Yanmin Zhang pointed out a sequence problem when saving the psr.  David
Mosberger provided this patch (which gave up a cycle).
Signed-off-by: Tony Luck <tony.luck@intel.com>

This patch switches the srlz.i in ia64_leave_kernel() to srlz.d.  As
per architecture manual, the former is needed only to ensure that the
clearing of PSR.IC is seen by the VHPT for subsequent instruction
fetches.  However, since the remainder of the code (up to and
including the RFI instruction) is mapped by a pinned TLB entry, there
is no chance of an iTLB miss and we don't care whether or not the VHPT
sees PSR.IC cleared.  Since srlz.d is substantially cheaper than
srlz.i, this should shave off a few cycles off the interrupt path
(unverified though; I'm not setup to measure this at the moment).
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

This patch changes comments & formatting only.  There is no code
change.
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

Improvements come from eliminating srlz.i, not scheduling AR/CR-reads
too early (while there are others still pending), scheduling the
backing-store switch as well as possible, splitting the BBB bundle
into a MIB/MBB pair.

Why is it safe to eliminate the srlz.i?  Observe
that we used to clear bits ~PSR_PRESERVED_BITS in PSR.L.  Since
PSR_PRESERVED_BITS==PSR.{UP,MFL,MFH,PK,DT,PP,SP,RT,IC}, we
ended up clearing PSR.{BE,AC,I,DFL,DFH,DI,DB,SI,TB}.  However,

 PSR.BE : already is turned off in __kernel_syscall_via_epc()
 PSR.AC : don't care (kernel normally turns PSR.AC on)
 PSR.I  : already turned off by the time fsys_bubble_down gets invoked
 PSR.DFL: always 0 (kernel never turns it on)
 PSR.DFH: don't care --- kernel never touches f32-f127 on its own
	  initiative
 PSR.DI : always 0 (kernel never turns it on)
 PSR.SI : always 0 (kernel never turns it on)
 PSR.DB : don't care --- kernel never enables kernel-level breakpoints
 PSR.TB : must be 0 already; if it wasn't zero on entry to
	  __kernel_syscall_via_epc, the branch to fsys_bubble_down
	  will trigger a taken branch; the taken-trap-handler then
	  converts the syscall into a break-based system-call.

In other words: all the bits we're clearying are either 0 already or
are don't cares!  Thus, we don't have to write PSR.L at all and we
don't have to do a srlz.i either.

Good for another ~20 cycle improvement for EPC-based heavy-weight
syscalls.
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

Two other very minor changes: use "mov.i" instead of "mov" for reading
ar.pfs (for clarity; doesn't affect the code at all).  Also, predicate
the load of r14 for consistency.
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

Avoid some stalls, which is good for about 2 cycles when invoking a
light-weight handler.  When invoking a heavy-weight handler, this
helps by about 7 cycles, with most of the improvement coming from the
improved branch-prediction achieved by splitting the BBB bundle into
two MIB bundles.
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

This patch reorganizes break_fault() to optimistically assume that a
system-call is being performed from user-space (which is almost always
the case).  If it turns out that (a) we're not being called due to a
system call or (b) we're being called from within the kernel, we fixup
the no-longer-valid assumptions in non_syscall() and .break_fixup(),
respectively.

With this approach, there are 3 major phases:

 - Phase 1: Read various control & application registers, in
	    particular the current task pointer from AR.K6.
 - Phase 2: Do all memory loads (load system-call entry,
	    load current_thread_info()->flags, prefetch
	    kernel register-backing store) and switch
	    to kernel register-stack.
 - Phase 3: Call ia64_syscall_setup() and invoke
	    syscall-handler.

Good for 26-30 cycles of improvement on break-based syscall-path.
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

Reschedule code to read ar.bsp as early as possible.  To enable this,
don't bother clearing some of the registers when we're returning to
kernel stacks.  Also, instead of trying to support the pNonSys case
(which makes no sense), do a bugcheck instead (with break 0).  Finally,
remove a clear of r14 which is a left-over from the previous patch.
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

Using stf8 seemed like a clever idea at the time, but stf8 forces
the cache-line to be invalidated in the L1D (if it happens to be
there already).  This patch eliminates a guaranteed L1D cache-miss
and, by itself, is good for a 1-2 cycle improvement for heavy-weight
syscalls.
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

Why is this a good idea?  Clearing b7 to 0 is guaranteed to do us no
good and writing it with __kernel_syscall_via_epc() yields a 6 cycle
improvement _if_ the application performs another EPC-based system-
call without overwriting b7, which is not all that uncommon.  Well
worth the minimal cost of 1 bundle of code.
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

Decreases syscall overhead by approximately 6 cycles.
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

This by itself is good for a 1-2 cycle speed up.  Effect is bigger
when combined with the later patches.
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

Call pci_enable_device() before looking at IRQ and resources,
and pci_disable_device() when shutting the interface down.

The driver requires this fix or the "pci=routeirq" workaround
on 2.6.10 and later kernels.

Reported and tested by Artur Lipowski. 

From: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

size_t is zu, ssize_t is zd...
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

This is a fix to the pgtable_quicklist code.  There is a GFP_KERNEL
allocation in pgtable_quicklist_alloc(), which spews the usual warnings
if the kernel is under heavy VM pressure and the reclaim code is
invoked.  re-enable preempt before we allocate the new page.

This patch is against 2.6.12-rc2-mm2
Signed-off-by: Martin Hicks <mort@sgi.com>
Signed-off-by:  Tony Luck <tony.luckintel.com>

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

->pretcode in struct rt_sigframe is a userland pointer (and already
treated as such by code using that field). 
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

NULL noise in sbus scsi drivers got missed
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

write_reg_le32() and read_reg_le32() expect iomem pointers...
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

trivial iomem annotations + memset() replaced with memset_io() in a
place that deals with ioremapped area. 
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

This beast is pmac-only; moreover, it won't build on other
subarchitectures. 
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Convert 8250_hp300 to use serial8250_register_port() and
serial8250_unregister_port().

Tested by Kars de Jong, 4/4/2005.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>

With unlikely() there's no need for the error path to
use gotos.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>

Ensure ARM serial driver error paths are marked with the
unlikely() compiler hint.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>

Move common includes to entry-header, and file specific includes
to the relevant file.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>

Assembly macros are pointless if they're only used once.  Move
them inline.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>

PT_TRACESYS is unused, remove it.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>

SVC_MODE reflects the MODE_SVC definition in asm/ptrace.h.  Use
the asm/ptrace.h definition instead, and remove SVC_MODE.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>

Don't define our own local constants, but use those already defined
in asm/unistd.h instead.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>