The current tile rt_sigreturn() syscall pattern uses the common idiom
of loading up pt_regs with all the saved registers from the time of
the signal, then anticipating the fact that we will clobber the ABI
"return value" register (r0) as we return from the syscall by setting
the rt_sigreturn return value to whatever random value was in the pt_regs
for r0.
However, this breaks in our 64-bit kernel when running "compat" tasks,
since we always sign-extend the "return value" register to properly
handle returned pointers that are in the upper 2GB of the 32-bit compat
address space. Doing this to the sigreturn path then causes occasional
random corruption of the 64-bit r0 register.
Instead, we stop doing the crazy "load the return-value register"
hack in sigreturn. We already have some sigreturn-specific assembly
code that we use to pass the pt_regs pointer to C code. We extend that
code to also set the link register to point to a spot a few instructions
after the usual syscall return address so we don't clobber the saved r0.
Now it no longer matters what the rt_sigreturn syscall returns, and the
pt_regs structure can be cleanly and completely reloaded.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Previously we were just setting up the "tp" register in the
new task as started by clone() in libc. However, this is not
quite right, since in principle a signal might be delivered to
the new task before it had its TLS set up. (Of course, this race
window still exists for resetting the libc getpid() cached value
in the new task, in principle. But in any case, we are now doing
this exactly the way all other architectures do it.)
This change is important for 2.6.37 since the tile glibc we will
be submitting upstream will not set TLS in user space any more,
so it will only work on a kernel that has this fix. It should
also be taken for 2.6.36.x in the stable tree if possible.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: stable <stable@kernel.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
arch/tile: fix memchr() not to dereference memory for zero length
arch/tile: make glibc's sysconf(_SC_NPROCESSORS_CONF) work correctly
arch/tile: fix rwlock so would-be write lockers don't block new readers
* 'drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
pci root complex: support for tile architecture
drivers/net/tile/: on-chip network drivers for the tile architecture
MAINTAINERS: add drivers/char/hvc_tile.c as maintained by tile
glibc assumes that it can count /sys/devices/system/cpu/cpu* to get
the number of configured cpus. For this to be valid on tile, we need
to generate a "cpu" entry for all cpus, including the ones that are
not currently allocated for Linux's use.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change enables PCI root complex support for TILEPro. Unlike
TILE-Gx, TILEPro has no support for memory-mapped I/O, so the PCI
support consists of hypervisor upcalls for PIO, DMA, etc. However,
the performance is fine for the devices we have tested with so far
(1Gb Ethernet, SATA, etc.).
The <asm/io.h> header was tweaked to be a little bit more aggressive
about disabling attempts to map/unmap IO port space. The hacky
<asm/pci-bridge.h> header was rolled into the <asm/pci.h> header
and the result was simplified. Both of the latter two headers were
preliminary versions not meant for release before now - oh well.
There is one quirk for our TILEmpower platform, which accidentally
negotiates up to 5GT and needs to be kicked down to 2.5GT.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The big kernel lock has been removed from all these files at some point,
leaving only the #include.
Remove this too as a cleanup.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Arnd's recent patch series tagged this device with noop_llseek,
conservatively. In fact, it should be no_llseek, which we arrange
for by opening the device with nonseekable_open().
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The existing asm-generic/stat.h specifies st_mtime, etc., as a 32-value,
and works well for 32-bit architectures (currently microblaze, score,
and 32-bit tile). However, for 64-bit architectures it isn't sufficient
to return 32 bits of time_t; this isn't good insurance against the 2037
rollover. (It also makes glibc support less convenient, since we can't
use glibc's handy STAT_IS_KERNEL_STAT mode.)
This change extends the two "timespec" fields for each of the three atime,
mtime, and ctime fields from "int" to "long". As a result, on 32-bit
platforms nothing changes, and 64-bit platforms will now work as expected.
The only wrinkle is 32-bit userspace under 64-bit kernels taking advantage
of COMPAT mode. For these, we leave the "struct stat64" definitions with
the "int" versions of the time_t and nsec fields, so that architectures
can implement compat_sys_stat64() and friends with sys_stat64(), etc.,
and get the expected 32-bit structure layout. This requires a
field-by-field copy in the kernel, implemented by the code guarded
under __ARCH_WANT_STAT64.
This does mean that the shape of the "struct stat" and "struct stat64"
structures is different on a 64-bit kernel, but only one of the two
structures should ever be used by any given process: "struct stat"
is meant for 64-bit userspace only, and "struct stat64" for 32-bit
userspace only. (On a 32-bit kernel the two structures continue to have
the same shape, since "long" is 32 bits.)
The alternative is keeping the two structures the same shape on 64-bit
kernels, which means a 64-bit time_t in "struct stat64" for 32-bit
processes. This is a little unnatural since 32-bit userspace can't
do anything with 64 bits of time_t information, since time_t is just
"long", not "int64_t"; and in any case 32-bit userspace might expect
to be running under a 32-bit kernel, which can't provide the high 32
bits anyway. In the case of a 32-bit kernel we'd then be extending the
kernel's 32-bit time_t to 64 bits, then truncating it back to 32 bits
again in userspace, for no particular reason. And, as mentioned above,
if we have 64-bit time_t for 32-bit processes we can't easily use glibc's
STAT_IS_KERNEL_STAT, since glibc's stat structure requires an embedded
"struct timespec", which is a pair of "long" (32-bit) values in a 32-bit
userspace. "Inventive" solutions are possible, but are pretty hacky.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
The kernel was allowing any component of the pt_regs to be updated either
by signal handlers writing to the stack, or by processes writing via
PTRACE_POKEUSR or PTRACE_SETREGS, which meant they could set their PL
up from 0 to 1 and get access to kernel code and data (or, in practice,
cause a kernel panic). We now always reset the ex1 field, allowing the
user to set their ICS bit only.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change is modelled on similar fixes for other architectures.
The pt_regs "faultnum" member is set to the trap (fault) number that
caused us to enter the kernel, and is INT_SWINT_1 for the syscall software
interrupt. We already supported a pseudo value, INT_SWINT_1_SIGRETURN,
that we used for the rt_sigreturn syscall; it avoided the case where
one signal was handled, then we "tail-called" to another handler.
This change avoids the similar case where we start to call one handler,
then are preempted into another handler when we start trying to run
the first handler. We clear ->faultnum after calling handle_signal(),
and to be paranoid also in the case where there was no signal to deliver.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This completes the tile migration to the new naming scheme for
the architecture-specific irq management code.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change makes KM_TYPE_NR independent of the actual deprecated
list of km_type values, which are no longer used in tile code anywhere.
For now we leave it set to 8, allowing that many nested mappings,
and thus reserving 32MB of address space.
A few remaining places using KM_* values were cleaned up as well.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Remove checking @addr less than 0 because @addr is now unsigned.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix up the arguments to arch_ptrace() to take account of the fact that
@addr and @data are now unsigned long rather than long as of a preceding
patch in this series.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
arch/tile: convert a BUG_ON to BUILD_BUG_ON
arch/tile: make ptrace() work properly for TILE-Gx COMPAT mode
arch/tile: support new info op generated by compiler
arch/tile: minor whitespace/naming changes for string support files
arch/tile: enable single-step support for TILE-Gx
arch/tile: parameterize system PLs to support KVM port
arch/tile: add Tilera's <arch/sim.h> header as an open-source header
arch/tile: Bomb C99 comments to C89 comments in tile's <arch/sim_def.h>
arch/tile: prevent corrupt top frame from causing backtracer runaway
arch/tile: various top-level Makefile cleanups
arch/tile: change lower bound on syscall error return to -4095
arch/tile: properly export __mb_incoherent for modules
arch/tile: provide a definition of MAP_STACK
kmemleak: add TILE to the list of supported architectures.
char: hvc: check for error case
arch/tile: Add a warning if we try to allocate too much vmalloc memory.
arch/tile: update some comments to clarify register usage.
arch/tile: use better "punctuation" for VMSPLIT_3_5G and friends
arch/tile: Use <asm-generic/syscalls.h>
tile: replace some BUG_ON checks with BUILD_BUG_ON checks
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
vfs: make no_llseek the default
vfs: don't use BKL in default_llseek
llseek: automatically add .llseek fop
libfs: use generic_file_llseek for simple_attr
mac80211: disallow seeks in minstrel debug code
lirc: make chardev nonseekable
viotape: use noop_llseek
raw: use explicit llseek file operations
ibmasmfs: use generic_file_llseek
spufs: use llseek in all file operations
arm/omap: use generic_file_llseek in iommu_debug
lkdtm: use generic_file_llseek in debugfs
net/wireless: use generic_file_llseek in debugfs
drm: use noop_llseek
Previously, we tried to pass 64-bit arguments through the
"COMPAT" mode 32-bit syscall API, which turned out not to work
well. Now we just use straight 32-bit arguments in COMPAT mode,
thus requiring individual registers to be read/written with
two syscalls. Of course this is uncommon, since usually all
the registers are read or written at once.
The restructuring applies to all the tile platforms, but is
plausibly better than the original code in any case.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This is not quite the complete support, since we're not yet shipping
intvec_64.S, but it is the support relevant to the set of files we are
currently shipping, and makes it easier to track changes between
our internal sources and our public GIT repository.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
While not a port to KVM (yet), this change modifies the kernel
to be able to build either at PL1 or at PL2 with a suitable
config switch. Pushing up this change avoids handling branch
merge issues going forward with the KVM work.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change adds one of the Tilera standard <arch> headers to the set
of headers shipped with Linux. The <arch/sim.h> header provides
methods for programmatically interacting with the Tilera simulator.
The current <arch/sim.h> provides inline assembly for the _sim_syscall
function, so the declaration and definition previously provided
manually in Linux are no longer needed. We now use the standard
sim_validate_lines_evicted() method from <arch/sim.h> rather than
rolling our own direct call to sim_syscall().
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.
The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.
New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.
The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.
Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.
Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.
===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}
@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}
@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};
@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};
@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};
@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};
@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};
// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};
@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};
// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};
// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};
// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};
@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};
// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////
@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};
@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};
@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};
@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
The backtracer will normally cut itself off after 100 frames anyway,
but it's messy. With this change we notice that the frame being
reported is the same as the last one, and cut off the dump with a
message similar to what gdb displays in the same circumstance.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Previously we were using -1023, which is fine for normal syscall
error returns, but the common value in use for other platforms
is -4095, and one Tilera-specific driver does use values in the
-1100 range, so tickled this bug.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
With this change we now include <asm-generic/syscalls.h> into the "tile"
version of the header. To take full advantage of the prototypes there,
we also change our naming convention for "struct pt_regs *" syscalls so
that, e.g., _sys_execve() is the "true" syscall entry, which sets the
appropriate register to point to the pt_regs before calling sys_execve().
While doing this I realized I no longer needed the fork and vfork
entry point stubs, since those functions aren't in the generic
syscall ABI, so I removed them as well.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This "bpt_code" instruction was killed off in our development line a while
ago (the actual definition of bpt_code that is used is in kernel/traps.c)
but I didn't push it for 2.6.36 because it seemed harmless and I didn't
want to try to push more than absolutely necessary.
However, we recently fixed a bug in our gcc that had been causing
"-gdwarf2" not to be passed to the assembler, and passing this flag causes
an erroneous assembler failure in the presence of code in a data section,
sometimes. While we'd like to track down the bug in the assembler,
we'd also like to make sure 2.6.36 builds with the current toolchain,
so I'm removing this dead code as well.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
3 years transition phase is enough. Cleanup the last users and remove
the cruft.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Leo Chen <leochen@broadcom.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Chris Zankel <chris@zankel.net>
This cut-and-paste bug was caused by rewriting the register dump
code to use only a single printk per line of output.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
During context switch, save and restore a couple of additional bits of
tilegx user state that can be persistently modified by userspace.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Rather than just using pt_regs, it now contains the actual saved
state explicitly, similar to pt_regs. By doing it this way, we
provide a cleaner API for userspace (or equivalently, we avoid the
need for libc to provide its own definition of sigcontext).
While we're at it, move PT_FLAGS_xxx to where they are not visible
from userspace. And always pass siginfo and mcontext to signal
handlers, even if they claim they don't need it, since sometimes
they actually try to use it anyway in practice.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The sys_execve() implementation was properly const-ified but not
the declaration, the syscall wrappers, or the compat version.
This change completes the constification process.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Make do_execve() take a const filename pointer so that kernel_execve() compiles
correctly on ARM:
arch/arm/kernel/sys_arm.c:88: warning: passing argument 1 of 'do_execve' discards qualifiers from pointer target type
This also requires the argv and envp arguments to be consted twice, once for
the pointer array and once for the strings the array points to. This is
because do_execve() passes a pointer to the filename (now const) to
copy_strings_kernel(). A simpler alternative would be to cast the filename
pointer in do_execve() when it's passed to copy_strings_kernel().
do_execve() may not change any of the strings it is passed as part of the argv
or envp lists as they are some of them in .rodata, so marking these strings as
const should be fine.
Further kernel_execve() and sys_execve() need to be changed to match.
This has been test built on x86_64, frv, arm and mips.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Until now, the tile architecture ABI for syscall return has just been
that r0 holds the return value, and an error is only signalled like it is
for kernel code, with a negative small number.
However, this means that in multiple places in userspace we end up writing
the same three-cycle idiom that tests for a small negative number for
error. It seems cleaner to instead move that code into the kernel, and
set r1 to hold zero on success or errno on failure; previously, r1 was
just zeroed on return from the kernel (to avoid leaking kernel state).
This way a single conditional branch after the syscall is sufficient
to test for the failure case. The number of cycles taken is the same,
but the error-checking code is in just one place, so total code size is
smaller, and random userspace syscall code is easier to understand.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This functionality was stubbed out until recently. Now we support our
normal backtracing API on TILE-Gx as well as on TILE64/TILEPro.
This change includes a tweak to the instruction encoding caused by
adding addxli for compat mode.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
First, the siginfo preamble wasn't quite right; we need to indicate
that we are padding up to 4 ints of preamble for 64-bit code, and
then for compat mode we need to pad differently, using only 3 ints.
Second, the C ABI requires a save area of two registers, not two
pointers, since in compat mode we have 64-bit registers all of which
we need to save, even though we only have 32-bit VAs.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
We were using the same 5-sec minsec for the clocksource and sched_clock
that we were using for the clock_event_device. For the clock_event_device
that's exactly right since it has a short maximum countdown time.
But for sched_clock we want to avoid wraparound when converting from
ticks to nsec over a much longer window, so we force a shift of 10.
And for clocksource it seems dodgy to use a 5-sec minsec as well, so we
copy some other platforms and force a shift of 22.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This commit is primarily changes caused by reviewing "sparse"
and "checkpatch" output on our sources, so is somewhat noisy, since
things like "printk() -> pr_err()" (or whatever) throughout the
codebase tend to get tedious to read. Rather than trying to tease
apart precisely which things changed due to which type of code
review, this commit includes various cleanups in the code:
- sparse: Add declarations in headers for globals.
- sparse: Fix __user annotations.
- sparse: Using gfp_t consistently instead of int.
- sparse: removing functions not actually used.
- checkpatch: Clean up printk() warnings by using pr_info(), etc.;
also avoid partial-line printks except in bootup code.
- checkpatch: Use exposed structs rather than typedefs.
- checkpatch: Change some C99 comments to C89 comments.
In addition, a couple of minor other changes are rolled in
to this commit:
- Add support for a "raise" instruction to cause SIGFPE, etc., to be raised.
- Remove some compat code that is unnecessary when we fully eliminate
some of the deprecated syscalls from the generic syscall ABI.
- Update the tile_defconfig to reflect current config contents.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
The C file (tile-desc_{32,64}.c) was about 300KB before this change,
and is now shrunk down to 100K. The original file included support
for BFD in the binutils toolchain, which is not necessary in the
kernel; the kernel version only needs to include enough support to
enable the single-stepper and backtracer.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
This network (the "UDN") connects all the cpus on the chip in a
wormhole-routed dynamic network. Subrectangles of the chip can
be allocated by a "create" ioctl on /dev/hardwall, and then to access the
UDN in that rectangle, tasks must perform an "activate" ioctl on that
same file object after affinitizing themselves to a single cpu in
the region. Sending a wormhole-routed message that tries to leave
that subrectangle causes all activated tasks to receive a SIGILL
(just as they would if they tried to access the UDN without first
activating themselves to a hardwall rectangle).
The original submission of this code to LKML had the driver
instantiated under /proc/tile/hardwall. Now we just use a character
device for this, conventionally /dev/hardwall. Some futures planning
for the TILE-Gx chip suggests that we may want to have other types of
devices that share the general model of "bind a task to a cpu, then
'activate' a file descriptor on a pseudo-device that gives access to
some hardware resource". As such, we are using a device rather
than, for example, a syscall, to set up and activate this code.
As part of this change, the compat_ptr() declaration was fixed and used
to pass the compat_ioctl argument to the normal ioctl. So far we limit
compat code to 2GB, so the difference between zero-extend and sign-extend
(the latter being correct, eventually) had been overlooked.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
This model is based on the on-chip interrupt model used by the
TILE-Gx next-generation hardware, and interacts much more cleanly
with the Linux generic IRQ layer.
The change includes modifications to the Tilera hypervisor, which
are reflected in the hypervisor headers in arch/tile/include/arch/.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Chris Metcalf