We're approaching 20 locations where we need to check for ELF ABI v2.
That's fine, except the logic is a bit awkward, because we have to check
that _CALL_ELF is defined and then what its value is.
So check it once in asm/types.h and define PPC64_ELF_ABI_v2 when ELF ABI
v2 is detected.
We also have a few places where what we're really trying to check is
that we are using the 64-bit v1 ABI, ie. function descriptors. So also
add a #define for that, which simplifies several checks.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The gcc switch -mprofile-kernel defines a new ABI for calling _mcount()
very early in the function with minimal overhead.
Although mprofile-kernel has been available since GCC 3.4, there were
bugs which were only fixed recently. Currently it is known to work in
GCC 4.9, 5 and 6.
Additionally there are two possible code sequences generated by the
flag, the first uses mflr/std/bl and the second is optimised to omit the
std. Currently only gcc 6 has the optimised sequence. This patch
supports both sequences.
Initial work started by Vojtech Pavlik, used with permission.
Key changes:
- rework _mcount() to work for both the old and new ABIs.
- implement new versions of ftrace_caller() and ftrace_graph_caller()
which deal with the new ABI.
- updates to __ftrace_make_nop() to recognise the new mcount calling
sequence.
- updates to __ftrace_make_call() to recognise the nop'ed sequence.
- implement ftrace_modify_call().
- updates to the module loader to surpress the toc save in the module
stub when calling mcount with the new ABI.
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Always we use type unsigned long to format the ip address, since the
value of ip address is never the negative.
This patch uses type unsigned long, instead of long, to format the ip
address. The code is more clearly to be viewed by using type unsigned
long, although it is correct by using either unsigned long or long.
Link: http://lkml.kernel.org/r/1436694744-16747-1-git-send-email-mhuang@redhat.com
Cc: Minfei Huang <mnfhuang@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
ABIv2 doesn't have function descriptors or dot symbols. One
new thing it does add is a function global and a local entry
point, so add that to our _GLOBAL macro.
Signed-off-by: Anton Blanchard <anton@samba.org>
This patch implements the raw syscall tracepoints on PowerPC and exports
them for ftrace syscalls to use.
To minimise reworking existing code, I slightly re-ordered the thread
info flags such that the new TIF_SYSCALL_TRACEPOINT bit would still fit
within the 16 bits of the andi. instruction's UI field. The instructions
in question are in /arch/powerpc/kernel/entry_{32,64}.S to and the
_TIF_SYSCALL_T_OR_A with the thread flags to see if system call tracing
is enabled.
In the case of 64bit PowerPC, arch_syscall_addr and
arch_syscall_match_sym_name are overridden to allow ftrace syscalls to
work given the unusual system call table structure and symbol names that
start with a period.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Impact: clean up
Use a macro to save and restore the registers for PowerPC32,
since that code is duplicated.
This is similar to the work done by Cyrill Gorcunov for the
mcount code in x86_64.
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Impact: Allow 64 bit PowerPC to trace modules with dynamic ftrace
This adds code to handle the PPC64 module trampolines, and allows for
PPC64 to use dynamic ftrace.
Thanks to Paul Mackerras for these updates:
- fix the mod and rec->arch.mod NULL checks.
- fix to is_bl_op compare.
Thanks to Milton Miller for:
- finding the nasty race with using two nops, and recommending
instead that I use a branch 8 forward.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: update to PowerPC ftrace arch API
This patch converts PowerPC to use the new dynamic ftrace arch API.
Thanks to Paul Mackennas for pointing out the mistakes of my original
test_24bit_addr function.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Due to confusion between the ftrace infrastructure and the gcc profiling
tracer "ftrace", this patch renames the config options from FTRACE to
FUNCTION_TRACER. The other two names that are offspring from FTRACE
DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same.
This patch was generated mostly by script, and partially by hand.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
from include/asm-powerpc. This is the result of a
mkdir arch/powerpc/include/asm
git mv include/asm-powerpc/* arch/powerpc/include/asm
Followed by a few documentation/comment fixups and a couple of places
where <asm-powepc/...> was being used explicitly. Of the latter only
one was outside the arch code and it is a driver only built for powerpc.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Michael Ellerman