diff mbox series

btrfs: Simplify setup_nodes_for_search

Message ID 20201112111622.784178-1-nborisov@suse.com (mailing list archive)
State New, archived
Headers show
Series btrfs: Simplify setup_nodes_for_search | expand

Commit Message

Nikolay Borisov Nov. 12, 2020, 11:16 a.m. UTC
The function is needlessly convoluted. Fix that by:

* Removing redundant sret variable definition in both if arms.

* Replace the again/done labels with direct return statements, the
function is short enough and doesn't do anything special upon exit.

* Remove BUG_ON on split_node returning a positive number - it can't
  happen as split_node returns either 0 or a negative error code.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
---
 fs/btrfs/ctree.c | 28 +++++++---------------------
 1 file changed, 7 insertions(+), 21 deletions(-)

Comments

Johannes Thumshirn Nov. 12, 2020, 12:17 p.m. UTC | #1
Can't spot any errors,
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
kernel test robot Nov. 13, 2020, 3:30 a.m. UTC | #2
Hi Nikolay,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on kdave/for-next]
[also build test WARNING on next-20201112]
[cannot apply to v5.10-rc3]
[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]

url:    https://github.com/0day-ci/linux/commits/Nikolay-Borisov/btrfs-Simplify-setup_nodes_for_search/20201112-191847
base:   https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git for-next
config: riscv-randconfig-r011-20201112 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project a7b65741441556d295079fc4f2391d99fd1c1111)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install riscv cross compiling tool for clang build
        # apt-get install binutils-riscv64-linux-gnu
        # https://github.com/0day-ci/linux/commit/aea2237f4b88d91fc8ad6469b205ff6ada2fcf55
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Nikolay-Borisov/btrfs-Simplify-setup_nodes_for_search/20201112-191847
        git checkout aea2237f4b88d91fc8ad6469b205ff6ada2fcf55
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

                                                                                        ^
   include/uapi/linux/byteorder/little_endian.h:36:51: note: expanded from macro '__le16_to_cpu'
   #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
                                                     ^
   In file included from fs/btrfs/ctree.c:10:
   In file included from fs/btrfs/ctree.h:11:
   In file included from include/linux/highmem.h:10:
   In file included from include/linux/hardirq.h:10:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:13:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:149:
   include/asm-generic/io.h:572:9: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           return inl(addr);
                  ^~~~~~~~~
   arch/riscv/include/asm/io.h:57:76: note: expanded from macro 'inl'
   #define inl(c)          ({ u32 __v; __io_pbr(); __v = readl_cpu((void*)(PCI_IOBASE + (c))); __io_par(__v); __v; })
                                                                           ~~~~~~~~~~ ^
   arch/riscv/include/asm/mmio.h:89:76: note: expanded from macro 'readl_cpu'
   #define readl_cpu(c)            ({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; })
                                                                                        ^
   include/uapi/linux/byteorder/little_endian.h:34:51: note: expanded from macro '__le32_to_cpu'
   #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
                                                     ^
   In file included from fs/btrfs/ctree.c:10:
   In file included from fs/btrfs/ctree.h:11:
   In file included from include/linux/highmem.h:10:
   In file included from include/linux/hardirq.h:10:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:13:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:149:
   include/asm-generic/io.h:580:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           outb(value, addr);
           ^~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:59:68: note: expanded from macro 'outb'
   #define outb(v,c)       ({ __io_pbw(); writeb_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); })
                                                                 ~~~~~~~~~~ ^
   arch/riscv/include/asm/mmio.h:91:52: note: expanded from macro 'writeb_cpu'
   #define writeb_cpu(v, c)        ((void)__raw_writeb((v), (c)))
                                                             ^
   In file included from fs/btrfs/ctree.c:10:
   In file included from fs/btrfs/ctree.h:11:
   In file included from include/linux/highmem.h:10:
   In file included from include/linux/hardirq.h:10:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:13:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:149:
   include/asm-generic/io.h:588:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           outw(value, addr);
           ^~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:60:68: note: expanded from macro 'outw'
   #define outw(v,c)       ({ __io_pbw(); writew_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); })
                                                                 ~~~~~~~~~~ ^
   arch/riscv/include/asm/mmio.h:92:76: note: expanded from macro 'writew_cpu'
   #define writew_cpu(v, c)        ((void)__raw_writew((__force u16)cpu_to_le16(v), (c)))
                                                                                     ^
   In file included from fs/btrfs/ctree.c:10:
   In file included from fs/btrfs/ctree.h:11:
   In file included from include/linux/highmem.h:10:
   In file included from include/linux/hardirq.h:10:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:13:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:149:
   include/asm-generic/io.h:596:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           outl(value, addr);
           ^~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:61:68: note: expanded from macro 'outl'
   #define outl(v,c)       ({ __io_pbw(); writel_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); })
                                                                 ~~~~~~~~~~ ^
   arch/riscv/include/asm/mmio.h:93:76: note: expanded from macro 'writel_cpu'
   #define writel_cpu(v, c)        ((void)__raw_writel((__force u32)cpu_to_le32(v), (c)))
                                                                                     ^
   In file included from fs/btrfs/ctree.c:10:
   In file included from fs/btrfs/ctree.h:11:
   In file included from include/linux/highmem.h:10:
   In file included from include/linux/hardirq.h:10:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:13:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:149:
   include/asm-generic/io.h:1005:55: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port;
                                                     ~~~~~~~~~~ ^
   fs/btrfs/ctree.c:2408:13: warning: variable 'ret' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
           } else if (ins_len < 0 && btrfs_header_nritems(b) <
                      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   fs/btrfs/ctree.c:2429:9: note: uninitialized use occurs here
           return ret;
                  ^~~
   fs/btrfs/ctree.c:2408:9: note: remove the 'if' if its condition is always true
           } else if (ins_len < 0 && btrfs_header_nritems(b) <
                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> fs/btrfs/ctree.c:2408:13: warning: variable 'ret' is used uninitialized whenever '&&' condition is false [-Wsometimes-uninitialized]
           } else if (ins_len < 0 && btrfs_header_nritems(b) <
                      ^~~~~~~~~~~
   fs/btrfs/ctree.c:2429:9: note: uninitialized use occurs here
           return ret;
                  ^~~
   fs/btrfs/ctree.c:2408:13: note: remove the '&&' if its condition is always true
           } else if (ins_len < 0 && btrfs_header_nritems(b) <
                      ^~~~~~~~~~~~~~
   fs/btrfs/ctree.c:2393:9: note: initialize the variable 'ret' to silence this warning
           int ret;
                  ^
                   = 0
   9 warnings generated.

vim +2408 fs/btrfs/ctree.c

c8c42864f619363 Chris Mason     2009-04-03  2376  
c8c42864f619363 Chris Mason     2009-04-03  2377  /*
c8c42864f619363 Chris Mason     2009-04-03  2378   * helper function for btrfs_search_slot.  This does all of the checks
c8c42864f619363 Chris Mason     2009-04-03  2379   * for node-level blocks and does any balancing required based on
c8c42864f619363 Chris Mason     2009-04-03  2380   * the ins_len.
c8c42864f619363 Chris Mason     2009-04-03  2381   *
c8c42864f619363 Chris Mason     2009-04-03  2382   * If no extra work was required, zero is returned.  If we had to
c8c42864f619363 Chris Mason     2009-04-03  2383   * drop the path, -EAGAIN is returned and btrfs_search_slot must
c8c42864f619363 Chris Mason     2009-04-03  2384   * start over
c8c42864f619363 Chris Mason     2009-04-03  2385   */
c8c42864f619363 Chris Mason     2009-04-03  2386  static int
c8c42864f619363 Chris Mason     2009-04-03  2387  setup_nodes_for_search(struct btrfs_trans_handle *trans,
c8c42864f619363 Chris Mason     2009-04-03  2388  		       struct btrfs_root *root, struct btrfs_path *p,
bd681513fa6f2ff Chris Mason     2011-07-16  2389  		       struct extent_buffer *b, int level, int ins_len,
bd681513fa6f2ff Chris Mason     2011-07-16  2390  		       int *write_lock_level)
c8c42864f619363 Chris Mason     2009-04-03  2391  {
0b246afa62b0cf5 Jeff Mahoney    2016-06-22  2392  	struct btrfs_fs_info *fs_info = root->fs_info;
c8c42864f619363 Chris Mason     2009-04-03  2393  	int ret;
0b246afa62b0cf5 Jeff Mahoney    2016-06-22  2394  
c8c42864f619363 Chris Mason     2009-04-03  2395  	if ((p->search_for_split || ins_len > 0) && btrfs_header_nritems(b) >=
0b246afa62b0cf5 Jeff Mahoney    2016-06-22  2396  	    BTRFS_NODEPTRS_PER_BLOCK(fs_info) - 3) {
c8c42864f619363 Chris Mason     2009-04-03  2397  
bd681513fa6f2ff Chris Mason     2011-07-16  2398  		if (*write_lock_level < level + 1) {
bd681513fa6f2ff Chris Mason     2011-07-16  2399  			*write_lock_level = level + 1;
bd681513fa6f2ff Chris Mason     2011-07-16  2400  			btrfs_release_path(p);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2401  			return -EAGAIN;
bd681513fa6f2ff Chris Mason     2011-07-16  2402  		}
bd681513fa6f2ff Chris Mason     2011-07-16  2403  
480b65236526f4c Josef Bacik     2020-11-05  2404  		reada_for_balance(p, level);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2405  		ret = split_node(trans, root, p, level);
c8c42864f619363 Chris Mason     2009-04-03  2406  
c8c42864f619363 Chris Mason     2009-04-03  2407  		b = p->nodes[level];
c8c42864f619363 Chris Mason     2009-04-03 @2408  	} else if (ins_len < 0 && btrfs_header_nritems(b) <
0b246afa62b0cf5 Jeff Mahoney    2016-06-22  2409  		   BTRFS_NODEPTRS_PER_BLOCK(fs_info) / 2) {
c8c42864f619363 Chris Mason     2009-04-03  2410  
bd681513fa6f2ff Chris Mason     2011-07-16  2411  		if (*write_lock_level < level + 1) {
bd681513fa6f2ff Chris Mason     2011-07-16  2412  			*write_lock_level = level + 1;
bd681513fa6f2ff Chris Mason     2011-07-16  2413  			btrfs_release_path(p);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2414  			return -EAGAIN;
bd681513fa6f2ff Chris Mason     2011-07-16  2415  		}
bd681513fa6f2ff Chris Mason     2011-07-16  2416  
480b65236526f4c Josef Bacik     2020-11-05  2417  		reada_for_balance(p, level);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2418  		ret = balance_level(trans, root, p, level);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2419  		if (ret)
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2420  			return ret;
c8c42864f619363 Chris Mason     2009-04-03  2421  
c8c42864f619363 Chris Mason     2009-04-03  2422  		b = p->nodes[level];
c8c42864f619363 Chris Mason     2009-04-03  2423  		if (!b) {
b3b4aa74b58bded David Sterba    2011-04-21  2424  			btrfs_release_path(p);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2425  			return -EAGAIN;
c8c42864f619363 Chris Mason     2009-04-03  2426  		}
c8c42864f619363 Chris Mason     2009-04-03  2427  		BUG_ON(btrfs_header_nritems(b) == 1);
c8c42864f619363 Chris Mason     2009-04-03  2428  	}
c8c42864f619363 Chris Mason     2009-04-03  2429  	return ret;
c8c42864f619363 Chris Mason     2009-04-03  2430  }
c8c42864f619363 Chris Mason     2009-04-03  2431  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
kernel test robot Nov. 13, 2020, 5:06 a.m. UTC | #3
Hi Nikolay,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on kdave/for-next]
[also build test WARNING on next-20201112]
[cannot apply to btrfs/next v5.10-rc3]
[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]

url:    https://github.com/0day-ci/linux/commits/Nikolay-Borisov/btrfs-Simplify-setup_nodes_for_search/20201112-191847
base:   https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git for-next
config: riscv-randconfig-r014-20201112 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project a7b65741441556d295079fc4f2391d99fd1c1111)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install riscv cross compiling tool for clang build
        # apt-get install binutils-riscv64-linux-gnu
        # https://github.com/0day-ci/linux/commit/aea2237f4b88d91fc8ad6469b205ff6ada2fcf55
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Nikolay-Borisov/btrfs-Simplify-setup_nodes_for_search/20201112-191847
        git checkout aea2237f4b88d91fc8ad6469b205ff6ada2fcf55
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   In file included from arch/riscv/include/asm/io.h:149:
   include/asm-generic/io.h:564:9: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           return inw(addr);
                  ^~~~~~~~~
   arch/riscv/include/asm/io.h:56:76: note: expanded from macro 'inw'
   #define inw(c)          ({ u16 __v; __io_pbr(); __v = readw_cpu((void*)(PCI_IOBASE + (c))); __io_par(__v); __v; })
                                                                           ~~~~~~~~~~ ^
   arch/riscv/include/asm/mmio.h:88:76: note: expanded from macro 'readw_cpu'
   #define readw_cpu(c)            ({ u16 __r = le16_to_cpu((__force __le16)__raw_readw(c)); __r; })
                                                                                        ^
   include/uapi/linux/byteorder/little_endian.h:36:51: note: expanded from macro '__le16_to_cpu'
   #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
                                                     ^
   In file included from fs/btrfs/ctree.c:10:
   In file included from fs/btrfs/ctree.h:11:
   In file included from include/linux/highmem.h:10:
   In file included from include/linux/hardirq.h:10:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:13:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:149:
   include/asm-generic/io.h:572:9: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           return inl(addr);
                  ^~~~~~~~~
   arch/riscv/include/asm/io.h:57:76: note: expanded from macro 'inl'
   #define inl(c)          ({ u32 __v; __io_pbr(); __v = readl_cpu((void*)(PCI_IOBASE + (c))); __io_par(__v); __v; })
                                                                           ~~~~~~~~~~ ^
   arch/riscv/include/asm/mmio.h:89:76: note: expanded from macro 'readl_cpu'
   #define readl_cpu(c)            ({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; })
                                                                                        ^
   include/uapi/linux/byteorder/little_endian.h:34:51: note: expanded from macro '__le32_to_cpu'
   #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
                                                     ^
   In file included from fs/btrfs/ctree.c:10:
   In file included from fs/btrfs/ctree.h:11:
   In file included from include/linux/highmem.h:10:
   In file included from include/linux/hardirq.h:10:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:13:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:149:
   include/asm-generic/io.h:580:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           outb(value, addr);
           ^~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:59:68: note: expanded from macro 'outb'
   #define outb(v,c)       ({ __io_pbw(); writeb_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); })
                                                                 ~~~~~~~~~~ ^
   arch/riscv/include/asm/mmio.h:91:52: note: expanded from macro 'writeb_cpu'
   #define writeb_cpu(v, c)        ((void)__raw_writeb((v), (c)))
                                                             ^
   In file included from fs/btrfs/ctree.c:10:
   In file included from fs/btrfs/ctree.h:11:
   In file included from include/linux/highmem.h:10:
   In file included from include/linux/hardirq.h:10:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:13:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:149:
   include/asm-generic/io.h:588:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           outw(value, addr);
           ^~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:60:68: note: expanded from macro 'outw'
   #define outw(v,c)       ({ __io_pbw(); writew_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); })
                                                                 ~~~~~~~~~~ ^
   arch/riscv/include/asm/mmio.h:92:76: note: expanded from macro 'writew_cpu'
   #define writew_cpu(v, c)        ((void)__raw_writew((__force u16)cpu_to_le16(v), (c)))
                                                                                     ^
   In file included from fs/btrfs/ctree.c:10:
   In file included from fs/btrfs/ctree.h:11:
   In file included from include/linux/highmem.h:10:
   In file included from include/linux/hardirq.h:10:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:13:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:149:
   include/asm-generic/io.h:596:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           outl(value, addr);
           ^~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:61:68: note: expanded from macro 'outl'
   #define outl(v,c)       ({ __io_pbw(); writel_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); })
                                                                 ~~~~~~~~~~ ^
   arch/riscv/include/asm/mmio.h:93:76: note: expanded from macro 'writel_cpu'
   #define writel_cpu(v, c)        ((void)__raw_writel((__force u32)cpu_to_le32(v), (c)))
                                                                                     ^
   In file included from fs/btrfs/ctree.c:10:
   In file included from fs/btrfs/ctree.h:11:
   In file included from include/linux/highmem.h:10:
   In file included from include/linux/hardirq.h:10:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:13:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:149:
   include/asm-generic/io.h:1005:55: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port;
                                                     ~~~~~~~~~~ ^
>> fs/btrfs/ctree.c:2408:13: warning: variable 'ret' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
           } else if (ins_len < 0 && btrfs_header_nritems(b) <
                      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   fs/btrfs/ctree.c:2429:9: note: uninitialized use occurs here
           return ret;
                  ^~~
   fs/btrfs/ctree.c:2408:9: note: remove the 'if' if its condition is always true
           } else if (ins_len < 0 && btrfs_header_nritems(b) <
                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> fs/btrfs/ctree.c:2408:13: warning: variable 'ret' is used uninitialized whenever '&&' condition is false [-Wsometimes-uninitialized]
           } else if (ins_len < 0 && btrfs_header_nritems(b) <
                      ^~~~~~~~~~~
   fs/btrfs/ctree.c:2429:9: note: uninitialized use occurs here
           return ret;
                  ^~~
   fs/btrfs/ctree.c:2408:13: note: remove the '&&' if its condition is always true
           } else if (ins_len < 0 && btrfs_header_nritems(b) <
                      ^~~~~~~~~~~~~~
   fs/btrfs/ctree.c:2393:9: note: initialize the variable 'ret' to silence this warning
           int ret;
                  ^
                   = 0
   9 warnings generated.

vim +2408 fs/btrfs/ctree.c

c8c42864f619363 Chris Mason     2009-04-03  2376  
c8c42864f619363 Chris Mason     2009-04-03  2377  /*
c8c42864f619363 Chris Mason     2009-04-03  2378   * helper function for btrfs_search_slot.  This does all of the checks
c8c42864f619363 Chris Mason     2009-04-03  2379   * for node-level blocks and does any balancing required based on
c8c42864f619363 Chris Mason     2009-04-03  2380   * the ins_len.
c8c42864f619363 Chris Mason     2009-04-03  2381   *
c8c42864f619363 Chris Mason     2009-04-03  2382   * If no extra work was required, zero is returned.  If we had to
c8c42864f619363 Chris Mason     2009-04-03  2383   * drop the path, -EAGAIN is returned and btrfs_search_slot must
c8c42864f619363 Chris Mason     2009-04-03  2384   * start over
c8c42864f619363 Chris Mason     2009-04-03  2385   */
c8c42864f619363 Chris Mason     2009-04-03  2386  static int
c8c42864f619363 Chris Mason     2009-04-03  2387  setup_nodes_for_search(struct btrfs_trans_handle *trans,
c8c42864f619363 Chris Mason     2009-04-03  2388  		       struct btrfs_root *root, struct btrfs_path *p,
bd681513fa6f2ff Chris Mason     2011-07-16  2389  		       struct extent_buffer *b, int level, int ins_len,
bd681513fa6f2ff Chris Mason     2011-07-16  2390  		       int *write_lock_level)
c8c42864f619363 Chris Mason     2009-04-03  2391  {
0b246afa62b0cf5 Jeff Mahoney    2016-06-22  2392  	struct btrfs_fs_info *fs_info = root->fs_info;
c8c42864f619363 Chris Mason     2009-04-03  2393  	int ret;
0b246afa62b0cf5 Jeff Mahoney    2016-06-22  2394  
c8c42864f619363 Chris Mason     2009-04-03  2395  	if ((p->search_for_split || ins_len > 0) && btrfs_header_nritems(b) >=
0b246afa62b0cf5 Jeff Mahoney    2016-06-22  2396  	    BTRFS_NODEPTRS_PER_BLOCK(fs_info) - 3) {
c8c42864f619363 Chris Mason     2009-04-03  2397  
bd681513fa6f2ff Chris Mason     2011-07-16  2398  		if (*write_lock_level < level + 1) {
bd681513fa6f2ff Chris Mason     2011-07-16  2399  			*write_lock_level = level + 1;
bd681513fa6f2ff Chris Mason     2011-07-16  2400  			btrfs_release_path(p);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2401  			return -EAGAIN;
bd681513fa6f2ff Chris Mason     2011-07-16  2402  		}
bd681513fa6f2ff Chris Mason     2011-07-16  2403  
480b65236526f4c Josef Bacik     2020-11-05  2404  		reada_for_balance(p, level);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2405  		ret = split_node(trans, root, p, level);
c8c42864f619363 Chris Mason     2009-04-03  2406  
c8c42864f619363 Chris Mason     2009-04-03  2407  		b = p->nodes[level];
c8c42864f619363 Chris Mason     2009-04-03 @2408  	} else if (ins_len < 0 && btrfs_header_nritems(b) <
0b246afa62b0cf5 Jeff Mahoney    2016-06-22  2409  		   BTRFS_NODEPTRS_PER_BLOCK(fs_info) / 2) {
c8c42864f619363 Chris Mason     2009-04-03  2410  
bd681513fa6f2ff Chris Mason     2011-07-16  2411  		if (*write_lock_level < level + 1) {
bd681513fa6f2ff Chris Mason     2011-07-16  2412  			*write_lock_level = level + 1;
bd681513fa6f2ff Chris Mason     2011-07-16  2413  			btrfs_release_path(p);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2414  			return -EAGAIN;
bd681513fa6f2ff Chris Mason     2011-07-16  2415  		}
bd681513fa6f2ff Chris Mason     2011-07-16  2416  
480b65236526f4c Josef Bacik     2020-11-05  2417  		reada_for_balance(p, level);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2418  		ret = balance_level(trans, root, p, level);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2419  		if (ret)
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2420  			return ret;
c8c42864f619363 Chris Mason     2009-04-03  2421  
c8c42864f619363 Chris Mason     2009-04-03  2422  		b = p->nodes[level];
c8c42864f619363 Chris Mason     2009-04-03  2423  		if (!b) {
b3b4aa74b58bded David Sterba    2011-04-21  2424  			btrfs_release_path(p);
aea2237f4b88d91 Nikolay Borisov 2020-11-12  2425  			return -EAGAIN;
c8c42864f619363 Chris Mason     2009-04-03  2426  		}
c8c42864f619363 Chris Mason     2009-04-03  2427  		BUG_ON(btrfs_header_nritems(b) == 1);
c8c42864f619363 Chris Mason     2009-04-03  2428  	}
c8c42864f619363 Chris Mason     2009-04-03  2429  	return ret;
c8c42864f619363 Chris Mason     2009-04-03  2430  }
c8c42864f619363 Chris Mason     2009-04-03  2431  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 892b467347a3..6c309dfee3f5 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -2394,52 +2394,38 @@  setup_nodes_for_search(struct btrfs_trans_handle *trans,
 
 	if ((p->search_for_split || ins_len > 0) && btrfs_header_nritems(b) >=
 	    BTRFS_NODEPTRS_PER_BLOCK(fs_info) - 3) {
-		int sret;
 
 		if (*write_lock_level < level + 1) {
 			*write_lock_level = level + 1;
 			btrfs_release_path(p);
-			goto again;
+			return -EAGAIN;
 		}
 
 		reada_for_balance(p, level);
-		sret = split_node(trans, root, p, level);
+		ret = split_node(trans, root, p, level);
 
-		BUG_ON(sret > 0);
-		if (sret) {
-			ret = sret;
-			goto done;
-		}
 		b = p->nodes[level];
 	} else if (ins_len < 0 && btrfs_header_nritems(b) <
 		   BTRFS_NODEPTRS_PER_BLOCK(fs_info) / 2) {
-		int sret;
 
 		if (*write_lock_level < level + 1) {
 			*write_lock_level = level + 1;
 			btrfs_release_path(p);
-			goto again;
+			return -EAGAIN;
 		}
 
 		reada_for_balance(p, level);
-		sret = balance_level(trans, root, p, level);
+		ret = balance_level(trans, root, p, level);
+		if (ret)
+			return ret;
 
-		if (sret) {
-			ret = sret;
-			goto done;
-		}
 		b = p->nodes[level];
 		if (!b) {
 			btrfs_release_path(p);
-			goto again;
+			return -EAGAIN;
 		}
 		BUG_ON(btrfs_header_nritems(b) == 1);
 	}
-	return 0;
-
-again:
-	ret = -EAGAIN;
-done:
 	return ret;
 }