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2d04864247
linux/arch/arc
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Vineet Gupta 2d04864247 ARC: dw2 unwind: don't force dwarf 2 
In .debug_frame based unwinding regime, we used to force -gdwarf-2 since
kernel unwinder only claimed to handle dwarf 2. This changed since commit
6d0d506012 ("ARC: dw2 unwind: Don't bail for CIE.version != 1")
which added some support beyond dwarf 2, atleast to handle CIE != 1

The ill-effect of -gdwarf-2 is that it forces generation of .debug_*
sections, which bloats loadable modules .ko files. For the curious, this
doesn't affect vmlinx binary since linker script discards .debug_* but
same discard is not yet implemented for modules.

So it seems we can drop the -gdwarf-2 toggle, which should not be needed
anyways given that we now use .eh_frame based unwinding.

I've verified using GNU 2016.09-engo10 that the actual unwind info is
not different with or w/o this toggle - but the debug_* sections are
gone for good.

before
-----
arc-linux-readelf -S q_proc.ko-unwinding-1-eh_frame-switch | grep debug
  [15] .debug_info       PROGBITS        00000000 000300 00d08d 00 	0   0  1
  [16] .rela.debug_info  RELA            00000000 0162a0 008844 0c   I 29  15  4
  [17] .debug_abbrev     PROGBITS        00000000 00d38d 0005f8 00 	0   0  1
  [18] .debug_loc        PROGBITS        00000000 00d985 000070 00 	0   0  1
  [19] .rela.debug_loc   RELA            00000000 01eae4 0000c0 0c   I 29  18  4
  [20] .debug_aranges    PROGBITS        00000000 00d9f5 000040 00 	0   0  1
  [21] .rela.debug_arang RELA            00000000 01eba4 000030 0c   I 29  20  4
  [22] .debug_ranges     PROGBITS        00000000 00da35 000018 00 	0   0  1
  [23] .rela.debug_range RELA            00000000 01ebd4 000030 0c   I 29  22  4
  [24] .debug_line       PROGBITS        00000000 00da4d 000b5b 00 	0   0  1
  [25] .rela.debug_line  RELA            00000000 01ec04 0000cc 0c   I 29  24  4
  [26] .debug_str        PROGBITS        00000000 00e5a8 007831 01   MS 0   0  1

after
----

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-30 14:48:21 -07:00
..
boot ARCv2: Add support for ZeBu Emulation platform for HS cores 2016-09-30 14:48:15 -07:00
configs ARCv2: Add support for ZeBu Emulation platform for HS cores 2016-09-30 14:48:15 -07:00
include ARC: module: support R_ARC_32_PCREL relocation 2016-09-30 14:48:19 -07:00
kernel ARC: dw2 unwind: switch to .eh_frame based unwinding 2016-09-30 14:48:20 -07:00
lib ARCv2: lib: memcpy: use local symbols 2015-11-03 17:33:00 +05:30
mm ARCv2: Support dynamic peripheral address space in HS38 rel 3.0 cores 2016-09-30 14:48:17 -07:00
oprofile ARC: OProfile support 2013-02-15 23:16:00 +05:30
plat-axs10x ARC updates for 4.7-rc1 2016-05-19 09:46:18 -07:00
plat-eznps ARC: [plat-eznps] Use dedicated identity auxiliary register. 2016-05-09 09:32:33 +05:30
plat-sim ARCv2: Add support for ZeBu Emulation platform for HS cores 2016-09-30 14:48:15 -07:00
plat-tb10x arc: select GPIOLIB directly 2016-04-26 14:07:59 +02:00
Kbuild
Kconfig ARCv2: Implement atomic64 based on LLOCKD/SCONDD instructions 2016-09-30 14:48:17 -07:00
Kconfig.debug ARC: With earlycon in use, retire EARLY_PRINTK 2015-05-11 11:20:21 +05:30
Makefile ARC: dw2 unwind: don't force dwarf 2 2016-09-30 14:48:21 -07:00