Commit Graph

31 Commits

Author SHA1 Message Date
Ingo Molnar
4f83634710 x86/fpu: Rename fpu_save_init() to copy_fpregs_to_fpstate()
So fpu_save_init() is a historic name that got its name when the only
way the FPU state was FNSAVE, which cleared (well, destroyed) the FPU
state after saving it.

Nowadays the name is misleading, because ever since the introduction of
FXSAVE (and more modern FPU saving instructions) the 'we need to reload
the FPU state' part is only true if there's a pending FPU exception [*],
which is almost never the case.

So rename it to copy_fpregs_to_fpstate() to make it clear what's
happening. Also add a few comments about why we cannot keep registers
in certain cases.

Also clean up the control flow a bit, to make it more apparent when
we are dropping/keeping FP registers, and to optimize the common
case (of keeping fpregs) some more.

[*] Probably not true anymore, modern instructions always leave the FPU
    state intact, even if exceptions are pending: because pending FP
    exceptions are posted on the next FP instruction, not asynchronously.

    They were truly asynchronous back in the IRQ13 case, and we had to
    synchronize with them, but that code is not working anymore: we don't
    have IRQ13 mapped in the IDT anymore.

    But a cleanup patch is obviously not the place to change subtle behavior.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:49 +02:00
Ingo Molnar
910665882f x86/fpu: Uninline the irq_ts_save()/restore() functions
Especially the irq_ts_save() function is pretty bloaty, generating
over a dozen instructions, so uninline them.

Even though the API is used rarely, the space savings are measurable:

   text    data     bss     dec     hex filename
   13331995        2572920 1634304 17539219        10ba093 vmlinux.before
   13331739        2572920 1634304 17538963        10b9f93 vmlinux.after

( This also allows the removal of an include file inclusion from fpu/api.h,
  speeding up the kernel build slightly. )

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:48 +02:00
Ingo Molnar
952f07ecbd x86/fpu: Move various internal function prototypes to fpu/internal.h
There are a number of FPU internal function prototypes and an inline function
in fpu/api.h, mostly placed so historically as the code grew over the years.

Move them over into fpu/internal.h where they belong. (Add sched.h include
to stackprotector.h which incorrectly relied on getting it from fpu/api.h.)

fpu/api.h is now a pure file that only contains FPU APIs intended for driver
use.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:48 +02:00
Ingo Molnar
d63e79b114 x86/fpu: Uninline kernel_fpu_begin()/end()
Both inline functions call an inline function unconditionally, so we
already pay the function call based clobbering cost. Uninline them.

This saves quite a bit of code in various performance sensitive
code paths:

   text            data    bss     dec             hex     filename
   13321334        2569888 1634304 17525526        10b6b16 vmlinux.before
   13320246        2569888 1634304 17524438        10b66d6 vmlinux.after

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:48 +02:00
Ingo Molnar
e229537543 x86/fpu: Move fpu__save() to fpu/internals.h
It's an internal method, not a driver API, so move it from fpu/api.h
to fpu/internal.h.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:48 +02:00
Ingo Molnar
dd863880ac x86/fpu: Move fpu__init_system_early_generic() out of fpu__detect()
Move the fpu__init_system_early_generic() call into fpu__init_system(),
which hosts all the system init calls.

Expose fpu__init_system() to other modules - this will be our main and only
system init function.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:46 +02:00
Ingo Molnar
21c4cd108a x86/fpu: Simplify fpu__cpu_init()
After the latest round of cleanups, fpu__cpu_init() has become
a simple call to fpu__init_cpu().

Rename fpu__init_cpu() to fpu__cpu_init() and remove the
extra layer.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:44 +02:00
Ingo Molnar
c42103b226 x86/fpu: Remove xsave_init()
Expand fpu__init_system_xstate() and fpu__init_cpu_xstate() calls
into xsave_init() calls.

(This will allow us to call the proper versions in higher level FPU init code
later on.)

No change in functionality.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:40 +02:00
Ingo Molnar
55cc4678b7 x86/fpu: Make the system/cpu init distinction clear in the xstate code as well
Rename existing xstate init functions along the system/cpu init principles:

	fpu__init_system_xstate(): called once per system bootup
	fpu__init_cpu_xstate():    called per CPU onlining

Also make the fpu__init_cpu_xstate() early code invariant:
if xfeatures_mask is not set yet then don't crash but return.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:39 +02:00
Ingo Molnar
3e5e126774 x86/fpu: Remove 'init_xstate_buf' bootmem allocation
Make init_xstate_buf allocated statically at build time.

This structure's maximum size is around 1KB - and it's allocated even on
most modern embedded x86 CPUs which strive for FPU instruction set parity
with desktop and server CPUs, so it's not like we can save much on smaller
systems.

This removes the last bootmem allocation from the FPU init path, allowing
it to be called earlier in the boot sequence.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:39 +02:00
Ingo Molnar
966ece619e x86/fpu: Remove xsave_init() bootmem allocations
There's only 8 xstate bits at the moment, and it's not like we
can support unknown bits - so put xstate_offsets[] and
xstate_sizes[] into static allocation.

This is in preparation to be able to call the FPU init code
earlier, when there's no bootmem available yet.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:38 +02:00
Ingo Molnar
66af8e2764 x86/fpu: Rename __thread_fpu_end() to fpregs_deactivate()
Propagate the 'fpu->fpregs_active' naming to the high level function that
clears it.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:37 +02:00
Ingo Molnar
232f62cdd7 x86/fpu: Rename __thread_fpu_begin() to fpregs_activate()
Propagate the 'fpu->fpregs_active' naming to the high level
function that sets it.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:37 +02:00
Ingo Molnar
723c58e428 x86/fpu: Rename __thread_clear_has_fpu() to __fpregs_deactivate()
Propagate the 'fpu->fpregs_active' naming to the functions that
clears it.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:37 +02:00
Ingo Molnar
dfaea4e6a2 x86/fpu: Rename __thread_set_has_fpu() to __fpregs_activate()
Propagate the 'fpu->fpregs_active' naming to the functions that
sets it.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:36 +02:00
Ingo Molnar
d5cea9b0af x86/fpu: Rename fpu->has_fpu to fpu->fpregs_active
So the current code uses fpu->has_cpu to determine whether a given
user FPU context is actively loaded into the FPU's registers [*] and
that those registers represent the task's current FPU state.

But this term is not unambiguous: especially the distinction between
fpu->has_fpu, PF_USED_MATH and fpu_fpregs_owner_ctx is not clear.

Increase clarity by unambigously signalling that it's about
hardware registers being active right now, by renaming it to
fpu->fpregs_active.

( In later patches we'll use more of the 'fpregs' naming, which will
  make it easier to grep for as well. )

[*] There's the kernel_fpu_begin()/end() primitive that also
    activates FPU hw registers as well and uses them, without
    touching the fpu->fpregs_active flag.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:36 +02:00
Ingo Molnar
e783e8167d x86/fpu: Explain the AVX register layout in the xsave area
The previous explanation was rather cryptic.

Also transform "u32 [64]" to the more readable "u8[256]" form.

No change in implementation.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:35 +02:00
Ingo Molnar
678eaf6034 x86/fpu: Rename regset FPU register accessors
Rename regset accessors to prefix them with 'regset_', because we
want to start using the 'fpregs_active' name elsewhere.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:35 +02:00
Ingo Molnar
400e4b2091 x86/fpu: Rename xsave.header::xstate_bv to 'xfeatures'
'xsave.header::xstate_bv' is a misnomer - what does 'bv' stand for?

It probably comes from the 'XGETBV' instruction name, but I could
not find in the Intel documentation where that abbreviation comes
from. It could mean 'bit vector' - or something else?

But how about - instead of guessing about a weird name - we named
the field in an obvious and descriptive way that tells us exactly
what it does?

So rename it to 'xfeatures', which is a bitmask of the
xfeatures that are fpstate_active in that context structure.

Eyesore like:

           fpu->state->xsave.xsave_hdr.xstate_bv |= XSTATE_FP;

is now much more readable:

           fpu->state->xsave.header.xfeatures |= XSTATE_FP;

Which form is not just infinitely more readable, but is also
shorter as well.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:35 +02:00
Ingo Molnar
3a54450b5e x86/fpu: Rename 'xsave_hdr' to 'header'
Code like:

           fpu->state->xsave.xsave_hdr.xstate_bv |= XSTATE_FP;

is an eyesore, because not only is the words 'xsave' and 'state'
are repeated twice times (!), but also because of the 'hdr' and 'bv'
abbreviations that are pretty meaningless at a first glance.

Start cleaning this up by renaming 'xsave_hdr' to 'header'.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:34 +02:00
Ingo Molnar
9254aaa0fe x86/fpu: Move XCR0 manipulation to the FPU code proper
The suspend code accesses FPU state internals, add a helper for
it and isolate it.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:33 +02:00
Ingo Molnar
614df7fb8a x86/fpu: Rename 'pcntxt_mask' to 'xfeatures_mask'
So the 'pcntxt_mask' is a misnomer, it's essentially meaningless to anyone
who doesn't know what it does exactly.

Name it more descriptively as 'xfeatures_mask'.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:33 +02:00
Ingo Molnar
7b302e6731 x86/fpu: Remove assembly guard from asm/fpu/api.h
asm/fpu/api.h does not contain any defines useful to assembly code,
and no assembly code includes asm/fpu/api.h. Remove the historic
 #ifndef __ASSEMBLY__ leftover guard.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:32 +02:00
Ingo Molnar
df6397525c x86/fpu: Move MXCSR_DEFAULT to fpu/internal.h
fpu/types.h gets included everywhere, move the MXCSR_DEFAULT to
fpu/internal.h, the place where it's used.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:31 +02:00
Ingo Molnar
78f7f1e54b x86/fpu: Rename fpu-internal.h to fpu/internal.h
This unifies all the FPU related header files under a unified, hiearchical
naming scheme:

 - asm/fpu/types.h:      FPU related data types, needed for 'struct task_struct',
                         widely included in almost all kernel code, and hence kept
                         as small as possible.

 - asm/fpu/api.h:        FPU related 'public' methods exported to other subsystems.

 - asm/fpu/internal.h:   FPU subsystem internal methods

 - asm/fpu/xsave.h:      XSAVE support internal methods

(Also standardize the header guard in asm/fpu/internal.h.)

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:31 +02:00
Ingo Molnar
a137fb6bbf x86/fpu: Move xsave.h to fpu/xsave.h
Move the xsave.h header file to the FPU directory as well.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:30 +02:00
Ingo Molnar
df6b35f409 x86/fpu: Rename i387.h to fpu/api.h
We already have fpu/types.h, move i387.h to fpu/api.h.

The file name has become a misnomer anyway: it offers generic FPU APIs,
but is not limited to i387 functionality.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:30 +02:00
Ingo Molnar
eb6a3251bf x86/fpu: Remove task_disable_lazy_fpu_restore()
Replace task_disable_lazy_fpu_restore() with easier to read
open-coded uses: we already update the fpu->last_cpu field
explicitly in other cases.

(This also removes yet another task_struct using FPU method.)

Better explain the fpu::last_cpu field in the structure definition.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:26 +02:00
Ingo Molnar
c5bedc6847 x86/fpu: Get rid of PF_USED_MATH usage, convert it to fpu->fpstate_active
Introduce a simple fpu->fpstate_active flag in the fpu context data structure
and use that instead of PF_USED_MATH in task->flags.

Testing for this flag byte should be slightly more efficient than
testing a bit in a bitmask, but the main advantage is that most
FPU functions can now be performed on a 'struct fpu' alone, they
don't need access to 'struct task_struct' anymore.

There's a slight linecount increase, mostly due to the 'fpu' local
variables and due to extra comments. The local variables will go away
once we move most of the FPU methods to pure 'struct fpu' parameters.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:25 +02:00
Ingo Molnar
47bc510634 x86/fpu: Clean up asm/fpu/types.h
- add header guards

 - standardize vertical alignment

 - add comments about MPX

No code changed.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:15 +02:00
Ingo Molnar
14b9675ae9 x86/fpu: Move FPU data structures to asm/fpu_types.h
Move the FPU details to asm/fpu_types.h, to further factor out the
FPU code.

( As an added bonus, the 'struct orig_ist' definition now moves
  next to its other data types - the FPU definitions were
  slapped in the middle of them for some mysterious reason. )

No code changed.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:15 +02:00