mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Rasmus Villemoes <linux@rasmusvillemoes.dk>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>,
	Rasmus Villemoes <linux@rasmusvillemoes.dk>,
	linux-kernel@vger.kernel.org
Subject: [PATCH 2/3] lib: string_get_size: Use 32 bit arithmetic when possible
Date: Fri, 12 Dec 2014 15:43:47 +0100	[thread overview]
Message-ID: <1418395428-25980-2-git-send-email-linux@rasmusvillemoes.dk> (raw)
In-Reply-To: <1418395428-25980-1-git-send-email-linux@rasmusvillemoes.dk>

The remainder from do_div is always a u32, and after size has been
reduced to be below 1000 (or 1024), it certainly fits in u32. So both
remainder and sf_cap can be made u32s, the format specifiers can be
simplified (%lld wasn't the right thing to use for _unsigned_ long
long anyway), and we can replace a do_div with an ordinary 32/32 bit
division.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
---
 lib/string_helpers.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/lib/string_helpers.c b/lib/string_helpers.c
index 0d25f7aa732c..2b3757f84b3b 100644
--- a/lib/string_helpers.c
+++ b/lib/string_helpers.c
@@ -42,7 +42,7 @@ int string_get_size(u64 size, const enum string_size_units units,
 		[STRING_UNITS_2] = 1024,
 	};
 	int i, j;
-	u64 remainder = 0, sf_cap;
+	u32 remainder = 0, sf_cap;
 	char tmp[8];
 
 	tmp[0] = '\0';
@@ -59,14 +59,13 @@ int string_get_size(u64 size, const enum string_size_units units,
 
 		if (j) {
 			remainder *= 1000;
-			do_div(remainder, divisor[units]);
-			snprintf(tmp, sizeof(tmp), ".%03lld",
-				 (unsigned long long)remainder);
+			remainder /= divisor[units];
+			snprintf(tmp, sizeof(tmp), ".%03u", remainder);
 			tmp[j+1] = '\0';
 		}
 	}
 
-	snprintf(buf, len, "%lld%s %s", (unsigned long long)size,
+	snprintf(buf, len, "%u%s %s", (u32)size,
 		 tmp, units_str[units][i]);
 
 	return 0;
-- 
2.1.3


  reply	other threads:[~2014-12-12 14:44 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-12-12 14:43 [PATCH 1/3] lib: string_get_size: Remove redundant prefixes Rasmus Villemoes
2014-12-12 14:43 ` Rasmus Villemoes [this message]
2014-12-12 14:43 ` [PATCH 3/3] lib: string_get_size: Return void Rasmus Villemoes

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1418395428-25980-2-git-send-email-linux@rasmusvillemoes.dk \
    --to=linux@rasmusvillemoes.dk \
    --cc=James.Bottomley@HansenPartnership.com \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®