-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 02/02/2015 01:55 PM, Oleg Nesterov wrote: > On 02/02, r...@redhat.com wrote: >> >> From: Rik van Riel <r...@redhat.com> >> >> With Oleg's patch "x86, fpu: don't abuse FPU in kernel threads >> if use_eager_fpu()", kernel threads no longer have an FPU state >> even on systems with use_eager_fpu() >> >> That in turn means that a task may still have its FPU state >> loaded in the FPU registers, if the task only got interrupted by >> kernel threads from when it went to sleep, to when it woke up >> again. >> >> In that case, there is no need to restore the FPU state for this >> task, since it is still in the registers. >> >> The kernel can simply use the same logic to determine this as is >> used for !use_eager_fpu() systems. > > Yes, agreed, I was going to do this too. > > And in fact this change make sense even without "don't abuse FPU in > kernel threads", I think. > > But in theory it depends on another change, "__kernel_fpu_begin() > should clear fpu_owner_task even if use_eager_fpu()". > > And that series was ignored ;) > > I think this patch is fine.
Ingo, does the FPU code have a sub-maintainer, or should all the FPU patches go straight through you? Would it be better for you if FPU patches came through a git tree you could just pull? - -- All rights reversed -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJUz83HAAoJEM553pKExN6DqrQH/iP5cfUUtIqguM4oS19WO33Y 5H/wdjVIGOJw4Rt7U+550Y9m5VMXsuQrO17PagjZGsxbSm9QQhA6esVMDvXfOFH1 taWW1tFog4VTMueNYbOC5asqsicTrhNqfiLQFM9CmJFGOPO4lDQ9n+OPS64CkQ/d onylevtR4UWjggpEdkoOlmvbQH8RhnaC4JWKSXxP06YBakfP41gIMMfAjFNMP9O4 b/r1nU/WBQsTSX7pzQMnEx/Igp9LkT+X0Y93NerF/0O7gic9Wv7tKTEaUa3DzS7p U7xgT8xX88AJ6QQGQfB3IQSkjcb3N9UCY1CYkkWqigm9MhhlLxPyRDAy7vkrUlk= =j/eO -----END PGP SIGNATURE----- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
