Some ATA/ATAPI devices act weirdly after the link is put into slumber
mode. Some hang completely requiring physical power removal while
others fail to wake up till the link is hardreset a couple of times.
The addition of slumber on power down was never driven by real need.
It just followed what ahci spec said literally. The spec itself seems
faulty in that it doesn't consider devices (not controllers) which
don't support link powersaving mode.
Theory never matches reality when it comes to dark allys of cheap
ATA/ATAPI world. It's just unrealistic to expect vendors to test
rarely used link powersaving feature rigorously. This patch makes
ahci more friendly to the coldness of reality.
This shouldn't have any negative effect - when suspend operation
succeeds, we power off the whole machine; otherwise, we wake up
everything. I can't see any reason to be so elaborate with powering
down the link in the first place.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Several people reported issues with certain drive commands timing out on
sata_nv controllers running in ADMA mode. The commands in question were
non-DMA-mapped commands, usually FLUSH CACHE or FLUSH CACHE EXT.
From experimentation it appears that the NV_INT_DEV indication isn't
always set when a legitimate command completion interrupt is received on
a legacy-mode command, at least not on these controllers in ADMA mode.
When a command is pending on the port, force the flag on always in the
irq_stat value before calling nv_host_intr so that the drive busy state
is always checked by ata_host_intr.
This also fixes some questionable code in nv_host_intr which called
ata_check_status when a command was pending and ata_host_intr returned
"unhandled". If the device interrupted at just the wrong time this could
cause interrupts to be lost.
Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
As with JMicron controllers, ULi M5288 sets interface fatal error bit
on device error including ATAPI CC. This makes libata hardreset the
port on ATAPI CC thus making it impossible to use. Ignore interface
fatal error bit on ULi M5288. This fixes bugzilla bug #7837.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
We are doing ->buf_prepare(buf) before adding buf to q->stream list. This
means that videobuf_qbuf() should not try to re-add a STATE_PREPARED buffer.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This changes a few mentions of my email address to point to the new one,
leaving things like old copyright messages alone.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change my email address to reflect OSDL merger.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
[ The irony. Somebody still has his sign-off message hardcoded
in a script or his brainstem ;^]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Any newly added irq handler may obviously make any old spurious irq
status invalid, since the new handler may well be the thing that is
supposed to handle any interrupts that came in.
So just clear the statistics when adding handlers.
Pointed-out-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As written, sys_shmget will return ENOSPC when one page is still
available for allocation. This patch corrects the test.
Signed-off-by: Guy Streeter <guy.streeter+lkml@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
--
* 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband:
IB/ehca: Fix mismatched spin_unlock in irq handler
IB/ehca: Fix improper use of yield() with spinlock held
IB/srp: Check match_strdup() return
memset() after kmalloc() on size * 8 would better be on size * 8, not
just size; fixed by switching to kcalloc() - it's more idiomatic anyway.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
while lock-profiling the -rt kernel i noticed weird contention during
mmap-intense workloads, and the tracer showed the following gem, in one
of our MM hotpaths:
threaded-2771 1.... 65us : sys_munmap (sysenter_do_call)
threaded-2771 1.... 66us : profile_munmap (sys_munmap)
threaded-2771 1.... 66us : blocking_notifier_call_chain (profile_munmap)
threaded-2771 1.... 66us : rt_down_read (blocking_notifier_call_chain)
ouch! a global rw-semaphore taken in one of the most performance-
sensitive codepaths of the kernel. And i dont even have oprofile
enabled! All distro kernels have CONFIG_PROFILING enabled, so this
scalability problem affects the majority of Linux users.
The fix is to enhance blocking_notifier_call_chain() to only take the
lock if there appears to be work on the call-chain.
With this patch applied i get nicely saturated system, and much higher
munmap performance, on SMP systems.
And as a bonus this also fixes a similar scalability bottleneck in the
thread-exit codepath: profile_task_exit() ...
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/netdev-2.6:
NetXen: Use pci_register_driver() instead of pci_module_init() in init_module
NetXen: Firmware check modifications
ehea: Fixed possible nullpointer access
ehea: Added logging off associated errors
ehea: Improved logging of permission issues
ehea: New method to determine number of available ports
ehea: Modified initial autoneg state determination
ehea: Fixing firmware queue config issue
ehea: Fixed wrong dereferencation
PHY: Export phy ethtool helpers
modify 3c589_cs to be SMP safe
* 'kill-jffs-prep' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6:
Note that JFFS (v1) is to be deleted, in feature-removal-schedule.txt
A flag was recently added to the elevator code to avoid
performing an unplug when reuests are being re-queued.
The goal of this flag was to avoid a deep recursion that
can occur when re-queueing requests after a SCSI device/host
reset. See http://lkml.org/lkml/2006/5/17/254
However, that fix added the flag near the bottom of a case
statement, where an earlier break (in an if statement) could
transport one out of the case, without setting the flag.
This patch sets the flag earlier in the case statement.
I re-discovered the deep recursion recently during testing;
I was told that it was a known problem, and the fix to it was
in the kernel I was testing. Indeed it was ... but it didn't
fix the bug. With the patch below, I no longer see the bug.
Signed-off by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SMTC pseudo-interrupts between TCs are deferred and queued if the target
TC is interrupt-inhibited (IXMT). In the first SMTC prototypes, these
queued IPIs were serviced on return to user mode, or on entry into the
kernel idle loop. The INSTANT_REPLAY option dispatches them as part of
local_irq_restore() processing, which adds runtime overhead (hence the
option to turn it off), but ensures that IPIs are handled promptly even
under heavy I/O interrupt load.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Mohan Kumar suggested making kexec-tools-testing.tar.gz a link to the
latest version. I have done this and this patch updates the documentation
accordingly.
Signed-off-by: Simon Horman <horms@verge.net.au>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun Heo
Robert Hancock
Oleg Nesterov
Linus Torvalds
Stephen Hemminger
Guy Streeter
Al Viro
Ingo Molnar
Linas Vepstas
Yoichi Yuasa
Ralf Baechle
Jeff Chua
Horms