Re: [PATCH] state: backend_bucket_direct: add debug prints on read/write

[Johannes Zink]

Hi Ahmad,

thanks for your patch.
On 7/28/23 15:31, Ahmad Fatoum wrote:
We already have debug prints for the circular backend to help see how
much data is read/written for each bucket. Add similar debugging info
for the direct backend as well. Example with stride size of 2048 and
44 bytes for the variable set:

   barebox@board:/ state -l
   state: Read state from 0 length 68
   state: Read state from 2048 length 68
   state: Read state from 4096 length 68

   barebox@board:/ state -s
   state: Written state to offset 0 length 68 data length 60
   state: Written state to offset 2048 length 68 data length 60
   state: Written state to offset 4096 length 68 data length 60

Signed-off-by: Ahmad Fatoum <a.fat...@pengutronix.de>
---
  common/state/backend_bucket_direct.c | 14 +++++++++++++-
  1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/common/state/backend_bucket_direct.c 
b/common/state/backend_bucket_direct.c
index f06e14277862..03c752d6fe41 100644
--- a/common/state/backend_bucket_direct.c
+++ b/common/state/backend_bucket_direct.c
@@ -52,7 +52,7 @@ static int state_backend_bucket_direct_read(struct 
state_backend_storage_bucket
        struct state_backend_storage_bucket_direct *direct =
            get_bucket_direct(bucket);
        struct state_backend_storage_bucket_direct_meta meta;
-       uint32_t read_len;
+       uint32_t read_len, header_len = 0;
        void *buf;
        int ret;
  
@@ -72,6 +72,8 @@ static int state_backend_bucket_direct_read(struct state_backend_storage_bucket
                        return -EINVAL;
  
  		}
+
+               header_len = sizeof(meta);
        } else {
                if (meta.magic != ~0 && !!meta.magic)
                        bucket->wrong_magic = 1;
@@ -87,12 +89,16 @@ static int state_backend_bucket_direct_read(struct 
state_backend_storage_bucket
                                -errno);
                        return -errno;
                }
+
        }
  
  	buf = xmalloc(read_len);
        if (!buf)
                return -ENOMEM;
  
+	dev_dbg(direct->dev, "Read state from %lld length %d\n", (long long) direct->offset,
+               header_len + read_len);
+

maybe this could use the same message format as for writing (i.e. total length 
and data length pointed out separately)?

Best regards
Johannes

        ret = read_full(direct->fd, buf, read_len);
        if (ret < 0) {
                dev_err(direct->dev, "Failed to read from file, %d\n", ret);
@@ -112,6 +118,7 @@ static int state_backend_bucket_direct_write(struct 
state_backend_storage_bucket
  {
        struct state_backend_storage_bucket_direct *direct =
            get_bucket_direct(bucket);
+       size_t header_len = 0;
        int ret;
        struct state_backend_storage_bucket_direct_meta meta;
  
@@ -129,6 +136,8 @@ static int state_backend_bucket_direct_write(struct state_backend_storage_bucket
                        dev_err(direct->dev, "Failed to write metadata to file, 
%d\n", ret);
                        return ret;
                }
+
+               header_len = sizeof(meta);
        } else {
                if (!IS_ENABLED(CONFIG_STATE_BACKWARD_COMPATIBLE)) {
                        dev_dbg(direct->dev, "Too small stride size: must skip 
metadata! Increase stride size\n");
@@ -148,6 +157,9 @@ static int state_backend_bucket_direct_write(struct 
state_backend_storage_bucket
                return ret;
        }
  
+	dev_dbg(direct->dev, "Written state to offset %lld length %zu data length %zu\n",
+               (long long)direct->offset, len + header_len, len);
+
        return 0;
  }
  

--
Pengutronix e.K.                | Johannes Zink                  |
Steuerwalder Str. 21            | https://www.pengutronix.de/    |
31137 Hildesheim, Germany       | Phone: +49-5121-206917-0       |
Amtsgericht Hildesheim, HRA 2686| Fax:   +49-5121-206917-5555    |