Steven Rostedt b000c8065a tracing: Remove the extra 4 bytes of padding in events ... Due to a userspace issue with PowerTop v2beta, which hardcoded the offset of event fields that it was using, it broke when we removed the Big Kernel Lock counter from the event header. (commit e6e1e2593 "tracing: Remove lock_depth from event entry") Because this broke userspace, it was determined that we must keep those 4 bytes around. (commit a3a4a5acd "Regression: partial revert "tracing: Remove lock_depth from event entry"") This unfortunately wastes space in the ring buffer. 4 bytes per event, where a lot of events are just 24 bytes. That's 16% of the buffer wasted. A million events will add 4 megs of white space into the buffer. It was later noticed that PowerTop v2beta could not work on systems where the kernel was 64 bit but the userspace was 32 bits. The reason was because the offsets are different between the two and the hard coded offset of one would not work with the other. With PowerTop v2 final, it implemented the same interface that both perf and trace-cmd use. That is, it reads the format file of the event to find the offsets of the fields it needs. This fixes the problem with running powertop on a 32 bit userspace running on a 64 bit kernel. It also no longer requires the 4 byte padding. As PowerTop v2 has been out for a while, and is included in all major distributions, it is time that we can safely remove the 4 bytes of padding. Users of PowerTop v2beta should upgrade to PowerTop v2 final. Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>		2013-01-21 21:05:41 -05:00
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acpi	PCI changes for the v3.8 merge window:	2012-12-13 12:14:47 -08:00
asm-generic	mm: limit mmu_gather batching to fix soft lockups on !CONFIG_PREEMPT	2013-01-04 16:11:46 -08:00
clocksource	…
crypto	…
drm	Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel	2013-01-11 07:52:48 +10:00
keys	…
linux	tracing: Remove the extra 4 bytes of padding in events	2013-01-21 21:05:41 -05:00
math-emu	…
media	…
memory	…
misc	…
net	Merge branch 'master' of git://1984.lsi.us.es/nf	2012-12-28 14:28:17 -08:00
pcmcia	…
ras	…
rdma	UAPI: Remove empty Kbuild files	2013-01-02 17:36:10 -08:00
rxrpc	…
scsi	SCSI misc on 20121212	2012-12-13 19:20:31 -08:00
sound	Merge remote-tracking branch 'asoc/fix/cs4271' into tmp	2013-01-10 12:22:11 +00:00
target	target: Introduce TCM_NO_SENSE	2013-01-10 20:06:08 -08:00
trace	Various bug fixes for ext4. Perhaps the most serious bug fixed is one	2013-01-02 09:57:34 -08:00
uapi	linux/audit.h: move ptrace.h include to kernel header	2013-01-11 14:54:56 -08:00
video	Merge branch 'omap-for-v3.8/fixes-for-merge-window' into omap-for-v3.8/fixes-for-merge-window-v2	2012-12-16 11:28:10 -08:00
xen	Bugfixes:	2012-12-18 12:26:54 -08:00
Kbuild	UAPI: Remove empty Kbuild files	2013-01-02 17:36:10 -08:00