linux-toradex.git/arch/powerpc/sysdev/xive/native.c, branch v4.14

treewide: make "nr_cpu_ids" unsigned

2017-09-09T01:26:48+00:00

First, number of CPUs can't be negative number.

Second, different signnnedness leads to suboptimal code in the following
cases:

1)
	kmalloc(nr_cpu_ids * sizeof(X));

"int" has to be sign extended to size_t.

2)
	while (loff_t *pos < nr_cpu_ids)

MOVSXD is 1 byte longed than the same MOV.

Other cases exist as well. Basically compiler is told that nr_cpu_ids
can't be negative which can't be deduced if it is "int".

Code savings on allyesconfig kernel: -3KB

	add/remove: 0/0 grow/shrink: 25/264 up/down: 261/-3631 (-3370)
	function                                     old     new   delta
	coretemp_cpu_online                          450     512     +62
	rcu_init_one                                1234    1272     +38
	pci_device_probe                             374     399     +25

				...

	pgdat_reclaimable_pages                      628     556     -72
	select_fallback_rq                           446     369     -77
	task_numa_find_cpu                          1923    1807    -116

Link: http://lkml.kernel.org/r/20170819114959.GA30580@avx2
Signed-off-by: Alexey Dobriyan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

powerpc/xive: add the HW IRQ number under xive_irq_data

2017-09-02T11:02:37+00:00

It will be required later by the H_INT_ESB hcall.

Signed-off-by: Cédric Le Goater 
Acked-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman

powerpc/xive: introduce a common routine xive_queue_page_alloc()

2017-09-02T11:02:34+00:00

This routine will be used in the spapr backend. Also introduce a short
xive_alloc_order() helper.

Signed-off-by: Cédric Le Goater 
Reviewed-by: David Gibson 
Acked-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman

powerpc: Convert to using %pOF instead of full_name

2017-08-23T12:27:04+00:00

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: Anatolij Gustschin 
Cc: Scott Wood 
Cc: Kumar Gala 
Cc: Arnd Bergmann 
Cc: linuxppc-dev@lists.ozlabs.org
Reviewed-by: Tyrel Datwyler 
Signed-off-by: Michael Ellerman

powerpc/xive: Fix section mismatch warnings

2017-08-10T13:41:02+00:00

Both xive_core_init() and xive_native_init() are called from and call
__init routines, so they should also be __init.

Signed-off-by: Michael Ellerman

powerpc/xive: Silence message about VP block allocation

2017-06-28T03:08:08+00:00

There is no reason for that message to be pr_info(), it will be printed
every time we start a KVM guest.

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman

Merge branch 'kvm-ppc-next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD

2017-05-09T09:50:01+00:00

The main thing here is a new implementation of the in-kernel
XICS interrupt controller emulation for POWER9 machines, from Ben
Herrenschmidt.

POWER9 has a new interrupt controller called XIVE (eXternal Interrupt
Virtualization Engine) which is able to deliver interrupts directly
to guest virtual CPUs in hardware without hypervisor intervention.
With this new code, the guest still sees the old XICS interface but
performance is better because the XICS emulation in the host uses the
XIVE directly rather than going through a XICS emulation in firmware.

Conflicts:
	arch/powerpc/kernel/cpu_setup_power.S [cherry-picked fix]
	arch/powerpc/kvm/book3s_xive.c [include asm/debugfs.h]

KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller

2017-04-27T11:37:29+00:00

This patch makes KVM capable of using the XIVE interrupt controller
to provide the standard PAPR "XICS" style hypercalls. It is necessary
for proper operations when the host uses XIVE natively.

This has been lightly tested on an actual system, including PCI
pass-through with a TG3 device.

Signed-off-by: Benjamin Herrenschmidt 
[mpe: Cleanup pr_xxx(), unsplit pr_xxx() strings, etc., fix build
 failures by adding KVM_XIVE which depends on KVM_XICS and XIVE, and
 adding empty stubs for the kvm_xive_xxx() routines, fixup subject,
 integrate fixes from Paul for building PR=y HV=n]
Signed-off-by: Michael Ellerman

powerpc/xive: Fix missing check of rc != OPAL_BUSY

2017-04-20T04:43:19+00:00

Dan Carpenter noticed that the code in __xive_native_disable_queue() has a for
loop with an unconditional break in the middle, which doesn't make a lot of
sense.

What the code's supposed to do is loop as long as OPAL says it's busy, if we get
any other return code, either success or failure, then we should break the loop.

So add the missing check.

Fixes: 243e25112d06 ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Reported-by: Dan Carpenter 
Signed-off-by: Michael Ellerman

powerpc/xive: Native exploitation of the XIVE interrupt controller

2017-04-10T11:41:34+00:00

The XIVE interrupt controller is the new interrupt controller
found in POWER9. It supports advanced virtualization capabilities
among other things.

Currently we use a set of firmware calls that simulate the old
"XICS" interrupt controller but this is fairly inefficient.

This adds the framework for using XIVE along with a native
backend which OPAL for configuration. Later, a backend allowing
the use in a KVM or PowerVM guest will also be provided.

This disables some fast path for interrupts in KVM when XIVE is
enabled as these rely on the firmware emulation code which is no
longer available when the XIVE is used natively by Linux.

A latter patch will make KVM also directly exploit the XIVE, thus
recovering the lost performance (and more).

Signed-off-by: Benjamin Herrenschmidt 
[mpe: Fixup pr_xxx("XIVE:"...), don't split pr_xxx() strings,
 tweak Kconfig so XIVE_NATIVE selects XIVE and depends on POWERNV,
 fix build errors when SMP=n, fold in fixes from Ben:
   Don't call cpu_online() on an invalid CPU number
   Fix irq target selection returning out of bounds cpu#
   Extra sanity checks on cpu numbers
 ]
Signed-off-by: Michael Ellerman