From ca0425c6ff85262bc15367f5fd9cbc51cde52b20 Mon Sep 17 00:00:00 2001 From: Rickard Green Date: Wed, 2 Oct 2013 10:07:27 +0200 Subject: Execution of system tasks in context of another process A process requesting a system task to be executed in the context of another process will be notified by a message when the task has executed. This message will be on the form: {RequestType, RequestId, Pid, Result}. A process requesting a system task to be executed can set priority on the system task. The requester typically set the same priority on the task as its own process priority, and by this avoiding priority inversion. A request for execution of a system task is made by calling the statically linked in NIF erts_internal:request_system_task(Pid, Prio, Request). This is an undocumented ERTS internal function that should remain so. It should *only* be called from BIF implementations. Currently defined system tasks are: * garbage_collect * check_process_code Further system tasks can and will be implemented in the future. The erlang:garbage_collect/[1,2] and erlang:check_process_code/[2,3] BIFs are now implemented using system tasks. Both the 'garbage_collect' and the 'check_process_code' operations perform or may perform garbage_collections. By doing these via the system task functionality all garbage collect operations in the system will be performed solely in the context of the process being garbage collected. This makes it possible to later implement functionality for disabling garbage collection of a process over context switches. Newly introduced BIFs: * erlang:garbage_collect/2 - The new second argument is an option list. Introduced option: * {async, RequestId} - making it possible for users to issue asynchronous garbage collect requests. * erlang:check_process_code/3 - The new third argument is an option list. Introduced options: * {async, RequestId} - making it possible for users to issue asynchronous check process code requests. * {allow_gc, boolean()} - making it possible to issue requests that aren't allowed to garbage collect (operation will abort if gc should be needed). These options have been introduced as a preparation for parallelization of check_process_code operations when the code_server is about to purge a module. --- erts/emulator/beam/erl_process.h | 74 ++++++++++++++++++++++++++++++++-------- 1 file changed, 60 insertions(+), 14 deletions(-) (limited to 'erts/emulator/beam/erl_process.h') diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h index 8e5467f196..814e3d34df 100644 --- a/erts/emulator/beam/erl_process.h +++ b/erts/emulator/beam/erl_process.h @@ -688,6 +688,9 @@ typedef struct { ErlHeapFragment *bp; } ErtsPendExit; +typedef struct ErtsProcSysTask_ ErtsProcSysTask; +typedef struct ErtsProcSysTaskQs_ ErtsProcSysTaskQs; + #ifdef ERTS_SMP typedef struct ErtsPendingSuspend_ ErtsPendingSuspend; @@ -855,6 +858,7 @@ struct process { Uint64 bin_old_vheap_sz; /* Virtual old heap block size for binaries */ Uint64 bin_old_vheap; /* Virtual old heap size for binaries */ + ErtsProcSysTaskQs *sys_task_qs; erts_smp_atomic32_t state; /* Process state flags (see ERTS_PSFLG_*) */ #ifdef ERTS_SMP @@ -924,24 +928,66 @@ void erts_check_for_holes(Process* p); # error "Need to increase ERTS_PSFLG_PRIO_SHIFT" #endif -#define ERTS_PSFLG_PRIO_SHIFT 2 +#define ERTS_PSFLGS_PRIO_BITS 2 +#define ERTS_PSFLGS_PRIO_MASK \ + ((((erts_aint32_t) 1) << ERTS_PSFLGS_PRIO_BITS) - 1) -#define ERTS_PSFLG_BIT(N) \ - (((erts_aint32_t) 1) << (ERTS_PSFLG_PRIO_SHIFT + (N))) +#define ERTS_PSFLGS_ACT_PRIO_OFFSET (0*ERTS_PSFLGS_PRIO_BITS) +#define ERTS_PSFLGS_USR_PRIO_OFFSET (1*ERTS_PSFLGS_PRIO_BITS) +#define ERTS_PSFLGS_PRQ_PRIO_OFFSET (2*ERTS_PSFLGS_PRIO_BITS) +#define ERTS_PSFLGS_ZERO_BIT_OFFSET (3*ERTS_PSFLGS_PRIO_BITS) -#define ERTS_PSFLG_PRIO_MASK (ERTS_PSFLG_BIT(0) - 1) +#define ERTS_PSFLGS_QMASK_BITS 4 +#define ERTS_PSFLGS_QMASK \ + ((((erts_aint32_t) 1) << ERTS_PSFLGS_QMASK_BITS) - 1) +#define ERTS_PSFLGS_IN_PRQ_MASK_OFFSET \ + ERTS_PSFLGS_ZERO_BIT_OFFSET -#define ERTS_PSFLG_FREE ERTS_PSFLG_BIT(0) -#define ERTS_PSFLG_EXITING ERTS_PSFLG_BIT(1) -#define ERTS_PSFLG_PENDING_EXIT ERTS_PSFLG_BIT(2) -#define ERTS_PSFLG_ACTIVE ERTS_PSFLG_BIT(3) -#define ERTS_PSFLG_IN_RUNQ ERTS_PSFLG_BIT(4) -#define ERTS_PSFLG_RUNNING ERTS_PSFLG_BIT(5) -#define ERTS_PSFLG_SUSPENDED ERTS_PSFLG_BIT(6) -#define ERTS_PSFLG_GC ERTS_PSFLG_BIT(7) -#define ERTS_PSFLG_BOUND ERTS_PSFLG_BIT(8) -#define ERTS_PSFLG_TRAP_EXIT ERTS_PSFLG_BIT(9) +#define ERTS_PSFLG_BIT(N) \ + (((erts_aint32_t) 1) << (ERTS_PSFLGS_ZERO_BIT_OFFSET + (N))) +/* + * ACT_PRIO -> Active prio, i.e., currently active prio. This + * prio may be higher than user prio. + * USR_PRIO -> User prio. i.e., prio the user has set. + * PRQ_PRIO -> Prio queue prio, i.e., prio queue currently + * enqueued in. + */ +#define ERTS_PSFLGS_ACT_PRIO_MASK \ + (ERTS_PSFLGS_PRIO_MASK << ERTS_PSFLGS_ACT_PRIO_OFFSET) +#define ERTS_PSFLGS_USR_PRIO_MASK \ + (ERTS_PSFLGS_PRIO_MASK << ERTS_PSFLGS_USR_PRIO_OFFSET) +#define ERTS_PSFLGS_PRQ_PRIO_MASK \ + (ERTS_PSFLGS_PRIO_MASK << ERTS_PSFLGS_PRQ_PRIO_OFFSET) +#define ERTS_PSFLG_IN_PRQ_MAX ERTS_PSFLG_BIT(0) +#define ERTS_PSFLG_IN_PRQ_HIGH ERTS_PSFLG_BIT(1) +#define ERTS_PSFLG_IN_PRQ_NORMAL ERTS_PSFLG_BIT(2) +#define ERTS_PSFLG_IN_PRQ_LOW ERTS_PSFLG_BIT(3) +#define ERTS_PSFLG_FREE ERTS_PSFLG_BIT(4) +#define ERTS_PSFLG_EXITING ERTS_PSFLG_BIT(5) +#define ERTS_PSFLG_PENDING_EXIT ERTS_PSFLG_BIT(6) +#define ERTS_PSFLG_ACTIVE ERTS_PSFLG_BIT(7) +#define ERTS_PSFLG_IN_RUNQ ERTS_PSFLG_BIT(8) +#define ERTS_PSFLG_RUNNING ERTS_PSFLG_BIT(9) +#define ERTS_PSFLG_SUSPENDED ERTS_PSFLG_BIT(10) +#define ERTS_PSFLG_GC ERTS_PSFLG_BIT(11) +#define ERTS_PSFLG_BOUND ERTS_PSFLG_BIT(12) +#define ERTS_PSFLG_TRAP_EXIT ERTS_PSFLG_BIT(13) +#define ERTS_PSFLG_ACTIVE_SYS ERTS_PSFLG_BIT(14) +#define ERTS_PSFLG_RUNNING_SYS ERTS_PSFLG_BIT(15) +#define ERTS_PSFLG_PROXY ERTS_PSFLG_BIT(16) + +#define ERTS_PSFLGS_IN_PRQ_MASK (ERTS_PSFLG_IN_PRQ_MAX \ + | ERTS_PSFLG_IN_PRQ_HIGH \ + | ERTS_PSFLG_IN_PRQ_NORMAL \ + | ERTS_PSFLG_IN_PRQ_LOW) + +#define ERTS_PSFLGS_GET_ACT_PRIO(PSFLGS) \ + (((PSFLGS) >> ERTS_PSFLGS_ACT_PRIO_OFFSET) & ERTS_PSFLGS_PRIO_MASK) +#define ERTS_PSFLGS_GET_USR_PRIO(PSFLGS) \ + (((PSFLGS) >> ERTS_PSFLGS_USR_PRIO_OFFSET) & ERTS_PSFLGS_PRIO_MASK) +#define ERTS_PSFLGS_GET_PRQ_PRIO(PSFLGS) \ + (((PSFLGS) >> ERTS_PSFLGS_USR_PRIO_OFFSET) & ERTS_PSFLGS_PRIO_MASK) /* The sequential tracing token is a tuple of size 5: * -- cgit v1.2.3 From c6cb0293ba33e1671f8ed670d5add082e5ee674a Mon Sep 17 00:00:00 2001 From: Rickard Green Date: Wed, 30 Oct 2013 17:29:18 +0100 Subject: Functionality for disabling garbage collection Being able to disable garbage collection over context switches vastly simplifies implementation of yielding native code that builds large or complex data structures on the heap. This since the heap can be left in an inconsistent state over the context switch. --- erts/emulator/beam/erl_process.h | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) (limited to 'erts/emulator/beam/erl_process.h') diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h index 814e3d34df..0b8d2976ed 100644 --- a/erts/emulator/beam/erl_process.h +++ b/erts/emulator/beam/erl_process.h @@ -631,8 +631,9 @@ erts_smp_reset_max_len(ErtsRunQueue *rq, ErtsRunQueueInfo *rqi) #define ERTS_PSD_SCHED_ID 2 #define ERTS_PSD_DIST_ENTRY 3 #define ERTS_PSD_CALL_TIME_BP 4 +#define ERTS_PSD_DELAYED_GC_TASK_QS 5 -#define ERTS_PSD_SIZE 5 +#define ERTS_PSD_SIZE 6 typedef struct { void *data[ERTS_PSD_SIZE]; @@ -656,6 +657,9 @@ typedef struct { #define ERTS_PSD_CALL_TIME_BP_GET_LOCKS ERTS_PROC_LOCK_MAIN #define ERTS_PSD_CALL_TIME_BP_SET_LOCKS ERTS_PROC_LOCK_MAIN +#define ERTS_PSD_DELAYED_GC_TASK_QS_GET_LOCKS ERTS_PROC_LOCK_MAIN +#define ERTS_PSD_DELAYED_GC_TASK_QS_SET_LOCKS ERTS_PROC_LOCK_MAIN + typedef struct { ErtsProcLocks get_locks; ErtsProcLocks set_locks; @@ -859,6 +863,7 @@ struct process { Uint64 bin_old_vheap; /* Virtual old heap size for binaries */ ErtsProcSysTaskQs *sys_task_qs; + erts_smp_atomic32_t state; /* Process state flags (see ERTS_PSFLG_*) */ #ifdef ERTS_SMP @@ -976,6 +981,7 @@ void erts_check_for_holes(Process* p); #define ERTS_PSFLG_ACTIVE_SYS ERTS_PSFLG_BIT(14) #define ERTS_PSFLG_RUNNING_SYS ERTS_PSFLG_BIT(15) #define ERTS_PSFLG_PROXY ERTS_PSFLG_BIT(16) +#define ERTS_PSFLG_DELAYED_SYS ERTS_PSFLG_BIT(17) #define ERTS_PSFLGS_IN_PRQ_MASK (ERTS_PSFLG_IN_PRQ_MAX \ | ERTS_PSFLG_IN_PRQ_HIGH \ @@ -1102,6 +1108,7 @@ extern struct erts_system_profile_flags_t erts_system_profile_flags; #define F_HAVE_BLCKD_MSCHED (1 << 8) /* Process has blocked multi-scheduling */ #define F_P2PNR_RESCHED (1 << 9) /* Process has been rescheduled via erts_pid2proc_not_running() */ #define F_FORCE_GC (1 << 10) /* Force gc at process in-scheduling */ +#define F_DISABLE_GC (1 << 11) /* Disable GC */ /* process trace_flags */ #define F_SENSITIVE (1 << 0) @@ -1192,6 +1199,7 @@ void erts_late_init_process(void); void erts_early_init_scheduling(int); void erts_init_scheduling(int, int); +int erts_set_gc_state(Process *c_p, int enable); Eterm erts_sched_wall_time_request(Process *c_p, int set, int enable); Eterm erts_gc_info_request(Process *c_p); Uint64 erts_get_proc_interval(void); @@ -1637,6 +1645,11 @@ erts_psd_set(Process *p, ErtsProcLocks plocks, int ix, void *data) #define ERTS_PROC_SET_CALL_TIME(P, L, PBT) \ ((process_breakpoint_time_t *) erts_psd_set((P), (L), ERTS_PSD_CALL_TIME_BP, (void *) (PBT))) +#define ERTS_PROC_GET_DELAYED_GC_TASK_QS(P) \ + ((ErtsProcSysTaskQs *) erts_psd_get((P), ERTS_PSD_DELAYED_GC_TASK_QS)) +#define ERTS_PROC_SET_DELAYED_GC_TASK_QS(P, L, PBT) \ + ((ErtsProcSysTaskQs *) erts_psd_set((P), (L), ERTS_PSD_DELAYED_GC_TASK_QS, (void *) (PBT))) + ERTS_GLB_INLINE Eterm erts_proc_get_error_handler(Process *p); ERTS_GLB_INLINE Eterm erts_proc_set_error_handler(Process *p, -- cgit v1.2.3