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86effd0dc6
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
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---__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>
60 lines
1.2 KiB
ArmAsm
60 lines
1.2 KiB
ArmAsm
/*
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* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/linkage.h>
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#define SMALL 7 /* Must be at least 6 to deal with alignment/loop issues. */
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ENTRY_CFI(memset)
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mov_s r4,r0
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or r12,r0,r2
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bmsk.f r12,r12,1
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extb_s r1,r1
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asl r3,r1,8
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beq.d .Laligned
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or_s r1,r1,r3
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brls r2,SMALL,.Ltiny
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add r3,r2,r0
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stb r1,[r3,-1]
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bclr_s r3,r3,0
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stw r1,[r3,-2]
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bmsk.f r12,r0,1
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add_s r2,r2,r12
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sub.ne r2,r2,4
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stb.ab r1,[r4,1]
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and r4,r4,-2
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stw.ab r1,[r4,2]
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and r4,r4,-4
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.Laligned: ; This code address should be aligned for speed.
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asl r3,r1,16
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lsr.f lp_count,r2,2
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or_s r1,r1,r3
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lpne .Loop_end
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st.ab r1,[r4,4]
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.Loop_end:
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j_s [blink]
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.balign 4
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.Ltiny:
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mov.f lp_count,r2
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lpne .Ltiny_end
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stb.ab r1,[r4,1]
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.Ltiny_end:
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j_s [blink]
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END_CFI(memset)
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; memzero: @r0 = mem, @r1 = size_t
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; memset: @r0 = mem, @r1 = char, @r2 = size_t
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ENTRY_CFI(memzero)
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; adjust bzero args to memset args
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mov r2, r1
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mov r1, 0
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b memset ;tail call so need to tinker with blink
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END_CFI(memzero)
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