Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932396Ab1FBIuz (ORCPT ); Thu, 2 Jun 2011 04:50:55 -0400 Received: from mail-wy0-f174.google.com ([74.125.82.174]:42544 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752317Ab1FBIuv convert rfc822-to-8bit (ORCPT ); Thu, 2 Jun 2011 04:50:51 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=DQrQblX1SHKald3/vtQ2wLweSeE+iWzpFax2PTZlpP8Z14Di6kHXqZ7ko82qRPiHiT io4m2HsMScdZUZmmIZISfQkb6X3HK9QsZ2YNjAdjvJApBuVFv/nlgeNBRkQwxNDXYyf8 lz/2gjGnW0Udf1fBNzJEk/qp/oT5yPisoOGO4= MIME-Version: 1.0 In-Reply-To: <46950A08-9300-4649-A38D-88829035DFC2@dilger.ca> References: <1306939009-11283-1-git-send-email-akinobu.mita@gmail.com> <46950A08-9300-4649-A38D-88829035DFC2@dilger.ca> Date: Thu, 2 Jun 2011 11:50:49 +0300 Message-ID: Subject: Re: [PATCH v2 1/2] ext4: arrange ext4_*_bit() macros From: Amir Goldstein To: Andreas Dilger Cc: Akinobu Mita , linux-kernel@vger.kernel.org, "Theodore Ts'o" , linux-ext4@vger.kernel.org, Yongqiang Yang Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10378 Lines: 235 On Wed, Jun 1, 2011 at 11:49 PM, Andreas Dilger wrote: > On 2011-06-01, at 8:36 AM, Akinobu Mita wrote: >> - remove unused ext4_{set,clear}_bit_atomic and ext4_find_first_zero_bit FYI, one of the snapshot patches (snapshot_exclude_bitmap.patch) uses ext4_set_bit_atomic() to set bits in the exclude bitmap when moving blocks to snapshot file. Since moving blocks is not done in allocation context, there is no buddy/group lock held while manipulating the exclude bitmap. So I would appreciate if this specific macro will not be removed. Thanks, Yongqiang , for pointing that out. >> - rename ext4_{set,clear}_bit to ext4_test_and_{set,clear}_bit >> - reintroduce ext4_{set,clear}_bit for __{set,clear}_bit_le >> >> This changes ext4_{set,clear}_bit safely, because if someone uses >> these macros without noticing the change, new ext4_{set,clear}_bit >> don't have return value and causes compiler errors where the return >> value is used. > > I don't think it makes sense to change all of the ext4_set_bit() calls that > don't check the return code to use ext4_test_and_set_bit(), just to return > them back to ext4_set_bit() in the next patch. > > If you want to do this in separate steps, and maintain git bisect working, > then it would be more clear to have two patches: > > Patch #1: Add new ext4_test_and_set_bit() macro > #define ext4_test_and_set_bit ? ? ? ? ? __test_and_set_bit_le > {change ext4_set_bit() calls that check return to ?ext4_test_and_set_bit()} > > Patch #2: Change ext4_set_bit() to not return old bit > #define ext4_set_bit ? ? ? ? ? ? ? ? ? ?__set_bit_le > {nothing else changes} > > Alternately, you could just leave the calls that do not check the return > value as ext4_set_bit() and have only a single patch. > > >> Signed-off-by: Akinobu Mita >> Cc: "Theodore Ts'o" >> Cc: Andreas Dilger >> Cc: linux-ext4@vger.kernel.org >> --- >> v2: rewritten to keep ext4_*_bit() macros >> >> fs/ext4/balloc.c ?| ? ?8 ++++---- >> fs/ext4/ext4.h ? ?| ? ?9 ++++----- >> fs/ext4/ialloc.c ?| ? ?9 ++++----- >> fs/ext4/mballoc.c | ? ?4 ++-- >> fs/ext4/resize.c ?| ? 12 ++++++------ >> 5 files changed, 20 insertions(+), 22 deletions(-) >> >> diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c >> index 264f694..b6747e4 100644 >> --- a/fs/ext4/balloc.c >> +++ b/fs/ext4/balloc.c >> @@ -144,7 +144,7 @@ unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, >> ? ? ? ? ? ? ? int flex_bg = 0; >> >> ? ? ? ? ? ? ? for (bit = 0; bit < bit_max; bit++) >> - ? ? ? ? ? ? ? ? ? ? ext4_set_bit(bit, bh->b_data); >> + ? ? ? ? ? ? ? ? ? ? ext4_test_and_set_bit(bit, bh->b_data); >> >> ? ? ? ? ? ? ? start = ext4_group_first_block_no(sb, block_group); >> >> @@ -155,18 +155,18 @@ unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, >> ? ? ? ? ? ? ? /* Set bits for block and inode bitmaps, and inode table */ >> ? ? ? ? ? ? ? tmp = ext4_block_bitmap(sb, gdp); >> ? ? ? ? ? ? ? if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) >> - ? ? ? ? ? ? ? ? ? ? ext4_set_bit(tmp - start, bh->b_data); >> + ? ? ? ? ? ? ? ? ? ? ext4_test_and_set_bit(tmp - start, bh->b_data); >> >> ? ? ? ? ? ? ? tmp = ext4_inode_bitmap(sb, gdp); >> ? ? ? ? ? ? ? if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) >> - ? ? ? ? ? ? ? ? ? ? ext4_set_bit(tmp - start, bh->b_data); >> + ? ? ? ? ? ? ? ? ? ? ext4_test_and_set_bit(tmp - start, bh->b_data); >> >> ? ? ? ? ? ? ? tmp = ext4_inode_table(sb, gdp); >> ? ? ? ? ? ? ? for (; tmp < ext4_inode_table(sb, gdp) + >> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? sbi->s_itb_per_group; tmp++) { >> ? ? ? ? ? ? ? ? ? ? ? if (!flex_bg || >> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ext4_block_in_group(sb, tmp, block_group)) >> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ext4_set_bit(tmp - start, bh->b_data); >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ext4_test_and_set_bit(tmp - start, bh->b_data); >> ? ? ? ? ? ? ? } >> ? ? ? ? ? ? ? /* >> ? ? ? ? ? ? ? ?* Also if the number of blocks within the group is >> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h >> index 1921392..04db84f 100644 >> --- a/fs/ext4/ext4.h >> +++ b/fs/ext4/ext4.h >> @@ -930,12 +930,11 @@ struct ext4_inode_info { >> #define test_opt2(sb, opt) ? ? ? ? ? ?(EXT4_SB(sb)->s_mount_opt2 & \ >> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?EXT4_MOUNT2_##opt) >> >> -#define ext4_set_bit ? ? ? ? ? ? ? ? __test_and_set_bit_le >> -#define ext4_set_bit_atomic ? ? ? ? ?ext2_set_bit_atomic >> -#define ext4_clear_bit ? ? ? ? ? ? ? ? ? ? ? __test_and_clear_bit_le >> -#define ext4_clear_bit_atomic ? ? ? ? ? ? ? ?ext2_clear_bit_atomic >> +#define ext4_test_and_set_bit ? ? ? ? ? ? ? ?__test_and_set_bit_le >> +#define ext4_set_bit ? ? ? ? ? ? ? ? __set_bit_le >> +#define ext4_test_and_clear_bit ? ? ? ? ? ? ?__test_and_clear_bit_le >> +#define ext4_clear_bit ? ? ? ? ? ? ? ? ? ? ? __clear_bit_le >> #define ext4_test_bit ? ? ? ? ? ? ? ? test_bit_le >> -#define ext4_find_first_zero_bit ? ? find_first_zero_bit_le >> #define ext4_find_next_zero_bit ? ? ? ? ? ? ? find_next_zero_bit_le >> #define ext4_find_next_bit ? ? ? ? ? ?find_next_bit_le >> >> diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c >> index 21bb2f6..90bef6b 100644 >> --- a/fs/ext4/ialloc.c >> +++ b/fs/ext4/ialloc.c >> @@ -59,7 +59,7 @@ void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap) >> >> ? ? ? ext4_debug("mark end bits +%d through +%d used\n", start_bit, end_bit); >> ? ? ? for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++) >> - ? ? ? ? ? ? ext4_set_bit(i, bitmap); >> + ? ? ? ? ? ? ext4_test_and_set_bit(i, bitmap); >> ? ? ? if (i < end_bit) >> ? ? ? ? ? ? ? memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3); >> } >> @@ -252,7 +252,7 @@ void ext4_free_inode(handle_t *handle, struct inode *inode) >> ? ? ? ? ? ? ? fatal = ext4_journal_get_write_access(handle, bh2); >> ? ? ? } >> ? ? ? ext4_lock_group(sb, block_group); >> - ? ? cleared = ext4_clear_bit(bit, bitmap_bh->b_data); >> + ? ? cleared = ext4_test_and_clear_bit(bit, bitmap_bh->b_data); >> ? ? ? if (fatal || !cleared) { >> ? ? ? ? ? ? ? ext4_unlock_group(sb, block_group); >> ? ? ? ? ? ? ? goto out; >> @@ -729,7 +729,7 @@ static int ext4_claim_inode(struct super_block *sb, >> ? ? ? ?*/ >> ? ? ? down_read(&grp->alloc_sem); >> ? ? ? ext4_lock_group(sb, group); >> - ? ? if (ext4_set_bit(ino, inode_bitmap_bh->b_data)) { >> + ? ? if (ext4_test_and_set_bit(ino, inode_bitmap_bh->b_data)) { >> ? ? ? ? ? ? ? /* not a free inode */ >> ? ? ? ? ? ? ? retval = 1; >> ? ? ? ? ? ? ? goto err_ret; >> @@ -884,8 +884,7 @@ got_group: >> ? ? ? ? ? ? ? ? ? ? ? goto fail; >> >> repeat_in_this_group: >> - ? ? ? ? ? ? ino = ext4_find_next_zero_bit((unsigned long *) >> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? inode_bitmap_bh->b_data, >> + ? ? ? ? ? ? ino = ext4_find_next_zero_bit(inode_bitmap_bh->b_data, >> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? EXT4_INODES_PER_GROUP(sb), ino); >> >> ? ? ? ? ? ? ? if (ino < EXT4_INODES_PER_GROUP(sb)) { >> diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c >> index 859f2ae..b423adf 100644 >> --- a/fs/ext4/mballoc.c >> +++ b/fs/ext4/mballoc.c >> @@ -384,13 +384,13 @@ static inline int mb_test_bit(int bit, void *addr) >> static inline void mb_set_bit(int bit, void *addr) >> { >> ? ? ? addr = mb_correct_addr_and_bit(&bit, addr); >> - ? ? ext4_set_bit(bit, addr); >> + ? ? ext4_test_and_set_bit(bit, addr); >> } >> >> static inline void mb_clear_bit(int bit, void *addr) >> { >> ? ? ? addr = mb_correct_addr_and_bit(&bit, addr); >> - ? ? ext4_clear_bit(bit, addr); >> + ? ? ext4_test_and_clear_bit(bit, addr); >> } >> >> static inline int mb_find_next_zero_bit(void *addr, int max, int start) >> diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c >> index 80bbc9c..cc40963 100644 >> --- a/fs/ext4/resize.c >> +++ b/fs/ext4/resize.c >> @@ -194,7 +194,7 @@ static int setup_new_group_blocks(struct super_block *sb, >> >> ? ? ? if (ext4_bg_has_super(sb, input->group)) { >> ? ? ? ? ? ? ? ext4_debug("mark backup superblock %#04llx (+0)\n", start); >> - ? ? ? ? ? ? ext4_set_bit(0, bh->b_data); >> + ? ? ? ? ? ? ext4_test_and_set_bit(0, bh->b_data); >> ? ? ? } >> >> ? ? ? /* Copy all of the GDT blocks into the backup in this group */ >> @@ -225,7 +225,7 @@ static int setup_new_group_blocks(struct super_block *sb, >> ? ? ? ? ? ? ? ? ? ? ? brelse(gdb); >> ? ? ? ? ? ? ? ? ? ? ? goto exit_bh; >> ? ? ? ? ? ? ? } >> - ? ? ? ? ? ? ext4_set_bit(bit, bh->b_data); >> + ? ? ? ? ? ? ext4_test_and_set_bit(bit, bh->b_data); >> ? ? ? ? ? ? ? brelse(gdb); >> ? ? ? } >> >> @@ -237,14 +237,14 @@ static int setup_new_group_blocks(struct super_block *sb, >> ? ? ? if (err) >> ? ? ? ? ? ? ? goto exit_bh; >> ? ? ? for (i = 0, bit = gdblocks + 1; i < reserved_gdb; i++, bit++) >> - ? ? ? ? ? ? ext4_set_bit(bit, bh->b_data); >> + ? ? ? ? ? ? ext4_test_and_set_bit(bit, bh->b_data); >> >> ? ? ? ext4_debug("mark block bitmap %#04llx (+%llu)\n", input->block_bitmap, >> ? ? ? ? ? ? ? ? ?input->block_bitmap - start); >> - ? ? ext4_set_bit(input->block_bitmap - start, bh->b_data); >> + ? ? ext4_test_and_set_bit(input->block_bitmap - start, bh->b_data); >> ? ? ? ext4_debug("mark inode bitmap %#04llx (+%llu)\n", input->inode_bitmap, >> ? ? ? ? ? ? ? ? ?input->inode_bitmap - start); >> - ? ? ext4_set_bit(input->inode_bitmap - start, bh->b_data); >> + ? ? ext4_test_and_set_bit(input->inode_bitmap - start, bh->b_data); >> >> ? ? ? /* Zero out all of the inode table blocks */ >> ? ? ? block = input->inode_table; >> @@ -255,7 +255,7 @@ static int setup_new_group_blocks(struct super_block *sb, >> ? ? ? ? ? ? ? goto exit_bh; >> ? ? ? for (i = 0, bit = input->inode_table - start; >> ? ? ? ? ? ?i < sbi->s_itb_per_group; i++, bit++) >> - ? ? ? ? ? ? ext4_set_bit(bit, bh->b_data); >> + ? ? ? ? ? ? ext4_test_and_set_bit(bit, bh->b_data); >> >> ? ? ? if ((err = extend_or_restart_transaction(handle, 2, bh))) >> ? ? ? ? ? ? ? goto exit_bh; >> -- >> 1.7.4.4 >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at ?http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/