45 lines
1.1 KiB
Diff
45 lines
1.1 KiB
Diff
From f54e1ddea12343991b402abf28be2b94ffbac2c5 Mon Sep 17 00:00:00 2001
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From: Tian Tao <tiantao6@hisilicon.com>
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Date: Tue, 11 Jul 2023 08:42:56 +0800
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Subject: [PATCH] Optimizing __random for single-threaded scenarios
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The __random function does not need to be locked by __libc_lock_lock and
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unlocked by __libc_lock_unlock in a single-threaded scenario, so we can
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remove these locks in a single-threaded scenario to improve performance.
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Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
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---
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stdlib/random.c | 14 +++++++++++---
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1 file changed, 11 insertions(+), 3 deletions(-)
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diff --git a/stdlib/random.c b/stdlib/random.c
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index 62f22fac8d..9035df8d18 100644
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--- a/stdlib/random.c
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+++ b/stdlib/random.c
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@@ -288,11 +288,19 @@ __random (void)
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{
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int32_t retval;
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- __libc_lock_lock (lock);
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+ if (__libc_single_threaded) {
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- (void) __random_r (&unsafe_state, &retval);
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+ (void) __random_r (&unsafe_state, &retval);
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- __libc_lock_unlock (lock);
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+ } else {
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+
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+ __libc_lock_lock (lock);
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+
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+ (void) __random_r (&unsafe_state, &retval);
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+
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+ __libc_lock_unlock (lock);
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+
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+ }
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return retval;
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}
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--
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2.33.0
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