[patch 2/3] x86/fpu: Rename irq_fpu_usable()

Thomas Gleixner
2022-05-01T19:31:56Z

This can be invoked from almost any context, except NMI. The only
requirement is that the context is not migrateable.

Rename it to kernel_fpu_usable().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/um/include/asm/fpu/api.h | 2 +-
arch/x86/include/asm/fpu/api.h | 4 ++--
arch/x86/include/asm/simd.h | 2 +-
arch/x86/kernel/fpu/core.c | 13 +++++++------
net/netfilter/nft_set_pipapo_avx2.c | 2 +-
5 files changed, 12 insertions(+), 11 deletions(-)

--- a/arch/um/include/asm/fpu/api.h
+++ b/arch/um/include/asm/fpu/api.h
@@ -11,7 +11,7 @@
#define kernel_fpu_begin() (void)0
#define kernel_fpu_end() (void)0

-static inline bool irq_fpu_usable(void)
+static inline bool kernel_fpu_usable(void)
{
return true;
}
--- a/arch/x86/include/asm/fpu/api.h
+++ b/arch/x86/include/asm/fpu/api.h
@@ -19,7 +19,7 @@
* disables preemption so be careful if you intend to use it for long periods
* of time.
* If you intend to use the FPU in irq/softirq you need to check first with
- * irq_fpu_usable() if it is possible.
+ * kernel_fpu_usable() if it is possible.
*/

/* Kernel FPU states to initialize in kernel_fpu_begin_mask() */
@@ -28,7 +28,7 @@

extern void kernel_fpu_begin_mask(unsigned int kfpu_mask);
extern void kernel_fpu_end(void);
-extern bool irq_fpu_usable(void);
+extern bool kernel_fpu_usable(void);
extern void fpregs_mark_activate(void);

/* Code that is unaware of kernel_fpu_begin_mask() can use this */
--- a/arch/x86/include/asm/simd.h
+++ b/arch/x86/include/asm/simd.h
@@ -8,5 +8,5 @@
*/
static __must_check inline bool may_use_simd(void)
{
- return irq_fpu_usable();
+ return kernel_fpu_usable();
}
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -49,11 +49,12 @@ static DEFINE_PER_CPU(bool, in_kernel_fp
*/
DEFINE_PER_CPU(struct fpu *, fpu_fpregs_owner_ctx);

-/*
- * Can we use the FPU in kernel mode with the
- * whole "kernel_fpu_begin/end()" sequence?
+/**
+ * kernel_fpu_usable - Check whether kernel FPU usage is possible
+ *
+ * Has to be invoked before calling kernel_fpu_begin().
*/
-bool irq_fpu_usable(void)
+bool kernel_fpu_usable(void)
{
if (WARN_ON_ONCE(in_nmi()))
return false;
@@ -81,7 +82,7 @@ bool irq_fpu_usable(void)
*/
return !softirq_count();
}
-EXPORT_SYMBOL(irq_fpu_usable);
+EXPORT_SYMBOL(kernel_fpu_usable);

/*
* Track AVX512 state use because it is known to slow the max clock
@@ -409,7 +410,7 @@ void kernel_fpu_begin_mask(unsigned int
{
preempt_disable();

- WARN_ON_FPU(!irq_fpu_usable());
+ WARN_ON_FPU(!kernel_fpu_usable());
WARN_ON_FPU(this_cpu_read(in_kernel_fpu));

this_cpu_write(in_kernel_fpu, true);
--- a/net/netfilter/nft_set_pipapo_avx2.c
+++ b/net/netfilter/nft_set_pipapo_avx2.c
@@ -1128,7 +1128,7 @@ bool nft_pipapo_avx2_lookup(const struct
bool map_index;
int i, ret = 0;

- if (unlikely(!irq_fpu_usable()))
+ if (unlikely(!kernel_fpu_usable()))
return nft_pipapo_lookup(net, set, key, ext);

m = rcu_dereference(priv->match);