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Date: Wed, 26 Jan 2022 01:13:37 +0000
From: Phillip Potter <phil@...lpotter.co.uk>
To: Pavel Skripkin <paskripkin@...il.com>
Cc: gregkh@...uxfoundation.org, dan.carpenter@...cle.com,
Larry.Finger@...inger.net, straube.linux@...il.com,
martin@...ser.cx, linux-staging@...ts.linux.dev,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH 06/10] staging: r8188eu: remove DBG_88E calls from
os_dep/ioctl_linux.c
On Tue, Jan 25, 2022 at 10:03:06PM +0300, Pavel Skripkin wrote:
> Hi Phillip,
>
> On 1/25/22 01:44, Phillip Potter wrote:
> > Remove all DBG_88E calls from os_dep/ioctl_linux.c, as they do not
> > conform to kernel coding standards and are superfluous. Also restructure
> > where appropriate to remove no longer needed code left behind by removal
> > of these calls. This will allow the eventual removal of the DBG_88E macro
> > itself.
> >
> > Signed-off-by: Phillip Potter <phil@...lpotter.co.uk>
> > ---
>
> [code snip]
>
> > @@ -3746,7 +3541,6 @@ static int rtw_dbg_port(struct net_device *dev,
> > u32 write_num = extra_arg;
> > int i;
> > - u16 final;
> > struct xmit_frame *xmit_frame;
> > xmit_frame = rtw_IOL_accquire_xmit_frame(padapter);
> > @@ -3760,11 +3554,7 @@ static int rtw_dbg_port(struct net_device *dev,
> > if (rtl8188e_IOL_exec_cmds_sync(padapter, xmit_frame, 5000, 0) != _SUCCESS)
> > ret = -EPERM;
> > - final = rtw_read16(padapter, reg);
> > - if (start_value + write_num - 1 == final)
> > - DBG_88E("continuous IOL_CMD_WW_REG to 0x%x %u times Success, start:%u, final:%u\n", reg, write_num, start_value, final);
> > - else
> > - DBG_88E("continuous IOL_CMD_WW_REG to 0x%x %u times Fail, start:%u, final:%u\n", reg, write_num, start_value, final);
> > + rtw_read16(padapter, reg);
> > }
> > break;
>
> I see, that you somewhere removes reads and somewhere leaves them. What's
> the difference? I saw, that one of the places has the comment, that asks not
> to remove the read, but others do not have such comment
>
> I can point to few places in 2 and 4 patches where you have removed reads.
>
>
>
> [code snip]
>
> > @@ -4014,16 +3664,8 @@ static int rtw_dbg_port(struct net_device *dev,
> > {
> > u32 odm_flag;
> > - if (0xf == extra_arg) {
> > + if (extra_arg == 0xf) {
> > GetHalDefVar8188EUsb(padapter, HAL_DEF_DBG_DM_FUNC, &odm_flag);
> > - DBG_88E(" === DMFlag(0x%08x) ===\n", odm_flag);
> > - DBG_88E("extra_arg = 0 - disable all dynamic func\n");
> > - DBG_88E("extra_arg = 1 - disable DIG- BIT(0)\n");
> > - DBG_88E("extra_arg = 2 - disable High power - BIT(1)\n");
> > - DBG_88E("extra_arg = 3 - disable tx power tracking - BIT(2)\n");
> > - DBG_88E("extra_arg = 4 - disable BT coexistence - BIT(3)\n");
> > - DBG_88E("extra_arg = 5 - disable antenna diversity - BIT(4)\n");
> > - DBG_88E("extra_arg = 6 - enable all dynamic func\n");
> > } else {
> > /* extra_arg = 0 - disable all dynamic func
> > extra_arg = 1 - disable DIG
> > @@ -4032,51 +3674,17 @@ static int rtw_dbg_port(struct net_device *dev,
> > */
> > SetHalDefVar8188EUsb(padapter, HAL_DEF_DBG_DM_FUNC, &extra_arg);
> > GetHalDefVar8188EUsb(padapter, HAL_DEF_DBG_DM_FUNC, &odm_flag);
> > - DBG_88E(" === DMFlag(0x%08x) ===\n", odm_flag);
> > }
> > }
> > break;
>
> Is odm_flag needed now? Seems like it was used only for printing random
> debug info
You're right, it can probably go :-)
>
> > case 0xfd:
> > rtw_write8(padapter, 0xc50, arg);
> > - DBG_88E("wr(0xc50) = 0x%x\n", rtw_read8(padapter, 0xc50));
> > rtw_write8(padapter, 0xc58, arg);
> > - DBG_88E("wr(0xc58) = 0x%x\n", rtw_read8(padapter, 0xc58));
> > - break;
> > - case 0xfe:
> > - DBG_88E("rd(0xc50) = 0x%x\n", rtw_read8(padapter, 0xc50));
> > - DBG_88E("rd(0xc58) = 0x%x\n", rtw_read8(padapter, 0xc58));
> > - break;
> > - case 0xff:
> > - DBG_88E("dbg(0x210) = 0x%x\n", rtw_read32(padapter, 0x210));
> > - DBG_88E("dbg(0x608) = 0x%x\n", rtw_read32(padapter, 0x608));
> > - DBG_88E("dbg(0x280) = 0x%x\n", rtw_read32(padapter, 0x280));
> > - DBG_88E("dbg(0x284) = 0x%x\n", rtw_read32(padapter, 0x284));
> > - DBG_88E("dbg(0x288) = 0x%x\n", rtw_read32(padapter, 0x288));
> > -
> > - DBG_88E("dbg(0x664) = 0x%x\n", rtw_read32(padapter, 0x664));
> > -
> > - DBG_88E("\n");
> > -
> > - DBG_88E("dbg(0x430) = 0x%x\n", rtw_read32(padapter, 0x430));
> > - DBG_88E("dbg(0x438) = 0x%x\n", rtw_read32(padapter, 0x438));
> > -
> > - DBG_88E("dbg(0x440) = 0x%x\n", rtw_read32(padapter, 0x440));
> > -
> > - DBG_88E("dbg(0x458) = 0x%x\n", rtw_read32(padapter, 0x458));
> > -
> > - DBG_88E("dbg(0x484) = 0x%x\n", rtw_read32(padapter, 0x484));
> > - DBG_88E("dbg(0x488) = 0x%x\n", rtw_read32(padapter, 0x488));
> > -
> > - DBG_88E("dbg(0x444) = 0x%x\n", rtw_read32(padapter, 0x444));
> > - DBG_88E("dbg(0x448) = 0x%x\n", rtw_read32(padapter, 0x448));
> > - DBG_88E("dbg(0x44c) = 0x%x\n", rtw_read32(padapter, 0x44c));
> > - DBG_88E("dbg(0x450) = 0x%x\n", rtw_read32(padapter, 0x450));
> > break;
> > }
>
> And here you also removes the reads. I guess, some kind of magic pattern is
> used
>
So these calls are macro arguments, they would never be executed under
normal circumstances anyway, unless the rtw_debug kernel module was
passed in as 5 or more - it is 1 by default. The DBG_88E macro would
expand during preprocessing phase to (for example):
do {
if (5 <= GlobalDebugLevel)
pr_info("R8188EU: " "dbg(0x450) = 0x%x\n", rtw_read32(padapter, 0x450));
} while (0)
As this is never executed under normal circumstances anyway, I would say
calls like these are therefore safe to remove. Happy to be convinced
though :-) Many thanks.
Regards,
Phil
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