kernel_optimize_test/arch/x86
Steven Rostedt 8a4d0a687a ftrace: Use breakpoint method to update ftrace caller
On boot up and module load, it is fine to modify the code directly,
without the use of breakpoints. This is because boot up modification
is done before SMP is initialized, thus the modification is serial,
and module load is done before the module executes.

But after that we must use a SMP safe method to modify running code.
Otherwise, if we are running the function tracer and update its
function (by starting off the stack tracer, or perf tracing)
the change of the function called by the ftrace trampoline is done
directly. If this is being executed on another CPU, that CPU may
take a GPF and crash the kernel.

The breakpoint method is used to change the nops at all the functions, but
the change of the ftrace callback handler itself was still using a
direct modification. If tracing was enabled and the function callback
was changed then another CPU could fault if it was currently calling
the original callback. This modification must use the breakpoint method
too.

Note, the direct method is still used for boot up and module load.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-05-31 23:12:19 -04:00
..
boot Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-23 11:16:40 -07:00
configs x86/kconfig: Remove CONFIG_TR=y from the defconfigs 2012-03-24 08:18:03 +01:00
crypto crypto: aesni-intel - move more common code to ablk_init_common 2012-05-15 17:25:33 +10:00
ia32 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-05-23 18:11:45 -07:00
include/asm ftrace: Synchronize variable setting with breakpoints 2012-05-31 23:12:17 -04:00
kernel ftrace: Use breakpoint method to update ftrace caller 2012-05-31 23:12:19 -04:00
kvm KVM: ensure async PF event wakes up vcpu from halt 2012-05-06 14:56:54 +03:00
lguest
lib Merge branch 'x86-extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-23 10:44:35 -07:00
math-emu x86: Rename trap_no to trap_nr in thread_struct 2012-03-13 06:24:09 +01:00
mm Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2012-05-23 17:42:39 -07:00
net bpf jit: Let the x86 jit handle negative offsets 2012-04-03 18:01:41 -04:00
oprofile x86: Factor out TIF_IA32 from 32-bit address space 2012-02-20 12:48:46 -08:00
pci Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-23 11:16:40 -07:00
platform Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-23 11:16:40 -07:00
power x86, kvm: Call restore_sched_clock_state() only after %gs is initialized 2012-04-02 13:53:00 +02:00
syscalls Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-03-29 18:12:23 -07:00
tools x86, relocs: When printing an error, say relative or absolute 2012-05-18 19:50:02 -07:00
um Merge branch 'x86-extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-23 10:44:35 -07:00
vdso Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-03-29 18:12:23 -07:00
video
xen Merge branch 'x86-extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-23 10:44:35 -07:00
.gitignore x86/kprobes: Add arch/x86/tools/insn_sanity to .gitignore 2012-01-16 08:21:59 +01:00
Kbuild
Kconfig Merge branch 'delete-mca' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2012-05-23 17:12:06 -07:00
Kconfig.cpu x86: Tighten dependencies of CPU_SUP_*_32 2012-03-08 10:57:34 +01:00
Kconfig.debug
Makefile md updates for 3.5 2012-05-23 17:08:40 -07:00
Makefile_32.cpu
Makefile.um um: fix linker script generation 2012-04-09 13:59:00 -04:00