mirror of
https://github.com/torvalds/linux.git
synced 2025-11-04 10:40:15 +02:00
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
|
---__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>
78 lines
1.3 KiB
ArmAsm
78 lines
1.3 KiB
ArmAsm
/*
|
|
* Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
|
|
ENTRY_CFI(strcmp)
|
|
or r2, r0, r1
|
|
bmsk_s r2, r2, 1
|
|
brne r2, 0, @.Lcharloop
|
|
|
|
;;; s1 and s2 are word aligned
|
|
ld.ab r2, [r0, 4]
|
|
|
|
mov_s r12, 0x01010101
|
|
ror r11, r12
|
|
.align 4
|
|
.LwordLoop:
|
|
ld.ab r3, [r1, 4]
|
|
;; Detect NULL char in str1
|
|
sub r4, r2, r12
|
|
ld.ab r5, [r0, 4]
|
|
bic r4, r4, r2
|
|
and r4, r4, r11
|
|
brne.d.nt r4, 0, .LfoundNULL
|
|
;; Check if the read locations are the same
|
|
cmp r2, r3
|
|
beq.d .LwordLoop
|
|
mov.eq r2, r5
|
|
|
|
;; A match is found, spot it out
|
|
#ifdef __LITTLE_ENDIAN__
|
|
swape r3, r3
|
|
mov_s r0, 1
|
|
swape r2, r2
|
|
#else
|
|
mov_s r0, 1
|
|
#endif
|
|
cmp_s r2, r3
|
|
j_s.d [blink]
|
|
bset.lo r0, r0, 31
|
|
|
|
.align 4
|
|
.LfoundNULL:
|
|
#ifdef __BIG_ENDIAN__
|
|
swape r4, r4
|
|
swape r2, r2
|
|
swape r3, r3
|
|
#endif
|
|
;; Find null byte
|
|
ffs r0, r4
|
|
bmsk r2, r2, r0
|
|
bmsk r3, r3, r0
|
|
swape r2, r2
|
|
swape r3, r3
|
|
;; make the return value
|
|
sub.f r0, r2, r3
|
|
mov.hi r0, 1
|
|
j_s.d [blink]
|
|
bset.lo r0, r0, 31
|
|
|
|
.align 4
|
|
.Lcharloop:
|
|
ldb.ab r2, [r0, 1]
|
|
ldb.ab r3, [r1, 1]
|
|
nop
|
|
breq r2, 0, .Lcmpend
|
|
breq r2, r3, .Lcharloop
|
|
|
|
.align 4
|
|
.Lcmpend:
|
|
j_s.d [blink]
|
|
sub r0, r2, r3
|
|
END_CFI(strcmp)
|