mirror/glibc
2
0
Fork 0
mirror of git://sourceware.org/git/glibc.git synced 2025-04-12 14:21:18 +08:00
Code Issues Packages Projects Releases Wiki Activity

powerpc: Fix tabort usage in syscalls

Browse Source 
Fix usage of tabort in generated syscalls.  r0 has special meaning
when used with this instruction, thus it will not generate
persistent errors, nor return an error code.  This mitigates poor
CPU usage when performing elided critical sections.

Additionally, transactions should be aborted when entering a user
invoked syscall.  Otherwise the results of the transaction may be
undefined.

2015-08-25  Paul E. Murphy  <murphyp@linux.vnet.ibm.com>

	* sysdeps/powerpc/powerpc32/sysdep.h (ABORT_TRANSACTION): Use
	register other than r0 for tabort, it has special meaning.
	* sysdeps/powerpc/powerpc64/sysdep.h (ABORT_TRANSACTION): Likewise
	* sysdeps/unix.sysv/linux/powerpc/syscall.S (syscall): Abort
	transaction before starting syscall.
This commit is contained in:
Paul E. Murphy 2015-08-21 14:39:01 -05:00 committed by Tulio Magno Quites Machado Filho
parent fe7faec3e5
commit 18173559a2
4 changed files with 13 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
ChangeLog
View File

@ -1,3 +1,11 @@
2015-08-25 Paul E. Murphy <murphyp@linux.vnet.ibm.com>
* sysdeps/powerpc/powerpc32/sysdep.h (ABORT_TRANSACTION): Use
register other than r0 for tabort, it has special meaning.
* sysdeps/powerpc/powerpc64/sysdep.h (ABORT_TRANSACTION): Likewise
* sysdeps/unix.sysv/linux/powerpc/syscall.S (syscall): Abort
transaction before starting syscall.
2015-08-25 Rajalakshmi Srinivasaraghavan <raji@linux.vnet.ibm.com>
* sysdeps/powerpc/powerpc64/power7/strstr.S: Handle worst case.

4
sysdeps/powerpc/powerpc32/sysdep.h
View File

@ -95,8 +95,8 @@ GOT_LABEL: ; \
lwz 0,TM_CAPABLE(2); \
cmpwi 0,0; \
beq 1f; \
li 0,_ABORT_SYSCALL; \
tabort. 0; \
li 11,_ABORT_SYSCALL; \
tabort. 11; \
.align 4; \
1:
#else

4
sysdeps/powerpc/powerpc64/sysdep.h
View File

@ -279,8 +279,8 @@ LT_LABELSUFFIX(name,_name_end): ; \
lwz 0,TM_CAPABLE(13); \
cmpwi 0,0; \
beq 1f; \
li 0,_ABORT_SYSCALL; \
tabort. 0; \
li 11,_ABORT_SYSCALL; \
tabort. 11; \
.align 4; \
1:
#else

1
sysdeps/unix/sysv/linux/powerpc/syscall.S
View File

@ -18,6 +18,7 @@
#include <sysdep.h>
ENTRY (syscall)
ABORT_TRANSACTION
mr r0,r3
mr r3,r4
mr r4,r5