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		668f62ec62
		
	
	
	
	
		
			
			When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  Convert
    if (!foo(..., &err)) {
        ...
        error_propagate(errp, err);
        ...
        return ...
    }
to
    if (!foo(..., errp)) {
        ...
        ...
        return ...
    }
where nothing else needs @err.  Coccinelle script:
    @rule1 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
         if (
    (
    -        fun(args, &err, args2)
    +        fun(args, errp, args2)
    |
    -        !fun(args, &err, args2)
    +        !fun(args, errp, args2)
    |
    -        fun(args, &err, args2) op c1
    +        fun(args, errp, args2) op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    )
         }
    @rule2 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    expression var;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
    -    var = fun(args, &err, args2);
    +    var = fun(args, errp, args2);
         ... when != err
         if (
    (
             var
    |
             !var
    |
             var op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    |
             return var;
    )
         }
    @depends on rule1 || rule2@
    identifier err;
    @@
    -    Error *err = NULL;
         ... when != err
Not exactly elegant, I'm afraid.
The "when != lbl:" is necessary to avoid transforming
         if (fun(args, &err)) {
             goto out
         }
         ...
     out:
         error_propagate(errp, err);
even though other paths to label out still need the error_propagate().
For an actual example, see sclp_realize().
Without the "when strict", Coccinelle transforms vfio_msix_setup(),
incorrectly.  I don't know what exactly "when strict" does, only that
it helps here.
The match of return is narrower than what I want, but I can't figure
out how to express "return where the operand doesn't use @err".  For
an example where it's too narrow, see vfio_intx_enable().
Silently fails to convert hw/arm/armsse.c, because Coccinelle gets
confused by ARMSSE being used both as typedef and function-like macro
there.  Converted manually.
Line breaks tidied up manually.  One nested declaration of @local_err
deleted manually.  Preexisting unwanted blank line dropped in
hw/riscv/sifive_e.c.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-35-armbru@redhat.com>
		
	
			
		
			
				
	
	
		
			101 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			101 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * CPU core abstract device
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|  *
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|  * Copyright (C) 2016 Bharata B Rao <bharata@linux.vnet.ibm.com>
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|  *
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|  * This work is licensed under the terms of the GNU GPL, version 2 or later.
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|  * See the COPYING file in the top-level directory.
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|  */
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| 
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| #include "qemu/osdep.h"
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| #include "hw/cpu/core.h"
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| #include "qapi/visitor.h"
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| #include "qemu/module.h"
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| #include "qapi/error.h"
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| #include "sysemu/cpus.h"
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| #include "hw/boards.h"
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| 
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| static void core_prop_get_core_id(Object *obj, Visitor *v, const char *name,
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|                                   void *opaque, Error **errp)
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| {
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|     CPUCore *core = CPU_CORE(obj);
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|     int64_t value = core->core_id;
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| 
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|     visit_type_int(v, name, &value, errp);
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| }
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| 
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| static void core_prop_set_core_id(Object *obj, Visitor *v, const char *name,
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|                                   void *opaque, Error **errp)
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| {
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|     CPUCore *core = CPU_CORE(obj);
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|     int64_t value;
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| 
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|     if (!visit_type_int(v, name, &value, errp)) {
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|         return;
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|     }
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| 
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|     if (value < 0) {
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|         error_setg(errp, "Invalid core id %"PRId64, value);
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|         return;
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|     }
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| 
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|     core->core_id = value;
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| }
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| 
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| static void core_prop_get_nr_threads(Object *obj, Visitor *v, const char *name,
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|                                      void *opaque, Error **errp)
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| {
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|     CPUCore *core = CPU_CORE(obj);
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|     int64_t value = core->nr_threads;
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| 
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|     visit_type_int(v, name, &value, errp);
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| }
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| 
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| static void core_prop_set_nr_threads(Object *obj, Visitor *v, const char *name,
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|                                      void *opaque, Error **errp)
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| {
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|     CPUCore *core = CPU_CORE(obj);
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|     int64_t value;
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| 
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|     if (!visit_type_int(v, name, &value, errp)) {
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|         return;
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|     }
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| 
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|     core->nr_threads = value;
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| }
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| 
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| static void cpu_core_instance_init(Object *obj)
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| {
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|     MachineState *ms = MACHINE(qdev_get_machine());
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|     CPUCore *core = CPU_CORE(obj);
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| 
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|     object_property_add(obj, "core-id", "int", core_prop_get_core_id,
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|                         core_prop_set_core_id, NULL, NULL);
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|     object_property_add(obj, "nr-threads", "int", core_prop_get_nr_threads,
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|                         core_prop_set_nr_threads, NULL, NULL);
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|     core->nr_threads = ms->smp.threads;
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| }
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| 
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| static void cpu_core_class_init(ObjectClass *oc, void *data)
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| {
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|     DeviceClass *dc = DEVICE_CLASS(oc);
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| 
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|     set_bit(DEVICE_CATEGORY_CPU, dc->categories);
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| }
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| 
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| static const TypeInfo cpu_core_type_info = {
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|     .name = TYPE_CPU_CORE,
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|     .parent = TYPE_DEVICE,
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|     .abstract = true,
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|     .class_init = cpu_core_class_init,
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|     .instance_size = sizeof(CPUCore),
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|     .instance_init = cpu_core_instance_init,
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| };
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| 
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| static void cpu_core_register_types(void)
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| {
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|     type_register_static(&cpu_core_type_info);
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| }
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| 
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| type_init(cpu_core_register_types)
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