| Message ID | 20241030131416.3091954-1-colin.i.king@gmail.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Ping-Ke Shih |
| Headers | show |
| Series | [next] wifi: rtw89: 8852a: remove redundant else statement | expand |
On 10/30/2024 6:14 AM, Colin Ian King wrote: > The cascaded if statements covers all 16 bit values in the comparisons > of dgain and the last else statement is not reachable and hence > dead code. Remove it. > > Signed-off-by: Colin Ian King <colin.i.king@gmail.com> > --- > drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c b/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c > index 9db8713ac99b..f3568c4d0af6 100644 > --- a/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c > +++ b/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c > @@ -2248,8 +2248,6 @@ static s8 _dpk_dgain_mapping(struct rtw89_dev *rtwdev, u16 dgain) > offset = -9; > else if (dgain <= 0x155) should you drop the test and unconditionally return -12 here? > offset = -12; > - else > - offset = 0x0; > > return offset; > }
Jeff Johnson <quic_jjohnson@quicinc.com> wrote: > On 10/30/2024 6:14 AM, Colin Ian King wrote: > > The cascaded if statements covers all 16 bit values in the comparisons > > of dgain and the last else statement is not reachable and hence > > dead code. Remove it. > > > > Signed-off-by: Colin Ian King <colin.i.king@gmail.com> > > --- > > drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c | 2 -- > > 1 file changed, 2 deletions(-) > > > > diff --git a/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c b/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c > > index 9db8713ac99b..f3568c4d0af6 100644 > > --- a/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c > > +++ b/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c > > @@ -2248,8 +2248,6 @@ static s8 _dpk_dgain_mapping(struct rtw89_dev *rtwdev, u16 dgain) > > offset = -9; > > else if (dgain <= 0x155) > > should you drop the test and unconditionally return -12 here? Agree +1. People don't suspect the else case at first glance. > > > offset = -12; > > - else > > - offset = 0x0; > > > > return offset; > > } >
Hi Colin,
kernel test robot noticed the following build warnings:
[auto build test WARNING on wireless-next/main]
[also build test WARNING on wireless/main linus/master v6.12-rc5 next-20241101]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Colin-Ian-King/wifi-rtw89-8852a-remove-redundant-else-statement/20241030-211507
base: https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next.git main
patch link: https://lore.kernel.org/r/20241030131416.3091954-1-colin.i.king%40gmail.com
patch subject: [PATCH][next] wifi: rtw89: 8852a: remove redundant else statement
config: um-allmodconfig (https://download.01.org/0day-ci/archive/20241102/202411020209.qamp5h6r-lkp@intel.com/config)
compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 639a7ac648f1e50ccd2556e17d401c04f9cce625)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241102/202411020209.qamp5h6r-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202411020209.qamp5h6r-lkp@intel.com/
All warnings (new ones prefixed by >>):
In file included from drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c:5:
In file included from drivers/net/wireless/realtek/rtw89/coex.h:8:
In file included from drivers/net/wireless/realtek/rtw89/core.h:12:
In file included from include/linux/iopoll.h:14:
In file included from include/linux/io.h:14:
In file included from arch/um/include/asm/io.h:24:
include/asm-generic/io.h:548:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
548 | val = __raw_readb(PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:561:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
561 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
| ^
In file included from drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c:5:
In file included from drivers/net/wireless/realtek/rtw89/coex.h:8:
In file included from drivers/net/wireless/realtek/rtw89/core.h:12:
In file included from include/linux/iopoll.h:14:
In file included from include/linux/io.h:14:
In file included from arch/um/include/asm/io.h:24:
include/asm-generic/io.h:574:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
574 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
| ^
In file included from drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c:5:
In file included from drivers/net/wireless/realtek/rtw89/coex.h:8:
In file included from drivers/net/wireless/realtek/rtw89/core.h:12:
In file included from include/linux/iopoll.h:14:
In file included from include/linux/io.h:14:
In file included from arch/um/include/asm/io.h:24:
include/asm-generic/io.h:585:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
585 | __raw_writeb(value, PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:595:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
595 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:605:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
605 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:693:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
693 | readsb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:701:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
701 | readsw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:709:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
709 | readsl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:718:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
718 | writesb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:727:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
727 | writesw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:736:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
736 | writesl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
In file included from drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c:5:
In file included from drivers/net/wireless/realtek/rtw89/coex.h:8:
In file included from drivers/net/wireless/realtek/rtw89/core.h:14:
In file included from include/net/mac80211.h:18:
In file included from include/linux/if_ether.h:19:
In file included from include/linux/skbuff.h:17:
In file included from include/linux/bvec.h:10:
In file included from include/linux/highmem.h:8:
In file included from include/linux/cacheflush.h:5:
In file included from arch/um/include/asm/cacheflush.h:4:
In file included from arch/um/include/asm/tlbflush.h:9:
In file included from include/linux/mm.h:2213:
include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
| ~~~~~~~~~~~ ^ ~~~
>> drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c:2249:11: warning: variable 'offset' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
2249 | else if (dgain <= 0x155)
| ^~~~~~~~~~~~~~
drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c:2252:9: note: uninitialized use occurs here
2252 | return offset;
| ^~~~~~
drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c:2249:7: note: remove the 'if' if its condition is always true
2249 | else if (dgain <= 0x155)
| ^~~~~~~~~~~~~~~~~~~
2250 | offset = -12;
drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c:2235:11: note: initialize the variable 'offset' to silence this warning
2235 | s8 offset;
| ^
| = '\0'
14 warnings generated.
Kconfig warnings: (for reference only)
WARNING: unmet direct dependencies detected for GET_FREE_REGION
Depends on [n]: SPARSEMEM [=n]
Selected by [m]:
- RESOURCE_KUNIT_TEST [=m] && RUNTIME_TESTING_MENU [=y] && KUNIT [=m]
vim +2249 drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2232
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2233 static s8 _dpk_dgain_mapping(struct rtw89_dev *rtwdev, u16 dgain)
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2234 {
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2235 s8 offset;
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2236
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2237 if (dgain >= 0x783)
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2238 offset = 0x6;
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2239 else if (dgain <= 0x782 && dgain >= 0x551)
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2240 offset = 0x3;
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2241 else if (dgain <= 0x550 && dgain >= 0x3c4)
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2242 offset = 0x0;
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2243 else if (dgain <= 0x3c3 && dgain >= 0x2aa)
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2244 offset = -3;
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2245 else if (dgain <= 0x2a9 && dgain >= 0x1e3)
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2246 offset = -6;
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2247 else if (dgain <= 0x1e2 && dgain >= 0x156)
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2248 offset = -9;
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 @2249 else if (dgain <= 0x155)
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2250 offset = -12;
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2251
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2252 return offset;
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2253 }
e3ec7017f6a20d Ping-Ke Shih 2021-10-11 2254
diff --git a/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c b/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c index 9db8713ac99b..f3568c4d0af6 100644 --- a/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c +++ b/drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c @@ -2248,8 +2248,6 @@ static s8 _dpk_dgain_mapping(struct rtw89_dev *rtwdev, u16 dgain) offset = -9; else if (dgain <= 0x155) offset = -12; - else - offset = 0x0; return offset; }
The cascaded if statements covers all 16 bit values in the comparisons of dgain and the last else statement is not reachable and hence dead code. Remove it. Signed-off-by: Colin Ian King <colin.i.king@gmail.com> --- drivers/net/wireless/realtek/rtw89/rtw8852a_rfk.c | 2 -- 1 file changed, 2 deletions(-)