Currently a simple
void foo(void) { preempt_enable(); }
produces the following code on ARM:
foo:
bic r3, sp, #8128
bic r3, r3, #63
ldr r2, [r3, #4]
ldr r1, [r3, #0]
sub r2, r2, #1
tst r1, #4
str r2, [r3, #4]
blne preempt_schedule
mov pc, lr
The problem is that the TIF_NEED_RESCHED flag is loaded _before_ the
preemption count is stored back, hence any interrupt coming within that
3 instruction window causing TIF_NEED_RESCHED to be set won't be
seen and scheduling won't happen as it should.
Nothing currently prevents gcc from performing that reordering. There
is already a barrier() before the decrement of the preemption count, but
another one is needed between this and the TIF_NEED_RESCHED flag test
for proper code ordering.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Acked-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jan's crosscompile page [1] shows, that one regression in 2.6.15-rc is
that the v850 defconfig does no longer compile.
The compile error is:
<-- snip -->
...
CC arch/v850/kernel/setup.o
In file included from /usr/src/ctest/rc/kernel/arch/v850/kernel/setup.c:17:
/usr/src/ctest/rc/kernel/include/linux/irq.h:13:43: asm/smp.h: No such file or directory
make[2]: *** [arch/v850/kernel/setup.o] Error 1
<-- snip -->
The #include <asm/smp.h> in irq.h was intruduced in 2.6.15-rc.
Since include/linux/irq.h needs code from asm/smp.h only in the
CONFIG_SMP=y case and linux/smp.h #include's asm/smp.h only in the
CONFIG_SMP=y case, I'm suggesting this patch to #include <linux/smp.h>
in irq.h.
I've tested the compilation with both CONFIG_SMP=y and CONFIG_SMP=n
on i386.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
NETDEV_UP might be sent even if the link attached to the interface was
not ready. DAD does not make sense in such case, so we won't do so.
After interface
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
This is an interim patch until changes in an updated
ACPICA core increase the limit to 255.
Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
There's currently a diagnostic printk in relay_switch_subbuf() meant as
a warning if you accidentally try to log an event larger than the
sub-buffer size.
The problem is if this happens while logging from somewhere it's not
safe to be doing printks, such as in the scheduler, you can end up with
a deadlock. This patch removes the warning from relay_switch_subbuf()
and instead prints some diagnostic info when the channel is closed.
Thanks to Mathieu Desnoyers for pointing out the problem and
suggesting a fix.
Signed-off-by: Tom Zanussi <zanussi@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Ensure we call unmap_mapping_range() and sync dirty pages to disk before
doing an NFS direct write.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When we insert a new xfrm_state which potentially
subsumes an existing one, make sure all cached
bundles are flushed so that the new SA is used
immediately.
Signed-off-by: David S. Miller <davem@davemloft.net>
I reported a problem and gave hints to the solution, but nobody seemed
to react. So I prepared a patch against 2.6.14.4.
Tested on 2.6.14.4 with "ip monitor addr" and with the program
attached, while adding and removing IPv6 address. Both programs didn't
receive any messages. Tested 2.6.14.4 + this patch, and both programs
received add and remove messages.
Signed-off-by: Kristian Slavov <kristian.slavov@nomadiclab.com>
Acked-by: Jamal Hadi salim <hadi@cyberus.ca>
ACKed-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This (and the three subsequent patches) is working well on OMAP H4 with
2.6.15-rc4 kernel and passes the LTP fs test.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
DMA_MODE_{READ,WRITE} are declared in asm-powerpc/dma.h and their
declarations there match the definitions. Old declarations in
ppc4xx_dma.h are not right anymore (wrong type, to start with).
Killed them, added include of asm/dma.h where needed.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
sparc64, i386 and x86_64 have support for a special data section dedicated
to rarely updated data that is frequently read. The section was created to
avoid false sharing of those rarely read data with frequently written kernel
data.
This patch creates such a data section for ia64 and will group rarely written
data into this section.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The logic that decides that a fork() might be able to avoid copying a VM
area when it can be re-created by page faults didn't know about the new
vm_insert_page() case.
Also make some things a bit more anal wrt VM_PFNMAP.
Pointed out by Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The udelay() inline for ia64 uses the ITC. If CONFIG_PREEMPT is enabled
and the platform has unsynchronized ITCs and the calling task migrates
to another CPU while doing the udelay loop, then the effective delay may
be too short or very, very long.
This patch disables preemption around 100 usec chunks of the overall
desired udelay time. This minimizes preemption-holdoffs.
udelay() is now too big to be inline, move it out of line and export it.
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
In the scenario that a link was broken, the devloss timer for each
rport was expire at roughly the same time, causing lots of "delete"
workqueue items being queued. Depth is dependent upon the number of
rports that were on the link.
The rport target remove calls were calling flush_scheduled_work(),
which would interrupt the stream, and start the next workqueue item,
which did the same thing, and so on until recursion depth was large.
This fix stops the recursion in the initial delete path, and pushes it
off to a host-level work item that reaps the dead rports.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Rename scsi_print_msg to spi_print_msg and move its prototype from
scsi_dbg.h to scsi_transport_spi.h
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This merge is pretty extensive. The conflict is over the new
req->retries parameter, so I had to change the prototype to
scsi_setup_blk_pc_cmnd() and the usage in sd, sr and st.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
- export __blk_put_request and blk_execute_rq_nowait
needed for async REQ_BLOCK_PC requests
- seperate max_hw_sectors and max_sectors for block/scsi_ioctl.c and
SG_IO bio.c helpers per Jens's last comments. Since block/scsi_ioctl.c SG_IO was
already testing against max_sectors and SCSI-ml was setting max_sectors and
max_hw_sectors to the same value this does not change any scsi SG_IO behavior. It only
prepares ll_rw_blk.c, scsi_ioctl.c and bio.c for when SCSI-ml begins to set
a valid max_hw_sectors for all LLDs. Today if a LLD does not set it
SCSI-ml sets it to a safe default and some LLDs set it to a artificial low
value to overcome memory and feedback issues.
Note: Since we now cap max_sectors to BLK_DEF_MAX_SECTORS, which is 1024,
drivers that used to call blk_queue_max_sectors with a large value of
max_sectors will now see the fs requests capped to BLK_DEF_MAX_SECTORS.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
