diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-06-22 17:16:11 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-06-22 17:16:11 -0700 |
commit | e75c73ad64478c12b3a44b86a3e7f62a4f65b93e (patch) | |
tree | 9dbb1a2a4e53b480df86c49d478751b203cdccd4 /arch/x86/kernel/process.c | |
parent | cfe3eceb7a2eb91284d5605c5315249bb165e9d3 (diff) | |
parent | a8424003679e90b9952e20adcd1ff1560d9dd3e9 (diff) |
Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 FPU updates from Ingo Molnar:
"This tree contains two main changes:
- The big FPU code rewrite: wide reaching cleanups and reorganization
that pulls all the FPU code together into a clean base in
arch/x86/fpu/.
The resulting code is leaner and faster, and much easier to
understand. This enables future work to further simplify the FPU
code (such as removing lazy FPU restores).
By its nature these changes have a substantial regression risk: FPU
code related bugs are long lived, because races are often subtle
and bugs mask as user-space failures that are difficult to track
back to kernel side backs. I'm aware of no unfixed (or even
suspected) FPU related regression so far.
- MPX support rework/fixes. As this is still not a released CPU
feature, there were some buglets in the code - should be much more
robust now (Dave Hansen)"
* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (250 commits)
x86/fpu: Fix double-increment in setup_xstate_features()
x86/mpx: Allow 32-bit binaries on 64-bit kernels again
x86/mpx: Do not count MPX VMAs as neighbors when unmapping
x86/mpx: Rewrite the unmap code
x86/mpx: Support 32-bit binaries on 64-bit kernels
x86/mpx: Use 32-bit-only cmpxchg() for 32-bit apps
x86/mpx: Introduce new 'directory entry' to 'addr' helper function
x86/mpx: Add temporary variable to reduce masking
x86: Make is_64bit_mm() widely available
x86/mpx: Trace allocation of new bounds tables
x86/mpx: Trace the attempts to find bounds tables
x86/mpx: Trace entry to bounds exception paths
x86/mpx: Trace #BR exceptions
x86/mpx: Introduce a boot-time disable flag
x86/mpx: Restrict the mmap() size check to bounds tables
x86/mpx: Remove redundant MPX_BNDCFG_ADDR_MASK
x86/mpx: Clean up the code by not passing a task pointer around when unnecessary
x86/mpx: Use the new get_xsave_field_ptr()API
x86/fpu/xstate: Wrap get_xsave_addr() to make it safer
x86/fpu/xstate: Fix up bad get_xsave_addr() assumptions
...
Diffstat (limited to 'arch/x86/kernel/process.c')
-rw-r--r-- | arch/x86/kernel/process.c | 54 |
1 files changed, 5 insertions, 49 deletions
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index c648139d68d7..9cad694ed7c4 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -25,8 +25,7 @@ #include <asm/idle.h> #include <asm/uaccess.h> #include <asm/mwait.h> -#include <asm/i387.h> -#include <asm/fpu-internal.h> +#include <asm/fpu/internal.h> #include <asm/debugreg.h> #include <asm/nmi.h> #include <asm/tlbflush.h> @@ -76,9 +75,6 @@ void idle_notifier_unregister(struct notifier_block *n) EXPORT_SYMBOL_GPL(idle_notifier_unregister); #endif -struct kmem_cache *task_xstate_cachep; -EXPORT_SYMBOL_GPL(task_xstate_cachep); - /* * this gets called so that we can store lazy state into memory and copy the * current task into the new thread. @@ -87,36 +83,7 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) { *dst = *src; - dst->thread.fpu_counter = 0; - dst->thread.fpu.has_fpu = 0; - dst->thread.fpu.state = NULL; - task_disable_lazy_fpu_restore(dst); - if (tsk_used_math(src)) { - int err = fpu_alloc(&dst->thread.fpu); - if (err) - return err; - fpu_copy(dst, src); - } - return 0; -} - -void free_thread_xstate(struct task_struct *tsk) -{ - fpu_free(&tsk->thread.fpu); -} - -void arch_release_task_struct(struct task_struct *tsk) -{ - free_thread_xstate(tsk); -} - -void arch_task_cache_init(void) -{ - task_xstate_cachep = - kmem_cache_create("task_xstate", xstate_size, - __alignof__(union thread_xstate), - SLAB_PANIC | SLAB_NOTRACK, NULL); - setup_xstate_comp(); + return fpu__copy(&dst->thread.fpu, &src->thread.fpu); } /* @@ -127,6 +94,7 @@ void exit_thread(void) struct task_struct *me = current; struct thread_struct *t = &me->thread; unsigned long *bp = t->io_bitmap_ptr; + struct fpu *fpu = &t->fpu; if (bp) { struct tss_struct *tss = &per_cpu(cpu_tss, get_cpu()); @@ -142,7 +110,7 @@ void exit_thread(void) kfree(bp); } - drop_fpu(me); + fpu__drop(fpu); } void flush_thread(void) @@ -152,19 +120,7 @@ void flush_thread(void) flush_ptrace_hw_breakpoint(tsk); memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array)); - if (!use_eager_fpu()) { - /* FPU state will be reallocated lazily at the first use. */ - drop_fpu(tsk); - free_thread_xstate(tsk); - } else { - if (!tsk_used_math(tsk)) { - /* kthread execs. TODO: cleanup this horror. */ - if (WARN_ON(init_fpu(tsk))) - force_sig(SIGKILL, tsk); - user_fpu_begin(); - } - restore_init_xstate(); - } + fpu__clear(&tsk->thread.fpu); } static void hard_disable_TSC(void) |