From: Kuan-Wei Chiu <visitorckw@gmail.com>
To: akpm@linux-foundation.org
Cc: jserv@ccns.ncku.edu.tw, linux-kernel@vger.kernel.org,
Kuan-Wei Chiu <visitorckw@gmail.com>
Subject: [PATCH 2/4] lib/sort: Fix outdated comment regarding glibc qsort()
Date: Tue, 28 May 2024 04:30:09 +0800 [thread overview]
Message-ID: <20240527203011.1644280-3-visitorckw@gmail.com> (raw)
In-Reply-To: <20240527203011.1644280-1-visitorckw@gmail.com>
The existing comment in lib/sort refers to glibc qsort() using
quicksort. However, glibc qsort() no longer uses quicksort; it now uses
mergesort and falls back to heapsort if memory allocation for mergesort
fails. This makes the comment outdated and incorrect.
Update the comment to refer to quicksort in general rather than glibc's
implementation to provide accurate information about the comparisons
and trade-offs without implying an outdated implementation.
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
---
lib/sort.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/sort.c b/lib/sort.c
index 651b73205f6d..b918ae15302d 100644
--- a/lib/sort.c
+++ b/lib/sort.c
@@ -5,7 +5,7 @@
* This performs n*log2(n) + 0.37*n + o(n) comparisons on average,
* and 1.5*n*log2(n) + O(n) in the (very contrived) worst case.
*
- * Glibc qsort() manages n*log2(n) - 1.26*n for random inputs (1.63*n
+ * Quicksort manages n*log2(n) - 1.26*n for random inputs (1.63*n
* better) at the expense of stack usage and much larger code to avoid
* quicksort's O(n^2) worst case.
*/
--
2.34.1
next prev parent reply other threads:[~2024-05-27 20:30 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-27 20:30 [PATCH 0/4] lib/sort: Optimizations and cleanups Kuan-Wei Chiu
2024-05-27 20:30 ` [PATCH 1/4] lib/sort: Remove unused pr_fmt macro Kuan-Wei Chiu
2024-05-27 20:30 ` Kuan-Wei Chiu [this message]
2024-05-27 20:30 ` [PATCH 3/4] lib/sort: Optimize heapsort for handling final 2 or 3 elements Kuan-Wei Chiu
2024-05-27 20:30 ` [PATCH 4/4] lib/test_sort: Add a testcase to ensure code coverage Kuan-Wei Chiu
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