From: Adhemerval Zanella Date: Mon, 22 Apr 2013 09:29:33 +0000 (+0000) Subject: powerpc: Add VDSO version of time X-Git-Tag: omap-for-v3.10/dt-fixes-for-merge-window~66^2~76 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fcb41a2030abe0eb716ef0798035ef9562097f42;p=pandora-kernel.git powerpc: Add VDSO version of time On 04/18/2013 07:38 PM, Anton Blanchard wrote: > Since you are only reading one long you shouldn't need to check the > update count and loop, you will always see a consistent value. The > system call version of time() just does an unprotected load for example. Fixed. > With the above change and with Michael's comments covered (decent > changelog entry and Signed-off-by): > > Acked-by: Anton Blanchard Thanks for the review, below the updated patch: From: Adhemerval Zanella This patch implement the time syscall as vDSO. The performance speedups are: Baseline PPC32: 380 nsec Baseline PPC64: 350 nsec vdso PPC32: 20 nsec vsdo PPC64: 20 nsec Tested on 64 bit build with both 32 bit and 64 bit userland. Acked-by: Anton Blanchard Signed-off-by: Adhemerval Zanella Signed-off-by: Benjamin Herrenschmidt --- Reading git-diff-tree failed