It appears that with the U3 northbridge, if the processor is in NAP
mode the whole time while waiting for an SMU command to complete,
then the SMU will fail. It could be related to the weird backward
mechanism the SMU uses to get to system memory via i2c to the
northbridge that doesn't operate properly when the said bridge is
in napping along with the CPU. That is on U3 at least, U4 doesn't
seem to be affected.
This didn't show before NO_HZ as the timer wakeup was enough to make
it work it seems, but that is no longer the case.
This fixes it by disabling NAP mode on those machines while
an SMU command is in flight.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* 'slub-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/christoph/vm:
SLUB: fix checkpatch warnings
Use non atomic unlock
SLUB: Support for performance statistics
SLUB: Alternate fast paths using cmpxchg_local
SLUB: Use unique end pointer for each slab page.
SLUB: Deal with annoying gcc warning on kfree()
The statistics provided here allow the monitoring of allocator behavior but
at the cost of some (minimal) loss of performance. Counters are placed in
SLUB's per cpu data structure. The per cpu structure may be extended by the
statistics to grow larger than one cacheline which will increase the cache
footprint of SLUB.
There is a compile option to enable/disable the inclusion of the runtime
statistics and its off by default.
The slabinfo tool is enhanced to support these statistics via two options:
-D Switches the line of information displayed for a slab from size
mode to activity mode.
-A Sorts the slabs displayed by activity. This allows the display of
the slabs most important to the performance of a certain load.
-r Report option will report detailed statistics on
Example (tbench load):
slabinfo -AD ->Shows the most active slabs
Name Objects Alloc Free %Fast
skbuff_fclone_cache 33 111953835 111953835 99 99
:0000192 2666 5283688 5281047 99 99
:0001024 849 5247230 5246389 83 83
vm_area_struct 1349 119642 118355 91 22
:0004096 15 66753 66751 98 98
:0000064 2067 25297 23383 98 78
dentry 10259 28635 18464 91 45
:0000080 11004 18950 8089 98 98
:0000096 1703 12358 10784 99 98
:0000128 762 10582 9875 94 18
:0000512 184 9807 9647 95 81
:0002048 479 9669 9195 83 65
anon_vma 777 9461 9002 99 71
kmalloc-8 6492 9981 5624 99 97
:0000768 258 7174 6931 58 15
So the skbuff_fclone_cache is of highest importance for the tbench load.
Pretty high load on the 192 sized slab. Look for the aliases
slabinfo -a | grep 000192
:0000192 <- xfs_btree_cur filp kmalloc-192 uid_cache tw_sock_TCP
request_sock_TCPv6 tw_sock_TCPv6 skbuff_head_cache xfs_ili
Likely skbuff_head_cache.
Looking into the statistics of the skbuff_fclone_cache is possible through
slabinfo skbuff_fclone_cache ->-r option implied if cache name is mentioned
.... Usual output ...
Slab Perf Counter Alloc Free %Al %Fr
--------------------------------------------------
Fastpath 111953360 111946981 99 99
Slowpath 1044 7423 0 0
Page Alloc 272 264 0 0
Add partial 25 325 0 0
Remove partial 86 264 0 0
RemoteObj/SlabFrozen 350 4832 0 0
Total 111954404 111954404
Flushes 49 Refill 0
Deactivate Full=325(92%) Empty=0(0%) ToHead=24(6%) ToTail=1(0%)
Looks good because the fastpath is overwhelmingly taken.
skbuff_head_cache:
Slab Perf Counter Alloc Free %Al %Fr
--------------------------------------------------
Fastpath 5297262 5259882 99 99
Slowpath 4477 39586 0 0
Page Alloc 937 824 0 0
Add partial 0 2515 0 0
Remove partial 1691 824 0 0
RemoteObj/SlabFrozen 2621 9684 0 0
Total 5301739 5299468
Deactivate Full=2620(100%) Empty=0(0%) ToHead=0(0%) ToTail=0(0%)
Descriptions of the output:
Total: The total number of allocation and frees that occurred for a
slab
Fastpath: The number of allocations/frees that used the fastpath.
Slowpath: Other allocations
Page Alloc: Number of calls to the page allocator as a result of slowpath
processing
Add Partial: Number of slabs added to the partial list through free or
alloc (occurs during cpuslab flushes)
Remove Partial: Number of slabs removed from the partial list as a result of
allocations retrieving a partial slab or by a free freeing
the last object of a slab.
RemoteObj/Froz: How many times were remotely freed object encountered when a
slab was about to be deactivated. Frozen: How many times was
free able to skip list processing because the slab was in use
as the cpuslab of another processor.
Flushes: Number of times the cpuslab was flushed on request
(kmem_cache_shrink, may result from races in __slab_alloc)
Refill: Number of times we were able to refill the cpuslab from
remotely freed objects for the same slab.
Deactivate: Statistics how slabs were deactivated. Shows how they were
put onto the partial list.
In general fastpath is very good. Slowpath without partial list processing is
also desirable. Any touching of partial list uses node specific locks which
may potentially cause list lock contention.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
We use a NULL pointer on freelists to signal that there are no more objects.
However the NULL pointers of all slabs match in contrast to the pointers to
the real objects which are in different ranges for different slab pages.
Change the end pointer to be a pointer to the first object and set bit 0.
Every slab will then have a different end pointer. This is necessary to ensure
that end markers can be matched to the source slab during cmpxchg_local.
Bring back the use of the mapping field by SLUB since we would otherwise have
to call a relatively expensive function page_address() in __slab_alloc(). Use
of the mapping field allows avoiding a call to page_address() in various other
functions as well.
There is no need to change the page_mapping() function since bit 0 is set on
the mapping as also for anonymous pages. page_mapping(slab_page) will
therefore still return NULL although the mapping field is overloaded.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Many I2C hwmon drivers define a driver ID but no other code references
these, meaning that they are useless. Discard them, along with a few
IDs which are defined but never used at all.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
* Drop unused defines
* Drop unused driver ID
* Remove trailing whitespace
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
* Drop trailing spaces
* Drop unused driver ID
* Drop stray backslashes in macros
* Rename new_client to client
* Drop redundant initializations to 0
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
* Drop history, it doesn't belong there
* Drop unused struct member
* Drop bogus struct member comment
* Drop unused driver ID
* Rename new_client to client
* Drop redundant initializations to 0
* Drop useless cast
* Drop trailing space
* Fix comment
* Drop duplicate comment
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
Let drivers walk the DMI table for their own needs. Some drivers need
data stored in OEM-specific DMI records for proper operation.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (48 commits)
[SCSI] aacraid: do not set valid bit in sense information
[SCSI] ses: add new Enclosure ULD
[SCSI] enclosure: add support for enclosure services
[SCSI] sr: fix test unit ready responses
[SCSI] u14-34f: fix data direction bug
[SCSI] aacraid: pci_set_dma_max_seg_size opened up for late model controllers
[SCSI] fix BUG when sum(scatterlist) > bufflen
[SCSI] arcmsr: updates (1.20.00.15)
[SCSI] advansys: make 3 functions static
[SCSI] Small cleanups for scsi_host.h
[SCSI] dc395x: fix uninitialized var warning
[SCSI] NCR53C9x: remove driver
[SCSI] remove m68k NCR53C9x based drivers
[SCSI] dec_esp: Remove driver
[SCSI] kernel-doc: fix scsi docbook
[SCSI] update my email address
[SCSI] add protocol definitions
[SCSI] sd: handle bad lba in sense information
[SCSI] qla2xxx: Update version number to 8.02.00-k8.
[SCSI] qla2xxx: Correct issue where incorrect init-fw mailbox command was used on non-NPIV capable ISPs.
...
The enclosure misc device is really just a library providing sysfs
support for physical enclosure devices and their components.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
A lot of SCSI command replies have a protocol ID field. Add
definitions for the interpretation of that from SPC-3.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
The session age mask is only 4 bits, but session->age is 32. When
it gets larger then 15 and we try to or the bits some bits get
dropped and the check for session age in iscsi_verify_itt is useless.
The ISCSI_CID_MASK related bits are also useless since cid is always
one.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Some iscsi class messages have the dev_printk prefix and some libiscsi
and iscsi_tcp messages have "iscsi" or the module name as a prefix which
is normally pretty useless when trying to figure out which session
or connection the message is attached to. This patch adds iscsi lib
and class dev_printks so all messages have a common prefix that
can be used to figure out which object printed it.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
In qla4xxx's probe it will call the iscsi session setup functions
for session that got setup on the initial start. This then makes
it easy for the iscsi class to export a helper which indicates
when those scans are done.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This just adds iscsi session scanning which works like fc rport scanning.
The future patches will hook the drivers into Mathew Wilcox's async
scanning infrastructure, so userspace does not have to special case
iscsi and so userspace does not have to make a extra special case for
hardware iscsi root scanning.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This adds a iscsi session state file which exports the session
state for both software and hardware iscsi. It also hooks libiscsi
in.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Commit ad7f71674a ("[POWERPC] Use a
sensible default for clock_getres() in the VDSO") corrected the clock
resolution reported by the VDSO clock_getres() but introduced another
problem in that older versions of gcc (gcc-4.0 and earlier) fail to
compile the new code in arch/powerpc/kernel/asm-offsets.c.
This fixes it by introducing a new MONOTONIC_RES_NSEC define in the
generic code which is equivalent to KTIME_MONOTONIC_RES but is just an
integer constant, not a ktime union.
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
