trace: include CPU index in trace_memory_region_*()

Knowing which CPU performed an action is essential for understanding SMP guest
behavior.

However, cpu_physical_memory_rw() may be executed by a machine init function,
before any VCPUs are running, when there is no CPU running ('current_cpu' is
NULL). In this case, store -1 in the trace record as the CPU index. Trace
analysis tools may need to be aware of this special case.

Signed-off-by: Hollis Blanchard <hollis_blanchard@mentor.com>
Message-id: 1456949575-1633-1-git-send-email-hollis_blanchard@mentor.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

2 files changed, 24 insertions, 16 deletions

diff --git a/memory.c b/memory.c
index 9f5c4584d1..07a5236eb4 100644
--- a/memory.c
+++ b/memory.c
@@ -386,6 +386,14 @@ static hwaddr memory_region_to_absolute_addr(MemoryRegion *mr, hwaddr offset)
     return abs_addr;
 }
 
+static int get_cpu_index(void)
+{
+    if (current_cpu) {
+        return current_cpu->cpu_index;
+    }
+    return -1;
+}
+
 static MemTxResult memory_region_oldmmio_read_accessor(MemoryRegion *mr,
                                                        hwaddr addr,
                                                        uint64_t *value,
@@ -398,10 +406,10 @@ static MemTxResult memory_region_oldmmio_read_accessor(MemoryRegion *mr,
 
     tmp = mr->ops->old_mmio.read[ctz32(size)](mr->opaque, addr);
     if (mr->subpage) {
-        trace_memory_region_subpage_read(mr, addr, tmp, size);
+        trace_memory_region_subpage_read(get_cpu_index(), mr, addr, tmp, size);
     } else if (TRACE_MEMORY_REGION_OPS_READ_ENABLED) {
         hwaddr abs_addr = memory_region_to_absolute_addr(mr, addr);
-        trace_memory_region_ops_read(mr, abs_addr, tmp, size);
+        trace_memory_region_ops_read(get_cpu_index(), mr, abs_addr, tmp, size);
     }
     *value |= (tmp & mask) << shift;
     return MEMTX_OK;
@@ -419,10 +427,10 @@ static MemTxResult  memory_region_read_accessor(MemoryRegion *mr,
 
     tmp = mr->ops->read(mr->opaque, addr, size);
     if (mr->subpage) {
-        trace_memory_region_subpage_read(mr, addr, tmp, size);
+        trace_memory_region_subpage_read(get_cpu_index(), mr, addr, tmp, size);
     } else if (TRACE_MEMORY_REGION_OPS_READ_ENABLED) {
         hwaddr abs_addr = memory_region_to_absolute_addr(mr, addr);
-        trace_memory_region_ops_read(mr, abs_addr, tmp, size);
+        trace_memory_region_ops_read(get_cpu_index(), mr, abs_addr, tmp, size);
     }
     *value |= (tmp & mask) << shift;
     return MEMTX_OK;
@@ -441,10 +449,10 @@ static MemTxResult memory_region_read_with_attrs_accessor(MemoryRegion *mr,
 
     r = mr->ops->read_with_attrs(mr->opaque, addr, &tmp, size, attrs);
     if (mr->subpage) {
-        trace_memory_region_subpage_read(mr, addr, tmp, size);
+        trace_memory_region_subpage_read(get_cpu_index(), mr, addr, tmp, size);
     } else if (TRACE_MEMORY_REGION_OPS_READ_ENABLED) {
         hwaddr abs_addr = memory_region_to_absolute_addr(mr, addr);
-        trace_memory_region_ops_read(mr, abs_addr, tmp, size);
+        trace_memory_region_ops_read(get_cpu_index(), mr, abs_addr, tmp, size);
     }
     *value |= (tmp & mask) << shift;
     return r;
@@ -462,10 +470,10 @@ static MemTxResult memory_region_oldmmio_write_accessor(MemoryRegion *mr,
 
     tmp = (*value >> shift) & mask;
     if (mr->subpage) {
-        trace_memory_region_subpage_write(mr, addr, tmp, size);
+        trace_memory_region_subpage_write(get_cpu_index(), mr, addr, tmp, size);
     } else if (TRACE_MEMORY_REGION_OPS_WRITE_ENABLED) {
         hwaddr abs_addr = memory_region_to_absolute_addr(mr, addr);
-        trace_memory_region_ops_write(mr, abs_addr, tmp, size);
+        trace_memory_region_ops_write(get_cpu_index(), mr, abs_addr, tmp, size);
     }
     mr->ops->old_mmio.write[ctz32(size)](mr->opaque, addr, tmp);
     return MEMTX_OK;
@@ -483,10 +491,10 @@ static MemTxResult memory_region_write_accessor(MemoryRegion *mr,
 
     tmp = (*value >> shift) & mask;
     if (mr->subpage) {
-        trace_memory_region_subpage_write(mr, addr, tmp, size);
+        trace_memory_region_subpage_write(get_cpu_index(), mr, addr, tmp, size);
     } else if (TRACE_MEMORY_REGION_OPS_WRITE_ENABLED) {
         hwaddr abs_addr = memory_region_to_absolute_addr(mr, addr);
-        trace_memory_region_ops_write(mr, abs_addr, tmp, size);
+        trace_memory_region_ops_write(get_cpu_index(), mr, abs_addr, tmp, size);
     }
     mr->ops->write(mr->opaque, addr, tmp, size);
     return MEMTX_OK;
@@ -504,10 +512,10 @@ static MemTxResult memory_region_write_with_attrs_accessor(MemoryRegion *mr,
 
     tmp = (*value >> shift) & mask;
     if (mr->subpage) {
-        trace_memory_region_subpage_write(mr, addr, tmp, size);
+        trace_memory_region_subpage_write(get_cpu_index(), mr, addr, tmp, size);
     } else if (TRACE_MEMORY_REGION_OPS_WRITE_ENABLED) {
         hwaddr abs_addr = memory_region_to_absolute_addr(mr, addr);
-        trace_memory_region_ops_write(mr, abs_addr, tmp, size);
+        trace_memory_region_ops_write(get_cpu_index(), mr, abs_addr, tmp, size);
     }
     return mr->ops->write_with_attrs(mr->opaque, addr, tmp, size, attrs);
 }
diff --git a/trace-events b/trace-events
index 6fba6cc474..a9f33fba8c 100644
--- a/trace-events
+++ b/trace-events
@@ -1620,10 +1620,10 @@ disable exec_tb_exit(void *next_tb, unsigned int flags) "tb:%p flags=%x"
 translate_block(void *tb, uintptr_t pc, uint8_t *tb_code) "tb:%p, pc:0x%"PRIxPTR", tb_code:%p"
 
 # memory.c
-memory_region_ops_read(void *mr, uint64_t addr, uint64_t value, unsigned size) "mr %p addr %#"PRIx64" value %#"PRIx64" size %u"
-memory_region_ops_write(void *mr, uint64_t addr, uint64_t value, unsigned size) "mr %p addr %#"PRIx64" value %#"PRIx64" size %u"
-memory_region_subpage_read(void *mr, uint64_t offset, uint64_t value, unsigned size) "mr %p offset %#"PRIx64" value %#"PRIx64" size %u"
-memory_region_subpage_write(void *mr, uint64_t offset, uint64_t value, unsigned size) "mr %p offset %#"PRIx64" value %#"PRIx64" size %u"
+memory_region_ops_read(int cpu_index, void *mr, uint64_t addr, uint64_t value, unsigned size) "cpu %d mr %p addr %#"PRIx64" value %#"PRIx64" size %u"
+memory_region_ops_write(int cpu_index, void *mr, uint64_t addr, uint64_t value, unsigned size) "cpu %d mr %p addr %#"PRIx64" value %#"PRIx64" size %u"
+memory_region_subpage_read(int cpu_index, void *mr, uint64_t offset, uint64_t value, unsigned size) "cpu %d mr %p offset %#"PRIx64" value %#"PRIx64" size %u"
+memory_region_subpage_write(int cpu_index, void *mr, uint64_t offset, uint64_t value, unsigned size) "cpu %d mr %p offset %#"PRIx64" value %#"PRIx64" size %u"
 
 # qom/object.c
 object_dynamic_cast_assert(const char *type, const char *target, const char *file, int line, const char *func) "%s->%s (%s:%d:%s)"