| Age | Commit message (Collapse) | Author |
|---|
|
|
|
This refactor was done using the unifdef tool like this:
for file in $(find erts/ -name *.[ch]); do unifdef -t -f defile -o $file $file; done
where defile contained:
#define ERTS_SMP 1
#define USE_THREADS 1
#define DDLL_SMP 1
#define ERTS_HAVE_SMP_EMU 1
#define SMP 1
#define ERL_BITS_REENTRANT 1
#define ERTS_USE_ASYNC_READY_Q 1
#define FDBLOCK 1
#undef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
#define ERTS_POLL_ASYNC_INTERRUPT_SUPPORT 0
#define ERTS_POLL_USE_WAKEUP_PIPE 1
#define ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE 1
#undef ERTS_HAVE_PLAIN_EMU
#undef ERTS_SIGNAL_STATE
|
|
|
|
Add the possibility to use modules as trace data receivers. The functions
in the module have to be nifs as otherwise complex trace probes will be
very hard to handle (complex means trace probes for ports for example).
This commit changes the way that the ptab->tracer field works from always
being an immediate, to now be NIL if no tracer is present or else be
the tuple {TracerModule, TracerState} where TracerModule is an atom that
is later used to lookup the appropriate tracer callbacks to call and
TracerState is just passed to the tracer callback. The default process and
port tracers have been rewritten to use the new API.
This commit also changes the order which trace messages are delivered to the
potential tracer process. Any enif_send done in a tracer module may be delayed
indefinitely because of lock order issues. If a message is delayed any other
trace message send from that process is also delayed so that order is preserved
for each traced entity. This means that for some trace events (i.e. send/receive)
the events may come in an unintuitive order (receive before send) to the
trace receiver. Timestamps are taken when the trace message is generated so
trace messages from differented processes may arrive with the timestamp
out of order.
Both the erlang:trace and seq_trace:set_system_tracer accept the new tracer
module tracers and also the backwards compatible arguments.
OTP-10267
|
|
|
|
|
|
|
|
|
|
Since: R16B01
Symptom: A spawned process may get the same PID as an existing
process. The new process will "steal" the PID and make the old process
unreachable through the PID.
The problem also applies to port identities but has only been seen
for processes.
Conditions: SMP emulator with at least two scheduler threads. Rapid
spawning and termination of a large number of processes. A small
number of free slots in the process table will also increase the risk
for this bug.
Workaround: Use command line options "+P legacy" and "+Q legacy"
Cause: The race happens if a process terminates and gets stalled while
releasing its process table slot. The stall has to be so long (due to OS
preemptive scheduling most probably) for other schedluer threads to
consume all other free slots for newly spawn processes.
Fix: Write invalid-markers in the free-pid-table and do atomic exhange
operations in retry-loops to make sure each thread gets a unique PID.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
