When a CPU is offlined, we leave the timer interrupts disabled
because fixup_irqs() does not explicitly take care of that case.
Fix this by invoking tick_ops->disable_irq().
Based upon analysis done by Paul E. McKenney.
Signed-off-by: David S. Miller <davem@davemloft.net>
Make sparc64 refrain from clearing a given to-be-offlined CPU's bit in the
cpu_online_mask until it has processed pending irqs. This change
prevents other CPUs from being blindsided by an apparently offline CPU
nevertheless changing globally visible state.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When I switched sparc64 over to the generic helpers for
smp_call_function(), I didn't convert the dinky call_lock
we had.
Use ipi_call_lock() and ipi_call_unlock().
Signed-off-by: David S. Miller <davem@davemloft.net>
When a device is under an EBUS or ISA bus, the resource flags
don't get set properly.
Fix this by re-evaluating the resource flags at each level of
bus as we apply ranges on the way to the root. And let PCI
override any existing flags setting, but don't let the
default flags calculator make such overrides.
Signed-off-by: David S. Miller <davem@davemloft.net>
First, lmb_enforce_memory_limit() interprets it's argument
(mostly, heh) as a size limit not an address limit. So pass
the raw cmdline_memory_size value into it. And we don't
need to check it against zero, lmb_enforce_memory_limit() does
that for us.
Next, free_initmem() needs special handling when the kernel
command line trims the available memory. The problem case is
if the trimmed out memory is where the kernel image itself
resides.
When that memory is trimmed out, we don't add those physical
ram areas to the sparsemem active ranges, amongst other things.
Which means that this free_initmem() code will free up invalid
page structs, resulting in either crashes or hangs.
Just quick fix this by not freeing initmem at all if "mem="
was given on the boot command line.
Signed-off-by: David S. Miller <davem@davemloft.net>
Things like lockdep can try to do stack backtraces before
the irqstack blocks have been setup. So don't try to match
their ranges so early on.
Also, remove unused variable in save_stack_trace().
Signed-off-by: David S. Miller <davem@davemloft.net>
The calls down into prom_printf() when we detect an overflowed stack
can recurse again since the overflow stack will be "below" the current
kernel stack limit.
Prevent this by just returning straight if we are on the stack
overflow safe stack already.
Signed-off-by: David S. Miller <davem@davemloft.net>
Based upon a report and initial patch by Friedrich Oslage.
The intention is to provide this facility for
__trigger_all_cpu_backtrace even if MAGIC_SYSRQ is not set.
The only part that should have MAGIC_SYSRQ ifdef protection is the
sparc_globalreg_op sysrq regitration and immediate code.
Signed-off-by: David S. Miller <davem@davemloft.net>
Bug reported by Alexander Beregalov.
Before we dereference the stack frame or try to peek at the
pt_regs magic value, make sure the entire object is within
the kernel stack bounds.
Signed-off-by: David S. Miller <davem@davemloft.net>
All of the xcall delivery implementation is cpumask agnostic, so
we can pass around pointers to const cpumask_t objects everywhere.
The sad remaining case is the argument to arch_send_call_function_ipi().
Signed-off-by: David S. Miller <davem@davemloft.net>
It can eat up a lot of stack space when NR_CPUS is large.
We retain some of it's functionality by reporting at least one
of the cpu's which are seen in error state.
Signed-off-by: David S. Miller <davem@davemloft.net>
Then modify all of the xcall dispatch implementations get passed and
use this information.
Now all of the xcall dispatch implementations do not need to be mindful
of details such as "is current cpu in the list?" and "is cpu online?"
Signed-off-by: David S. Miller <davem@davemloft.net>
This just facilitates the next changeset where we'll be building
the cpu list and mondo block in this helper function.
Signed-off-by: David S. Miller <davem@davemloft.net>
Ideally this could be simplified further such that we could pass
the pointer down directly into the xcall_deliver() implementation.
But if we do that we need to do the "cpu_online(cpu)" and
"cpu != self" checks down in those functions.
Signed-off-by: David S. Miller <davem@davemloft.net>
For these cases the callers make sure:
1) The cpus indicated are online.
2) The current cpu is not in the list of indicated cpus.
Therefore we can pass a pointer to the mask directly.
One of the motivations in this transformation is to make use of
"&cpumask_of_cpu(cpu)" which evaluates to a pointer to constant
data in the kernel and thus takes up no stack space.
Hopefully someone in the future will change the interface of
arch_send_call_function_ipi() such that it passes a const cpumask_t
pointer so that this will optimize ever further.
Signed-off-by: David S. Miller <davem@davemloft.net>
Removed duplicated #include <linux/tracehook.h> in
arch/sparc64/kernel/signal.c.
Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based upon a bug report by Mariusz Kozlowski
It uses smp_call_function_masked() now, which has a preemption-disabled
requirement.
Signed-off-by: David S. Miller <davem@davemloft.net>
That's the userland thread register, so we should never try to change
it like this.
Based upon glibc bug nptl/6577 and suggestions by Jakub Jelinek.
Signed-off-by: David S. Miller <davem@davemloft.net>
The story is that what we used to do when we actually used
smp_report_regs() is that if you specifically only wanted to have the
current cpu's registers dumped you would call "__show_regs()"
otherwise you would call show_regs() which also invoked
smp_report_regs().
Now that we killed off smp_report_regs() there is no longer any
reason to have these two routines, just show_regs() is sufficient.
Also kill off a stray declaration of show_regs() in sparc64_ksym.c
Signed-off-by: David S. Miller <davem@davemloft.net>
All the call sites are #if 0'd out and we have a much more
useful global cpu dumping facility these days. smp_report_regs()
is way too verbose to be usable.
Signed-off-by: David S. Miller <davem@davemloft.net>
It just clutters everything up and even though I wrote that hack I
can't remember having used it in the last 5 years or so.
Signed-off-by: David S. Miller <davem@davemloft.net>
Record one more level of stack frame program counter.
Particularly when lockdep and all sorts of spinlock debugging is
enabled, figuring out the caller of spin_lock() is difficult when the
cpu is stuck on the lock.
Signed-off-by: David S. Miller <davem@davemloft.net>
Call the standard hook after setting up signal handlers.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds TIF_NOTIFY_RESUME support for sparc64.
When set, we call tracehook_notify_resume() on the way to user mode.
Signed-off-by: Roland McGrath <roland@redhat.com>
This changes sparc64 syscall tracing to use the new tracehook.h entry
points.
[ Add assembly changes to force an immediate -ENOSYS return from
the system call when syscall_trace() returns non-zero at syscall
entry. -DaveM ]
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The majority of this patch was created by the following script:
***
ASM=arch/sparc/include/asm
mkdir -p $ASM
git mv include/asm-sparc64/ftrace.h $ASM
git rm include/asm-sparc64/*
git mv include/asm-sparc/* $ASM
sed -ie 's/asm-sparc64/asm/g' $ASM/*
sed -ie 's/asm-sparc/asm/g' $ASM/*
***
The rest was an update of the top-level Makefile to use sparc
for header files when sparc64 is being build.
And a small fixlet to pick up the correct unistd.h from
sparc64 code.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Remove arch-specific show_mem() in favor of the generic version.
This also removes the following redundant information display:
- free swap pages, printed by show_swap_cache_info()
- pages in swapcache, printed by show_swap_cache_info()
- dirty pages, writeback pages, mapped pages, slab pages,
pagetables pages, printed by show_free_areas()
where show_mem() calls show_free_areas(), which calls
show_swap_cache_info().
Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
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>
This wires up the recently added Wire up signalfd4, eventfd2,
epoll_create1, dup3, pipe2, and inotify_init1 system calls.
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently list of kretprobe instances are stored in kretprobe object (as
used_instances,free_instances) and in kretprobe hash table. We have one
global kretprobe lock to serialise the access to these lists. This causes
only one kretprobe handler to execute at a time. Hence affects system
performance, particularly on SMP systems and when return probe is set on
lot of functions (like on all systemcalls).
Solution proposed here gives fine-grain locks that performs better on SMP
system compared to present kretprobe implementation.
Solution:
1) Instead of having one global lock to protect kretprobe instances
present in kretprobe object and kretprobe hash table. We will have
two locks, one lock for protecting kretprobe hash table and another
lock for kretporbe object.
2) We hold lock present in kretprobe object while we modify kretprobe
instance in kretprobe object and we hold per-hash-list lock while
modifying kretprobe instances present in that hash list. To prevent
deadlock, we never grab a per-hash-list lock while holding a kretprobe
lock.
3) We can remove used_instances from struct kretprobe, as we can
track used instances of kretprobe instances using kretprobe hash
table.
Time duration for kernel compilation ("make -j 8") on a 8-way ppc64 system
with return probes set on all systemcalls looks like this.
cacheline non-cacheline Un-patched kernel
aligned patch aligned patch
===============================================================================
real 9m46.784s 9m54.412s 10m2.450s
user 40m5.715s 40m7.142s 40m4.273s
sys 2m57.754s 2m58.583s 3m17.430s
===========================================================
Time duration for kernel compilation ("make -j 8) on the same system, when
kernel is not probed.
=========================
real 9m26.389s
user 40m8.775s
sys 2m7.283s
=========================
Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com>
Signed-off-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
nohz: adjust tick_nohz_stop_sched_tick() call of s390 as well
nohz: prevent tick stop outside of the idle loop
This patch introduces the new syscall pipe2 which is like pipe but it also
takes an additional parameter which takes a flag value. This patch implements
the handling of O_CLOEXEC for the flag. I did not add support for the new
syscall for the architectures which have a special sys_pipe implementation. I
think the maintainers of those archs have the chance to go with the unified
implementation but that's up to them.
The implementation introduces do_pipe_flags. I did that instead of changing
all callers of do_pipe because some of the callers are written in assembler.
I would probably screw up changing the assembly code. To avoid breaking code
do_pipe is now a small wrapper around do_pipe_flags. Once all callers are
changed over to do_pipe_flags the old do_pipe function can be removed.
The following test must be adjusted for architectures other than x86 and
x86-64 and in case the syscall numbers changed.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>
#ifndef __NR_pipe2
# ifdef __x86_64__
# define __NR_pipe2 293
# elif defined __i386__
# define __NR_pipe2 331
# else
# error "need __NR_pipe2"
# endif
#endif
int
main (void)
{
int fd[2];
if (syscall (__NR_pipe2, fd, 0) != 0)
{
puts ("pipe2(0) failed");
return 1;
}
for (int i = 0; i < 2; ++i)
{
int coe = fcntl (fd[i], F_GETFD);
if (coe == -1)
{
puts ("fcntl failed");
return 1;
}
if (coe & FD_CLOEXEC)
{
printf ("pipe2(0) set close-on-exit for fd[%d]\n", i);
return 1;
}
}
close (fd[0]);
close (fd[1]);
if (syscall (__NR_pipe2, fd, O_CLOEXEC) != 0)
{
puts ("pipe2(O_CLOEXEC) failed");
return 1;
}
for (int i = 0; i < 2; ++i)
{
int coe = fcntl (fd[i], F_GETFD);
if (coe == -1)
{
puts ("fcntl failed");
return 1;
}
if ((coe & FD_CLOEXEC) == 0)
{
printf ("pipe2(O_CLOEXEC) does not set close-on-exit for fd[%d]\n", i);
return 1;
}
}
close (fd[0]);
close (fd[1]);
puts ("OK");
return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On 32-bit architectures PAGE_ALIGN() truncates 64-bit values to the 32-bit
boundary. For example:
u64 val = PAGE_ALIGN(size);
always returns a value < 4GB even if size is greater than 4GB.
The problem resides in PAGE_MASK definition (from include/asm-x86/page.h for
example):
#define PAGE_SHIFT 12
#define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE-1))
...
#define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE-1)&PAGE_MASK)
The "~" is performed on a 32-bit value, so everything in "and" with
PAGE_MASK greater than 4GB will be truncated to the 32-bit boundary.
Using the ALIGN() macro seems to be the right way, because it uses
typeof(addr) for the mask.
Also move the PAGE_ALIGN() definitions out of include/asm-*/page.h in
include/linux/mm.h.
See also lkml discussion: http://lkml.org/lkml/2008/6/11/237
[akpm@linux-foundation.org: fix drivers/media/video/uvc/uvc_queue.c]
[akpm@linux-foundation.org: fix v850]
[akpm@linux-foundation.org: fix powerpc]
[akpm@linux-foundation.org: fix arm]
[akpm@linux-foundation.org: fix mips]
[akpm@linux-foundation.org: fix drivers/media/video/pvrusb2/pvrusb2-dvb.c]
[akpm@linux-foundation.org: fix drivers/mtd/maps/uclinux.c]
[akpm@linux-foundation.org: fix powerpc]
Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
