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SubjectRe: [PATCH 0/3] [GIT PULL][v2.6.38] tracing: fix unaligned event arrays

* Steven Rostedt <rostedt@goodmis.org> wrote:

> Ingo,
>
> It was discovered that the alignment of the trace event sections
> break sparc64. The trace events are created by linker magic, so
> gcc does not realize that the structures being allocated will end
> up in an array. Without adding any alignment, x86_64 would create
> the trace event arrays with holes that would break reading the
> events in serial. The fix for that was to force a align(4) to
> keep gcc and the linker from spacing the event structures at various
> alignments. But recent changes have caused this change to break
> sparc due to bad alignment in the structures, caused by the 4 byte
> alignment.
>
> After some discussions, Mathieu came up with the following patch set
> to correctly fix the alignment issues with the trace event structures.
>
> Please pull the latest tip/perf/urgent tree, which can be found at:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git
> tip/perf/urgent
>
>
> Mathieu Desnoyers (3):
> Introduce __u64_aligned and U64_ALIGN() for structure alignment in custom sections
> tracing: Fix sparc64 alignment crash with __u64_aligned/U64_ALIGN()
> tracepoints: Use __u64_aligned/U64_ALIGN()
>
> ----
> include/asm-generic/vmlinux.lds.h | 27 +++++++++++-------
> include/linux/align-section.h | 54 +++++++++++++++++++++++++++++++++++++
> include/linux/compiler.h | 8 +++--
> include/linux/ftrace_event.h | 2 +-
> include/linux/syscalls.h | 12 ++++----
> include/linux/tracepoint.h | 12 +++-----
> include/trace/ftrace.h | 8 +++---
> include/trace/syscall.h | 2 +-
> kernel/trace/trace.h | 2 +-
> kernel/trace/trace_export.c | 2 +-
> 10 files changed, 94 insertions(+), 35 deletions(-)

Pulled, thanks a lot Steve!

Ingo


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