diff options
author | David Sterba <dsterba@suse.cz> | 2015-02-27 19:37:24 +0100 |
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committer | David Sterba <dsterba@suse.cz> | 2015-06-11 01:10:10 +0200 |
commit | 6d7999d5b747283314c0f3833a3d9515f674a446 (patch) | |
tree | 5af8bb4c6219e6264f7b5ecb680d7b475c9a613f /utils.c | |
parent | 4ceffd0927360c83bec94606112b4e59cb7d2d73 (diff) |
btrfs-progs: use less memory for pretty_size_mode buffers
Anand reports that the static buffers used for pertty size strings cause
a stack overflow on SPARC. Zach proposed to change the printf format to
wrap the number and the suffix into a macro. This would require to
change all callsites of pretty_size* and is not very convienient to
write.
This patch replaces the per-call-site static buffers with a limited
number for slots that would be used on each invokation of pretty_size
and wrap around. The number of array slots shall be 10 for now, in
current codebase there are no more than 2 calls to pretty_size in a
single argument list.
Reported-by: Anand Jain <Anand.Jain@oracle.com>
CC: Zach Brown <zab@zabbo.net>
Signed-off-by: David Sterba <dsterba@suse.cz>
Diffstat (limited to 'utils.c')
-rw-r--r-- | utils.c | 18 |
1 files changed, 18 insertions, 0 deletions
@@ -1479,6 +1479,24 @@ out: return ret; } +/* + * Note: this function uses a static per-thread buffer. Do not call this + * function more than 10 times within one argument list! + */ +const char *pretty_size_mode(u64 size, unsigned mode) +{ + static __thread int ps_index = 0; + static __thread char ps_array[10][32]; + char *ret; + + ret = ps_array[ps_index]; + ps_index++; + ps_index %= 10; + (void)pretty_size_snprintf(size, ret, 32, mode); + + return ret; +} + static const char* unit_suffix_binary[] = { "B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"}; static const char* unit_suffix_decimal[] = |