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

From: Steven Rostedt
Date: Tue Jan 25 2011 - 23:10:47 EST


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

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:


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(-)
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/