[Patch v6 04/16] x86/speculation: Rename SSBD update functions

From: Tim Chen
Date: Tue Nov 20 2018 - 19:34:38 EST


During context switch, the SSBD bit in SPEC_CTRL MSR is updated according
to changes in TIF_SSBD flag in the current and next running task.
Currently, only the bit controlling speculative store in SPEC_CTRL MSR
is updated and the related update functions all have "speculative_store"
or "ssb" in their names.

In later patches, other bits controlling STIBP in SPEC_CTRL MSR need
to be updated. The SPEC_CTRL MSR update functions should get rid of the
speculative store names as they will no longer be limited to SSBD update.

Rename the "speculative_store*" functions to a more generic name.

Signed-off-by: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/spec-ctrl.h | 6 +++---
arch/x86/kernel/cpu/bugs.c | 4 ++--
arch/x86/kernel/process.c | 12 ++++++------
3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/arch/x86/include/asm/spec-ctrl.h b/arch/x86/include/asm/spec-ctrl.h
index ae7c2c5..8e2f841 100644
--- a/arch/x86/include/asm/spec-ctrl.h
+++ b/arch/x86/include/asm/spec-ctrl.h
@@ -70,11 +70,11 @@ extern void speculative_store_bypass_ht_init(void);
static inline void speculative_store_bypass_ht_init(void) { }
#endif

-extern void speculative_store_bypass_update(unsigned long tif);
+extern void speculation_ctrl_update(unsigned long tif);

-static inline void speculative_store_bypass_update_current(void)
+static inline void speculation_ctrl_update_current(void)
{
- speculative_store_bypass_update(current_thread_info()->flags);
+ speculation_ctrl_update(current_thread_info()->flags);
}

#endif
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 199f27e..a63456a 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -202,7 +202,7 @@ x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool setguest)
tif = setguest ? ssbd_spec_ctrl_to_tif(guestval) :
ssbd_spec_ctrl_to_tif(hostval);

- speculative_store_bypass_update(tif);
+ speculation_ctrl_update(tif);
}
}
EXPORT_SYMBOL_GPL(x86_virt_spec_ctrl);
@@ -643,7 +643,7 @@ static int ssb_prctl_set(struct task_struct *task, unsigned long ctrl)
* mitigation until it is next scheduled.
*/
if (task == current && update)
- speculative_store_bypass_update_current();
+ speculation_ctrl_update_current();

return 0;
}
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index c93fcfd..8aa4960 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -395,27 +395,27 @@ static __always_inline void amd_set_ssb_virt_state(unsigned long tifn)
wrmsrl(MSR_AMD64_VIRT_SPEC_CTRL, ssbd_tif_to_spec_ctrl(tifn));
}

-static __always_inline void intel_set_ssb_state(unsigned long tifn)
+static __always_inline void spec_ctrl_update_msr(unsigned long tifn)
{
u64 msr = x86_spec_ctrl_base | ssbd_tif_to_spec_ctrl(tifn);

wrmsrl(MSR_IA32_SPEC_CTRL, msr);
}

-static __always_inline void __speculative_store_bypass_update(unsigned long tifn)
+static __always_inline void __speculation_ctrl_update(unsigned long tifn)
{
if (static_cpu_has(X86_FEATURE_VIRT_SSBD))
amd_set_ssb_virt_state(tifn);
else if (static_cpu_has(X86_FEATURE_LS_CFG_SSBD))
amd_set_core_ssb_state(tifn);
else
- intel_set_ssb_state(tifn);
+ spec_ctrl_update_msr(tifn);
}

-void speculative_store_bypass_update(unsigned long tif)
+void speculation_ctrl_update(unsigned long tif)
{
preempt_disable();
- __speculative_store_bypass_update(tif);
+ __speculation_ctrl_update(tif);
preempt_enable();
}

@@ -452,7 +452,7 @@ void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
set_cpuid_faulting(!!(tifn & _TIF_NOCPUID));

if ((tifp ^ tifn) & _TIF_SSBD)
- __speculative_store_bypass_update(tifn);
+ __speculation_ctrl_update(tifn);
}

/*
--
2.9.4