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]>
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
> -----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
>
Commit-ID: 4447ac1195a845b18f2f427686f116ab77c5b268
Gitweb: http://git.kernel.org/tip/4447ac1195a845b18f2f427686f116ab77c5b268
Author: Thomas Gleixner <[email protected]>
AuthorDate: Mon, 28 Aug 2017 08:47:58 +0200
Committer: Ingo Molnar <[email protected]>
CommitDate: Tue, 29 Aug 2017 12:07:28 +0200
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]>
Reviewed-by: K. Y. Srinivasan <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Boris Ostrovsky <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephen Hemminger <[email protected]>
Cc: Steven Rostedt <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[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(-)
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 70e717f..9fc3265 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -59,13 +59,8 @@ void hyperv_vector_handler(struct pt_regs *regs)
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)
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 8e9318d..b609eac 100644
--- 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 *addr)
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);
}
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 2d43118..1ab4bd1 100644
--- 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