linux-toradex.git/arch/powerpc/kernel/uprobes.c, branch v3.14.8

uprobes/powerpc: Kill arch_uprobe->ainsn

2013-11-20T15:31:01+00:00

powerpc has both arch_uprobe->insn and arch_uprobe->ainsn to
make the generic code happy. This is no longer needed after
the previous change, powerpc can just use "u32 insn".

Signed-off-by: Oleg Nesterov 
Acked-by: Srikar Dronamraju 
Acked-by: Ananth N Mavinakayanahalli

uretprobes/powerpc: Hijack return address

2013-04-13T13:31:56+00:00

Hijack the return address and replace it with a trampoline address.
PowerPC implementation.

Signed-off-by: Anton Arapov 
Acked-by: Ananth N Mavinakayanahalli 
Acked-by: Srikar Dronamraju 
Signed-off-by: Oleg Nesterov

uprobes/powerpc: Remove additional trap instruction check

2013-04-04T11:57:04+00:00

prepare_uprobe() already checks if the underlying unstruction
(on file) is a trap variant. We don't need to check this again.

Signed-off-by: Ananth N Mavinakayanahalli 
Acked-by: Srikar Dronamraju 
Signed-off-by: Oleg Nesterov

uprobes/powerpc: Teach uprobes to ignore gdb breakpoints

2013-04-04T11:57:04+00:00

Powerpc has many trap variants that could be used by entities like gdb.
Currently, running gdb on a program being traced by uprobes causes an
endless loop since uprobes doesn't understand that the trap was inserted
by some other entity and a SIGTRAP needs to be delivered.

Teach uprobes to ignore breakpoints that do not belong to it.

Signed-off-by: Ananth N Mavinakayanahalli 
Acked-by: Srikar Dronamraju 
Signed-off-by: Oleg Nesterov

uprobes/powerpc: Do not use arch_uprobe_*_step() helpers

2012-11-03T16:15:12+00:00

No functional changes.

powerpc is the only user of arch_uprobe_enable/disable_step() helpers,
but they should die. They can not be used correctly, every arch needs
its own implementation (like x86 does). And they do not really help
even as initial-and-almost-working code, arch_uprobe_*_xol() hooks can
easily use user_enable/disable_single_step() directly.

Change arch_uprobe_*_step() to do nothing, and convert powerpc to use
ptrace helpers. This is equally wrong, powerpc needs the arch-specific
fixes.

Signed-off-by: Oleg Nesterov 
Acked-by: Ananth N Mavinakayanahalli 
Acked-by: Srikar Dronamraju

powerpc: Uprobes port to powerpc

2012-09-05T05:35:19+00:00

This is the port of uprobes to powerpc. Usage is similar to x86.

[root@xxxx ~]# ./bin/perf probe -x /lib64/libc.so.6 malloc
Added new event:
  probe_libc:malloc    (on 0xb4860)

You can now use it in all perf tools, such as:

	perf record -e probe_libc:malloc -aR sleep 1

[root@xxxx ~]# ./bin/perf record -e probe_libc:malloc -aR sleep 20
[ perf record: Woken up 22 times to write data ]
[ perf record: Captured and wrote 5.843 MB perf.data (~255302 samples) ]
[root@xxxx ~]# ./bin/perf report --stdio
...

    69.05%           tar  libc-2.12.so   [.] malloc
    28.57%            rm  libc-2.12.so   [.] malloc
     1.32%  avahi-daemon  libc-2.12.so   [.] malloc
     0.58%          bash  libc-2.12.so   [.] malloc
     0.28%          sshd  libc-2.12.so   [.] malloc
     0.08%    irqbalance  libc-2.12.so   [.] malloc
     0.05%         bzip2  libc-2.12.so   [.] malloc
     0.04%         sleep  libc-2.12.so   [.] malloc
     0.03%    multipathd  libc-2.12.so   [.] malloc
     0.01%      sendmail  libc-2.12.so   [.] malloc
     0.01%     automount  libc-2.12.so   [.] malloc

The trap_nr addition patch is a prereq.

Signed-off-by: Ananth N Mavinakayanahalli 
Signed-off-by: Benjamin Herrenschmidt