ondemand selects the minimum frequency that can retire
a workload with negligible idle time -- ideally resulting in the highest
performance/power efficiency with negligible performance impact.
But on some systems and some workloads, this algorithm
is more performance biased than necessary, and
de-tuning it a bit to allow some performance impact
can save measurable power.
This patch adds a "powersave_bias" tunable to ondemand
to allow it to reduce its target frequency by a specified percent.
By default, the powersave_bias is 0 and has no effect.
powersave_bias is in units of 0.1%, so it has an effective range
of 1 through 1000, resulting in 0.1% to 100% impact.
In practice, users will not be able to detect a difference between
0.1% increments, but 1.0% increments turned out to be too large.
Also, the max value of 1000 (100%) would simply peg the system
in its deepest power saving P-state, unless the processor really has
a hardware P-state at 0Hz:-)
For example, If ondemand requests 2.0GHz based on utilization,
and powersave_bias=100, this code will knock 10% off the target
and seek a target of 1.8GHz instead of 2.0GHz until the
next sampling. If 1.8 is an exact match with an hardware frequency
we use it, otherwise we average our time between the frequency
next higher than 1.8 and next lower than 1.8.
Note that a user or administrative program can change powersave_bias
at run-time depending on how they expect the system to be used.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi at intel.com>
Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy at intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Try to make dbs_check_cpu() call on all CPUs at the same jiffy.
This will help when multiple cores share P-states via Hardware Coordination.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi at intel.com>
Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy at intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
In my quest to try and figure out why test 14 (control write) doesn't
work with my EZ-USB board, I noticed that sometimes testusb reported
no error even though the kernel log complained "byte 0 is 0 not 2" etc.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
I write a patch for ipaq.c.
Would you like to add upstream tree ?
This patch enables a support of "SHARP W-ZERO3(WS004SH)" and "SHARP W-ZERO3[es](WS007SH)".
From: Norihiko Tomiyama <norihiko.tomiyama@ctc-g.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
appletouch uses urb->transfer_dma after having freed the urb, this shows
up only if the system is compiled with slab debugging. This patch fixes
it by reordering the free calls.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Vojtech Pavlik <vojtech@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch has removed a unbalanced #endif from ohci-au1xxx.c .
Please apply before 2.6.18 release.
Error message was:
In file included from drivers/usb/host/ohci-hcd.c:909:
drivers/usb/host/ohci-au1xxx.c:113:2: #endif without #if
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as763) adds an unusual_devs entry for the A-VOX WSX-300ER MP3
player.
From: David Kuehling <dvdkhlng@gmx.de>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Make pciehp build on powerpc
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When destroying a QP, mthca locks both the QP's send CQ and receive
CQ. However, the following scenario is perfectly valid:
QP_a: send_cq == CQ_x, recv_cq == CQ_y
QP_b: send_cq == CQ_y, recv_cq == CQ_x
The old mthca code simply locked send_cq and then recv_cq, which in
this case could lead to an AB-BA deadlock if QP_a and QP_b were
destroyed simultaneously.
We can fix this by changing the locking code to lock the CQ with the
lower CQ number first, which will create a consistent lock ordering.
Also, the second CQ is locked with spin_lock_nested() to tell lockdep
that we know what we're doing with the lock nesting.
This bug was found by lockdep.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The fence bit needs to be set in the doorbell too, not just the WQE.
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The dasd function dasd_set_uid calls kzalloc while holding the
dasd_devmap_lock. Rearrange the code to do the memory allocation
outside the lock.
Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
On the 88E805X chipsets (used in laptops), the PHY was not getting powered
out of shutdown properly. The variable reg1 was getting reused incorrectly.
This is probably the cause of the bug.
http://bugzilla.kernel.org/show_bug.cgi?id=6471
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Hi,
Reading the Intel VSC and AHCI it seems like writing 0x302 is incorrect.
The only valid values are 4, 1 and 0. Writing 4 disables the
PHY.
Signed-off-by: Martin Hicks <mort@bork.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
pdc_adma was overlooked and broken by the irq-pio patch:
Only HSM_ST_LAST interrupts should be delivered to this LLDD.
Adding ATA_FLAG_PIO_POLLING to pdc_adma fixes the problem (temporarily),
before we convert the irq handler of pdc_adma to handle all interrupts.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement dummy port which can be requested by setting appropriate bit
in probe_ent->dummy_port_mask. The dummy port is used as placeholder
for stolen legacy port. This allows libata to guarantee that
index_of(ap) == ap->port_no == actual_device_port_no, and thus to
remove error-prone ap->hard_port_no.
As it's used only when one port of a legacy controller is reserved by
some other entity (e.g. IDE), the focus is on keeping the added *code*
complexity at minimum, so dummy port allocates all libata core
resources and acts as a normal port. It just has all dummy port_ops.
This patch only implements dummy port. The following patch will make
libata use it for stolen legacy ports.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Kill host_set->next
Fix simplex support
Allow per platform setting of IDE legacy bases
Some of this can be tidied further later on, in particular all the
legacy port gunge belongs as a PCI quirk/PCI header decode to understand
the special legacy IDE rules in the PCI spec.
Longer term Jeff also wants to move the request_irq/free_irq out of core
which will make this even cleaner.
tj: folded in three followup patches - ata_piix-fix, broken-arch-fix
and fix-new-legacy-handling, and separated per-dev xfermask into
separate patch preceding this one. Folded in fixes are...
* ata_piix-fix: fix build failure due to host_set->next removal
* broken-arch-fix: add missing include/asm-*/libata-portmap.h
* fix-new-legacy-handling:
* In ata_pci_init_legacy_port(), probe_num was incorrectly
incremented during initialization of the secondary port and
probe_ent->n_ports was incorrectly fixed to 1.
* Both legacy ports ended up having the same hard_port_no.
* When printing port information, both legacy ports printed
the first irq.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Implement per-dev xfermask. libata used to determine xfermask
per-port - the fastest mode of the slowest device on the port. This
patch enables per-dev xfermask.
Original patch is from Alan Cox <alan@redhat.com>. The following
changes are made by me.
* simplex warning message is added
* remove disabled device handling code which is never invoked
(originally for choosing port-wide lowest PIO mode)
Cc: Alan Cox <alan@redhat.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>
s/ata_host_add/ata_port_add/
s/ata_host_init/ata_port_init/
libata naming got stuck in the middle of a Great Renaming:
ata_host -> ata_port
ata_host_set -> ata_host
To eliminate confusion, let's just give up for now, and simply ensure
that things are internally consistent.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Update ata_host_init() such that it only initializes SCSI host related
stuff and doesn't call into ata_port_init(), and rename it to
ata_port_init_shost().
Signed-off-by: Tejun Heo <htejun@gmail.com>
When the IDE fix for Jmicron went in one piece went walking somewhere
(send log shows my end somehow). Without this sometimes you get an oops
on boot.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The request queue flush function of the dasd driver has to dequeue
the requests first and then call the end request function. Otherwise
a kernel bug in ll_rw_block.c might get triggered.
Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
SCSI EH locks door if sdev->locked is set. Sometimes door lock
command fails continuously (e.g. when medium is not present) and as
libata uses EH to acquire sense data, this easily creates a loop where
a failed lock door invokes EH and EH issues lock door on completion.
This patch clears sdev->locked on door lock failure to break this
loop. This problem has been spotted and diagnosed by Unicorn Chang
<uchang@tw.ibm.com>.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fix a sata debug print statement that still uses an old variable name.
Signed-off-by: Keith Owens <kaos@ocs.com.au>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Initial IRQ mask clearing is done by libata-core by freezing all ports
prior to requesting IRQ. Remove redundant IRQ clearing from
init_controller().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Dummy RDMA are always enabled on device startup since commit
9a71db721a (to work around buggy
PCIe chipsets which do not implement resending properly). But,
we also need to always re-enable them when resuming the device.
Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The following patch enhances libata to allow SAS device drivers
to utilize libata to talk to SATA devices. It introduces some
new APIs which allow libata to be used without allocating a
virtual scsi host.
New APIs:
ata_sas_port_alloc - Allocate an ata_port
ata_sas_port_init - Initialize an ata_port (probe device, etc)
ata_sas_port_destroy - Free an ata_port allocated by ata_sas_port_alloc
ata_sas_slave_configure - configure scsi device
ata_sas_queuecmd - queue a scsi command, similar to ata_scsi_queuecomand
These new APIs can be used either directly by a SAS LLDD or could be used
by the SAS transport class.
Possible usage for a SAS LLDD would be:
scsi_scan_host
target_alloc
ata_sas_port_alloc
slave_alloc
ata_sas_port_init
slave_configure
ata_sas_slave_configure
Commands received by the LLDD for SATA devices would call ata_sas_queuecmd.
Device teardown would occur with:
slave_destroy
port_disable
target_destroy
ata_sas_port_destroy
Signed-off-by: Brian King <brking@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
