[PATCH] [10/40] i386: Use patch site IDs computed from offset in paravirt_ops structure
From: Jeremy Fitzhardinge <[EMAIL PROTECTED]>
Use patch type identifiers derived from the offset of the operation in
the paravirt_ops structure. This avoids having to maintain a separate
enum for patch site types.
Also, since the identifier is derived from the offset into
paravirt_ops, the offset can be derived from the identifier. This is
used to remove replicated information in the various callsite macros,
which has been a source of bugs in the past.
This patch also drops the fused save_fl+cli operation, which doesn't
really add much and makes things more complex - specifically because
it breaks the 1:1 relationship between identifiers and offsets. If
this operation turns out to be particularly beneficial, then the right
answer is to define a new entrypoint for it.
Signed-off-by: Jeremy Fitzhardinge <[EMAIL PROTECTED]>
Signed-off-by: Andi Kleen <[EMAIL PROTECTED]>
Cc: Rusty Russell <[EMAIL PROTECTED]>
Cc: Zachary Amsden <[EMAIL PROTECTED]>
---
arch/i386/kernel/paravirt.c | 14 +--
arch/i386/kernel/vmi.c | 39 +
include/asm-i386/paravirt.h | 179 ++--
3 files changed, 105 insertions(+), 127 deletions(-)
===
Index: linux/arch/i386/kernel/paravirt.c
===
--- linux.orig/arch/i386/kernel/paravirt.c
+++ linux/arch/i386/kernel/paravirt.c
@@ -58,7 +58,6 @@ DEF_NATIVE(cli, "cli");
DEF_NATIVE(sti, "sti");
DEF_NATIVE(popf, "push %eax; popf");
DEF_NATIVE(pushf, "pushf; pop %eax");
-DEF_NATIVE(pushf_cli, "pushf; pop %eax; cli");
DEF_NATIVE(iret, "iret");
DEF_NATIVE(sti_sysexit, "sti; sysexit");
@@ -66,13 +65,12 @@ static const struct native_insns
{
const char *start, *end;
} native_insns[] = {
- [PARAVIRT_IRQ_DISABLE] = { start_cli, end_cli },
- [PARAVIRT_IRQ_ENABLE] = { start_sti, end_sti },
- [PARAVIRT_RESTORE_FLAGS] = { start_popf, end_popf },
- [PARAVIRT_SAVE_FLAGS] = { start_pushf, end_pushf },
- [PARAVIRT_SAVE_FLAGS_IRQ_DISABLE] = { start_pushf_cli, end_pushf_cli },
- [PARAVIRT_INTERRUPT_RETURN] = { start_iret, end_iret },
- [PARAVIRT_STI_SYSEXIT] = { start_sti_sysexit, end_sti_sysexit },
+ [PARAVIRT_PATCH(irq_disable)] = { start_cli, end_cli },
+ [PARAVIRT_PATCH(irq_enable)] = { start_sti, end_sti },
+ [PARAVIRT_PATCH(restore_fl)] = { start_popf, end_popf },
+ [PARAVIRT_PATCH(save_fl)] = { start_pushf, end_pushf },
+ [PARAVIRT_PATCH(iret)] = { start_iret, end_iret },
+ [PARAVIRT_PATCH(irq_enable_sysexit)] = { start_sti_sysexit,
end_sti_sysexit },
};
static unsigned native_patch(u8 type, u16 clobbers, void *insns, unsigned len)
Index: linux/arch/i386/kernel/vmi.c
===
--- linux.orig/arch/i386/kernel/vmi.c
+++ linux/arch/i386/kernel/vmi.c
@@ -83,11 +83,6 @@ extern struct paravirt_patch __start_par
#define MNEM_JMP 0xe9
#define MNEM_RET 0xc3
-static char irq_save_disable_callout[] = {
- MNEM_CALL, 0, 0, 0, 0,
- MNEM_CALL, 0, 0, 0, 0,
- MNEM_RET
-};
#define IRQ_PATCH_INT_MASK 0
#define IRQ_PATCH_DISABLE 5
@@ -135,33 +130,17 @@ static unsigned patch_internal(int call,
static unsigned vmi_patch(u8 type, u16 clobbers, void *insns, unsigned len)
{
switch (type) {
- case PARAVIRT_IRQ_DISABLE:
+ case PARAVIRT_PATCH(irq_disable):
return patch_internal(VMI_CALL_DisableInterrupts, len,
insns);
- case PARAVIRT_IRQ_ENABLE:
+ case PARAVIRT_PATCH(irq_enable):
return patch_internal(VMI_CALL_EnableInterrupts, len,
insns);
- case PARAVIRT_RESTORE_FLAGS:
+ case PARAVIRT_PATCH(restore_fl):
return patch_internal(VMI_CALL_SetInterruptMask, len,
insns);
- case PARAVIRT_SAVE_FLAGS:
+ case PARAVIRT_PATCH(save_fl):
return patch_internal(VMI_CALL_GetInterruptMask, len,
insns);
- case PARAVIRT_SAVE_FLAGS_IRQ_DISABLE:
- if (len >= 10) {
- patch_internal(VMI_CALL_GetInterruptMask, len,
insns);
- patch_internal(VMI_CALL_DisableInterrupts,
len-5, insns+5);
- return 10;
- } else {
- /*
-* You bastards didn't leave enough room to
-* patch save_flags_irq_disable inline. Patch
-* to a helper
-*/
- BUG_ON(len < 5);
- *(char *)insns = MNEM_CALL;
- patch_offset(insns, irq_save_disable_callout);
- return 5;
- }
[PATCH] [10/40] i386: Use patch site IDs computed from offset in paravirt_ops structure
From: Jeremy Fitzhardinge [EMAIL PROTECTED]
Use patch type identifiers derived from the offset of the operation in
the paravirt_ops structure. This avoids having to maintain a separate
enum for patch site types.
Also, since the identifier is derived from the offset into
paravirt_ops, the offset can be derived from the identifier. This is
used to remove replicated information in the various callsite macros,
which has been a source of bugs in the past.
This patch also drops the fused save_fl+cli operation, which doesn't
really add much and makes things more complex - specifically because
it breaks the 1:1 relationship between identifiers and offsets. If
this operation turns out to be particularly beneficial, then the right
answer is to define a new entrypoint for it.
Signed-off-by: Jeremy Fitzhardinge [EMAIL PROTECTED]
Signed-off-by: Andi Kleen [EMAIL PROTECTED]
Cc: Rusty Russell [EMAIL PROTECTED]
Cc: Zachary Amsden [EMAIL PROTECTED]
---
arch/i386/kernel/paravirt.c | 14 +--
arch/i386/kernel/vmi.c | 39 +
include/asm-i386/paravirt.h | 179 ++--
3 files changed, 105 insertions(+), 127 deletions(-)
===
Index: linux/arch/i386/kernel/paravirt.c
===
--- linux.orig/arch/i386/kernel/paravirt.c
+++ linux/arch/i386/kernel/paravirt.c
@@ -58,7 +58,6 @@ DEF_NATIVE(cli, cli);
DEF_NATIVE(sti, sti);
DEF_NATIVE(popf, push %eax; popf);
DEF_NATIVE(pushf, pushf; pop %eax);
-DEF_NATIVE(pushf_cli, pushf; pop %eax; cli);
DEF_NATIVE(iret, iret);
DEF_NATIVE(sti_sysexit, sti; sysexit);
@@ -66,13 +65,12 @@ static const struct native_insns
{
const char *start, *end;
} native_insns[] = {
- [PARAVIRT_IRQ_DISABLE] = { start_cli, end_cli },
- [PARAVIRT_IRQ_ENABLE] = { start_sti, end_sti },
- [PARAVIRT_RESTORE_FLAGS] = { start_popf, end_popf },
- [PARAVIRT_SAVE_FLAGS] = { start_pushf, end_pushf },
- [PARAVIRT_SAVE_FLAGS_IRQ_DISABLE] = { start_pushf_cli, end_pushf_cli },
- [PARAVIRT_INTERRUPT_RETURN] = { start_iret, end_iret },
- [PARAVIRT_STI_SYSEXIT] = { start_sti_sysexit, end_sti_sysexit },
+ [PARAVIRT_PATCH(irq_disable)] = { start_cli, end_cli },
+ [PARAVIRT_PATCH(irq_enable)] = { start_sti, end_sti },
+ [PARAVIRT_PATCH(restore_fl)] = { start_popf, end_popf },
+ [PARAVIRT_PATCH(save_fl)] = { start_pushf, end_pushf },
+ [PARAVIRT_PATCH(iret)] = { start_iret, end_iret },
+ [PARAVIRT_PATCH(irq_enable_sysexit)] = { start_sti_sysexit,
end_sti_sysexit },
};
static unsigned native_patch(u8 type, u16 clobbers, void *insns, unsigned len)
Index: linux/arch/i386/kernel/vmi.c
===
--- linux.orig/arch/i386/kernel/vmi.c
+++ linux/arch/i386/kernel/vmi.c
@@ -83,11 +83,6 @@ extern struct paravirt_patch __start_par
#define MNEM_JMP 0xe9
#define MNEM_RET 0xc3
-static char irq_save_disable_callout[] = {
- MNEM_CALL, 0, 0, 0, 0,
- MNEM_CALL, 0, 0, 0, 0,
- MNEM_RET
-};
#define IRQ_PATCH_INT_MASK 0
#define IRQ_PATCH_DISABLE 5
@@ -135,33 +130,17 @@ static unsigned patch_internal(int call,
static unsigned vmi_patch(u8 type, u16 clobbers, void *insns, unsigned len)
{
switch (type) {
- case PARAVIRT_IRQ_DISABLE:
+ case PARAVIRT_PATCH(irq_disable):
return patch_internal(VMI_CALL_DisableInterrupts, len,
insns);
- case PARAVIRT_IRQ_ENABLE:
+ case PARAVIRT_PATCH(irq_enable):
return patch_internal(VMI_CALL_EnableInterrupts, len,
insns);
- case PARAVIRT_RESTORE_FLAGS:
+ case PARAVIRT_PATCH(restore_fl):
return patch_internal(VMI_CALL_SetInterruptMask, len,
insns);
- case PARAVIRT_SAVE_FLAGS:
+ case PARAVIRT_PATCH(save_fl):
return patch_internal(VMI_CALL_GetInterruptMask, len,
insns);
- case PARAVIRT_SAVE_FLAGS_IRQ_DISABLE:
- if (len = 10) {
- patch_internal(VMI_CALL_GetInterruptMask, len,
insns);
- patch_internal(VMI_CALL_DisableInterrupts,
len-5, insns+5);
- return 10;
- } else {
- /*
-* You bastards didn't leave enough room to
-* patch save_flags_irq_disable inline. Patch
-* to a helper
-*/
- BUG_ON(len 5);
- *(char *)insns = MNEM_CALL;
- patch_offset(insns, irq_save_disable_callout);
- return 5;
- }
- case
