Revert "Add profiling of already running tasks via SIGINFO/SIGUSR1 (#43179)" (#44184)

This reverts commit a9aad97.

Author: IanButterworth

NEWS.md

@@ -146,17 +146,14 @@ Standard library changes
 * Now uses `textwidth` for formatting `%s` and `%c` widths ([#41085]).
 
 #### Profile
-* CPU profiling now records sample metadata including thread and task. `Profile.print()` has a new `groupby` kwarg that allows
+* Profiling now records sample metadata including thread and task. `Profile.print()` has a new `groupby` kwarg that allows
   grouping by thread, task, or nested thread/task, task/thread, and `threads` and `tasks` kwargs to allow filtering.
   Further, percent utilization is now reported as a total or per-thread, based on whether the thread is idle or not at
   each sample. `Profile.fetch()` by default strips out the new metadata to ensure backwards compatibility with external
   profiling data consumers, but can be included with the `include_meta` kwarg. ([#41742])
 * The new `Profile.Allocs` module allows memory allocations to be profiled. The stack trace, type, and size of each
   allocation is recorded, and a `sample_rate` argument allows a tunable amount of allocations to be skipped,
   reducing performance overhead. ([#42768])
-* A fixed duration cpu profile can now be triggered by the user during running tasks without `Profile` being loaded
-  first and the report will show during execution. On MacOS & FreeBSD press `ctrl-t` or raise a `SIGINFO`.
-  For other platforms raise a `SIGUSR1` i.e. `% kill -USR1 $julia_pid`. Not currently available on windows. ([#43179])
 
 #### Random
 

contrib/generate_precompile.jl

@@ -221,7 +221,6 @@ Profile = get(Base.loaded_modules,
           Base.PkgId(Base.UUID("9abbd945-dff8-562f-b5e8-e1ebf5ef1b79"), "Profile"),
           nothing)
 if Profile !== nothing
-    repl_script *= Profile.precompile_script
     hardcoded_precompile_statements *= """
     precompile(Tuple{typeof(Profile.tree!), Profile.StackFrameTree{UInt64}, Vector{UInt64}, Dict{UInt64, Vector{Base.StackTraces.StackFrame}}, Bool, Symbol, Int, UInt})
     precompile(Tuple{typeof(Profile.tree!), Profile.StackFrameTree{UInt64}, Vector{UInt64}, Dict{UInt64, Vector{Base.StackTraces.StackFrame}}, Bool, Symbol, Int, UnitRange{UInt}})

src/julia_internal.h

@@ -128,10 +128,6 @@ int jl_running_under_rr(int recheck) JL_NOTSAFEPOINT;
 // Returns time in nanosec
 JL_DLLEXPORT uint64_t jl_hrtime(void) JL_NOTSAFEPOINT;
 
-JL_DLLEXPORT void jl_set_peek_cond(uintptr_t);
-JL_DLLEXPORT double jl_get_profile_peek_duration(void);
-JL_DLLEXPORT void jl_set_profile_peek_duration(double);
-
 // number of cycles since power-on
 static inline uint64_t cycleclock(void) JL_NOTSAFEPOINT
 {

src/signal-handling.c

@@ -129,35 +129,6 @@ static size_t jl_safe_read_mem(const volatile char *ptr, char *out, size_t len)
     return i;
 }
 
-static double profile_autostop_time = -1.0;
-static double profile_peek_duration = 1.0; // seconds
-
-double jl_get_profile_peek_duration(void) {
-    return profile_peek_duration;
-}
-void jl_set_profile_peek_duration(double t) {
-    profile_peek_duration = t;
-    return;
-}
-
-uintptr_t profile_show_peek_cond_loc;
-JL_DLLEXPORT void jl_set_peek_cond(uintptr_t cond)
-{
-    profile_show_peek_cond_loc = cond;
-    return;
-}
-
-static void jl_check_profile_autostop(void) {
-    if ((profile_autostop_time != -1.0) && (jl_hrtime() > profile_autostop_time)) {
-        profile_autostop_time = -1.0;
-        jl_profile_stop_timer();
-        jl_safe_printf("\n==============================================================\n");
-        jl_safe_printf("Profile collected. A report will print at the next yield point\n");
-        jl_safe_printf("==============================================================\n\n");
-        uv_async_send((uv_async_t*)profile_show_peek_cond_loc);
-    }
-}
-
 #if defined(_WIN32)
 #include "signals-win.c"
 #else

src/signals-mach.c

@@ -643,7 +643,6 @@ void *mach_profile_listener(void *arg)
         }
         jl_unlock_profile_mach(0, keymgr_locked);
         if (running) {
-            jl_check_profile_autostop();
             // Reset the alarm
             kern_return_t ret = clock_alarm(clk, TIME_RELATIVE, timerprof, profile_port);
             HANDLE_MACH_ERROR("clock_alarm", ret)

src/signals-unix.c

@@ -61,6 +61,7 @@ bt_context_t *jl_to_bt_context(void *sigctx)
 #endif
 }
 
+
 static int thread0_exit_count = 0;
 static void jl_exit_thread0(int exitstate, jl_bt_element_t *bt_data, size_t bt_size);
 
@@ -518,22 +519,17 @@ JL_DLLEXPORT int jl_profile_start_timer(void)
     sigprof.sigev_notify = SIGEV_SIGNAL;
     sigprof.sigev_signo = SIGUSR1;
     sigprof.sigev_value.sival_ptr = &timerprof;
-    // Because SIGUSR1 is multipurpose, set `running` before so that we know that the first SIGUSR1 came from the timer
-    running = 1;
-    if (timer_create(CLOCK_REALTIME, &sigprof, &timerprof) == -1) {
-        running = 0;
+    if (timer_create(CLOCK_REALTIME, &sigprof, &timerprof) == -1)
         return -2;
-    }
 
     // Start the timer
     itsprof.it_interval.tv_sec = 0;
     itsprof.it_interval.tv_nsec = 0;
     itsprof.it_value.tv_sec = nsecprof / GIGA;
     itsprof.it_value.tv_nsec = nsecprof % GIGA;
-    if (timer_settime(timerprof, 0, &itsprof, NULL) == -1) {
-        running = 0;
+    if (timer_settime(timerprof, 0, &itsprof, NULL) == -1)
         return -3;
-    }
+    running = 1;
     return 0;
 }
 
@@ -652,18 +648,6 @@ static void kqueue_signal(int *sigqueue, struct kevent *ev, int sig)
 }
 #endif
 
-void trigger_profile_peek(void)
-{
-    jl_safe_printf("\n======================================================================================\n");
-    jl_safe_printf("Information request received. A stacktrace will print followed by a %.1f second profile\n", profile_peek_duration);
-    jl_safe_printf("======================================================================================\n");
-    bt_size_cur = 0; // clear profile buffer
-    if (jl_profile_start_timer() < 0)
-        jl_safe_printf("ERROR: Could not start profile timer\n");
-    else
-        profile_autostop_time = jl_hrtime() + (profile_peek_duration * 1e9);
-}
-
 static void *signal_listener(void *arg)
 {
     static jl_bt_element_t bt_data[JL_MAX_BT_SIZE + 1];
@@ -769,17 +753,11 @@ static void *signal_listener(void *arg)
 
         int doexit = critical;
 #ifdef SIGINFO
-        if (sig == SIGINFO) {
-            if (running != 1)
-                trigger_profile_peek();
+        if (sig == SIGINFO)
             doexit = 0;
-        }
 #else
-        if (sig == SIGUSR1) {
-            if (running != 1)
-                trigger_profile_peek();
+        if (sig == SIGUSR1)
             doexit = 0;
-        }
 #endif
 
         bt_size = 0;
@@ -857,7 +835,6 @@ static void *signal_listener(void *arg)
         }
 #ifndef HAVE_MACH
         if (profile && running) {
-            jl_check_profile_autostop();
 #if defined(HAVE_TIMER)
             timer_settime(timerprof, 0, &itsprof, NULL);
 #elif defined(HAVE_ITIMER)

src/signals-win.c

@@ -388,7 +388,6 @@ static DWORD WINAPI profile_bt( LPVOID lparam )
                     jl_gc_debug_critical_error();
                     abort();
                 }
-                jl_check_profile_autostop();
             }
         }
     }

stdlib/Profile/docs/src/index.md

@@ -2,79 +2,6 @@
 
 ## CPU Profiling
 
-There are two main approaches to CPU profiling julia code:
-
-## Via `@profile`
-
-Where profiling is enabled for a given call via the `@profile` macro.
-
-```julia-repl
-julia> using Profile
-
-julia> @profile foo()
-
-julia> Profile.print()
-Overhead ╎ [+additional indent] Count File:Line; Function
-=========================================================
-    ╎147  @Base/client.jl:506; _start()
-        ╎ 147  @Base/client.jl:318; exec_options(opts::Base.JLOptions)
-...
-```
-
-## Triggered During Execution
-
-Tasks that are already running can also be profiled for a fixed time period at any user-triggered time.
-
-To trigger the profiling:
-- MacOS & FreeBSD (BSD-based platforms): Use `ctrl-t` or pass a `SIGINFO` signal to the julia process i.e. `% kill -INFO $julia_pid`
-- Linux: Pass a `SIGUSR1` signal to the julia process i.e. `% kill -USR1 $julia_pid`
-- Windows: Not currently supported.
-
-First, a single stack trace at the instant that the signal was thrown is shown, then a 1 second profile is collected,
-followed by the profile report at the next yield point, which may be at task completion for code without yield points
-e.g. tight loops.
-
-```julia-repl
-julia> foo()
-##== the user sends a trigger while foo is running ==##
-load: 2.53  cmd: julia 88903 running 6.16u 0.97s
-
-======================================================================================
-Information request received. A stacktrace will print followed by a 1.0 second profile
-======================================================================================
-
-signal (29): Information request: 29
-__psynch_cvwait at /usr/lib/system/libsystem_kernel.dylib (unknown line)
-_pthread_cond_wait at /usr/lib/system/libsystem_pthread.dylib (unknown line)
-...
-
-======================================================================
-Profile collected. A report will print if the Profile module is loaded
-======================================================================
-
-Overhead ╎ [+additional indent] Count File:Line; Function
-=========================================================
-Thread 1 Task 0x000000011687c010 Total snapshots: 572. Utilization: 100%
-   ╎147 @Base/client.jl:506; _start()
-       ╎ 147 @Base/client.jl:318; exec_options(opts::Base.JLOptions)
-...
-
-Thread 2 Task 0x0000000116960010 Total snapshots: 572. Utilization: 0%
-   ╎572 @Base/task.jl:587; task_done_hook(t::Task)
-      ╎ 572 @Base/task.jl:879; wait()
-...
-```
-
-### Customization
-
-The duration of the profiling can be adjusted via [`Profile.set_peek_duration`](@ref)
-
-The profile report is broken down by thread and task. Pass a no-arg function to `Profile.peek_report[]` to override this.
-i.e. `Profile.peek_report[] = () -> Profile.print()` to remove any grouping. This could also be overridden by an external
-profile data consumer.
-
-## Reference
-
 ```@docs
 Profile.@profile
 ```
@@ -89,8 +16,6 @@ Profile.fetch
 Profile.retrieve
 Profile.callers
 Profile.clear_malloc_data
-Profile.get_peek_duration
-Profile.set_peek_duration
 ```
 
 ## Memory profiling