powerpc/watchpoint: Provide DAWR number to __set_breakpoint

Introduce new parameter 'nr' to __set_breakpoint() which indicates
which DAWR should be programed. Also convert current_brk variable
to an array.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Michael Neuling <mikey@neuling.org>
Link: https://lore.kernel.org/r/20200514111741.97993-7-ravi.bangoria@linux.ibm.com

diff --git a/arch/powerpc/include/asm/debug.h b/arch/powerpc/include/asm/debug.h
index 7756026..ec57daf 100644 (file)
--- a/arch/powerpc/include/asm/debug.h
+++ b/arch/powerpc/include/asm/debug.h
@@ -45,7 +45,7 @@ static inline int debugger_break_match(struct pt_regs *regs) { return 0; }
 static inline int debugger_fault_handler(struct pt_regs *regs) { return 0; }
 #endif
 
-void __set_breakpoint(struct arch_hw_breakpoint *brk);
+void __set_breakpoint(int nr, struct arch_hw_breakpoint *brk);
 bool ppc_breakpoint_available(void);
 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 extern void do_send_trap(struct pt_regs *regs, unsigned long address,

diff --git a/arch/powerpc/include/asm/hw_breakpoint.h b/arch/powerpc/include/asm/hw_breakpoint.h
index 5b3b028..1120c7d 100644 (file)
--- a/arch/powerpc/include/asm/hw_breakpoint.h
+++ b/arch/powerpc/include/asm/hw_breakpoint.h
@@ -85,7 +85,7 @@ static inline void hw_breakpoint_disable(void)
        brk.len = 0;
        brk.hw_len = 0;
        if (ppc_breakpoint_available())
-               __set_breakpoint(&brk);
+               __set_breakpoint(0, &brk);
 }
 extern void thread_change_pc(struct task_struct *tsk, struct pt_regs *regs);
 int hw_breakpoint_handler(struct die_args *args);

diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c
index 01f07d9..f547240 100644 (file)
--- a/arch/powerpc/kernel/hw_breakpoint.c
+++ b/arch/powerpc/kernel/hw_breakpoint.c
@@ -64,7 +64,7 @@ int arch_install_hw_breakpoint(struct perf_event *bp)
         * If so, DABR will be populated in single_step_dabr_instruction().
         */
        if (current->thread.last_hit_ubp != bp)
-               __set_breakpoint(info);
+               __set_breakpoint(0, info);
 
        return 0;
 }
@@ -222,7 +222,7 @@ void thread_change_pc(struct task_struct *tsk, struct pt_regs *regs)
 
        info = counter_arch_bp(tsk->thread.last_hit_ubp);
        regs->msr &= ~MSR_SE;
-       __set_breakpoint(info);
+       __set_breakpoint(0, info);
        tsk->thread.last_hit_ubp = NULL;
 }
 
@@ -347,7 +347,7 @@ int hw_breakpoint_handler(struct die_args *args)
        if (!(info->type & HW_BRK_TYPE_EXTRANEOUS_IRQ))
                perf_bp_event(bp, regs);
 
-       __set_breakpoint(info);
+       __set_breakpoint(0, info);
 out:
        rcu_read_unlock();
        return rc;
@@ -380,7 +380,7 @@ static int single_step_dabr_instruction(struct die_args *args)
        if (!(info->type & HW_BRK_TYPE_EXTRANEOUS_IRQ))
                perf_bp_event(bp, regs);
 
-       __set_breakpoint(info);
+       __set_breakpoint(0, info);
        current->thread.last_hit_ubp = NULL;
 
        /*

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index dc161b0..f303aea 100644 (file)
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -637,7 +637,7 @@ void do_break (struct pt_regs *regs, unsigned long address,
 }
 #endif /* CONFIG_PPC_ADV_DEBUG_REGS */
 
-static DEFINE_PER_CPU(struct arch_hw_breakpoint, current_brk);
+static DEFINE_PER_CPU(struct arch_hw_breakpoint, current_brk[HBP_NUM_MAX]);
 
 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 /*
@@ -714,7 +714,7 @@ EXPORT_SYMBOL_GPL(switch_booke_debug_regs);
 static void set_breakpoint(struct arch_hw_breakpoint *brk)
 {
        preempt_disable();
-       __set_breakpoint(brk);
+       __set_breakpoint(0, brk);
        preempt_enable();
 }
 
@@ -800,13 +800,13 @@ static inline int set_breakpoint_8xx(struct arch_hw_breakpoint *brk)
        return 0;
 }
 
-void __set_breakpoint(struct arch_hw_breakpoint *brk)
+void __set_breakpoint(int nr, struct arch_hw_breakpoint *brk)
 {
-       memcpy(this_cpu_ptr(&current_brk), brk, sizeof(*brk));
+       memcpy(this_cpu_ptr(&current_brk[nr]), brk, sizeof(*brk));
 
        if (dawr_enabled())
                // Power8 or later
-               set_dawr(0, brk);
+               set_dawr(nr, brk);
        else if (IS_ENABLED(CONFIG_PPC_8xx))
                set_breakpoint_8xx(brk);
        else if (!cpu_has_feature(CPU_FTR_ARCH_207S))
@@ -1174,8 +1174,8 @@ struct task_struct *__switch_to(struct task_struct *prev,
  * schedule DABR
  */
 #ifndef CONFIG_HAVE_HW_BREAKPOINT
-       if (unlikely(!hw_brk_match(this_cpu_ptr(&current_brk), &new->thread.hw_brk)))
-               __set_breakpoint(&new->thread.hw_brk);
+       if (unlikely(!hw_brk_match(this_cpu_ptr(&current_brk[0]), &new->thread.hw_brk)))
+               __set_breakpoint(0, &new->thread.hw_brk);
 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
 #endif
 

diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index a46c3fd..8e29138 100644 (file)
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -272,7 +272,7 @@ static void do_signal(struct task_struct *tsk)
         * triggered inside the kernel.
         */
        if (tsk->thread.hw_brk.address && tsk->thread.hw_brk.type)
-               __set_breakpoint(&tsk->thread.hw_brk);
+               __set_breakpoint(0, &tsk->thread.hw_brk);
 #endif
        /* Re-enable the breakpoints for the signal stack */
        thread_change_pc(tsk, tsk->thread.regs);

diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index effb10c..30b3e3d 100644 (file)
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -954,7 +954,7 @@ static void insert_cpu_bpts(void)
                brk.address = dabr.address;
                brk.type = (dabr.enabled & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL;
                brk.len = DABR_MAX_LEN;
-               __set_breakpoint(&brk);
+               __set_breakpoint(0, &brk);
        }
 
        if (iabr)