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authorLinus Torvalds <torvalds@linux-foundation.org>2019-03-07 17:09:28 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-03-07 17:09:28 -0800
commit35a738fb5fd0fdd1cc7e749e3a45f1876ecd1db8 (patch)
tree521ca17847cda293b4a67d95fb6298b78bae75a2 /arch/x86/include/asm
parentbcd49c3dd172c38e14faf151adca63c8db4c9557 (diff)
parent2f7726f955572e587d5f50fbe9b2deed5334bd90 (diff)
downloadlinux-0-day-35a738fb5fd0fdd1cc7e749e3a45f1876ecd1db8.tar.gz
linux-0-day-35a738fb5fd0fdd1cc7e749e3a45f1876ecd1db8.tar.xz
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: "Three changes: - preparatory patch for AVX state tracking that computing-cluster folks would like to use for user-space batching - but we are not happy about the related ABI yet so this is only the kernel tracking side - a cleanup for CR0 handling in do_device_not_available() - plus we removed a workaround for an ancient binutils version" * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/fpu: Track AVX-512 usage of tasks x86/fpu: Get rid of CONFIG_AS_FXSAVEQ x86/traps: Have read_cr0() only once in the #NM handler
Diffstat (limited to 'arch/x86/include/asm')
-rw-r--r--arch/x86/include/asm/fpu/internal.h57
-rw-r--r--arch/x86/include/asm/fpu/types.h7
2 files changed, 20 insertions, 44 deletions
diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h
index fa2c93cb42a2..fb04a3ded7dd 100644
--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -137,37 +137,25 @@ static inline int copy_fxregs_to_user(struct fxregs_state __user *fx)
{
if (IS_ENABLED(CONFIG_X86_32))
return user_insn(fxsave %[fx], [fx] "=m" (*fx), "m" (*fx));
- else if (IS_ENABLED(CONFIG_AS_FXSAVEQ))
+ else
return user_insn(fxsaveq %[fx], [fx] "=m" (*fx), "m" (*fx));
- /* See comment in copy_fxregs_to_kernel() below. */
- return user_insn(rex64/fxsave (%[fx]), "=m" (*fx), [fx] "R" (fx));
}
static inline void copy_kernel_to_fxregs(struct fxregs_state *fx)
{
- if (IS_ENABLED(CONFIG_X86_32)) {
+ if (IS_ENABLED(CONFIG_X86_32))
kernel_insn(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx));
- } else {
- if (IS_ENABLED(CONFIG_AS_FXSAVEQ)) {
- kernel_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx));
- } else {
- /* See comment in copy_fxregs_to_kernel() below. */
- kernel_insn(rex64/fxrstor (%[fx]), "=m" (*fx), [fx] "R" (fx), "m" (*fx));
- }
- }
+ else
+ kernel_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx));
}
static inline int copy_user_to_fxregs(struct fxregs_state __user *fx)
{
if (IS_ENABLED(CONFIG_X86_32))
return user_insn(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx));
- else if (IS_ENABLED(CONFIG_AS_FXSAVEQ))
+ else
return user_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx));
-
- /* See comment in copy_fxregs_to_kernel() below. */
- return user_insn(rex64/fxrstor (%[fx]), "=m" (*fx), [fx] "R" (fx),
- "m" (*fx));
}
static inline void copy_kernel_to_fregs(struct fregs_state *fx)
@@ -184,34 +172,8 @@ static inline void copy_fxregs_to_kernel(struct fpu *fpu)
{
if (IS_ENABLED(CONFIG_X86_32))
asm volatile( "fxsave %[fx]" : [fx] "=m" (fpu->state.fxsave));
- else if (IS_ENABLED(CONFIG_AS_FXSAVEQ))
+ else
asm volatile("fxsaveq %[fx]" : [fx] "=m" (fpu->state.fxsave));
- else {
- /* Using "rex64; fxsave %0" is broken because, if the memory
- * operand uses any extended registers for addressing, a second
- * REX prefix will be generated (to the assembler, rex64
- * followed by semicolon is a separate instruction), and hence
- * the 64-bitness is lost.
- *
- * Using "fxsaveq %0" would be the ideal choice, but is only
- * supported starting with gas 2.16.
- *
- * Using, as a workaround, the properly prefixed form below
- * isn't accepted by any binutils version so far released,
- * complaining that the same type of prefix is used twice if
- * an extended register is needed for addressing (fix submitted
- * to mainline 2005-11-21).
- *
- * asm volatile("rex64/fxsave %0" : "=m" (fpu->state.fxsave));
- *
- * This, however, we can work around by forcing the compiler to
- * select an addressing mode that doesn't require extended
- * registers.
- */
- asm volatile( "rex64/fxsave (%[fx])"
- : "=m" (fpu->state.fxsave)
- : [fx] "R" (&fpu->state.fxsave));
- }
}
/* These macros all use (%edi)/(%rdi) as the single memory argument. */
@@ -414,6 +376,13 @@ static inline int copy_fpregs_to_fpstate(struct fpu *fpu)
{
if (likely(use_xsave())) {
copy_xregs_to_kernel(&fpu->state.xsave);
+
+ /*
+ * AVX512 state is tracked here because its use is
+ * known to slow the max clock speed of the core.
+ */
+ if (fpu->state.xsave.header.xfeatures & XFEATURE_MASK_AVX512)
+ fpu->avx512_timestamp = jiffies;
return 1;
}
diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h
index 202c53918ecf..2e32e178e064 100644
--- a/arch/x86/include/asm/fpu/types.h
+++ b/arch/x86/include/asm/fpu/types.h
@@ -303,6 +303,13 @@ struct fpu {
unsigned char initialized;
/*
+ * @avx512_timestamp:
+ *
+ * Records the timestamp of AVX512 use during last context switch.
+ */
+ unsigned long avx512_timestamp;
+
+ /*
* @state:
*
* In-memory copy of all FPU registers that we save/restore