linux_dsm_epyc7002/kernel/trace
Steven Rostedt 3d56e331b6 tracing: Replace syscall_meta_data struct array with pointer array
Currently the syscall_meta structures for the syscall tracepoints are
placed in the __syscall_metadata section, and at link time, the linker
makes one large array of all these syscall metadata structures. On boot
up, this array is read (much like the initcall sections) and the syscall
data is processed.

The problem is that there is no guarantee that gcc will place complex
structures nicely together in an array format. Two structures in the
same file may be placed awkwardly, because gcc has no clue that they
are suppose to be in an array.

A hack was used previous to force the alignment to 4, to pack the
structures together. But this caused alignment issues with other
architectures (sparc).

Instead of packing the structures into an array, the structures' addresses
are now put into the __syscall_metadata section. As pointers are always the
natural alignment, gcc should always pack them tightly together
(otherwise initcall, extable, etc would also fail).

By having the pointers to the structures in the section, we can still
iterate the trace_events without causing unnecessary alignment problems
with other architectures, or depending on the current behaviour of
gcc that will likely change in the future just to tick us kernel developers
off a little more.

The __syscall_metadata section is also moved into the .init.data section
as it is now only needed at boot up.

Suggested-by: David Miller <davem@davemloft.net>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-02-03 09:29:06 -05:00
..
blktrace.c block: ensure that completion error gets properly traced 2011-01-10 09:06:44 +01:00
ftrace.c Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl 2010-10-22 10:52:56 -07:00
Kconfig perf: Clean up power events by introducing new, more generic ones 2011-01-04 08:16:54 +01:00
Makefile tracing: Fix TRACE_EVENT power tracepoint creation 2011-01-07 23:26:29 -05:00
power-traces.c perf: Clean up power events by introducing new, more generic ones 2011-01-04 08:16:54 +01:00
ring_buffer_benchmark.c ring-buffer: Make benchmark handle missed events 2010-04-27 13:26:58 -04:00
ring_buffer.c ring_buffer: Off-by-one and duplicate events in ring_buffer_read_page 2010-12-23 12:09:30 -05:00
trace_branch.c tracing: Allow events to share their print functions 2010-05-14 14:20:32 -04:00
trace_clock.c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-08-06 09:39:22 -07:00
trace_entries.h tree-wide: fix comment/printk typos 2010-11-01 15:38:34 -04:00
trace_event_perf.c tracing: New flag to allow non privileged users to use a trace event 2010-11-18 14:37:40 +01:00
trace_events_filter.c tracing: Remove test of NULL define_fields callback 2010-06-28 17:12:52 -04:00
trace_events.c tracing: Replace trace_event struct array with pointer array 2011-02-02 21:37:13 -05:00
trace_export.c tracing: Replace trace_event struct array with pointer array 2011-02-02 21:37:13 -05:00
trace_functions_graph.c tracing: Remove parent recording in latency tracer graph options 2010-10-18 10:53:38 -04:00
trace_functions.c tracing: Remove ftrace_preempt_disable/enable 2010-06-03 19:32:38 -04:00
trace_irqsoff.c lockdep: Move early boot local IRQ enable/disable status to init/main.c 2011-01-20 13:32:33 +01:00
trace_kdb.c kdb,ftdump: Remove reference to internal kdb include 2010-10-22 15:34:11 -05:00
trace_kprobe.c Remove duplicate includes from many files 2010-10-27 18:03:18 -07:00
trace_mmiotrace.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
trace_nop.c tracing/ftrace: make nop-tracer use polling wait for events on pipe 2009-03-23 09:22:15 +01:00
trace_output.c Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core 2010-07-23 09:10:29 +02:00
trace_output.h tracing: Allow events to share their print functions 2010-05-14 14:20:32 -04:00
trace_printk.c tracing: Remove markers 2009-09-18 21:22:08 +02:00
trace_sched_switch.c tracing: Let tracepoints have data passed to tracepoint callbacks 2010-05-14 09:50:34 -04:00
trace_sched_wakeup.c tracing: Fix compile issue for trace_sched_wakeup.c 2010-10-19 10:56:19 -04:00
trace_selftest_dynamic.c
trace_selftest.c sched: Constify function scope static struct sched_param usage 2011-01-07 15:55:45 +01:00
trace_stack.c llseek: automatically add .llseek fop 2010-10-15 15:53:27 +02:00
trace_stat.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
trace_stat.h tracing/stat: Add stat_release() callback 2009-07-10 12:14:05 +02:00
trace_syscalls.c tracing: Replace syscall_meta_data struct array with pointer array 2011-02-03 09:29:06 -05:00
trace_workqueue.c jump label: Initialize workqueue tracepoints *before* they are registered 2010-09-22 16:30:03 -04:00
trace.c tracing: Fix preempt count leak 2011-01-07 23:20:02 -05:00
trace.h tracing: Make graph related irqs/preemptsoff functions global 2010-10-18 10:53:28 -04:00