]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
ARC: dw2 unwind: enable cfi pseudo ops in string lib
authorVineet Gupta <vgupta@synopsys.com>
Mon, 19 Sep 2016 23:42:25 +0000 (16:42 -0700)
committerVineet Gupta <vgupta@synopsys.com>
Fri, 30 Sep 2016 21:48:22 +0000 (14:48 -0700)
commit86effd0dc675c36caed7b954d7f4f63b77c353b5
tree618b2e5e1bed7286aead4cb7c4fe83157bdb583c
parent5a205a32ffccf6e720a2d2b3aee44b16619016a6
ARC: dw2 unwind: enable cfi pseudo ops in string lib

This uses a new set of annoations viz. ENTRY_CFI/END_CFI to enabel cfi
ops generation.

Note that we didn't change the normal ENTRY/EXIT as we don't actually
want unwind info in the trap/exception/interrutp handlers which use
these, as unwinder then gets confused (it keeps recursing vs. stopping).
Semantically these are leaf routines and unwinding should stop when it
hits those routines.

Before
------

    28.52%     1.19%          9929  hackbench  libuClibc-1.0.17.so   [.] __write_nocancel
            |
            ---__write_nocancel
               |--8.95%--EV_Trap
               |           --8.25%--sys_write
               |                     |--3.93%--sock_write_iter
     ...
               |--2.62%--memset   <==== [LEAF entry as no unwind info]
                         ^^^^^^

After
-----

    29.46%     1.24%         13622  hackbench  libuClibc-1.0.17.so   [.] __write_nocancel
            |
            ---__write_nocancel
               |--9.31%--EV_Trap
               |           --8.62%--sys_write
               |                     |--4.17%--sock_write_iter
     ...
               |--6.19%--sys_write
               |           --6.19%--sock_write_iter
               |                     unix_stream_sendmsg
               |                     |--1.62%--sock_alloc_send_pskb
               |                     |--0.89%--sock_def_readable
               |                     |--0.88%--_raw_spin_unlock_irqrestore
               |                     |--0.69%--memset
               |                     |         ^^^^^^     <==== [now in proper callframe]
               |                     |
               |                      --0.52%--skb_copy_datagram_from_iter

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
arch/arc/kernel/ctx_sw_asm.S
arch/arc/lib/memcmp.S
arch/arc/lib/memcpy-700.S
arch/arc/lib/memcpy-archs.S
arch/arc/lib/memset-archs.S
arch/arc/lib/memset.S
arch/arc/lib/strchr-700.S
arch/arc/lib/strcmp-archs.S
arch/arc/lib/strcmp.S
arch/arc/lib/strcpy-700.S
arch/arc/lib/strlen.S