAT_CHECK_CONDITION was detected. The command was
    re-queued Internally using aha152x_internal_queue(,,check_condition,)
    The old command members are over written with the
    REQUEST_SENSE info.
  4. At busfree_run() in the DONE_CS phase again. If it is a
    check_condition command, info was restored from mirror
    made at first call to aha152x_internal_queue() (see 2)
    and the command is completed.

What I did is:

  1. Allocate less space in aha152x_scdata only for the 16-byte
    original command. (which is actually not needed by scsi-ml
    anymore at this stage. But this is to much knowledge of scsi-ml)
  2. If Status == SAM_STAT_CHECK_CONDITION, then like before
     re-queue a REQUEST_SENSE command. But only now save original
     command members. (Less of them)
  3. In aha152x_internal_queue(), just like for Reset, use the
    check_condition hint to set differently the working members.
    execute the command.
  4. At busfree_run() in the DONE_CS phase again. restore needed
     members.

While at it. This patch fixes a BUG. Old code when sending
a REQUEST_SENSE for a failed command. Would than return with
cmd->resid == 0 which was the status of the REQUEST_SENSE.
The failing command resid was lost. And when would resid
be interesting if not on a failing command?

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-08-04 09:14:24 -05:00
Boaz Harrosh 66acdb0309 [SCSI] aha152x: Clean Reset path
What Reset code was doing:  Save command's important/dangerous
Info on stack. NULL those members from scsi_cmnd.
Issue a Reset. wait for it to finish than restore members
and return.

What I do is save or NULL nothing. But use the "resetting"
hint in aha152x_internal_queue() to NULL out working members
and leave struct scsi_cmnd alone.

The indent here looks funny but it will change/drop in last
patch and it is clear this way what changed.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-08-04 09:13:28 -05:00
Boaz Harrosh 0ceb47987d [SCSI] aha152x: preliminary fixes and some comments
hunk by hunk:
  - CHECK_CONDITION is what happens to cmnd->status >> 1
    or after status_byte() macro. But here it is used
    directly on status which means 0x1 which is an undefined
    bit in the standard. And is a status that will never
    return from a target.

  - in busfree_run at the DONE_SC phase we have 3 distinct
    operation:
	1-if(DONE_SC->SCp.phase & check_condition)
          The REQUEST_SENSE command return.
          - Restore original command
	  - Than continue to operation 3.
	2-if(DONE_SC->SCp.Status==SAM_STAT_CHECK_CONDITION)
          A regular command returned with a status.
	  - Internally re-Q a REQUEST_SENSE.
	  - Do not do operation 3.
	3-
	  - Complete the command and return it to scsi-ml
     So the 0x2 in both these operations (1,2) means the scsi
     check-condition status, hence SAM_STAT_CHECK_CONDITION

  - Here the code asks about !(DONE_SC->SCp.Status & not_issued)
    but "not_issued" is an enum belonging to the "phase" member
    and not to the Status returned from target. The reason this
    works is because not_issued==1 and Also CHECK_CONDITION==1
    (remember from hunk 1). So actually the code was asking
    !(DONE_SC->SCp.Status & CHECK_CONDITION). Which means
    "Has the status been read from target yet?"
    Staus is read at status_run(). "not_issued" is
    cleared in seldo_run() which is usually earlier than
    status_run().

  So this patch does nothing as far as assembly is concerned
  but it does let the reader understand what is going on.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-08-04 09:12:48 -05:00