Re: [PATCH] scsi: megaraid: cleanup formatting of megaraid

Tom Rix <trix@xxxxxxxxxx> · Thu, 27 Jan 2022 16:32:37 -0800





On 1/27/22 2:47 PM, Nick Desaulniers wrote:
+ Miguel (the clang-format maintainer), Joe (checkpatch maintainer)
These criticisms are worth reviewing.

On Thu, Jan 27, 2022 at 2:38 PM Finn Thain <fthain@xxxxxxxxxxxxxx> wrote:

On Thu, 27 Jan 2022, trix@xxxxxxxxxx wrote:

From: Tom Rix <trix@xxxxxxxxxx>

checkpatch reports several hundred formatting errors. Run these files
through clang-format and knock off some of them.

That method seems like a good recipe for endless churn unless checkpatch
and clang-format really agree about these style rules.

Why use checkpatch to assess code style, if we could simply diff the
existing source with the output from clang-format... but it seems that
clang-format harms readability, makes indentation errors and uses
inconsistent style rules. Some examples:

Problems with clang-format should be fixed, I'll take a look.

I was reviewing this file for another issue and could not get past how 
horredously bad it was and really did not want to manually fix the 400+ 
formatting errors.  I will drop this patch and use the use these files 
to verify the .clang-format .

Tom


  static unsigned short int max_sectors_per_io = MAX_SECTORS_PER_IO;
  module_param(max_sectors_per_io, ushort, 0);
-MODULE_PARM_DESC(max_sectors_per_io, "Maximum number of sectors per I/O request (default=MAX_SECTORS_PER_IO=128)");
-
+MODULE_PARM_DESC(
+     max_sectors_per_io,
+     "Maximum number of sectors per I/O request (default=MAX_SECTORS_PER_IO=128)");

  static unsigned short int max_mbox_busy_wait = MBOX_BUSY_WAIT;
  module_param(max_mbox_busy_wait, ushort, 0);
-MODULE_PARM_DESC(max_mbox_busy_wait, "Maximum wait for mailbox in microseconds if busy (default=MBOX_BUSY_WAIT=10)");
+MODULE_PARM_DESC(
+     max_mbox_busy_wait,
+     "Maximum wait for mailbox in microseconds if busy (default=MBOX_BUSY_WAIT=10)");

This code is longer for no real improvement.

  /*
   * The File Operations structure for the serial/ioctl interface of the driver
   */
  static const struct file_operations megadev_fops = {
-     .owner          = THIS_MODULE,
-     .unlocked_ioctl = megadev_unlocked_ioctl,
-     .open           = megadev_open,
-     .llseek         = noop_llseek,
+     .owner = THIS_MODULE,
+     .unlocked_ioctl = megadev_unlocked_ioctl,
+     .open = megadev_open,
+     .llseek = noop_llseek,
  };

  /*
Readability loss.

-             prod_info_dma_handle = dma_map_single(&adapter->dev->dev,
-                                                   (void *)&adapter->product_info,
-                                                   sizeof(mega_product_info),
-                                                   DMA_FROM_DEVICE);
+             prod_info_dma_handle = dma_map_single(
+                     &adapter->dev->dev, (void *)&adapter->product_info,
+                     sizeof(mega_product_info), DMA_FROM_DEVICE);

Note the orphaned first parameter and odd indentation.

  static DEF_SCSI_QCMD(megaraid_queue)

-/**
+     /**
   * mega_allocate_scb()
   * @adapter: pointer to our soft state
   * @cmd: scsi command from the mid-layer
Indentation error.

@@ -418,15 +409,14 @@ static DEF_SCSI_QCMD(megaraid_queue)
   * Allocate a SCB structure. This is the central structure for controller
   * commands.
   */
-static inline scb_t *
-mega_allocate_scb(adapter_t *adapter, struct scsi_cmnd *cmd)
+     static inline scb_t *mega_allocate_scb(adapter_t *adapter,
+                                            struct scsi_cmnd *cmd)
  {
       struct list_head *head = &adapter->free_list;
Same.

@@ -586,26 +568,25 @@ mega_build_cmd(adapter_t *adapter, struct scsi_cmnd *cmd, int *busy)

               ldrv_num = mega_get_ldrv_num(adapter, cmd, channel);

-
               max_ldrv_num = (adapter->flag & BOARD_40LD) ?
-                     MAX_LOGICAL_DRIVES_40LD : MAX_LOGICAL_DRIVES_8LD;
+                                    MAX_LOGICAL_DRIVES_40LD :
+                                          MAX_LOGICAL_DRIVES_8LD;

Churn, if not readability loss. Note the indentation change here is
inconsistent with the indentation change noted above.

                        * 6-byte READ(0x08) or WRITE(0x0A) cdb
                        */
-                     if( cmd->cmd_len == 6 ) {
-                             mbox->m_out.numsectors = (u32) cmd->cmnd[4];
-                             mbox->m_out.lba =
-                                     ((u32)cmd->cmnd[1] << 16) |
-                                     ((u32)cmd->cmnd[2] << 8) |
-                                     (u32)cmd->cmnd[3];
+                     if (cmd->cmd_len == 6) {
+                             mbox->m_out.numsectors = (u32)cmd->cmnd[4];
+                             mbox->m_out.lba = ((u32)cmd->cmnd[1] << 16) |
+                                               ((u32)cmd->cmnd[2] << 8) |
+                                               (u32)cmd->cmnd[3];

                               mbox->m_out.lba &= 0x1FFFFF;

Here, the orphaned term is moved up, next to the =. And yet,

                       /* Calculate Scatter-Gather info */
-                     mbox->m_out.numsgelements = mega_build_sglist(adapter, scb,
-                                     (u32 *)&mbox->m_out.xferaddr, &seg);
+                     mbox->m_out.numsgelements =
+                             mega_build_sglist(adapter, scb,
+                                               (u32 *)&mbox->m_out.xferaddr,
+                                               &seg);

                       return scb;

... here the first term is moved down and orphaned, which is another
inconsistency.









