x86: Use the new schedule_user API on userspace preemption

This way we can exit the RCU extended quiescent state before
we schedule a new task from irq/exception exit.

Signed-off-by: Frederic Weisbecker <[email protected]>
Cc: Alessio Igor Bogani <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Avi Kivity <[email protected]>
Cc: Chris Metcalf <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Geoff Levand <[email protected]>
Cc: Gilad Ben Yossef <[email protected]>
Cc: Hakan Akkan <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Josh Triplett <[email protected]>
Cc: Kevin Hilman <[email protected]>
Cc: Max Krasnyansky <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephen Hemminger <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Sven-Thorsten Dietrich <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Josh Triplett <[email protected]>

diff --git a/arch/x86/include/asm/rcu.h b/arch/x86/include/asm/rcu.h
index 439815b35ced75021a7fe5126895f73bdc47a214..d1ac07a23979fdc96ce0dac11ed7b6efe2821de8 100644 (file)
--- a/arch/x86/include/asm/rcu.h
+++ b/arch/x86/include/asm/rcu.h
@@ -1,6 +1,8 @@
 #ifndef _ASM_X86_RCU_H
 #define _ASM_X86_RCU_H
 
+#ifndef __ASSEMBLY__
+
 #include <linux/rcupdate.h>
 #include <asm/ptrace.h>
 
@@ -17,4 +19,14 @@ static inline void exception_exit(struct pt_regs *regs)
 #endif
 }
 
+#else /* __ASSEMBLY__ */
+
+#ifdef CONFIG_RCU_USER_QS
+# define SCHEDULE_USER call schedule_user
+#else
+# define SCHEDULE_USER call schedule
+#endif
+
+#endif /* !__ASSEMBLY__ */
+
 #endif

diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 69babd8c834f920b4d54c48e1f41a08d4f7fef6f..1a8f3cbb6ee30accdaa986189152009c634d8da6 100644 (file)
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -56,6 +56,7 @@
 #include <asm/ftrace.h>
 #include <asm/percpu.h>
 #include <asm/asm.h>
+#include <asm/rcu.h>
 #include <linux/err.h>
 
 /* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this.  */
@@ -565,7 +566,7 @@ sysret_careful:
        TRACE_IRQS_ON
        ENABLE_INTERRUPTS(CLBR_NONE)
        pushq_cfi %rdi
-       call schedule
+       SCHEDULE_USER
        popq_cfi %rdi
        jmp sysret_check
 
@@ -678,7 +679,7 @@ int_careful:
        TRACE_IRQS_ON
        ENABLE_INTERRUPTS(CLBR_NONE)
        pushq_cfi %rdi
-       call schedule
+       SCHEDULE_USER
        popq_cfi %rdi
        DISABLE_INTERRUPTS(CLBR_NONE)
        TRACE_IRQS_OFF
@@ -974,7 +975,7 @@ retint_careful:
        TRACE_IRQS_ON
        ENABLE_INTERRUPTS(CLBR_NONE)
        pushq_cfi %rdi
-       call  schedule
+       SCHEDULE_USER
        popq_cfi %rdi
        GET_THREAD_INFO(%rcx)
        DISABLE_INTERRUPTS(CLBR_NONE)
@@ -1449,7 +1450,7 @@ paranoid_userspace:
 paranoid_schedule:
        TRACE_IRQS_ON
        ENABLE_INTERRUPTS(CLBR_ANY)
-       call schedule
+       SCHEDULE_USER
        DISABLE_INTERRUPTS(CLBR_ANY)
        TRACE_IRQS_OFF
        jmp paranoid_userspace