Commit 468e3a1a authored by Fabiano Rosas's avatar Fabiano Rosas Committed by David Gibson
Browse files

target/ppc: Refactor kvm_handle_debug 



There are four scenarios being handled in this function:

- single stepping
- hardware breakpoints
- software breakpoints
- fallback (no debug supported)

A future patch will add code to handle specific single step and
software breakpoints cases so let's split each scenario into its own
function now to avoid hurting readability.

Signed-off-by: default avatarFabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: default avatarAlexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20190228225759.21328-5-farosas@linux.ibm.com>
Signed-off-by: default avatarDavid Gibson <david@gibson.dropbear.id.au>
parent 2cbd1581

target/ppc/kvm.c

+50 −36
Original line number Diff line number Diff line
@@ -1624,21 +1624,36 @@ static int kvm_handle_hw_breakpoint(CPUState *cs, 
    return handle;

}



static int kvm_handle_singlestep(void)

{

    return 1;

}



static int kvm_handle_sw_breakpoint(void)

{

    return 1;

}



static int kvm_handle_debug(PowerPCCPU *cpu, struct kvm_run *run)

{

    CPUState *cs = CPU(cpu);

    CPUPPCState *env = &cpu->env;

    struct kvm_debug_exit_arch *arch_info = &run->debug.arch;

    int handle = 0;



    if (cs->singlestep_enabled) {

        handle = 1;

    } else if (arch_info->status) {

        handle = kvm_handle_hw_breakpoint(cs, arch_info);

    } else if (kvm_find_sw_breakpoint(cs, arch_info->address)) {

        handle = 1;

    } else {

        /* QEMU is not able to handle debug exception, so inject

        return kvm_handle_singlestep();

    }



    if (arch_info->status) {

        return kvm_handle_hw_breakpoint(cs, arch_info);

    }



    if (kvm_find_sw_breakpoint(cs, arch_info->address)) {

        return kvm_handle_sw_breakpoint();

    }



    /*

     * QEMU is not able to handle debug exception, so inject

     * program exception to guest;

     * Yes program exception NOT debug exception !!

     * When QEMU is using debug resources then debug exception must
@@ -1658,18 +1673,17 @@ static int kvm_handle_debug(PowerPCCPU *cpu, struct kvm_run *run) 
     * privileged / illegal instruction and that's why we are

     * injecting a program interrupt.

     */



    cpu_synchronize_state(cs);

        /* env->nip is PC, so increment this by 4 to use

    /*

     * env->nip is PC, so increment this by 4 to use

     * ppc_cpu_do_interrupt(), which set srr0 = env->nip - 4.

     */

    env->nip += 4;

    cs->exception_index = POWERPC_EXCP_PROGRAM;

    env->error_code = POWERPC_EXCP_INVAL;

    ppc_cpu_do_interrupt(cs);

    }



    return handle;

    return 0;

}



int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run)