RISC-V and Clang produce rdcycle for __builtin_readcyclecounter.
Since Linux kernel 6.6 this is a privileged instruction not available
to userspace programs.
The use of __builtin_readcyclecounter is excluded from RISCV falling
back to the rdtime/rdtimeh instructions provided in MDEV-33435.
Thanks Alexander Richardson for noting it should be linux only in the
code and noting FreeBSD RISC-V permits rdcycle.
Author: BINSZ on JIRA
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
Change the type of my_hash_get_key to:
1) Return const
2) Change the context parameter to be const void*
Also fix casting in hash adjacent areas.
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
The functions queue_compare, qsort2_cmp, and qsort_cmp2
all had similar interfaces, and were used interchangable
and unsafely cast to one another.
This patch consolidates the functions all into the
qsort_cmp2 interface.
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
The code in best_access_path() uses PREV_BITS(uint, N) to
compute a bitmap of all keyparts: {keypart0, ... keypart{N-1}).
The problem is that PREV_BITS($type, N) macro code can't handle the case
when N=<number of bits in $type).
Also, why use PREV_BITS(uint, ...) for key part map computations when
we could have used PREV_BITS(key_part_map) ?
Fixed both:
- Change PREV_BITS(type, N) to handle any N in [0; n_bits(type)].
- Change PREV_BITS() to use key_part_map when computing key_part_map bitmaps.
The problem was that when using clang + asan, we do not get a correct value
for the thread stack as some local variables are not allocated at the
normal stack.
It looks like that for example clang 18.1.3, when compiling with
-O2 -fsanitize=addressan it puts local variables and things allocated by
alloca() in other areas than on the stack.
The following code shows the issue
Thread 6 "mariadbd" hit Breakpoint 3, do_handle_one_connection
(connect=0x5080000027b8,
put_in_cache=<optimized out>) at sql/sql_connect.cc:1399
THD *thd;
1399 thd->thread_stack= (char*) &thd;
(gdb) p &thd
(THD **) 0x7fffedee7060
(gdb) p $sp
(void *) 0x7fffef4e7bc0
The address of thd is 24M away from the stack pointer
(gdb) info reg
...
rsp 0x7fffef4e7bc0 0x7fffef4e7bc0
...
r13 0x7fffedee7060 140737185214560
r13 is pointing to the address of the thd. Probably some kind of
"local stack" used by the sanitizer
I have verified this with gdb on a recursive call that calls alloca()
in a loop. In this case all objects was stored in a local heap,
not on the stack.
To solve this issue in a portable way, I have added two functions:
my_get_stack_pointer() returns the address of the current stack pointer.
The code is using asm instructions for intel 32/64 bit, powerpc,
arm 32/64 bit and sparc 32/64 bit.
Supported compilers are gcc, clang and MSVC.
For MSVC 64 bit we are using _AddressOfReturnAddress()
As a fallback for other compilers/arch we use the address of a local
variable.
my_get_stack_bounds() that will return the address of the base stack
and stack size using pthread_attr_getstack() or NtCurrentTed() with
fallback to using the address of a local variable and user provided
stack size.
Server changes are:
- Moving setting of thread_stack to THD::store_globals() using
my_get_stack_bounds().
- Removing setting of thd->thread_stack, except in functions that
allocates a lot on the stack before calling store_globals(). When
using estimates for stack start, we reduce stack_size with
MY_STACK_SAFE_MARGIN (8192) to take into account the stack used
before calling store_globals().
I also added a unittest, stack_allocation-t, to verify the new code.
Reviewed-by: Sergei Golubchik <serg@mariadb.org>
Don't allow the referencing key column from NULL TO NOT NULL
when
1) Foreign key constraint type is ON UPDATE SET NULL
2) Foreign key constraint type is ON DELETE SET NULL
3) Foreign key constraint type is UPDATE CASCADE and referenced
column declared as NULL
Don't allow the referenced key column from NOT NULL to NULL
when foreign key constraint type is UPDATE CASCADE
and referencing key columns doesn't allow NULL values
get_foreign_key_info(): InnoDB sends the information about
nullability of the foreign key fields and referenced key fields.
fk_check_column_changes(): Enforce the above rules for COPY
algorithm
innobase_check_foreign_drop_col(): Checks whether the dropped
column exists in existing foreign key relation
innobase_check_foreign_low() : Enforce the above rules for
INPLACE algorithm
dict_foreign_t::check_fk_constraint_valid(): This is used
by CREATE TABLE statement to check nullability for foreign
key relation.
When using the default innodb_log_buffer_size=2m, mariadb-backup --backup
would spend a lot of time re-reading and re-parsing the log. For reads,
it would be beneficial to memory-map the entire ib_logfile0 to the
address space (typically 48 bits or 256 TiB) and read it from there,
both during --backup and --prepare.
We will introduce the Boolean read-only parameter innodb_log_file_mmap
that will be OFF by default on most platforms, to avoid aggressive
read-ahead of the entire ib_logfile0 in when only a tiny portion would be
accessed. On Linux and FreeBSD the default is innodb_log_file_mmap=ON,
because those platforms define a specific mmap(2) option for enabling
such read-ahead and therefore it can be assumed that the default would
be on-demand paging. This parameter will only have impact on the initial
InnoDB startup and recovery. Any writes to the log will use regular I/O,
except when the ib_logfile0 is stored in a specially configured file system
that is backed by persistent memory (Linux "mount -o dax").
We also experimented with allowing writes of the ib_logfile0 via a
memory mapping and decided against it. A fundamental problem would be
unnecessary read-before-write in case of a major page fault, that is,
when a new, not yet cached, virtual memory page in the circular
ib_logfile0 is being written to. There appears to be no way to tell
the operating system that we do not care about the previous contents of
the page, or that the page fault handler should just zero it out.
Many references to HAVE_PMEM have been replaced with references to
HAVE_INNODB_MMAP.
The predicate log_sys.is_pmem() has been replaced with
log_sys.is_mmap() && !log_sys.is_opened().
Memory-mapped regular files differ from MAP_SYNC (PMEM) mappings in the
way that an open file handle to ib_logfile0 will be retained. In both
code paths, log_sys.is_mmap() will hold. Holding a file handle open will
allow log_t::clear_mmap() to disable the interface with fewer operations.
It should be noted that ever since
commit 685d958e38 (MDEV-14425)
most 64-bit Linux platforms on our CI platforms
(s390x a.k.a. IBM System Z being a notable exception) read and write
/dev/shm/*/ib_logfile0 via a memory mapping, pretending that it is
persistent memory (mount -o dax). So, the memory mapping based log
parsing that this change is enabling by default on Linux and FreeBSD
has already been extensively tested on Linux.
::log_mmap(): If a log cannot be opened as PMEM and the desired access
is read-only, try to open a read-only memory mapping.
xtrabackup_copy_mmap_snippet(), xtrabackup_copy_mmap_logfile():
Copy the InnoDB log in mariadb-backup --backup from a memory
mapped file.
Applied SR transaction on the child table was not BF aborted by TOI running
on the parent table for several reasons:
Although SR correctly collected FK-referenced keys to parent, TOI in Galera
disregards common certification index and simply sets itself to depend on
the latest certified write set seqno.
Since this write set was the fragment of SR transaction, TOI was allowed to
run in parallel with SR presuming it would BF abort the latter.
At the same time, DML transactions in the server don't grab MDL locks on
FK-referenced tables, thus parent table wasn't protected by an MDL lock from
SR and it couldn't provoke MDL lock conflict for TOI to BF abort SR transaction.
In InnoDB, DDL transactions grab shared MDL locks on child tables, which is not
enough to trigger MDL conflict in Galera.
InnoDB-level Wsrep patch didn't contain correct conflict resolution logic due to
the fact that it was believed MDL locking should always produce conflicts correctly.
The fix brings conflict resolution rules similar to MDL-level checks to InnoDB,
thus accounting for the problematic case.
Apart from that, wsrep_thd_is_SR() is patched to return true only for executing
SR transactions. It should be safe as any other SR state is either the same as
for any single write set (thus making the two logically equivalent), or it reflects
an SR transaction as being aborting or prepared, which is handled separately in
BF-aborting logic, and for regular execution path it should not matter at all.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>
The strncpy() wrapper that was introduced in
commit 567b681299
is checking whether the output was truncated even in cases
where the caller does not care about it.
Let us introduce a separate function safe_strcpy_truncated() that
indidates whether the output was truncated.
The shared counter template ib_counter_t uses the function
my_timer_cycles() as a source of pseudo-random numbers to pick a shard.
On some platforms, my_timer_cycles() could return the constant value 0.
get_rnd_value(): Remove.
my_pseudo_random(): Implement as an alias of my_timer_cycles() or
a wrapper for pthread_self().
Reviewed by: Vladislav Vaintroub
The problem was that the signal thread was not killed when using
unireg_abort().
The bug was introduced by:
MDEV-30260: Slave crashed:reload_acl_and_cache during shutdown
Other things fixed:
- Don't produce memory leaks with safemalloc if all threads was not
ended properly (not useful)
I checked all stack overflow potential problems found with
gcc -Wstack-usage=16384
and
clang -Wframe-larger-than=16384 -no-inline
Fixes:
Added '#pragma clang diagnostic ignored "-Wframe-larger-than="'
to a lot of function to where stack usage large but resonable.
- Added stack check warnings to BUILD scrips when using clang and debug.
Function changed to use malloc instead allocating things on stack:
- read_bootstrap_query() now allocates line_buffer (20000 bytes) with
malloc() instead of using stack. This has a small performance impact
but this is not releant for bootstrap.
- mroonga grn_select() used 65856 bytes on stack. Changed it to use
malloc().
- Wsrep_schema::replay_transaction() and
Wsrep_schema::recover_sr_transactions().
- Connect zipOpen3()
Not fixed:
- mroonga/vendor/groonga/lib/expr.c grn_proc_call() uses
43712 byte on stack. However this is not easy to fix as the stack
used is caused by a lot of code generated by defines.
- Most changes in mroonga/groonga where only adding of pragmas to disable
stack warnings.
- rocksdb/options/options_helper.cc uses 20288 of stack space.
(no reason to fix except to get rid of the compiler warning)
- Causes using alloca() where the allocation size is resonable.
- An issue in libmariadb (reported to connectors).
Fixed that internal temporary tables are not waiting for freed disk space.
Other things:
- 'kill id' will now kill a query waiting for free disk space instantly.
Before it could take up to 60 seconds for the kill would be noticed.
- Fixed that sorting one index is not using MY_WAIT_IF_FULL for temp files.
- Fixed bug where share->write_flag set MY_WAIT_IF_FULL for temp files.
It is quite hard to do a test case for this. Instead I tested all
combinations interactively.
Some fixes related to commit f838b2d799 and
Rows_log_event::do_apply_event() and Update_rows_log_event::do_exec_row()
for system-versioned tables were provided by Nikita Malyavin.
This was required by test versioning.rpl,trx_id,row.
Add "real ip:<ip_or_localhost>" part to the aborted message
Only for proxy-protocoled connection, so it does not not to cause
confusion to normal users.
Add "real ip:<ip_or_localhost>" part to the aborted message
Only for proxy-protocoled connection, so it does not not to cause
confusion to normal users.
This was caused by wrong allocation of variable on stack.
(Was allocating 4K of data instead of 512 bytes).
No test case as the original MDEV test cases is not usable for mtr.
MDEV-33502 Slowdown when running nested statement with many partitions
caused this error as I failed to take into account bigendian architectures.
This patch also introduces bitmap_import() and bitmap_export() to be used
when one wants to store bitmaps in files/logs in a portable way.
Reviewed-by: Kristian Nielsen <knielsen@knielsen-hq.org>
Warnings are added to net_server.cc when
global_system_variables.log_warnings >= 4.
When the above condition holds then:
- All communication errors from net_serv.cc is also written to the
error log.
- In case of a of not being able to read or write a packet, a more
detailed error is given.
Other things:
- Added detection of slaves that has hangup to Ack_receiver::run()
- vio_close() is now first marking the socket closed before closing it.
The reason for this is to ensure that the connection that gets a read
error can check if the reason was that the socket was closed.
- Add a new state to vio to be able to detect if vio is acive, shutdown or
closed. This is used to detect if socket is closed by another thread.
- Testing of the new warnings is done in rpl_get_lock.test
- Suppress some of the new warnings in mtr to allow one to run some of
the tests with -mysqld=--log-warnings=4. All test in the 'rpl' suite
can now be run with this option.
- Ensure that global.log_warnings are restored at test end in a way
that allows one to use mtr --mysqld=--log-warnings=4.
Reviewed-by: <serg@mariadb.org>,<brandon.nesterenko@mariadb.com>
MDEV-33502 Slowdown when running nested statement with many partitions
This change was triggered to help some MariaDB users with close to
10000 bits in their bitmaps.
- Change underlaying storage to be 64 bit instead of 32bit.
- This reduses number of loops to scan bitmaps.
- This can cause some bitmaps to be 4 byte large.
- Ensure that all not used top-bits are always 0 (simplifes code as
the last 64 bit storage is not a special case anymore).
- Use my_find_first_bit() to find the first set bit which is much faster
than scanning trough things byte by byte and then bit by bit.
Other things:
- Added a bool to remember if my_bitmap_init() did allocate the bitmap
array. my_bitmap_free() will only free arrays it did allocate.
This allowed me to remove setting 'bitmap=0' before calling
my_bitmap_free() for cases where the bitmap's where allocated externally.
- my_bitmap_init() sets bitmap to 0 in case of failure.
- Added 'universal' asserts to most bitmap functions.
- Change all remaining calls to bitmap_init() to my_bitmap_init().
- To finish the change from 2014.
- Changed all usage of uint32 in my_bitmap.h to my_bitmap_map.
- Updated bitmap_copy() to handle bitmaps of different size.
- Removed const from bitmap_exists_intersection() as this caused casts
on all usage.
- Removed not used function bitmap_set_above().
- Renamed create_last_word_mask() to create_last_bit_mask() (to match
name changes in my_bitmap.cc)
- Extended bitmap-t with test for more bitmap functions.
Aria temporary tables account allocated memory as specific to the current
THD. But this fails for slave threads, where the temporary tables need to be
detached from any specific THD.
Introduce a new flag to mark temporary tables in replication as "global",
and use that inside Aria to not account memory allocations as thread
specific for such tables.
Based on original suggestion by Monty.
Reviewed-by: Monty <monty@mariadb.org>
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>