From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id 69D089000BD for ; Fri, 30 Sep 2011 20:09:11 -0400 (EDT) Received: from d03relay01.boulder.ibm.com (d03relay01.boulder.ibm.com [9.17.195.226]) by e37.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id p9105iD9032145 for ; Fri, 30 Sep 2011 18:05:44 -0600 Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by d03relay01.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p9108v8g151264 for ; Fri, 30 Sep 2011 18:08:59 -0600 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p9108vI5021023 for ; Fri, 30 Sep 2011 18:08:57 -0600 Subject: [RFCv3][PATCH 1/4] replace string_get_size() arrays From: Dave Hansen Date: Fri, 30 Sep 2011 17:08:56 -0700 Message-Id: <20111001000856.DD623081@kernel> Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, rientjes@google.com, James.Bottomley@HansenPartnership.com, hpa@zytor.com, Dave Hansen Instead of explicitly storing the entire string for each possible units, just store the thing that varies: the first character. We have to special-case the 'B' unit (index==0). This shaves about 100 bytes off of my .o file. Signed-off-by: Dave Hansen --- linux-2.6.git-dave/lib/string_helpers.c | 30 ++++++++++++++++++++---------- 1 file changed, 20 insertions(+), 10 deletions(-) diff -puN lib/string_helpers.c~string_get_size-pow2 lib/string_helpers.c --- linux-2.6.git/lib/string_helpers.c~string_get_size-pow2 2011-09-30 16:50:31.628981352 -0700 +++ linux-2.6.git-dave/lib/string_helpers.c 2011-09-30 17:04:02.211607364 -0700 @@ -8,6 +8,23 @@ #include #include +static const char byte_units[] = "_KMGTPEZY"; + +static char *__units_str(enum string_size_units unit, char *buf, int index) +{ + int place = 0; + + /* index=0 is plain 'B' with no other unit */ + if (index) { + buf[place++] = byte_units[index]; + if (unit == STRING_UNITS_2) + buf[place++] = 'i'; + } + buf[place++] = 'B'; + buf[place++] = '\0'; + return buf; +} + /** * string_get_size - get the size in the specified units * @size: The size to be converted @@ -23,26 +40,19 @@ int string_get_size(u64 size, const enum string_size_units units, char *buf, int len) { - const char *units_10[] = { "B", "kB", "MB", "GB", "TB", "PB", - "EB", "ZB", "YB", NULL}; - const char *units_2[] = {"B", "KiB", "MiB", "GiB", "TiB", "PiB", - "EiB", "ZiB", "YiB", NULL }; - const char **units_str[] = { - [STRING_UNITS_10] = units_10, - [STRING_UNITS_2] = units_2, - }; const unsigned int divisor[] = { [STRING_UNITS_10] = 1000, [STRING_UNITS_2] = 1024, }; int i, j; u64 remainder = 0, sf_cap; + char unit_buf[4]; char tmp[8]; tmp[0] = '\0'; i = 0; if (size >= divisor[units]) { - while (size >= divisor[units] && units_str[units][i]) { + while (size >= divisor[units] && (i < strlen(byte_units))) { remainder = do_div(size, divisor[units]); i++; } @@ -61,7 +71,7 @@ int string_get_size(u64 size, const enum } snprintf(buf, len, "%lld%s %s", (unsigned long long)size, - tmp, units_str[units][i]); + tmp, __units_str(units, unit_buf, i)); return 0; } diff -puN include/linux/string_helpers.h~string_get_size-pow2 include/linux/string_helpers.h _ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org