nixpkgs/pkgs/os-specific/linux/kernel/export_kernel_fpu_functions.patch
Jörg Thalheim 7b77c27caa
linux_5_0: restore __kernel_fpu_{begin,restore}
In 5.0er these function were removed from the public interface also zfs needs
them for AVX/AES-NI support. Without this patch for example throughput on a
encrypted zfs dataset drops to 200 MB/s from 1.2 GB/s. These functions were
removed as their was no user within the linux kernel tree itself.
2019-05-06 14:14:40 +01:00

61 lines
1.8 KiB
Diff

From 245e0f743d814c9ff2d1c748175e321301eb16cf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=B6rg=20Thalheim?= <joerg@thalheim.io>
Date: Thu, 2 May 2019 05:28:08 +0100
Subject: [PATCH] x86/fpu: Export __kernel_fpu_{begin,end}()
This partially undo commit:
12209993 x86/fpu: Don't export __kernel_fpu_{begin,end}()
We need this symbol in zfs for AES-NI/AVX support.
---
arch/x86/include/asm/fpu/api.h | 2 ++
arch/x86/kernel/fpu/core.c | 6 ++++--
2 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/fpu/api.h b/arch/x86/include/asm/fpu/api.h
index b56d504af6545..7d53388d266ea 100644
--- a/arch/x86/include/asm/fpu/api.h
+++ b/arch/x86/include/asm/fpu/api.h
@@ -18,6 +18,8 @@
* If you intend to use the FPU in softirq you need to check first with
* irq_fpu_usable() if it is possible.
*/
+extern void __kernel_fpu_begin(void);
+extern void __kernel_fpu_end(void);
extern void kernel_fpu_begin(void);
extern void kernel_fpu_end(void);
extern bool irq_fpu_usable(void);
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 2e5003fef51a9..2ea85b32421a0 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -93,7 +93,7 @@ bool irq_fpu_usable(void)
}
EXPORT_SYMBOL(irq_fpu_usable);
-static void __kernel_fpu_begin(void)
+void __kernel_fpu_begin(void)
{
struct fpu *fpu = &current->thread.fpu;
@@ -111,8 +111,9 @@ static void __kernel_fpu_begin(void)
__cpu_invalidate_fpregs_state();
}
}
+EXPORT_SYMBOL(__kernel_fpu_begin);
-static void __kernel_fpu_end(void)
+void __kernel_fpu_end(void)
{
struct fpu *fpu = &current->thread.fpu;
@@ -121,6 +122,7 @@ static void __kernel_fpu_end(void)
kernel_fpu_enable();
}
+EXPORT_SYMBOL(__kernel_fpu_end);
void kernel_fpu_begin(void)
{