Add syscall slow path hooks to notify syscall entry
and exit on CPUs that want to support userspace RCU
extended quiescent state.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Alessio Igor Bogani <abogani@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Clear the syscalls hook of a task when it's scheduled out so that if
the task migrates, it doesn't run the syscall slow path on a CPU
that might not need it.
Also set the syscalls hook on the next task if needed.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Alessio Igor Bogani <abogani@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
By default we don't want to enter into RCU extended quiescent
state while in userspace because doing this produces some overhead
(eg: use of syscall slowpath). Set it off by default and ready to
run when some feature like adaptive tickless need it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Alessio Igor Bogani <abogani@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Allow calls to rcu_user_enter() even if we are already
in userspace (as seen by RCU) and allow calls to rcu_user_exit()
even if we are already in the kernel.
This makes the APIs more flexible to be called from architectures.
Exception entries for example won't need to know if they come from
userspace before calling rcu_user_exit().
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Alessio Igor Bogani <abogani@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
We can have either shared kernel or jump label support, but not both.
If a kernel gets IPL'ed from an NSS it's not possible to patch the
text segment, since it's read-only.
Therefore any static branches cannot be updated. So we need to make
sure that shared kernel support is disabled if jump label support
is enabled.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add support for new BPF_S_ANC_ALU_XOR_X instruction which got added
with ffe06c17 "filter: add XOR operation".
s390 version of 4bfaddf1 "x86 bpf_jit: support BPF_S_ANC_ALU_XOR_X instruction".
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Same as 0fa0e2f0 "x86: Move call to print_modules() out of show_regs()".
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Same as 0d26d1d8 "x86/mm: Mark free_initrd_mem() as __init".
In addition also add the __init annotation to setup_zero_pages().
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
A common way to prepare a z/VM mini disk is to format the real device
with a z/VM tool like CPFMTXA and then define a mini disk that excludes
the first cylinder, i.e. the cylinder 0 of the virtual disk is located
at cylinder 1 of the real device.
The DASD device driver will recognize such a mini disk as formatted, as
the uniform record layout on the disk matches that of an LDL formatted
device. However, the cylinder value in the 'count' field of the ECKD
records matches the geometry of the real device, and not that of the
mini disk, so I/O requests will fail with 'record not found' errors.
To make the mini disk usable, it needs to be formatted with a tool like
dasdfmt. To enable tools like distribution installation tools to
recognize this situation, the DASD device driver should report such a
mini disk as 'not formatted'.
To this end we need to extend the device recognition code to check not
just for proper record sizes, but also for proper cylinder/head/record
values.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Reviewed-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Convert a nonnegative error return code to a negative one, as returned
elsewhere in the function.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
{ ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
when != &ret
*if(...)
{
... when != ret = e2
when forall
return ret;
}
// </smpl>
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The generic variant has a local_irq_save/restore pair which is quite
expensive. It is sufficient to disable preemption, which is a no-op
with !CONFIG_PREEMPT and then use the regular xchg macro.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since "Kconfig: split the s390 base menu" CONFIG_KEXEC gets always selected.
Therefore there is no point in keeping CONFIG_KEXEC anywhere.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use designated initializers for the irq class array in irq.c so
it's always guaranteed that the order of elements is equal to
their corresponding parts in irq.h.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Get rid of these:
arch/s390/kernel/smp.c:134:19: warning: ‘status’ may be used uninitialized in this function [-Wuninitialized]
arch/s390/mm/pgtable.c:641:10: warning: ‘table’ may be used uninitialized in this function [-Wuninitialized]
arch/s390/mm/pgtable.c:644:12: warning: ‘page’ may be used uninitialized in this function [-Wuninitialized]
drivers/s390/cio/cio.c:1037:14: warning: ‘schid’ may be used uninitialized in this function [-Wuninitialized]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Move fill_cpu_elf_notes() prototype to header file.
This way we get compile errors if e.g. the number of function
parameters get changed.
Otherwise it's possible to change just the definition and everything
else still compiles fine, but the result is broken code.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add appropriate header file:
arch/s390/kernel/process.c:327:15: warning: symbol 'arch_align_stack' was not declared.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
if (MACHINE_HAS_TE) translates to if (0) on !CONFIG_64BIT however the
compiler still warns about invalid shifts within non-reachable code.
So add an explicit ifdef to get rid of this warning:
arch/s390/kernel/ptrace.c: In function ‘update_per_regs’:
arch/s390/kernel/ptrace.c:63:4: warning: left shift count >= width of type [enabled by default]
arch/s390/kernel/ptrace.c:65:4: warning: left shift count >= width of type [enabled by default]
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The early kernel decrompressing code can't call into the kernel
in order to profile branches. Fixes this link error:
arch/s390/boot/compressed/misc.o: In function `decompress_kernel':
misc.c:(.text+0x9a6): undefined reference to `ftrace_likely_update'
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The whole hardware support is only available in zArch mode.
Fixes also this compile warning:
arch/s390/kernel/perf_cpum_cf.c: In function ‘cpumf_pmu_init’:
arch/s390/kernel/perf_cpum_cf.c:670:2: warning: left shift count >= width of type [enabled by default]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix this compile error:
In file included from drivers/s390/char/tape_core.c:29:0:
drivers/s390/char/tape_std.h:103:66: warning: ‘struct request’ declared inside parameter list [enabled by default]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Get rid of this compile warning for CONFIG_32BIT:
drivers/s390/crypto/ap_bus.c:168:12: warning: ‘ap_configuration_available’
defined but not used [-Wunused-function]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use for_each_set_bit() to simplify the code.
spatch with a semantic match is used to found this.
(http://coccinelle.lip6.fr/)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Calling debug_event the s390 debug feature only logs up to buf_size
bytes of the debug view. If debug_event is called with more bytes
than buf_size the additional data is ignored and not logged in the
debug view.
Use multiple calls to debug_event if the length exceeds buf_size.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Detect external AP bus configuration changes and request
an AP device rescan.
Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Changing the return value of vmlogrdr_open() to -EOPNOTSUPP if O_NONBLOCK
is specified shouldn't have any negative side effects.
Any existing user wouldn't specify that flag since it wouldn't work anyway.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Change return value of appldata_asm() to -EOPNOTSUPP in case of an
error. The return value was only used internally and not passed to
user space.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Returning -ENOSYS on kexec_load() is a bad idea since user space cannot
tell if the system call is not implmented or if it failed.
Use -EOPNOTSUPP in case somebody tries a kexec_load on a NSS image based
kernel instead.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Change -ENOSYS to -EOPNOTSUPP. Return value is used only internally.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The return value was only internally used, so it's ok to change.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
For non-existent ioctls -ENOTTY should be returned.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Change return code handling of the stsi() function:
In case function code 0 was specified the return value is the
current configuration level (already shifted). That way all
the code that actually copied the stsi_0() function can go
away.
Otherwise the return value is 0 (success) or negative to
indicate an error (currently only -EOPNOTSUPP).
Also stsi() is no longer an inline function. The function is
not performance critical, but every caller would generate an
exception table entry for this function.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
I was checking why this spinlock was never initialized, but it turns
out it's not used anywhere, so we can drop it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This is the s390 port of 70627654 "x86, extable: Switch to relative
exception table entries".
Reduces the size of our exception tables by 50% on 64 bit builds.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Do not reset drvdata before the block device is cleaned up. With a
non-empty block queue drvdata could be accessed.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the spinlock from struct scm_device. drvdata and attributes
are guarded via device_lock.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The cpu polarization member is the only per cpu state that is not part
of the pcpu structure. So add it there and have everything in one place.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The maximum nesting of the cpu topology is evaluated when /proc/sysinfo
is the first time read. This happens without a lock and a concurrent
reader on a different cpu can see and use an invalid intermediate value.
Besides the fact that this race is quite unlikely the worst thing that
could happen is that /proc/sysinfo would contain bogus information about
the machine's cpu topology.
Nevertheless this should be fixed. So move the detection code to the
early machine detection code and since now the value is early available
use it in the topology code as well.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch introduces the __get_user_pages_fast() function on s390,
which will be needed with CONFIG_TRANSPARENT_HUGEPAGE and futex.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add a couple of missing fields that were introduced with z196.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The current proc implementation of the /proc/sysinfo file writes all
informations contained in all system information blocks to a single
page.
This is done by calling sprintf all the time in the expectation that
everything will fit into a single page. This however is not necessarily
true if the configuration of a machine is very large.
So convert /proc/sysinfo to avoid writing into random memory regions.
For readability reasons a couple of lines are longer than 80 characters.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Any change to sysinfo.h causes a whole kernel recompile since sysinfo.h is
included by topology.h, which again is used nearly everywhere.
So remove that include and add a forward declaration instead.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Shorten the code for addressing mode initialization. Also add missing
__init annotations, since this code is only used during kernel initialization.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Renaming the globally visible variable "user_mode" to "addressing_mode" in
order to fix a name clash was not a good idea. (Commit 37fe1d73 "s390/mm:
rename user_mode variable to addressing_mode")
Looking at the code after a couple of weeks one thinks: addressing mode of
what?
So rename the variable again. This time to s390_user_mode. Which hopefully
makes more sense.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In some usage scenarios it is desireable to work with disk images or
virtualized DASD devices. One problem that prevents such applications
is the partition detection in ibm.c. Currently it works only for
devices that support the BIODASDINFO2 ioctl, in other words, it only
works for devices that belong to the DASD device driver.
The information gained from the BIODASDINFO2 ioctl is only for a small
set of legacy cases abolutely necessary. All current VOL1, LNX1 and
CMS1 type of disk labels can be interpreted correctly without this
information, as long as the generic HDIO_GETGEO ioctl works and
provides a correct disk geometry.
This patch makes the ibm.c partition detection as independent as
possible from the BIODASDINFO2 ioctl. Only the following two cases are
still restricted to real DASDs:
- An FBA DASD, or LDL formatted ECKD DASD without any disk label.
- An old style LNX1 label (without large volume support) on a disk
with inconsistent device geometry.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Change the default addressing mode so that user space runs in primary space
and the kernel runs in home space.
In addition remove the "switch_amode" kernel parameter so all users who
already specified they want the new default behaviour will stay in the
"switched" mode instead of in the opposite they intended.
If there is a need to switch addressing modes, this can be done with the
"user_mode" kernel parameter: user_mode=home
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
