[Qemu-devel] [PATCH v3 1/7] hw/nvram/fw_cfg: Add trace events

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

Add trace events to dump the key content.

Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
v1 -> v3:
- moved static fw_cfg_wellknown_keys[] in key_name()
- split trace_key_name() (can return "unknown")
  from key_name() (can return NULL)

Since changes from v1 are trivial, keep S-o-b tags.
---
 hw/nvram/fw_cfg.c     | 63 ++++++++++++++++++++++++++++++++++++++++++-
 hw/nvram/trace-events |  7 ++++-
 2 files changed, 68 insertions(+), 2 deletions(-)

diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
index 5c3a46ce6f2..d374a970fea 100644
--- a/hw/nvram/fw_cfg.c
+++ b/hw/nvram/fw_cfg.c
@@ -60,6 +60,62 @@ struct FWCfgEntry {
     FWCfgWriteCallback write_cb;
 };
 
+/**
+ * key_name:
+ *
+ * @key: The uint16 selector key.
+ *
+ * Returns: The stringified name if the selector refers to a well-known
+ *          numerically defined item, or NULL on key lookup failure.
+ */
+static const char *key_name(uint16_t key)
+{
+    static const char *fw_cfg_wellknown_keys[FW_CFG_FILE_FIRST] = {
+        [FW_CFG_SIGNATURE] = "signature",
+        [FW_CFG_ID] = "id",
+        [FW_CFG_UUID] = "uuid",
+        [FW_CFG_RAM_SIZE] = "ram_size",
+        [FW_CFG_NOGRAPHIC] = "nographic",
+        [FW_CFG_NB_CPUS] = "nb_cpus",
+        [FW_CFG_MACHINE_ID] = "machine_id",
+        [FW_CFG_KERNEL_ADDR] = "kernel_addr",
+        [FW_CFG_KERNEL_SIZE] = "kernel_size",
+        [FW_CFG_KERNEL_CMDLINE] = "kernel_cmdline",
+        [FW_CFG_INITRD_ADDR] = "initrd_addr",
+        [FW_CFG_INITRD_SIZE] = "initdr_size",
+        [FW_CFG_BOOT_DEVICE] = "boot_device",
+        [FW_CFG_NUMA] = "numa",
+        [FW_CFG_BOOT_MENU] = "boot_menu",
+        [FW_CFG_MAX_CPUS] = "max_cpus",
+        [FW_CFG_KERNEL_ENTRY] = "kernel_entry",
+        [FW_CFG_KERNEL_DATA] = "kernel_data",
+        [FW_CFG_INITRD_DATA] = "initrd_data",
+        [FW_CFG_CMDLINE_ADDR] = "cmdline_addr",
+        [FW_CFG_CMDLINE_SIZE] = "cmdline_size",
+        [FW_CFG_CMDLINE_DATA] = "cmdline_data",
+        [FW_CFG_SETUP_ADDR] = "setup_addr",
+        [FW_CFG_SETUP_SIZE] = "setup_size",
+        [FW_CFG_SETUP_DATA] = "setup_data",
+        [FW_CFG_FILE_DIR] = "file_dir",
+    };
+
+    if (key & FW_CFG_ARCH_LOCAL) {
+        return NULL;
+    }
+    if (key < FW_CFG_FILE_FIRST) {
+        return fw_cfg_wellknown_keys[key];
+    }
+
+    return NULL;
+}
+
+static inline const char *trace_key_name(uint16_t key)
+{
+    const char *name = key_name(key);
+
+    return name ? name : "unknown";
+}
+
 #define JPG_FILE 0
 #define BMP_FILE 1
 
@@ -233,7 +289,7 @@ static int fw_cfg_select(FWCfgState *s, uint16_t key)
         }
     }
 
-    trace_fw_cfg_select(s, key, ret);
+    trace_fw_cfg_select(s, key, trace_key_name(key), ret);
     return ret;
 }
 
@@ -616,6 +672,7 @@ static void *fw_cfg_modify_bytes_read(FWCfgState *s, uint16_t key,
 
 void fw_cfg_add_bytes(FWCfgState *s, uint16_t key, void *data, size_t len)
 {
+    trace_fw_cfg_add_bytes(key, trace_key_name(key), len);
     fw_cfg_add_bytes_callback(s, key, NULL, NULL, NULL, data, len, true);
 }
 
@@ -623,6 +680,7 @@ void fw_cfg_add_string(FWCfgState *s, uint16_t key, const char *value)
 {
     size_t sz = strlen(value) + 1;
 
+    trace_fw_cfg_add_string(key, trace_key_name(key), value);
     fw_cfg_add_bytes(s, key, g_memdup(value, sz), sz);
 }
 
@@ -632,6 +690,7 @@ void fw_cfg_add_i16(FWCfgState *s, uint16_t key, uint16_t value)
 
     copy = g_malloc(sizeof(value));
     *copy = cpu_to_le16(value);
+    trace_fw_cfg_add_i16(key, trace_key_name(key), value);
     fw_cfg_add_bytes(s, key, copy, sizeof(value));
 }
 
@@ -651,6 +710,7 @@ void fw_cfg_add_i32(FWCfgState *s, uint16_t key, uint32_t value)
 
     copy = g_malloc(sizeof(value));
     *copy = cpu_to_le32(value);
+    trace_fw_cfg_add_i32(key, trace_key_name(key), value);
     fw_cfg_add_bytes(s, key, copy, sizeof(value));
 }
 
@@ -660,6 +720,7 @@ void fw_cfg_add_i64(FWCfgState *s, uint16_t key, uint64_t value)
 
     copy = g_malloc(sizeof(value));
     *copy = cpu_to_le64(value);
+    trace_fw_cfg_add_i64(key, trace_key_name(key), value);
     fw_cfg_add_bytes(s, key, copy, sizeof(value));
 }
 
diff --git a/hw/nvram/trace-events b/hw/nvram/trace-events
index e191991e2a8..0dea9260ce1 100644
--- a/hw/nvram/trace-events
+++ b/hw/nvram/trace-events
@@ -5,6 +5,11 @@ nvram_read(uint32_t addr, uint32_t ret) "read addr %d: 0x%02x"
 nvram_write(uint32_t addr, uint32_t old, uint32_t val) "write addr %d: 0x%02x -> 0x%02x"
 
 # fw_cfg.c
-fw_cfg_select(void *s, uint16_t key, int ret) "%p key %d = %d"
+fw_cfg_select(void *s, uint16_t key_value, const char *key_name, int ret) "%p key 0x%04" PRIx16 " '%s', ret: %d"
 fw_cfg_read(void *s, uint64_t ret) "%p = 0x%"PRIx64
+fw_cfg_add_bytes(uint16_t key_value, const char *key_name, size_t len) "key 0x%04" PRIx16 " '%s', %zu bytes"
 fw_cfg_add_file(void *s, int index, char *name, size_t len) "%p #%d: %s (%zd bytes)"
+fw_cfg_add_string(uint16_t key_value, const char *key_name, const char *value) "key 0x%04" PRIx16 " '%s', value '%s'"
+fw_cfg_add_i16(uint16_t key_value, const char *key_name, uint16_t value) "key 0x%04" PRIx16 " '%s', value 0x%" PRIx16
+fw_cfg_add_i32(uint16_t key_value, const char *key_name, uint32_t value) "key 0x%04" PRIx16 " '%s', value 0x%" PRIx32
+fw_cfg_add_i64(uint16_t key_value, const char *key_name, uint64_t value) "key 0x%04" PRIx16 " '%s', value 0x%" PRIx64
-- 
2.20.1