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| author | Christian Borntraeger <borntraeger@de.ibm.com> | 2017-06-19 10:59:40 +0200 |
|---|---|---|
| committer | Stefan Liebler <stli@linux.vnet.ibm.com> | 2017-06-19 10:59:40 +0200 |
| commit | 35810f5ccf735d8df0a783bc6ed5fbe455e64876 (patch) | |
| tree | ac4dbf1066e2d624fe5bd52bce2c2ebda11fb951 /ChangeLog | |
| parent | 52243b520e2d336431ea410ef3aa1f766642f1d2 (diff) | |
| download | glibc-35810f5ccf735d8df0a783bc6ed5fbe455e64876.tar.gz glibc-35810f5ccf735d8df0a783bc6ed5fbe455e64876.tar.xz glibc-35810f5ccf735d8df0a783bc6ed5fbe455e64876.zip | |
s390: optimize syscall function
Since kernel 2.6.0 all Linux version accept the system call number
in register 1 for svc 0. There is no need to have special handling
that uses EX for system calls < 256. This will simplify and speed
up that code.
A microbenchmark doing "syscall(__NR_getpid);" in a loops gets faster
by ~12%.
* sysdeps/unix/sysv/linux/s390/s390-32/syscall.S: Simplify
code by always using SVC 0 instead of EX.
* sysdeps/unix/sysv/linux/s390/s390-64/syscall.S: Likewise.
Diffstat (limited to 'ChangeLog')
| -rw-r--r-- | ChangeLog | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog index f4ac921321..bf6c25aceb 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2017-06-19 Christian Borntraeger <borntraeger@de.ibm.com> + + * sysdeps/unix/sysv/linux/s390/s390-32/syscall.S (syscall): + Simplify code by always using SVC 0 instead of EX. + * sysdeps/unix/sysv/linux/s390/s390-64/syscall.S: Likewise. + 2017-06-16 H.J. Lu <hongjiu.lu@intel.com> * elf/Versions (ld): Remove _dl_out_of_memory. |