linux/arch/powerpc
Anton Blanchard 1bf4af1650 powerpc: tracing: Add powerpc tracepoints for interrupt entry and exit
This adds powerpc-specific tracepoints for interrupt entry and exit.

While we already have generic irq_handler_entry and irq_handler_exit
tracepoints there are cases on our virtualised powerpc machines where an
interrupt is presented to the OS, but subsequently handled by the hypervisor.
This means no OS interrupt handler is invoked.

Here is an example on a POWER6 machine with the patch below applied:

<idle>-0     [006]  3243.949840744: irq_entry: pt_regs=c0000000ce31fb10
<idle>-0     [006]  3243.949850520: irq_exit: pt_regs=c0000000ce31fb10

<idle>-0     [007]  3243.950218208: irq_entry: pt_regs=c0000000ce323b10
<idle>-0     [007]  3243.950224080: irq_exit: pt_regs=c0000000ce323b10

<idle>-0     [000]  3244.021879320: irq_entry: pt_regs=c000000000a63aa0
<idle>-0     [000]  3244.021883616: irq_handler_entry: irq=87 handler=eth0
<idle>-0     [000]  3244.021887328: irq_handler_exit: irq=87 return=handled
<idle>-0     [000]  3244.021897408: irq_exit: pt_regs=c000000000a63aa0

Here we see two phantom interrupts (no handler was invoked), followed
by a real interrupt for eth0. Without the tracepoints in this patch we
would have missed the phantom interrupts.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-28 16:13:03 +11:00
..
boot Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next 2009-09-23 15:37:02 -07:00
configs Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2009-09-15 09:51:09 -07:00
include/asm powerpc: tracing: Add powerpc tracepoints for interrupt entry and exit 2009-10-28 16:13:03 +11:00
kernel powerpc: tracing: Add powerpc tracepoints for interrupt entry and exit 2009-10-28 16:13:03 +11:00
kvm const: constify remaining file_operations 2009-10-01 16:11:11 -07:00
lib powerpc: Add configurable -Werror for arch/powerpc 2009-06-16 14:15:45 +10:00
math-emu powerpc/math-emu: Fix efp dependence 2009-03-11 06:00:08 -05:00
mm powerpc/8xx: Fix regression introduced by cache coherency rewrite 2009-09-24 15:56:30 +10:00
oprofile powerpc: Remove unnecessary semicolons 2009-07-08 13:50:21 +10:00
platforms const: constify remaining file_operations 2009-10-01 16:11:11 -07:00
sysdev powerpc: Change archdata dma_data to a union 2009-09-24 15:31:43 +10:00
xmon powerpc/4xx: Fix erroneous xmon warning on PowerPC 4xx 2009-09-24 15:31:49 +10:00
Kconfig powerpc: Increase NODES_SHIFT on 64bit from 4 to 8 2009-09-24 15:31:46 +10:00
Kconfig.debug powerpc: Add configurable -Werror for arch/powerpc 2009-06-16 14:15:45 +10:00
Makefile powerpc: Check for unsupported relocs when using CONFIG_RELOCATABLE 2009-09-24 15:31:40 +10:00
relocs_check.pl powerpc: Check for unsupported relocs when using CONFIG_RELOCATABLE 2009-09-24 15:31:40 +10:00