Use the fpu_lock to do the work of saving and restoring
Signed-off-by: Benoît Canet <[email protected]>
---
arch/x64/entry.S | 2 +-
linux.cc | 4 ++++
2 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/arch/x64/entry.S b/arch/x64/entry.S
index dda7358..cd23cec 100644
--- a/arch/x64/entry.S
+++ b/arch/x64/entry.S
@@ -217,7 +217,6 @@ syscall_entry:
# From
http://stackoverflow.com/questions/2535989/what-are-the-calling-conventions-for-unix-linux-system-calls-on-x86-64:
# "User-level applications use as integer registers for passing the
sequence %rdi, %rsi, %rdx, %rcx, %r8 and %r9. The kernel interface uses %rdi,
%rsi, %rdx, %r10, %r8 and %r9"
- # FIXME: fpu
pushq_cfi %rbx
pushq_cfi %rdx
pushq_cfi %rsi
@@ -250,6 +249,7 @@ syscall_entry:
# Because we pushed an even number of 8 bytes after aligning the stack,
# it is still 16-byte aligned and we don't need to adjust it here.
+ # FPU save/restore is done inside the wrapper
callq syscall_wrapper
popq_cfi %r9
diff --git a/linux.cc b/linux.cc
index 4ab88f3..63377c1 100644
--- a/linux.cc
+++ b/linux.cc
@@ -311,6 +311,10 @@ static int sys_exit(int ret)
long syscall(long number, ...)
{
+ // Save FPU state and restore it at the end of this function
+ sched::fpu_lock fpu;
+ SCOPE_LOCK(fpu);
+
switch (number) {
SYSCALL2(open, const char *, int);
SYSCALL3(read, int, char *, size_t);
--
2.7.4
--
You received this message because you are subscribed to the Google Groups "OSv
Development" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
For more options, visit https://groups.google.com/d/optout.
