Small postfix to MDEV-23175 to ensure faster option on FreeBSD
and compatibility to Solaris that isn't high resolution.
ftime is left as a backup in case an implementation doesn't
contain any of these clocks.
FreeBSD
$ ./unittest/mysys/my_rdtsc-t
1..11
# ----- Routine ---------------
# myt.cycles.routine : 5
# myt.nanoseconds.routine : 11
# myt.microseconds.routine : 13
# myt.milliseconds.routine : 11
# myt.ticks.routine : 17
# ----- Frequency -------------
# myt.cycles.frequency : 3610295566
# myt.nanoseconds.frequency : 1000000000
# myt.microseconds.frequency : 1000000
# myt.milliseconds.frequency : 899
# myt.ticks.frequency : 136
# ----- Resolution ------------
# myt.cycles.resolution : 1
# myt.nanoseconds.resolution : 1
# myt.microseconds.resolution : 1
# myt.milliseconds.resolution : 7
# myt.ticks.resolution : 1
# ----- Overhead --------------
# myt.cycles.overhead : 26
# myt.nanoseconds.overhead : 19140
# myt.microseconds.overhead : 19036
# myt.milliseconds.overhead : 578
# myt.ticks.overhead : 21544
ok 1 - my_timer_init() did not crash
ok 2 - The cycle timer is strictly increasing
ok 3 - The cycle timer is implemented
ok 4 - The nanosecond timer is increasing
ok 5 - The nanosecond timer is implemented
ok 6 - The microsecond timer is increasing
ok 7 - The microsecond timer is implemented
ok 8 - The millisecond timer is increasing
ok 9 - The millisecond timer is implemented
ok 10 - The tick timer is increasing
ok 11 - The tick timer is implemented
MariaDB server crashes on ARM (weak memory model architecture) while
concurrently executing l_find to load node->key and add_to_purgatory
to store node->key = NULL. l_find then uses key (which is NULL), to
pass it to a comparison function.
The specific problem is the out-of-order execution that happens on a
weak memory model architecture. Two essential reorderings are possible,
which need to be prevented.
a) As l_find has no barriers in place between the optimistic read of
the key field lf_hash.cc#L117 and the verification of link lf_hash.cc#L124,
the processor can reorder the load to happen after the while-loop.
In that case, a concurrent thread executing add_to_purgatory on the same
node can be scheduled to store NULL at the key field lf_alloc-pin.c#L253
before key is loaded in l_find.
b) A node is marked as deleted by a CAS in l_delete lf_hash.cc#L247 and
taken off the list with an upfollowing CAS lf_hash.cc#L252. Only if both
CAS succeed, the key field is written to by add_to_purgatory. However,
due to a missing barrier, the relaxed store of key lf_alloc-pin.c#L253
can be moved ahead of the two CAS operations, which makes the value of
the local purgatory list stored by add_to_purgatory visible to all threads
operating on the list. As the node is not marked as deleted yet, the
same error occurs in l_find.
This change three accesses to be atomic.
* optimistic read of key in l_find lf_hash.cc#L117
* read of link for verification lf_hash.cc#L124
* write of key in add_to_purgatory lf_alloc-pin.c#L253
Reviewers: Sergei Vojtovich, Sergei Golubchik
Fixes: MDEV-23510 / d30c1331a18d875e553f3fcf544997e4f33fb943
init_mutex_v1_t: Stop lying that the mutex parameter is const.
GCC 11.2.0 assumes that it is and could complain about any mysql_mutex_t
being uninitialized even after mysql_mutex_init() as long as
PLUGIN_PERFSCHEMA is enabled.
init_rwlock_v1_t, init_cond_v1_t: Remove untruthful const qualifiers.
Note: init_socket_v1_t is expecting that the socket fd has already
been created before PSI_SOCKET_CALL(init_socket), and therefore that
parameter really is being treated as a pointer to const.
It seems some overly tolerant compilers (gcc) allow the structure
of IO_CACHE that is defined differently in libmaria to have
members equalivance to the iocache in mysys.
More strict Solaris compilers recognise that rc_pos really
isn't a structure member and won't compile.
volatile != atomic.
volatile has no memory barrier schemantics, its for mmaped IO
so lets allow some optimizer gains and stop pretending it helps
with memory atomicity.
The MDEV lists a SEGV an assumption is made that an address was
partially read. As C packs structs strictly in order and on arm64 the
cache line size is 128 bits. A pointer (link - 64 bits), followed
by a hashnr (uint32 - 32 bits), leaves the following key (uchar *
64 bits), neither naturally aligned to any pointer and worse, split
across a cache line which is the processors view of an atomic
reservation of memory.
lf_dynarray_lvalue is assumed to return a 64 bit aligned address.
As a solution move the 32bit hashnr to the end so we don't get the
*key pointer split across two cache lines.
Tested by: Krunal Bauskar
Reviewer: Marko Mäkelä
Encountered the linker failure on Debug build in 10.4:
[53/585] Linking CXX executable unittest/sql/mf_iocache-t
FAILED: unittest/sql/mf_iocache-t
: && /usr/bin/c++ -pie -fPIC -fstack-protector --param=ssp-buffer-size=4 -fPIC -g -DENABLED_DEBUG_SYNC -ggdb3 -DSAFE_MUTEX -DSAFEMALLOC -DTRASH_FREED_MEMORY -Wall -Wextra -Wno-format-truncation -Wno-init-self -Wno-nonnull-compare -Wno-unused-parameter -Woverloaded-virtual -Wnon-virtual-dtor -Wvla -Wwrite-strings -Werror -Wl,-z,relro,-z,now unittest/sql/CMakeFiles/mf_iocache-t.dir/mf_iocache-t.cc.o unittest/sql/CMakeFiles/mf_iocache-t.dir/__/__/sql/mf_iocache_encr.cc.o -o unittest/sql/mf_iocache-t -lpthread mysys/libmysys.a unittest/mytap/libmytap.a mysys_ssl/libmysys_ssl.a mysys/libmysys.a dbug/libdbug.a mysys/libmysys.a dbug/libdbug.a -lz -lm strings/libstrings.a -lpthread -lssl -lcrypto -ldl && :
/usr/bin/ld: mysys/libmysys.a(my_addr_resolve.c.o):/home/dan/repos/mariadb-server-10.4/mysys/my_addr_resolve.c:173: multiple definition of `info'; unittest/sql/CMakeFiles/mf_iocache-t.dir/mf_iocache-t.cc.o:/home/dan/repos/mariadb-server-10.4/unittest/sql/mf_iocache-t.cc:99: first defined here
We make Dl_info static as in MDEV-21646 moving it out of the function
was the main goal and having it scope limited by static doesn't affect
the function.
This follows up commit
commit 94a520ddbe and
commit 7c5519c12d.
After these changes, the default test suites on a
cmake -DWITH_UBSAN=ON build no longer fail due to passing
null pointers as parameters that are declared to never be null,
but plenty of other runtime errors remain.
According to https://stackoverflow.com/questions/22827510/how-to-avoid-bad-fd-set-buffer-overflow-crash
it seems that using select instead of poll can cause additional memory
allocations. As we are in a crashed state, we must prevent allocating
any memory (if possible). Thus, switch select call to poll.
Also move some bigger datastructures to global space. The code is not
run in a multithreaded context so best we don't use up stack space
if it's not needed.
There are 2 issues here:
Issue #1: memory allocation.
An IO_CACHE that uses encryption uses a larger buffer (it needs space for the encrypted data,
decrypted data, IO_CACHE_CRYPT struct to describe encryption parameters etc).
Issue #2: IO_CACHE::seek_not_done
When IO_CACHE objects are cloned, they still share the file descriptor.
This means, operation on one IO_CACHE may change the file read position
which will confuse other IO_CACHEs using it.
The fix of these issues would be:
Allocate the buffer to also include the extra size needed for encryption.
Perform seek again after one IO_CACHE reads the file.
Passing a null pointer to a nonnull argument is not only undefined
behaviour, but it also grants the compiler the permission to optimize
away further checks whether the pointer is null. GCC -O2 at least
starting with version 8 may do that, potentially causing SIGSEGV.
These problems were caught in a WITH_UBSAN=ON build with the
Bug#7024 test in main.view.
depending on build config the error might be hidded,
in particular liblz4.so and libjemalloc.so make it to disappear,
but with -DWITH_INNODB_LZ4=NO -DWITH_JEMALLOC=NO it reappears.
I run perf top during ./mtr testing and constantly see times()
function there. It's so slow, that it has no sense to run it
in a loop too many times.
This patch speeds up -suite=innodb for me from 218s to 208s.
9s of times() function!
Largely based on MySQL commit
75271e51d6
MySQL Ref:
BUG#24566529: BACKPORT BUG#23575445 TO 5.6
(cut)
Also, the PTR_SANE macro which tries to check if a pointer
is invalid (used when printing pointer values in stack traces)
gave false negatives on OSX/FreeBSD. On these platforms we
now simply check if the pointer is non-null. This also removes
a sbrk() deprecation warning when building on OS X. (It was
before only disabled with building using XCode).
Removed execinfo path of MySQL patch that was already included.
sbrk doesn't exist on FreeBSD aarch64.
Removed HAVE_BSS_START based detection and replaced with __linux__
as it doesn't exist on OSX, Solaris or Windows. __bss_start
exists on mutiple Linux architectures.
Tested on FreeBSD and Linux x86_64. Being in FreeBSD ports for 2
years implies a good testing there on all FreeBSD architectures there
too. MySQL-8.0.21 code is functionally identical to original commit.
queues.c cleanup and refactoring.
Restore old version of _downhead() (from before cd483c5520)
that works well in an average case. Use it for queue_fix().
Move existing specialized version of _downhead() to queue_replace()
where it'll be handling the case it was specifically optimized for
(moving the element to the end of the queue).
And correct it to fix the heap not only down, but also up
(this fixes BUG#30301356).
Add unit tests.
Collateral cosmetic fixes.
sig_return: Solaris/OSX returns different function ptr
Move defination to my_alarm.h as its the only use.
prevents compile warnings (copied from 10.3 branch)
mysys/my_sync.c:136:19: error: 'cur_dir_name' defined but not used [-Werror=unused-const-variable=]
136 | static const char cur_dir_name[]= {FN_CURLIB, 0};
| ^~~~~~~~~~~~
fix compile error (DEPRECATED) leaked from ssl headers.
In file included from /export/home/dan/mariadb-server-10.4/sql/sys_vars.cc:37:
/export/home/dan/mariadb-server-10.4/sql/sys_vars.ic:69: error: "DEPRECATED" redefined [-Werror]
69 | #define DEPRECATED(X) X
|
In file included from /export/home/dan/mariadb-server-10.4/include/violite.h:150,
from /export/home/dan/mariadb-server-10.4/sql/sql_class.h:38,
from /export/home/dan/mariadb-server-10.4/sql/sys_vars.cc:36:
/usr/include/openssl/ssl.h:2356: note: this is the location of the previous definition
2356 | # define DEPRECATED __attribute__((deprecated))
|
Avoid Werror condition on non-Linux:
plugin/server_audit/server_audit.c:2267:7: error: variable 'db_len_off' set but not used [-Werror=unused-but-set-variable]
2267 | int db_len_off;
| ^~~~~~~~~~
plugin/server_audit/server_audit.c:2266:7: error: variable 'db_off' set but not used [-Werror=unused-but-set-variable]
2266 | int db_off;
| ^~~~~~
auth_gssapi fix include path for Solaris
Consistent with the upstream packaged patch:
https://github.com/OpenIndiana/oi-userland/blob/oi/hipster/components/database/mariadb-103/patches/06-gssapi.h.patch
compile warnings on Solaris
[ 91%] Building C object plugin/server_audit/CMakeFiles/server_audit.dir/server_audit.c.o
/plugin/server_audit/server_audit.c: In function 'auditing_v8':
/plugin/server_audit/server_audit.c:2194:20: error: unused variable 'db_len_off' [-Werror=unused-variable]
2194 | static const int db_len_off= 128;
| ^~~~~~~~~~
/plugin/server_audit/server_audit.c:2193:20: error: unused variable 'db_off' [-Werror=unused-variable]
2193 | static const int db_off= 120;
| ^~~~~~
/plugin/server_audit/server_audit.c:2192:20: error: unused variable 'cmd_off' [-Werror=unused-variable]
2192 | static const int cmd_off= 4432;
| ^~~~~~~
At top level:
/plugin/server_audit/server_audit.c:2192:20: error: 'cmd_off' defined but not used [-Werror=unused-const-variable=]
/plugin/server_audit/server_audit.c:2193:20: error: 'db_off' defined but not used [-Werror=unused-const-variable=]
2193 | static const int db_off= 120;
| ^~~~~~
/plugin/server_audit/server_audit.c:2194:20: error: 'db_len_off' defined but not used [-Werror=unused-const-variable=]
2194 | static const int db_len_off= 128;
| ^~~~~~~~~~
cc1: all warnings being treated as errors
tested on:
$ uname -a
SunOS openindiana 5.11 illumos-b97b1727bc i86pc i386 i86pc
read TLS with my_thread_var
write TLS with set_mysys_var()
my_thread_var is no longer __attribute__ ((const)): this attribute
is simply incorrect here. Read gcc manual for more information.
sql/threadpool_generic.cc fails with that attribute.
* `--defaults-file` option is showed only in `--help --verbose` if
applied
* `--default-extra-file` is showing correctly now in `--help --verbose`,
previously it was treated as a directory with appended `my.cnf`
Detecting the cpus based on sysconf of the online CPUs can significantly
over estimate the number of cpus available.
Wheither via numactl, cgroups, taskset, systemd constraints, docker
containers and probably other mechanisms, the number of threads mysqld
can be run on can be quite less.
As such we use the pthread_getaffinity_np function on Linux and FreeBSD
(identical API) to get the number of CPUs.
The number of CPUs is the default for the thread_pool_size and a too
high default will resulting in large memory usage and high context
switching overhead.
Closes PR #922
Restore the detection of default charset in command line utilities.
It worked up to 10.1, but was broken by Connector/C.
Moved code for detection of default charset from sql-common/client.c
to mysys, and make command line utilities to use this code if charset
was not specified on the command line.
