Re: [PATCH] powerpc/vdso32: inline __get_datapage()

2019-08-20 Thread Benjamin Herrenschmidt
On Fri, 2019-08-16 at 14:48 +, Christophe Leroy wrote: > __get_datapage() is only a few instructions to retrieve the > address of the page where the kernel stores data to the VDSO. > > By inlining this function into its users, a bl/blr pair and > a mflr/mtlr pair is avoided, plus a few reg

[PATCH] powerpc/vdso32: inline __get_datapage()

2019-08-16 Thread Christophe Leroy
__get_datapage() is only a few instructions to retrieve the address of the page where the kernel stores data to the VDSO. By inlining this function into its users, a bl/blr pair and a mflr/mtlr pair is avoided, plus a few reg moves. The improvement is noticeable (about 55 nsec/call on an 8xx)