commit 421d95b3ea introduced a compiler
warning on 32-bit systems about casting a pointer to an integer of a
different size. This commit removes the warning by casting the arguments
to snprintf in the same manner as the original VERIFY3_IMPL macro.
During spa_load the spl->spa_deferred_bpobj maybe be opened and closed
multiple times. It's critical that when the object is closed the
bpo->bpo_object is set to zero to indicate the object is closed.
If it's not during spl_load_retry the spl->spa_deferred_bpobj can
be closes twice resulting in a NULL deref.
This appears to have been fixed upstream the same way.
This reverts commit 411dd65af1.
gcc version 4.1.2 does not like having differing prototypes
for zio_execute, one version in the .c with inline and one
version in the .h without. Thus I'm reverting this change
and we'll see how critical this particular stack reduction is.
This commit preserves the recursive function dbuf_hold_impl() but moves
the local variables and function arguments to the heap to minimize
the stack frame size. Enough space is initially allocated on the
stack for 20 levels of recursion. This technique was based on commit
34229a2f2a which reduced stack usage of
traverse_visitbp().
dbuf_hold_impl() is mutually recursive with dbuf_findbp(),
but the latter function is also called from other functions.
Therefore dbuf_findbp() must contain logic to determine how to call
dbuf_hold_impl(). To this end, dbuf_hold_impl() now takes a
struct dbuf_hold_impl_data pointer as an argument. If that argument
is NULL it calls dbuf_hold_impl() as before, otherwise it calls
__debuf_hold_impl() with a single dbuf_hold_impl_data pointer argument.
As the name implies, dbuf_hold_impl_data stores the arguments and local
variables for dbuf_hold_impl().
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Github issue 22 reported a stack overrun when the zfs module was
loaded, possibly related to the presence of existing zpools created
under zfs-fuse. The stack trace showed 9 levels of recursion between
dsl_scan_visitbp() and dsl_scan_recurse(). To reduce stack overhead in
that code path, this commit moves the 128 byte blkptr_t data strucutre
in dsl_scan_visitbp() to the heap.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Eliminated local variables pointing to members of the zio struct.
Just refer to the struct members directly. This saved about 32 bytes per
call, but this function can be called recurisvely up to 19 levels deep,
so we potentially save up to 608 bytes.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Deep recursive call chains are contributing to segfaults in ztest due to
heavy stack use. Inlining zio_execute() helps reduce the stack depth of
the zio_notify_parent() -> zio_execute() -> zio_wait() recursive cycle.
I am no longer seeing ztest segfaults in this code path with this change.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Deep recursive call chains are contributing to segfaults in ztest due
to heavy stack use. Inlining dbuf_findbp() helps reduce the stack depth
of the dbuf_findbp() -> dbuf_hold_impl() cycle. However, segfaults are
still occurring in this code path, so further reductions are still needed.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Deep recursive call chains are contributing to segfaults in ztest due
to heavy stack use. Inlining zio_notify_parent() helps reduce the
stack depth of the zio_notify_parent() -> zio_execute() -> zio_done()
recursive cycle. I am no longer seeing ztest segfaults in this code
path with this change combined with the zio_done() stack reduction in
the previous commit.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
The spa_load function may call itself recursively through
the spa_load_impl function. This call path of spa_load->
spa_load_impl->spa_load->spa_load_impl takes 640 bytes of
stack. By forcing spa_load_impl to be inlined as part of
spa_load the can be reduced to 448 bytes, for a savings of
192 bytes,
A number of ztest functions create one or more 312B ztest_od_t data
structures. To conserve stack usage, this commit moves all of these data
structures to the heap. However, I am still seeing ztest segfaults due
to heavy stack usage of the dbuf_findbp() -> dbuf_hold_impl() recursion.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Ned Bass
Brian Behlendorf