glibc/glibc-upstream-2.34-335.patch

69 lines
2.5 KiB
Diff
Raw Normal View History

Import glibc-2.34-48.fc35 from f35 * Thu Oct 13 2022 Arjun Shankar <arjun@redhat.com> - 2.34-48 - Handle non-hostname CNAME aliases during name resolution (#2129005) - Sync with upstream branch release/2.34/master, commit e3976287b22422787f3cc6fc9adda58304b55bd9: - nscd: Drop local address tuple variable [BZ #29607] - x86-64: Require BMI1/BMI2 for AVX2 strrchr and wcsrchr implementations - x86-64: Require BMI2 and LZCNT for AVX2 memrchr implementation - x86-64: Require BMI2 for AVX2 (raw|w)memchr implementations - x86-64: Require BMI2 for AVX2 wcs(n)cmp implementations - x86-64: Require BMI2 for AVX2 strncmp implementation - x86-64: Require BMI2 for AVX2 strcmp implementation - x86-64: Require BMI2 for AVX2 str(n)casecmp implementations - x86: include BMI1 and BMI2 in x86-64-v3 level - nptl: Add backoff mechanism to spinlock loop - sysdeps: Add 'get_fast_jitter' interace in fast-jitter.h - nptl: Effectively skip CAS in spinlock loop - Move assignment out of the CAS condition - Add LLL_MUTEX_READ_LOCK [BZ #28537] - Avoid extra load with CAS in __pthread_mutex_clocklock_common [BZ #28537] - Avoid extra load with CAS in __pthread_mutex_lock_full [BZ #28537] - resolv: Fix building tst-resolv-invalid-cname for earlier C standards - nss_dns: Rewrite _nss_dns_gethostbyname4_r using current interfaces - resolv: Add new tst-resolv-invalid-cname - nss_dns: In gaih_getanswer_slice, skip strange aliases (bug 12154) (#2129005) - nss_dns: Rewrite getanswer_r to match getanswer_ptr (bug 12154, bug 29305) - nss_dns: Remove remnants of IPv6 address mapping - nss_dns: Rewrite _nss_dns_gethostbyaddr2_r and getanswer_ptr - nss_dns: Split getanswer_ptr from getanswer_r - resolv: Add DNS packet parsing helpers geared towards wire format - resolv: Add internal __ns_name_length_uncompressed function - resolv: Add the __ns_samebinaryname function - resolv: Add internal __res_binary_hnok function - resolv: Add tst-resolv-aliases - resolv: Add tst-resolv-byaddr for testing reverse lookup - gconv: Use 64-bit interfaces in gconv_parseconfdir (bug 29583) - elf: Fix hwcaps string size overestimation - nscd: Fix netlink cache invalidation if epoll is used [BZ #29415] - Apply asm redirections in wchar.h before first use - Apply asm redirections in stdio.h before first use [BZ #27087] - elf: Call __libc_early_init for reused namespaces (bug 29528) Resolves: #2129005 Resolves: #2116960
2022-10-14 12:18:43 +00:00
commit 04efdcfac405723c23b25d124817bcfc1697e2d8
Author: Noah Goldstein <goldstein.w.n@gmail.com>
Date: Wed Apr 27 15:13:02 2022 -0500
sysdeps: Add 'get_fast_jitter' interace in fast-jitter.h
'get_fast_jitter' is meant to be used purely for performance
purposes. In all cases it's used it should be acceptable to get no
randomness (see default case). An example use case is in setting
jitter for retries between threads at a lock. There is a
performance benefit to having jitter, but only if the jitter can
be generated very quickly and ultimately there is no serious issue
if no jitter is generated.
The implementation generally uses 'HP_TIMING_NOW' iff it is
inlined (avoid any potential syscall paths).
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit 911c63a51c690dd1a97dfc587097277029baf00f)
diff --git a/sysdeps/generic/fast-jitter.h b/sysdeps/generic/fast-jitter.h
new file mode 100644
index 0000000000000000..4dd53e3475c3dfe6
--- /dev/null
+++ b/sysdeps/generic/fast-jitter.h
@@ -0,0 +1,42 @@
+/* Fallback for fast jitter just return 0.
+ Copyright (C) 2019-2022 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef _FAST_JITTER_H
+# define _FAST_JITTER_H
+
+# include <stdint.h>
+# include <hp-timing.h>
+
+/* Baseline just return 0. We could create jitter using a clock or
+ 'random_bits' but that may imply a syscall and the goal of
+ 'get_fast_jitter' is minimal overhead "randomness" when such
+ randomness helps performance. Adding high overhead the function
+ defeats the purpose. */
+static inline uint32_t
+get_fast_jitter (void)
+{
+# if HP_TIMING_INLINE
+ hp_timing_t jitter;
+ HP_TIMING_NOW (jitter);
+ return (uint32_t) jitter;
+# else
+ return 0;
+# endif
+}
+
+#endif