linux-toradex.git/arch/s390/kernel/entry.S, branch v2.6.32

[S390] s390: fix single stepping on svc0

2009-11-13T14:45:03+00:00

On s390 there are two ways of specifying the system call number for
the svc instruction. The standard way is to use the immediate field
in the instruction (or to use EXecute for values unknown during
assemble time). This can encode 256 system calls.
The kernel ABI also allows to put the system call number in r1 and
then execute svc 0 to enable system call numbers > 255.

It turns out that single stepping svc 0 is broken, since the PER
program check handler uses r1. We have to use a different register.

Signed-off-by: Christian Borntraeger 
Signed-off-by: Martin Schwidefsky

Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-09-11T20:24:03+00:00

* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (105 commits)
  ring-buffer: only enable ring_buffer_swap_cpu when needed
  ring-buffer: check for swapped buffers in start of committing
  tracing: report error in trace if we fail to swap latency buffer
  tracing: add trace_array_printk for internal tracers to use
  tracing: pass around ring buffer instead of tracer
  tracing: make tracing_reset safe for external use
  tracing: use timestamp to determine start of latency traces
  tracing: Remove mentioning of legacy latency_trace file from documentation
  tracing/filters: Defer pred allocation, fix memory leak
  tracing: remove users of tracing_reset
  tracing: disable buffers and synchronize_sched before resetting
  tracing: disable update max tracer while reading trace
  tracing: print out start and stop in latency traces
  ring-buffer: disable all cpu buffers when one finds a problem
  ring-buffer: do not count discarded events
  ring-buffer: remove ring_buffer_event_discard
  ring-buffer: fix ring_buffer_read crossing pages
  ring-buffer: remove unnecessary cpu_relax
  ring-buffer: do not swap buffers during a commit
  ring-buffer: do not reset while in a commit
  ...

[S390] move (io|sysc)_restore_trace_psw into .data section

2009-09-11T08:29:47+00:00

The sysc_restore_trace_psw and io_restore_trace_psw storage locations
are created in the .text section. When creating and IPLing from a named
saved system (NSS), writing to these locations causes a protection exception
(because the .text section is mapped as shared read-only in the NSS).

To permit write access, move the storage locations into the .data section.

The problem occurs only when CONFIG_TRACE_IRQFLAGS is set.
The git commmit that has introduced these variables is:
411788ea7fca01ee803af8225ac35807b4d02050

Signed-off-by: Hendrik Brueckner 
Signed-off-by: Martin Schwidefsky

tracing: Rename FTRACE_SYSCALLS for tracepoints

2009-08-25T22:17:35+00:00

s/HAVE_FTRACE_SYSCALLS/HAVE_SYSCALL_TRACEPOINTS/g
s/TIF_SYSCALL_FTRACE/TIF_SYSCALL_TRACEPOINT/g

The syscall enter/exit tracing is no longer specific to just ftrace, so
they now have names that reflect their tie to tracepoints instead.

Signed-off-by: Josh Stone 
Cc: Jason Baron 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Li Zefan 
Cc: Steven Rostedt 
Cc: Peter Zijlstra 
Cc: Mathieu Desnoyers 
Cc: Jiaying Zhang 
Cc: Martin Bligh 
Cc: Lai Jiangshan 
Cc: Paul Mundt 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
LKML-Reference: <1251150194-1713-2-git-send-email-jistone@redhat.com>
Signed-off-by: Frederic Weisbecker

[S390] ftrace: add system call tracer support

2009-06-12T08:27:39+00:00

System call tracer support for s390.

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

[S390] secure computing arch backend

2009-06-12T08:27:31+00:00

Enable secure computing on s390 as well.

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

[S390] cpu hotplug and accounting values

2009-04-14T13:37:27+00:00

Reset the cpu timer to the maximum value and correctly initialize the
cpu accounting values in the lowcore when the cpu is started.

Signed-off-by: Martin Schwidefsky

[PATCH] improve idle cputime accounting

2008-12-31T14:11:48+00:00

Distinguish the cputime of the idle process where idle is actually using
cpu cycles from the cputime where idle is sleeping on an enabled wait psw.
The former is accounted as system time, the later as idle time.

Signed-off-by: Martin Schwidefsky

[S390] Remove config options.

2008-12-25T12:39:15+00:00

On s390 we always want to run with precise cputime accounting.
Remove the config options VIRT_TIMER and VIRT_CPU_ACCOUNTING.

Signed-off-by: Martin Schwidefsky

[S390] audit: get s390 ret_from_fork in sync with other architectures

2008-12-25T12:38:07+00:00

	On s390 we have ret_from_fork jump not to the "do all work we
normally do on return from syscall" as on x86, ppc, etc., but to the
"do all such work except audit".  Historical reasons - the codepath
triggered when we have AUDIT process flag set is separated from the
normall one and they converge at sysc_return, which is the common
part of post-syscall work.  And does not include calling audit_syscall_exit() -
that's done in the end of sysc_tracesys path, just before that path jumps
to sysc_return.

	IOW, the child returning from fork()/clone()/vfork() doesn't
call audit_syscall_exit() at all, so no matter what we do with its
audit context, we are not going to see the audit entry.

	The fix is simple: have ret_from_fork go to the point just past
the call of sys_.... in the 'we have AUDIT flag set' path.  There we
have (64bit variant; for 31bit the situation is the same):
sysc_tracenogo:
        tm      __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
        jz      sysc_return
        la      %r2,SP_PTREGS(%r15)     # load pt_regs
        larl    %r14,sysc_return        # return point is sysc_return
        jg      do_syscall_trace_exit
which is precisely what we need - check the flag, bugger off to sysc_return
if not set, otherwise call do_syscall_trace_exit() and bugger off to
sysc_return.  r9 has just been properly set by ret_from_fork itself,
so we are fine.

	Tested on s390x, seems to work fine.  WARNING: it's been about
16 years since my last contact with 3X0 assembler[1], so additional
review would be very welcome.  I don't think I've managed to screw it
up, but...

[1] that *was* in another country and besides, the box is dead...

Signed-off-by: Al Viro 
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky