> -----Original Message----- > From: Thomas Gleixner [mailto:[email protected]] > Sent: Sunday, August 27, 2017 11:48 PM > To: LKML <[email protected]> > Cc: Ingo Molnar <[email protected]>; Peter Anvin <[email protected]>; Peter > Zijlstra <[email protected]>; Andy Lutomirski <[email protected]>; > Borislav Petkov <[email protected]>; Steven Rostedt <[email protected]>; > Juergen Gross <[email protected]>; KY Srinivasan <[email protected]>; > Stephen Hemminger <[email protected]>; Boris Ostrovsky > <[email protected]> > Subject: [patch V3 43/44] x86/idt: Simplify alloc_intr_gate > > The only users of alloc_intr_gate() are hypervisors, which both check the > used_vectors bitmap whether they have allocated the gate already. Move > that > check into alloc_intr_gate() and simplify the users. > > Signed-off-by: Thomas Gleixner <[email protected]> > Reviewed-by: Juergen Gross <[email protected]> > Cc: "K. Y. Srinivasan" <[email protected]>
Reviewed-by: K. Y. Srinivasan <[email protected]> > Cc: Stephen Hemminger <[email protected]> > Cc: Boris Ostrovsky <[email protected]> > Cc: Juergen Gross <[email protected]> > --- > arch/x86/kernel/cpu/mshyperv.c | 9 ++------- > arch/x86/kernel/idt.c | 6 +++--- > drivers/xen/events/events_base.c | 6 ++---- > 3 files changed, 7 insertions(+), 14 deletions(-) > > --- a/arch/x86/kernel/cpu/mshyperv.c > +++ b/arch/x86/kernel/cpu/mshyperv.c > @@ -59,13 +59,8 @@ void hyperv_vector_handler(struct pt_reg > void hv_setup_vmbus_irq(void (*handler)(void)) > { > vmbus_handler = handler; > - /* > - * Setup the IDT for hypervisor callback. Prevent reallocation > - * at module reload. > - */ > - if (!test_bit(HYPERVISOR_CALLBACK_VECTOR, used_vectors)) > - alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, > - hyperv_callback_vector); > + /* Setup the IDT for hypervisor callback */ > + alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, > hyperv_callback_vector); > } > > void hv_remove_vmbus_irq(void) > --- a/arch/x86/kernel/idt.c > +++ b/arch/x86/kernel/idt.c > @@ -354,7 +354,7 @@ void set_intr_gate(unsigned int n, const > > void alloc_intr_gate(unsigned int n, const void *addr) > { > - BUG_ON(test_bit(n, used_vectors) || n < FIRST_SYSTEM_VECTOR); > - set_bit(n, used_vectors); > - set_intr_gate(n, addr); > + BUG_ON(n < FIRST_SYSTEM_VECTOR); > + if (!test_and_set_bit(n, used_vectors)) > + set_intr_gate(n, addr); > } > --- a/drivers/xen/events/events_base.c > +++ b/drivers/xen/events/events_base.c > @@ -1653,10 +1653,8 @@ void xen_callback_vector(void) > return; > } > pr_info("Xen HVM callback vector for event delivery is > enabled\n"); > - /* in the restore case the vector has already been allocated > */ > - if (!test_bit(HYPERVISOR_CALLBACK_VECTOR, > used_vectors)) > - alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, > - xen_hvm_callback_vector); > + alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, > + xen_hvm_callback_vector); > } > } > #else >
