glibc/glibc-upstream-2.34-334.patch
Arjun Shankar e43852d149 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 14:22:13 +02:00

39 lines
1.3 KiB
Diff

commit 43760d33d78f9ea8c8af942b570112ee801b99df
Author: Jangwoong Kim <6812skiii@gmail.com>
Date: Tue Dec 14 21:30:51 2021 +0900
nptl: Effectively skip CAS in spinlock loop
The commit:
"Add LLL_MUTEX_READ_LOCK [BZ #28537]"
SHA1: d672a98a1af106bd68deb15576710cd61363f7a6
introduced LLL_MUTEX_READ_LOCK, to skip CAS in spinlock loop
if atomic load fails. But, "continue" inside of do-while loop
does not skip the evaluation of escape expression, thus CAS
is not skipped.
Replace do-while with while and skip LLL_MUTEX_TRYLOCK if
LLL_MUTEX_READ_LOCK fails.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit 6b8dbbd03ac88f169b65b5c7d7278576a11d2e44)
diff --git a/nptl/pthread_mutex_lock.c b/nptl/pthread_mutex_lock.c
index 49901ffa0a96d659..bbe754a272b97d91 100644
--- a/nptl/pthread_mutex_lock.c
+++ b/nptl/pthread_mutex_lock.c
@@ -147,10 +147,9 @@ PTHREAD_MUTEX_LOCK (pthread_mutex_t *mutex)
break;
}
atomic_spin_nop ();
- if (LLL_MUTEX_READ_LOCK (mutex) != 0)
- continue;
}
- while (LLL_MUTEX_TRYLOCK (mutex) != 0);
+ while (LLL_MUTEX_READ_LOCK (mutex) != 0
+ || LLL_MUTEX_TRYLOCK (mutex) != 0);
mutex->__data.__spins += (cnt - mutex->__data.__spins) / 8;
}