On 5/12/20 5:01 PM, Thomas Gleixner wrote: > Convert the XEN/PV hypercall to IDTENTRY: > > - Emit the ASM stub with DECLARE_IDTENTRY > - Remove the ASM idtentry in 64bit > - Remove the open coded ASM entry code in 32bit > - Remove the old prototypes > > The handler stubs need to stay in ASM code as it needs corner case handling > and adjustment of the stack pointer. > > Provide a new C function which invokes the entry/exit handling and calls > into the XEN handler on the interrupt stack. > > The exit code is slightly different from the regular idtentry_exit() on > non-preemptible kernels. If the hypercall is preemptible and need_resched() > is set then XEN provides a preempt hypercall scheduling function. Add it as > conditional path to __idtentry_exit() so the function can be reused. > > __idtentry_exit() is forced inlined so on the regular idtentry_exit() path > the extra condition is optimized out by the compiler. > > Signed-off-by: Thomas Gleixner <[email protected]> > Cc: Boris Ostrovsky <[email protected]> > Cc: Juergen Gross <[email protected]> > --- > V5: Move DECLARE_PER_CPU(bool, xen_in_preemptible_hcall) out of ifdeffery > to avoid #ifdeffery in idtentry_exit(). > Convert to the reworked stack switching helper > Fixed up the XEN callback initialization (Boris O.) > --- > arch/x86/entry/common.c | 57 > ++++++++++++++++++++++++++++++++++++++-- > arch/x86/entry/entry_32.S | 17 ++++++----- > arch/x86/entry/entry_64.S | 22 ++++----------- > arch/x86/include/asm/idtentry.h | 13 +++++++++ > arch/x86/xen/setup.c | 4 ++ > arch/x86/xen/smp_pv.c | 3 +- > arch/x86/xen/xen-asm_32.S | 12 ++++---- > arch/x86/xen/xen-asm_64.S | 2 - > arch/x86/xen/xen-ops.h | 1 > drivers/xen/preempt.c | 2 - > include/xen/xen-ops.h | 7 +++- > 11 files changed, 103 insertions(+), 37 deletions(-)
Reviewed-by: Boris Ostrovsky <[email protected]>
