It's a Solaris-only optimization that was used as a workaround for some
infinite loop in pages_map (bug 457189). In the meanwhile, the way
pages_map works has changed in such a way the infinite loop can't happen
anymore.
Specifically, the original problem was that pages_map would try to
allocate something larger than a chunk, then deallocate it, and
reallocate at a hinted aligned address near the address of the now
deallocated mapping, hopefully getting an aligned chunk. But Solaris
would ignore the hint and the chunk would never be aligned, causing the
infinite loop.
What the code does now it over-allocate, find an aligned chunk in there,
and deallocate what ends up not being needed. Which leaves no room for
the original infinite loop.
We thus remove the workaround and put Solaris in par with other Unix
platforms.
--HG--
extra : rebase_source : 9ce4509d9c5ac6123cedabf87c5738672af35d1b
In Gecko code, MOZ_RELEASE_ASSERT means assertions that happen on all
types of builds.
In mozjemalloc, RELEASE_ASSERT means assertions that happen when
MOZ_JEMALLOC_HARD_ASSERTS is set, otherwise normal assertions. Which is
confusing. On the other hand, it's very similar to
MOZ_DIAGNOSTIC_ASSERT, and we may just want to use that instead.
Moreover, with release promotion, the check setting
MOZ_JEMALLOC_HARD_ASSERTS means releases (promoted from beta) would end
up with those asserts while they're not meant to, so
MOZ_DIAGNOSTIC_ASSERT is actually closer to the intent. It however means
we'd lose the beta population running those assertions.
--HG--
extra : rebase_source : 606ab47af8d9ee793b13b806acadb9781c99a078
Support for them was only enabled on debug builds, and required an
opt-in through e.g. MALLOC_OPTIONS to actually enable at runtime.
--HG--
extra : rebase_source : 60c27585c2901a73eb790cec124b880c93da6ef7
While it makes sense for a global system allocator, it's not really
interesting for Firefox to respect that. Plus, newer versions of
jemalloc, which are more likely to be used as a global system allocator
use a different format for the options passed through that file.
--HG--
extra : rebase_source : 0f2283cf5660bc437bd097bf48c2b5989fa08011
Those options, complementing the MALLOC_OPTIONS environment variable,
were always empty since the removal of b2g.
--HG--
extra : rebase_source : 0e34cfce0b537ebb8ed3902bd46180dc205cb0e4
Android NDK defines SYS_mmap2 but it expands to a nonexistent symbol.
mmap2 may not be supported in any case in some AArch64 kernels, so we
should just use mmap.
MozReview-Commit-ID: 5Vjuja5fLIL
The source file is renamed too, because the build system doesn't handle
sources changing suffix very well (at least not without a clobber).
The _GNU_SOURCE define is removed because GCC/Clang set it by default in
C++ mode.
--HG--
rename : memory/mozjemalloc/jemalloc.c => memory/mozjemalloc/mozjemalloc.cpp
extra : rebase_source : f57dbb0a66b25e70fe8c724e9250cc0d8b14f1c1
The hack dates back from the originally imported jemalloc code, which
couldn't assume it's built for Firefox. Now, we can assume that, which
means the code is always built with hidden visibility by default,
removing the need for the explicit hidden visibility.
Correspondingly, when building on Solaris with GCC, the default
visibility should also prevent the inlining, making the noinline
attribute redundant. And the Sun Studio path is useless since the
compiler is not supported anymore.
--HG--
extra : rebase_source : dab0ac68af56b1f9432d312665d4ff3df01fb58a
This avoids many additions of `extern "C"` in C++ code and will avoid
having to do the same to mozjemalloc once built as C++.
--HG--
extra : rebase_source : af55696262f40a9dd16a19c29edcb9bb307d4957
MOZ_JEMALLOC_API makes those symbols exported, but we're going to make
MOZ_JEMALLOC_API include `extern "C"`, which GCC warns about in this
case (can't use extern on a variable that is initialized).
While we could get around this in some way, there is not much use for
those variables being exported altogether: the only reason they are is
to allow an override when linking mozjemalloc into executables, but
doing that in Firefox requires patching the build system or passing some
specific LDFLAGS. People who really need to do that might as well apply
a patch.
They also allow run-time override through LD_PRELOAD, but one might as
well use the MALLOC_OPTIONS environment variable for _malloc_options.
As for _malloc_message, it doesn't seem very useful to override, and
probably noone ever overrode it at runtime.
Note, we may want to remove them in a followup.
--HG--
extra : rebase_source : f2dbe5dbf0bbdb369cd7c6255f624f16b8e37209
Using -Dabort=moz_abort actually makes the build fail in some libstdc++
headers when building as C++.
--HG--
extra : rebase_source : 77828d5c42f231372a8e75f5e3cd6af135d1d5e8
The source file is renamed too, because the build system doesn't handle
sources changing suffix very well (at least not without a clobber).
The _GNU_SOURCE define is removed because GCC/Clang set it by default in
C++ mode.
--HG--
rename : memory/mozjemalloc/jemalloc.c => memory/mozjemalloc/mozjemalloc.cpp
extra : rebase_source : f57dbb0a66b25e70fe8c724e9250cc0d8b14f1c1
The hack dates back from the originally imported jemalloc code, which
couldn't assume it's built for Firefox. Now, we can assume that, which
means the code is always built with hidden visibility by default,
removing the need for the explicit hidden visibility.
Correspondingly, when building on Solaris with GCC, the default
visibility should also prevent the inlining, making the noinline
attribute redundant. And the Sun Studio path is useless since the
compiler is not supported anymore.
--HG--
extra : rebase_source : dab0ac68af56b1f9432d312665d4ff3df01fb58a
This avoids many additions of `extern "C"` in C++ code and will avoid
having to do the same to mozjemalloc once built as C++.
--HG--
extra : rebase_source : af55696262f40a9dd16a19c29edcb9bb307d4957
MOZ_JEMALLOC_API makes those symbols exported, but we're going to make
MOZ_JEMALLOC_API include `extern "C"`, which GCC warns about in this
case (can't use extern on a variable that is initialized).
While we could get around this in some way, there is not much use for
those variables being exported altogether: the only reason they are is
to allow an override when linking mozjemalloc into executables, but
doing that in Firefox requires patching the build system or passing some
specific LDFLAGS. People who really need to do that might as well apply
a patch.
They also allow run-time override through LD_PRELOAD, but one might as
well use the MALLOC_OPTIONS environment variable for _malloc_options.
As for _malloc_message, it doesn't seem very useful to override, and
probably noone ever overrode it at runtime.
Note, we may want to remove them in a followup.
--HG--
extra : rebase_source : f2dbe5dbf0bbdb369cd7c6255f624f16b8e37209
Using -Dabort=moz_abort actually makes the build fail in some libstdc++
headers when building as C++.
--HG--
extra : rebase_source : 77828d5c42f231372a8e75f5e3cd6af135d1d5e8
It's always unset, and Firefox has the logalloc replace-malloc library
for something similar.
--HG--
extra : rebase_source : cfe66c004df0d6e5db749f01feb9af591e3d1569
MOZ_MEMORY is always defined when building mozjemalloc. Due to the
origin of the code, this was all FreeBSD-specific code, and if we want
to add FreeBSD support, we will probably need to add some of it, but I'd
rather avoid keeping the difference between FreeBSD and other posix
systems if we can.
--HG--
extra : rebase_source : 3afe0136e35e25361e9e1802a9738d82b97e99e5
jemalloc_stats, as well as pre/post-fork hooks are using the `arenas`
list along the `narenas` count to iterate over all arenas setup by
mozjemalloc. Up until previous commit, that was used for automatic
multiple arenas support, which is now removed.
But mozjemalloc still supports running with multiple arenas, in the form
of opted-in, per-thread arenas. After bug 1361258, those arenas weren't
tracked, and now that `arenas` only contains the default arena, we can
now fill it with those thread-local arenas.
Keeping the automatic multiple arenas support, which we don't use and
don't really plan to, would have meant using a separate list for them.
--HG--
extra : rebase_source : f4eb55a65df8cdebff84ca709738f906d0c3c6f5
As per explained 2 commits earlier, we remove the support for multiple
arenas. We however keep the `arenas` list and the `narenas` count to
use it them to track the opted-in per-thread arenas.
--HG--
extra : rebase_source : 6e05cddd3dd385a0cd6a22fb028ab311b0c00678
mozjemalloc had an optimization that shortcuts using mutexes when the
program is single-threaded. But with code evolution, the check whether
the program had multiple threads running was meant to be true all the
time.
In order to simplify the code, we just remove those checks and dead code
they were hiding in some cases.
--HG--
extra : rebase_source : 3c7a256bffef50761f6fcd6ec876ebabfcf3fdae
After bug 1361258, mozjemalloc uses a main arena for all allocations,
and specific threads can opt-in to use a different arena for that thread
only. Going forward, this is how we expect to support scaling across
different threads that require lots of concurrent allocations.
To simplify the mozjemalloc code, we'll remove the support for multiple
arenas.
This is the first step towards that, removing the support for arena
balancing. Everything behind the MALLOC_BALANCE macro has never been used
in practice.
--HG--
extra : rebase_source : e7ab669312f1e26a91375d11f5ad488e870bd354
NO_TLS used to be hardcoded on mac because up to 10.6, __thread was not
supported. Until recently, we still supported for 10.6, and it's not the
case anymore, so we could make mac builds use __thread.
Unfortunately, on OSX, __thread circles back calling malloc to allocate
storage on first access, so we have an infinite loop problem here.
Fortunately, pthread_keys don't have this property, so we can use that
instead. It doesn't appear to have significantly more overhead (and TLS
overhead is small anyways compared to the amount of work involved in
allocating memory with mozjemalloc).
At the same time, we uniformize the initialization sequence between
mozjemalloc and mozjemalloc+replace-malloc, such that we have less
occasions for surprises when riding the trains (replace-malloc being
nightly only), ensuring the zone registration happens at the end of
mozjemalloc's initialization.
The function, when passed `true`, creates a new arena with no attachment
in the global list of arenas, and assigns it to the current thread.
When passed `false`, it restores the default arena.
Some details are left out because they don't matter yet, as the sole
initial use of the API is going to invoke the function when stylo rayon
threads start up, which happens exactly once per thread, and at thread
exit time, which happens at shutdown, if ever.
This simplifies things, and leaves those details to followup(s):
- Arenas can't simply be killed when the function is called with `false`
again (or when the thread dies) because they may still contain valid
allocations that could have been passed to other threads. Those arenas
should be kept until they are empty.
- jemalloc_stats doesn't know about them and will under-report memory
usage.
- pre/post fork hooks don't know about them and will not force-unlock
their locks. In practice, until those arenas are used for something
else than the style system, this can't lead to the dead-locks that
these hooks help prevent because nothing should be touching pointers
allocated through them after fork.
Add MOZ_FORMAT_PRINTF to the appropriate spots in DMD and fix up the
one (trivial) error that this pointed out.
MozReview-Commit-ID: LS0UWV5YRoM
--HG--
extra : rebase_source : eb09be39df61a51acd46ed72a1461c495727af79
1. The current asynchronous behavior is pointless, because we still remove the
hashtable entry synchronously, which deletes the value, and it's the value
we're using.
2. Trying to asynchronously delete the value is difficult, and not currently
needed because we can't get a memory-pressure notification while we're using
the value, and hence can't expire it from the expiration tracker.
Note: we can't get this memory-pressure notification because the stage 2 of
mozalloc_handle_oom() to reclaim memory when OOM is not implemented yet.
In order to avoid the possibility of a deadlock if the DMD state lock is
currently acquired when forking a |pthread_atfork| hook is added to wait for
and acquire the lock prior to forking, then release it after forking.
Adapted from
4e2e3dd9cf
and
d9f7b2a430
As per the latter commit, it would seem unlocking, in fork() child
processes, mutexes that were locked in the parent process is not really
well supported on OSX 10.12. The addition of the zone_reinit_lock
function in 10.12 supports this idea.
--HG--
extra : rebase_source : b3b58558cc195d63200078085c7e9b6c9b8d83ff
This picks the same changes as the ones we just did to
memory/build/zone.c, plus a oneliner for sparc64.
--HG--
extra : rebase_source : ca917461472e8188fbfc6e2a971b228b68014e38
Some system libraries are using malloc_default_zone() and then using
some of the malloc_zone_* API. Under normal conditions, those functions
check the malloc_zone_t/malloc_introspection_t struct for the values
that are allowed to be NULL, so that a NULL deref doesn't happen.
As of OSX 10.12, malloc_default_zone() doesn't return the actual default
zone anymore, but returns a fake, wrapper zone. The wrapper zone defines
all the possible functions in the malloc_zone_t/malloc_introspection_t
struct (almost), and calls the function from the registered default zone
(jemalloc in our case) on its own. Without checking whether the pointers
are NULL.
This means that a system library that calls e.g.
malloc_zone_batch_malloc(malloc_default_zone(), ...) ends up trying to
call jemalloc_zone.batch_malloc, which is NULL, and crash follows.
So as of OSX 10.12, the default zone is required to have all the
functions available (really, the same as the wrapper zone), even if they
do nothing.
This is arguably a bug in libsystem_malloc in OSX 10.12, but jemalloc
still needs to work in that case.
[Adapted from
c6943acb3c]
--HG--
extra : rebase_source : 7d7a5b47fa18f56183e99c3655aee003c9be161e
The SDK jemalloc is built against might be not be the latest for various
reasons, but the resulting binary ought to work on newer versions of
OSX.
In order to ensure this, we need the fullest definitions possible, so
copy what we need from the latest version of malloc/malloc.h available
on opensource.apple.com.
[Adapted from
c68bb41793]
--HG--
extra : rebase_source : ab19c478b568ea24095a3be62c39fb81efc1920a
We have been using a different zone allocator between mozjemalloc and
replace-malloc for a long time. Jemalloc 4 uses the same as
replace-malloc, albeit as part of the jemalloc upstream code base.
We've been bitten many times in the past with Apple changes breaking the
zone allocator, and each time we've had to make changes to the three
instances, although two of them are similar and the changes there are
straightforward.
It also turns out that the way the mozjemalloc zone allocator is set up,
when a new version of OSX appears with a new version of the system zone
allocator, Firefox ends up using the system allocator, because the zone
allocator version is not supported.
So, we use the same zone allocator for both replace-malloc and
mozjemalloc, making everything on par with jemalloc 4.
--HG--
extra : rebase_source : 9c0e245b5f82bb71294370d607e690c05cc89fbc
The intent here is to reuse the zone allocator for mozjemalloc, to avoid
all the shortcomings of mozjemalloc using a different one. This change
only moves the replace-malloc zone allocator out of replace-malloc.c, to
make changes for mozjemalloc integration clearer.
--HG--
rename : memory/build/replace_malloc.c => memory/build/zone.c
extra : rebase_source : 8b98efaa4a88862f2967c855b511e92beb9c4031
Somehow, we never called those hooks when replace-malloc is enabled. I'd
expect this to cause random deadlocks when forking, and I'm surprised
this hasn't surfaced. Maybe it actually causes some intermittent oranges
on automation, who knows.
This also brings consistency with what is done for jemalloc 4, and with
the mozjemalloc implementation, too, that we're going to replace with
this one in a subsequent changeset.
--HG--
extra : rebase_source : 059567d17f928098db8367e9081b631ced351110
When built with --enable-debug, jemalloc4 makes headers define functions that
are normally inlined, and that prevents unified sources from working.
--HG--
extra : rebase_source : 9490a0a8312e9be18e639384e3450a9c924e3daf
extra : source : a67867200ec31a040bb6bf8320bde20beb34aa3e