OpenCloudOS-Kernel/arch
Steven Rostedt 722b3c7469 ftrace/graph: Trace function entry before updating index
Currently the index to the ret_stack is updated and the real return address
is saved in the ret_stack. Then we call the trace function. The trace
function could decide that it doesn't want to trace this function
(ex. set_graph_function does not match) and it will return 0 which means
not to trace this call.

The normal function graph tracer has this code:

	if (!(trace->depth || ftrace_graph_addr(trace->func)) ||
	      ftrace_graph_ignore_irqs())
		return 0;

What this states is, if the trace depth (which is curr_ret_stack)
is zero (top of nested functions) then test if we want to trace this
function. If this function is not to be traced, then return  0 and
the rest of the function graph tracer logic will not trace this function.

The problem arises when an interrupt comes in after we updated the
curr_ret_stack. The next function that gets called will have a trace->depth
of 1. Which fools this trace code into thinking that we are in a nested
function, and that we should trace. This causes interrupts to be traced
when they should not be.

The solution is to trace the function first and then update the ret_stack.

Reported-by: zhiping zhong <xzhong86@163.com>
Reported-by: wu zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-03-10 10:34:43 -05:00
..
alpha alpha: Enable GENERIC_HARDIRQS_NO_DEPRECATED 2011-03-02 14:58:00 -05:00
arm Merge branch 's5p-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung 2011-03-07 20:46:39 -08:00
avr32 avr32: add missing include causing undefined pgtable_page_* references 2011-01-26 12:35:15 +01:00
blackfin Blackfin: iflush: update anomaly 05000491 workaround 2011-03-04 01:27:01 -05:00
cris Drop redundant __param section for CRISv32. 2011-02-23 08:00:47 -08:00
frv frv: Use generic irq Kconfig 2011-01-21 11:55:32 +01:00
h8300 h8300: Use generic irq Kconfig 2011-01-21 11:55:24 +01:00
ia64 ia64: Use generic irq Kconfig 2011-01-21 11:55:32 +01:00
m32r m32r: Fixup last __do_IRQ leftover 2011-02-05 21:46:35 +01:00
m68k m68knommu: add optimize memmove() function 2011-02-16 09:43:16 +10:00
m68knommu m68knommu: set flow handler for secondary interrupt controller of 5249 2011-02-16 09:43:46 +10:00
microblaze microblaze: Fix msr instruction detection 2011-02-07 19:13:01 +01:00
mips genirq: Remove __do_IRQ 2011-01-21 11:55:31 +01:00
mn10300 mn10300: Use generic irq Kconfig 2011-01-21 11:55:33 +01:00
parisc console: rename acquire/release_console_sem() to console_lock/unlock() 2011-01-26 10:50:06 +10:00
powerpc powerpc: Fix call to flush_ptrace_hw_breakpoint() 2011-03-02 14:56:49 +11:00
s390 [S390] net: provide architecture specific NET_SKB_PAD 2011-02-17 13:13:59 +01:00
score score: Use generic irq Kconfig 2011-01-21 11:55:34 +01:00
sh Merge branch 'sh/st-integration' into sh/urgent 2011-02-15 16:26:41 +09:00
sparc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6 2011-02-17 17:51:27 -08:00
tile tile: Use generic irq Kconfig 2011-01-21 11:55:34 +01:00
um um: Use generic irq Kconfig 2011-01-21 11:55:35 +01:00
x86 ftrace/graph: Trace function entry before updating index 2011-03-10 10:34:43 -05:00
xtensa kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT 2011-01-20 17:02:05 -08:00
.gitignore
Kconfig [S390] mutex: Introduce arch_mutex_cpu_relax() 2011-01-05 12:47:31 +01:00