Messages in this thread Patch in this message | | | Date | Fri, 06 Feb 2015 11:42:29 -0500 | From | Rik van Riel <> | Subject | Re: [PATCH 4/6] x86,fpu: use disable_task_lazy_fpu_restore helper |
| |
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
On 02/02/2015 02:21 PM, Oleg Nesterov wrote: > I'll try to read this patch tomorrow. Too late for me. > > I think it is fine, but > > On 02/02, riel@redhat.com wrote: >> >> This also fixes the lazy FPU restore disabling in drop_fpu, >> which only really works when !use_eager_fpu(). ... >> >> --- a/arch/x86/include/asm/fpu-internal.h +++ >> b/arch/x86/include/asm/fpu-internal.h @@ -396,7 +396,7 @@ static >> inline void drop_fpu(struct task_struct *tsk) * Forget >> coprocessor state.. */ preempt_disable(); - >> tsk->thread.fpu_counter = 0; + >> task_disable_lazy_fpu_restore(tsk); __drop_fpu(tsk); >> clear_used_math(); > > perhaps this makes sense anyway, but I am not sure if the changelog > is right. > > Note that we clear PF_USED_MATH, last_fpu/has_fpu have no effect > after this.
After a few days on the RCU code, I'm back to this :)
You are right, I should drop the change above from the patch, and disable lazy fpu restore explicitly in places where we need it.
I will send a v2 of these patches, without patch 6/6.
Ingo, would you like me to also re-send Oleg's FPU patches that are not in -tip yet?
- -- All rights reversed -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJU1O71AAoJEM553pKExN6DUtEH/R8X02MHD7GUxO4hyiLECL9f SQDdF1l+1rqcQo7e+5nRJ5/rFvAIaNA5oBMOZJ9MlJRd6HOKS+VqLLpb8idvApeK zRiYUdeyoui3e0po2nNCx/GBfXqMYca+qH4JMMq6gzv0c9Nm9Zq9pbKDbO2znns8 10YQexvZsHUiJgt63YoZSwxFKD1iAhnTOGBhZOJu/s27Qtu+7gyuyIcuMMDFj2eu ACGqZPcjG2u7TlC+D4uivSferMrduNnWsxGq3AY32/nNhjKGmXaFJxRHDdCsYAGJ +S+SFuUWq6JoD7MuC02NQyAs/bQzqhVfn8v7gm2gromqIIQGzBABtI+Em0LGFP4= =3R+T -----END PGP SIGNATURE-----
| |