diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2019-07-08 14:40:09 +0200 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2019-09-09 14:58:58 +0200 |
| commit | 8ddc319706e5ca201a128e3f2477938d7f174ca8 (patch) | |
| tree | e20a4e6ee2aeb65637296365fd8e74fa39f84680 /fs | |
| parent | 99fccf33c203f63ea10e611c505a26686b0b8738 (diff) | |
btrfs: reduce stack usage for btrfsic_process_written_block
btrfsic_process_written_block() cals btrfsic_process_metablock(),
which has a fairly large stack usage due to the btrfsic_stack_frame
variable. It also calls btrfsic_test_for_metadata(), which now
needs several hundreds of bytes for its SHASH_DESC_ON_STACK().
In some configurations, we end up with both functions on the
same stack, and gcc warns about the excessive stack usage that
might cause the available stack space to run out:
fs/btrfs/check-integrity.c:1743:13: error: stack frame size of 1152 bytes in function 'btrfsic_process_written_block' [-Werror,-Wframe-larger-than=]
Marking both child functions as noinline_for_stack helps because
this guarantees that the large variables are not on the same
stack frame.
Fixes: d5178578bcd4 ("btrfs: directly call into crypto framework for checksumming")
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/check-integrity.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c index 81a9731959a9..0b52ab4cb964 100644 --- a/fs/btrfs/check-integrity.c +++ b/fs/btrfs/check-integrity.c @@ -940,7 +940,7 @@ static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf) kfree(sf); } -static int btrfsic_process_metablock( +static noinline_for_stack int btrfsic_process_metablock( struct btrfsic_state *state, struct btrfsic_block *const first_block, struct btrfsic_block_data_ctx *const first_block_ctx, @@ -1706,8 +1706,9 @@ static void btrfsic_dump_database(struct btrfsic_state *state) * Test whether the disk block contains a tree block (leaf or node) * (note that this test fails for the super block) */ -static int btrfsic_test_for_metadata(struct btrfsic_state *state, - char **datav, unsigned int num_pages) +static noinline_for_stack int btrfsic_test_for_metadata( + struct btrfsic_state *state, + char **datav, unsigned int num_pages) { struct btrfs_fs_info *fs_info = state->fs_info; SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); |