diff options
authorBartosz Golaszewski <>2013-10-16 17:18:05 (GMT)
committerDenys Vlasenko <>2013-10-16 17:18:05 (GMT)
commit28a209466f43c22db42dd02baa136ac7ac25069b (patch)
parent64938011f3ba06a8f425926397172dc361bce851 (diff)
bloat-o-meter: add usage info
Signed-off-by: Bartosz Golaszewski <> Signed-off-by: Denys Vlasenko <>
2 files changed, 16 insertions, 10 deletions
diff --git a/docs/keep_data_small.txt b/docs/keep_data_small.txt
index 21d7326..9fc7996 100644
--- a/docs/keep_data_small.txt
+++ b/docs/keep_data_small.txt
@@ -138,13 +138,6 @@ less readable, use #defines:
#define sector (G.sector)
- Word of caution
-If applet doesn't use much of global data, converting it to use
-one of above methods is not worth the resulting code obfuscation.
-If you have less than ~300 bytes of global data - don't bother.
Finding non-shared duplicated strings
strings busybox | sort | uniq -c | sort -nr
@@ -224,6 +217,14 @@ Result (non-static busybox built against glibc):
Keeping code small
+Use scripts/bloat-o-meter to check whether introduced changes
+didn't generate unnecessary bloat. This script needs unstripped binaries
+to generate a detailed report. To automate this, just use
+"make bloatcheck". It requires busybox_old binary to be present,
+use "make baseline" to generate it from unmodified source, or
+copy busybox_unstripped to busybox_old before modifying sources
+and rebuilding.
Set CONFIG_EXTRA_CFLAGS="-fno-inline-functions-called-once",
produce "make bloatcheck", see the biggest auto-inlined functions.
Now, set CONFIG_EXTRA_CFLAGS back to "", but add NOINLINE
diff --git a/scripts/bloat-o-meter b/scripts/bloat-o-meter
index 6db2a5e..cb861b8 100755
--- a/scripts/bloat-o-meter
+++ b/scripts/bloat-o-meter
@@ -7,11 +7,14 @@
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.
-import sys, os#, re
+import sys, os
def usage():
- sys.stderr.write("usage: %s [-t] file1 file2\n" % sys.argv[0])
- sys.exit(-1)
+ sys.stderr.write("usage: %s [-t] file1 file2 [-- <readelf options>]\n"
+ % sys.argv[0])
+ sys.stderr.write("\t-t\tShow time spent on parsing/processing\n")
+ sys.stderr.write("\t--\tPass additional parameters to readelf\n")
+ sys.exit(1)
f1, f2 = (None, None)
flag_timing, dashes = (False, False)
@@ -31,6 +34,8 @@ for f in sys.argv[1:]:
f1 = f
elif f2 is None:
f2 = f
+ else:
+ usage()
if flag_timing:
import time
if f1 is None or f2 is None: