/* * \/\/\ * * Copyright (C) 2012-2024 Vito Caputo - * * This program is free software: you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published * by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ /* libvmon integration, warning: this gets a little crazy especially in the rendering. */ #include #include #include #include #include #ifdef USE_XLIB #include #endif #include "charts.h" #include "libvmon/vmon.h" #include "list.h" #include "util.h" #include "vcr.h" #ifdef USE_XLIB #include "composite.h" #include "xwindow.h" #include "vwm.h" #endif #define CHART_ISTHREAD_ARGV "~" /* use this string to mark threads in the argv field */ #define CHART_NOCOMM_ARGV "# missed it!" /* use this string to substitute the command when missing in argv field */ #define CHART_MAX_ARGC 64 /* this is a huge amount */ #define CHART_VMON_PROC_WANTS (VMON_WANT_PROC_STAT | VMON_WANT_PROC_FOLLOW_CHILDREN | VMON_WANT_PROC_FOLLOW_THREADS) #define CHART_VMON_SYS_WANTS (VMON_WANT_SYS_STAT) #define CHART_MAX_COLUMNS 16 /* the global charts state, supplied to vwm_chart_create() which keeps a reference for future use. */ typedef struct _vwm_charts_t { vcr_backend_t *vcr_backend; /* supplied to vwm_charts_create() */ /* libvmon */ struct timeval maybe_sample, last_sample, this_sample; unsigned this_sample_duration; typeof(((vmon_sys_stat_t *)0)->user) last_user_cpu; typeof(((vmon_sys_stat_t *)0)->system) last_system_cpu; unsigned long long last_total, this_total, total_delta; unsigned long long last_idle, last_iowait, idle_delta, iowait_delta; vmon_t vmon; float prev_sampling_interval, sampling_interval; int sampling_paused, contiguous_drops, primed; unsigned defer_maintenance:1; } vwm_charts_t; typedef enum _vwm_column_type_t { VWM_COLUMN_VWM, VWM_COLUMN_ROW, VWM_COLUMN_PROC_USER, VWM_COLUMN_PROC_SYS, VWM_COLUMN_PROC_WALL, VWM_COLUMN_PROC_TREE, VWM_COLUMN_PROC_ARGV, VWM_COLUMN_PROC_PID, VWM_COLUMN_PROC_WCHAN, VWM_COLUMN_PROC_STATE, VWM_COLUMN_CNT } vwm_column_type_t; /* which side to pack the column onto */ typedef enum _vwm_side_t { VWM_SIDE_LEFT, VWM_SIDE_RIGHT, VWM_SIDE_CNT } vwm_side_t; /* how to horizontally justify contents within a given column's area */ typedef enum _vwm_justify_t { VWM_JUSTIFY_LEFT, VWM_JUSTIFY_RIGHT, VWM_JUSTIFY_CENTER, VWM_JUSTIFY_CNT } vwm_justify_t; typedef struct _vwm_column_t { /* TODO: make the columns configurable and add more description/toggled state here */ unsigned enabled:1; vwm_column_type_t type; vwm_side_t side; int width; } vwm_column_t; /* everything needed by the per-window chart's context */ typedef struct _vwm_chart_t { vmon_proc_t *proc; /* vmon process monitor handle */ vcr_t *vcr; int hierarchy_end; /* row where the process hierarchy currently ends */ /* FIXME TODO: this is redundant with the same things in vcr_t now, dedupe them */ int visible_width; /* currently visible width of the chart */ int visible_height; /* currently visible height of the chart */ int snowflakes_cnt; /* count of snowflaked rows (reset to zero to truncate snowflakes display) */ int gen_last_composed; /* the last composed vmon generation */ int redraw_needed; /* if a redraw is required (like when the window is resized...) */ char *name; /* name if provided, included in chart by the \/\/\ */ vwm_column_t columns[CHART_MAX_COLUMNS]; /* columns in the chart TODO, for now just stowing the real/user/sys width here */ vwm_column_t snowflake_columns[CHART_MAX_COLUMNS]; /* columns in the snowflaked rows */ } vwm_chart_t; /* space we need for every process being monitored */ typedef struct _vwm_perproc_ctxt_t { typeof(((vmon_t *)0)->generation) generation; typeof(((vmon_proc_stat_t *)0)->utime) last_utime; typeof(((vmon_proc_stat_t *)0)->stime) last_stime; typeof(((vmon_proc_stat_t *)0)->utime) utime_delta; typeof(((vmon_proc_stat_t *)0)->stime) stime_delta; int row; } vwm_perproc_ctxt_t; static float sampling_intervals[] = { 1, /* ~1Hz */ .1, /* ~10Hz */ .05, /* ~20Hz */ .025, /* ~40Hz */ .01666}; /* ~60Hz */ /* wrapper around snprintf always returning the length of what's in the buf */ static int snpf(char *str, size_t size, const char *format, ...) { va_list ap; int ret; va_start(ap, format); ret = vsnprintf(str, size, format, ap); va_end(ap); return MIN(ret, size - 1); } /* this callback gets invoked at sample time once "per sys" */ static void sample_callback(vmon_t *vmon, void *arg) { vwm_charts_t *charts = arg; vmon_sys_stat_t *sys_stat = vmon->stores[VMON_STORE_SYS_STAT]; charts->this_total = sys_stat->user + sys_stat->nice + sys_stat->system + sys_stat->idle + sys_stat->iowait + sys_stat->irq + sys_stat->softirq + sys_stat->steal + sys_stat->guest; charts->total_delta = charts->this_total - charts->last_total; charts->idle_delta = sys_stat->idle - charts->last_idle; charts->iowait_delta = sys_stat->iowait - charts->last_iowait; } /* these callbacks are invoked by the vmon library when process instances become monitored/unmonitored */ static void vmon_ctor_cb(vmon_t *vmon, vmon_proc_t *proc) { VWM_TRACE("proc->pid=%i", proc->pid); proc->foo = calloc(1, sizeof(vwm_perproc_ctxt_t)); } static void vmon_dtor_cb(vmon_t *vmon, vmon_proc_t *proc) { VWM_TRACE("proc->pid=%i", proc->pid); if (proc->foo) { free(proc->foo); proc->foo = NULL; } } /* initialize charts system */ vwm_charts_t * vwm_charts_create(vcr_backend_t *vbe, unsigned flags) { vwm_charts_t *charts; charts = calloc(1, sizeof(vwm_charts_t)); if (!charts) { VWM_PERROR("unable to allocate vwm_charts_t"); goto _err; } charts->vcr_backend = vbe; if (flags & VWM_CHARTS_FLAG_DEFER_MAINTENANCE) charts->defer_maintenance = 1; charts->prev_sampling_interval = charts->sampling_interval = 0.1f; /* default to 10Hz */ if (!vmon_init(&charts->vmon, VMON_FLAG_2PASS, CHART_VMON_SYS_WANTS, CHART_VMON_PROC_WANTS)) { VWM_ERROR("unable to initialize libvmon"); goto _err_charts; } charts->vmon.proc_ctor_cb = vmon_ctor_cb; charts->vmon.proc_dtor_cb = vmon_dtor_cb; charts->vmon.sample_cb = sample_callback; charts->vmon.sample_cb_arg = charts; gettimeofday(&charts->this_sample, NULL); return charts; _err_charts: free(charts); _err: return NULL; } /* teardown charts system */ void vwm_charts_destroy(vwm_charts_t *charts) { /* TODO: free rest of stuff.. */ free(charts); } /* moves what's below a given row up above it, preserve the lost row's graphs @ hierarchy end */ static void snowflake_row(vwm_charts_t *charts, vwm_chart_t *chart, int row) { VWM_TRACE("pid=%i chart=%p row=%i heirarhcy_end=%i", chart->proc->pid, chart, row, chart->hierarchy_end); /* stash the graph rows */ vcr_stash_row(chart->vcr, VCR_LAYER_GRAPHA, row); vcr_stash_row(chart->vcr, VCR_LAYER_GRAPHB, row); /* shift _all_ the layers up by 1 row */ vcr_shift_below_row_up_one(chart->vcr, row); /* unstash the graph rows @ hierarchy end so we have them in the snowflakes */ vcr_unstash_row(chart->vcr, VCR_LAYER_GRAPHA, chart->hierarchy_end); vcr_unstash_row(chart->vcr, VCR_LAYER_GRAPHB, chart->hierarchy_end); /* clear the others @ hierarchy end, new argv will get stamped over it */ vcr_clear_row(chart->vcr, VCR_LAYER_TEXT, chart->hierarchy_end, -1, -1); vcr_clear_row(chart->vcr, VCR_LAYER_SHADOW, chart->hierarchy_end, -1, -1); } /* XXX TODO libvmon automagic children following races with explicit X client pid monitoring with different outcomes, it should be irrelevant which wins, * currently the only visible difference is the snowflakes gap (hierarchy_end) varies, which is why I haven't bothered to fix it, I barely even notice. */ /* shifts what's below a given row down a row, and clears the row, preparing it for populating */ static void allocate_row(vwm_charts_t *charts, vwm_chart_t *chart, int row) { VWM_TRACE("pid=%i chart=%p row=%i", chart->proc->pid, chart, row); vcr_shift_below_row_down_one(chart->vcr, row); /* FIXME TODO: the vcr layers api needs to just support bitmasks for which layers the operation * applies to. */ vcr_clear_row(chart->vcr, VCR_LAYER_GRAPHA, row, -1, -1); vcr_clear_row(chart->vcr, VCR_LAYER_GRAPHB, row, -1, -1); vcr_clear_row(chart->vcr, VCR_LAYER_TEXT, row, -1, -1); vcr_clear_row(chart->vcr, VCR_LAYER_SHADOW, row, -1, -1); } /* shadow a row from the text layer in the shadow layer */ static void shadow_row(vwm_charts_t *charts, vwm_chart_t *chart, int row) { vcr_shadow_row(chart->vcr, VCR_LAYER_TEXT, row); } /* simple helper to map the vmon per-proc argv array into an XTextItem array, deals with threads vs. processes and the possibility of the comm field not getting read in before the process exited... */ static void proc_argv2strs(const vmon_proc_t *proc, vcr_str_t *strs, int max_strs, int *res_n_strs) { int nr = 0; assert(proc); assert(strs); assert(max_strs > 2); assert(res_n_strs); if (proc->is_thread) { /* stick the thread marker at the start of threads */ strs[0].str = CHART_ISTHREAD_ARGV; strs[0].len = sizeof(CHART_ISTHREAD_ARGV) - 1; nr++; } if (((vmon_proc_stat_t *)proc->stores[VMON_STORE_PROC_STAT])->comm.len) { strs[nr].str = ((vmon_proc_stat_t *)proc->stores[VMON_STORE_PROC_STAT])->comm.array; strs[nr].len = ((vmon_proc_stat_t *)proc->stores[VMON_STORE_PROC_STAT])->comm.len - 1; } else { /* sometimes a process is so ephemeral we don't manage to sample its comm, XXX TODO: we always have a pid, stringify it? */ strs[nr].str = CHART_NOCOMM_ARGV; strs[nr].len = sizeof(CHART_NOCOMM_ARGV) - 1; } nr++; if (!proc->is_thread) { /* suppress the argv for threads */ for (int i = 1; nr < max_strs && i < ((vmon_proc_stat_t *)proc->stores[VMON_STORE_PROC_STAT])->argc; nr++, i++) { strs[nr].str = ((vmon_proc_stat_t *)proc->stores[VMON_STORE_PROC_STAT])->argv[i]; strs[nr].len = strlen(((vmon_proc_stat_t *)proc->stores[VMON_STORE_PROC_STAT])->argv[i]); /* TODO: libvmon should inform us of the length */ } } *res_n_strs = nr; } /* helper for counting number of existing descendants subtrees */ static int count_rows(vmon_proc_t *proc) { int count = 1; /* XXX maybe suppress proc->is_new? */ vmon_proc_t *child; if (!proc->is_thread) { list_for_each_entry(child, &proc->threads, threads) count += count_rows(child); } list_for_each_entry(child, &proc->children, siblings) count += count_rows(child); return count; } /* helper for detecting if any children/threads in the process hierarchy rooted @ proc are new/stale this sample */ static int proc_hierarchy_changed(vmon_proc_t *proc) { vmon_proc_t *child; if (proc->children_changed || proc->threads_changed) return 1; if (!proc->is_thread) { list_for_each_entry(child, &proc->threads, threads) { if (proc_hierarchy_changed(child)) return 1; } } list_for_each_entry(child, &proc->children, siblings) { if (proc_hierarchy_changed(child)) return 1; } return 0; } /* helper for drawing the vertical bars in the graph layers */ static void draw_bars(vwm_charts_t *charts, vwm_chart_t *chart, int row, double mult, double a_fraction, double a_total, double b_fraction, double b_total) { float a_t, b_t; /* compute the bar %ages for this sample */ a_t = a_fraction / a_total * mult; /* TODO: these divides could be turned into multiplies, since the totals are sys-wide uniforms throughout the sample */ b_t = b_fraction / b_total * mult; /* ensure at least 1 pixel when the scaled result is a fraction less than 1, * I want to at least see 1 pixel blips for the slightest cpu utilization */ vcr_draw_bar(chart->vcr, VCR_LAYER_GRAPHA, row, a_t, a_fraction > 0 ? 1 : 0); vcr_draw_bar(chart->vcr, VCR_LAYER_GRAPHB, row, b_t, b_fraction > 0 ? 1 : 0); } /* helper for marking a finish line at the current phase for the specified row */ static void mark_finish(vwm_charts_t *charts, vwm_chart_t *chart, int row) { vcr_mark_finish_line(chart->vcr, VCR_LAYER_GRAPHA, row); vcr_mark_finish_line(chart->vcr, VCR_LAYER_GRAPHB, row); } /* helper for drawing a proc's argv @ specified x offset and row on the chart */ static void print_argv(const vwm_charts_t *charts, const vwm_chart_t *chart, int x, int row, const vmon_proc_t *proc, int *res_width) { vcr_str_t strs[VCR_DRAW_TEXT_N_STRS_MAX]; int n_strs; assert(chart); proc_argv2strs(proc, strs, NELEMS(strs), &n_strs); vcr_draw_text(chart->vcr, VCR_LAYER_TEXT, x, row, strs, n_strs, res_width); } /* determine if a given process has subsequent siblings in the hierarchy */ static inline int proc_has_subsequent_siblings(vmon_t *vmon, vmon_proc_t *proc) { struct list_head *sib, *head = &vmon->processes; if (proc->parent) head = &proc->parent->children; for (sib = proc->siblings.next; sib != head; sib = sib->next) { if (!(list_entry(sib, vmon_proc_t, siblings)->is_stale)) return 1; } return 0; } /* convert chart sampling interval back into an integral hertz value, basically * open-coded ceilf(1.f / charts->sampling_interval) to avoid needing -lm. */ static unsigned interval_as_hz(vwm_charts_t *charts) { return (1.f / charts->sampling_interval + .5f); } /* draw a process' row slice of a process tree */ static void draw_tree_row(vwm_charts_t *charts, vwm_chart_t *chart, int x, int depth, int row, const vmon_proc_t *proc, int *res_width) { /* only if this process isn't the root process @ the window shall we consider all relational drawing conditions */ if (proc != chart->proc) { vmon_proc_t *child, *ancestor, *sibling, *last_sibling = NULL; int bar_x = 0, bar_y = (row + 1) * VCR_ROW_HEIGHT; int sub; /* XXX: everything done in this code block only dirties _this_ process' row in the rendered chart output */ /* walk up the ancestors until reaching chart->proc, any ancestors we encounter which have more siblings we draw a vertical bar for */ /* this draws the |'s in something like: | | | | comm */ for (sub = 1, ancestor = proc->parent; ancestor && ancestor != chart->proc; ancestor = ancestor->parent, sub++) { bar_x = ((depth - 1) - sub) * (VCR_ROW_HEIGHT / 2) + 4; assert(depth > 0); /* determine if the ancestor has remaining siblings which are not stale, if so, draw a connecting bar at its depth */ if (proc_has_subsequent_siblings(&charts->vmon, ancestor)) vcr_draw_ortho_line(chart->vcr, VCR_LAYER_TEXT, x + bar_x, bar_y - VCR_ROW_HEIGHT, /* dst x1, y1 */ x + bar_x, bar_y); /* dst x2, y2 (vertical line) */ } /* determine if _any_ of our siblings have children requiring us to draw a tee immediately before our comm string. * The only sibling which doesn't cause this to happen is the last one in the children list, if it has children it has no impact on its remaining * siblings, as there are none. * * This draws the + in something like: | | | | +comm */ /* find the last sibling (this has to be done due to the potential for stale siblings at the tail, and we'd rather not repeatedly check for it) */ list_for_each_entry(sibling, &proc->parent->children, siblings) { if (!sibling->is_stale) last_sibling = sibling; } /* now look for siblings with non-stale children to determine if a tee is needed, ignoring the last sibling */ list_for_each_entry(sibling, &proc->parent->children, siblings) { int needs_tee = 0; /* skip stale siblings, they aren't interesting as they're invisible, and the last sibling has no bearing on wether we tee or not. */ if (sibling->is_stale || sibling == last_sibling) continue; /* if any of the other siblings have children which are not stale, put a tee in front of our name, but ignore stale children */ list_for_each_entry(child, &sibling->children, siblings) { if (!child->is_stale) { needs_tee = 1; break; } } /* if we still don't think we need a tee, check if there are threads */ if (!needs_tee) { list_for_each_entry(child, &sibling->threads, threads) { if (!child->is_stale) { needs_tee = 1; break; } } } /* found a tee is necessary, all that's left is to determine if the tee is a corner and draw it accordingly, stopping the search. */ if (needs_tee) { bar_x = (depth - 1) * (VCR_ROW_HEIGHT / 2) + 4; /* if we're the last sibling, corner the tee by shortening the vbar */ if (proc == last_sibling) { vcr_draw_ortho_line(chart->vcr, VCR_LAYER_TEXT, x + bar_x, bar_y - VCR_ROW_HEIGHT, /* dst x1, y1 */ x + bar_x, bar_y - 4); /* dst x2, y2 (vertical bar) */ } else { vcr_draw_ortho_line(chart->vcr, VCR_LAYER_TEXT, x + bar_x, bar_y - VCR_ROW_HEIGHT, /* dst x1, y1 */ x + bar_x, bar_y); /* dst x2, y2 (vertical bar) */ } vcr_draw_ortho_line(chart->vcr, VCR_LAYER_TEXT, x + bar_x, bar_y - 4, /* dst x1, y1 */ x + bar_x + 2, bar_y - 4); /* dst x2, y2 (horizontal bar) */ /* terminate the outer sibling loop upon drawing the tee... */ break; } } if (res_width) *res_width = depth * (VCR_ROW_HEIGHT / 2); } } /* draw a proc row according to the columns configured in columns, * row==0 is treated specially as the heading row */ static void draw_columns(vwm_charts_t *charts, vwm_chart_t *chart, vwm_column_t *columns, int depth, int row, const vmon_proc_t *proc) { vmon_sys_stat_t *sys_stat = charts->vmon.stores[VMON_STORE_SYS_STAT]; vmon_proc_stat_t *proc_stat = proc->stores[VMON_STORE_PROC_STAT]; vwm_perproc_ctxt_t *proc_ctxt = proc->foo; char str[256]; for (int i = 0, left = 0, right = 0; i < CHART_MAX_COLUMNS; i++) { vwm_column_t *c = &columns[i]; vwm_justify_t str_justify = VWM_JUSTIFY_CENTER; int str_len = 0, uniform = 1, advance = 1; if (!c->enabled) continue; /* XXX FIXME: i don't constrain columns using a clip mask or restrained drawing, so they can scribble * on neighboring cells, this is especially problematic with long ARGVs like when compiling. * As a kludge to work around this for now, clear the column's area immediately before drawing it, * just in case something else scribbled into it. This doesn't prevent subsequent scribbles, and if * a column's width became too large, the clearing itself can be destructive. This works fine for * the currently configured columns, but long-term this will have to get fixed properly. */ if (c->side == VWM_SIDE_LEFT) vcr_clear_row(chart->vcr, VCR_LAYER_TEXT, row, left, c->width + VCR_ROW_HEIGHT / 2); else vcr_clear_row(chart->vcr, VCR_LAYER_TEXT, row, chart->visible_width - (c->width + VCR_ROW_HEIGHT / 2 + right), c->width + VCR_ROW_HEIGHT / 2); switch (c->type) { case VWM_COLUMN_VWM: if (!row) /* "\/\/\ # name @ XXHz" is only relevant to the heading */ str_len = snpf(str, sizeof(str), "\\/\\/\\%s%s @ %2uHz ", chart->name ? " # " : "", chart->name ? chart->name : "", interval_as_hz(charts)); uniform = 0; /* XXX this suppresses the c->width assignment so the column can be absent outside the heading */ str_justify = VWM_JUSTIFY_RIGHT; break; case VWM_COLUMN_ROW: /* row in the chart */ if (!row) str_len = snpf(str, sizeof(str), "Row"); else str_len = snpf(str, sizeof(str), "%i", row); str_justify = VWM_JUSTIFY_LEFT; /* this is kind of hacky, but libvmon doesn't monitor our row, it's implicitly "sampled" when we draw */ proc_ctxt->row = row; break; case VWM_COLUMN_PROC_USER: /* User CPU time */ if (!row) str_len = snpf(str, sizeof(str), "User"); else str_len = snpf(str, sizeof(str), "%.2fs", (float)proc_stat->utime / (float)charts->vmon.ticks_per_sec); str_justify = VWM_JUSTIFY_RIGHT; break; case VWM_COLUMN_PROC_SYS: /* Sys CPU time */ if (!row) str_len = snpf(str, sizeof(str), "Sys"); else str_len = snpf(str, sizeof(str), "%.2fs", (float)proc_stat->stime / (float)charts->vmon.ticks_per_sec); str_justify = VWM_JUSTIFY_RIGHT; break; case VWM_COLUMN_PROC_WALL: /* User Sys Wall times */ if (!row) str_len = snpf(str, sizeof(str), "Wall"); else if (!proc_stat->start || proc_stat->start > sys_stat->boottime) str_len = snpf(str, sizeof(str), "??s"); else str_len = snpf(str, sizeof(str), "%.2fs", (float)(sys_stat->boottime - proc_stat->start) / (float)charts->vmon.ticks_per_sec); str_justify = VWM_JUSTIFY_RIGHT; break; case VWM_COLUMN_PROC_TREE: { /* print a row of the process hierarchy tree */ int width = 0; advance = 0; /* tree column manages its own advance; c->width is meaningless */ if (!row) /* tree markup needs no heading */ break; assert(c->side == VWM_SIDE_LEFT); /* XXX: technically SIDE_RIGHT could work, but doesn't currently */ draw_tree_row(charts, chart, left, depth, row, proc, &width); left += width; break; } case VWM_COLUMN_PROC_ARGV: { /* print the process' argv */ if (!row) { str_len = snpf(str, sizeof(str), "ArgV/~ThreadName"); str_justify = VWM_JUSTIFY_LEFT; } else { int width; print_argv(charts, chart, left /* FIXME: consider c->side */, row, proc, &width); if (width > c->width) { c->width = width; chart->redraw_needed++; } } break; } case VWM_COLUMN_PROC_PID: /* print the process' PID */ if (!row) str_len = snpf(str, sizeof(str), "PID"); else str_len = snpf(str, sizeof(str), "%5i", proc->pid); str_justify = VWM_JUSTIFY_RIGHT; break; case VWM_COLUMN_PROC_WCHAN: /* print the process' wchan */ if (!row) str_len = snpf(str, sizeof(str), "WChan"); else { /* don't show wchan for processes with threads, since their main thread will show it. */ if (!proc->is_thread && !list_empty(&proc->threads)) break; str_len = snpf(str, sizeof(str), "%.*s", proc_stat->wchan.len, proc_stat->wchan.len == 1 && proc_stat->wchan.array[0] == '0' ? "-" : proc_stat->wchan.array); } str_justify = VWM_JUSTIFY_RIGHT; break; case VWM_COLUMN_PROC_STATE: /* print the process' state */ if (!row) str_len = snpf(str, sizeof(str), "State"); else { /* don't show process state for processes with threads, since their main thread will show it. */ if (!proc->is_thread && !list_empty(&proc->threads)) break; str_len = snpf(str, sizeof(str), "%c", proc_stat->state); } str_justify = VWM_JUSTIFY_CENTER; break; default: assert(0); } /* for plain string draws, str_len is left non-zero and they all get handled equally here */ if (str_len) { const vcr_str_t strs[1] = { (vcr_str_t){.str = str, .len = str_len} }; int str_width, xpos; /* get the width first, so we can place the text, note the -1 to suppress drawings */ vcr_draw_text(chart->vcr, VCR_LAYER_TEXT, -1 /* x */, -1 /* row */, strs, 1, &str_width); if (uniform && str_width > c->width) { c->width = str_width; chart->redraw_needed++; } /* get xpos to the left edge of the column WRT c->width and c->side */ switch (c->side) { case VWM_SIDE_LEFT: xpos = left; break; case VWM_SIDE_RIGHT: xpos = chart->visible_width - (right + c->width); break; default: assert(0); } /* adjust xpos according to str_justify and c->width */ switch (str_justify) { case VWM_JUSTIFY_LEFT: /* xpos already @ left */ break; case VWM_JUSTIFY_RIGHT: xpos += c->width - str_width; break; case VWM_JUSTIFY_CENTER: xpos += (c->width - str_width) / 2; break; default: assert(0); } vcr_draw_text(chart->vcr, VCR_LAYER_TEXT, xpos, row, strs, 1, NULL); } if (advance) { left += (c->side == VWM_SIDE_LEFT) * (c->width + VCR_ROW_HEIGHT / 2); right += (c->side == VWM_SIDE_RIGHT) * (c->width + VCR_ROW_HEIGHT / 2); } } } /* return if any of the enabled columns in columns has changed its contents */ static int columns_changed(const vwm_charts_t *charts, const vwm_chart_t *chart, vwm_column_t *columns, int row, const vmon_proc_t *proc) { vmon_sys_stat_t *sys_stat = charts->vmon.stores[VMON_STORE_SYS_STAT]; vmon_proc_stat_t *proc_stat = proc->stores[VMON_STORE_PROC_STAT]; vwm_perproc_ctxt_t *proc_ctxt = proc->foo; for (int i = 0; i < CHART_MAX_COLUMNS; i++) { const vwm_column_t *c = &columns[i]; if (!c->enabled) continue; switch (c->type) { case VWM_COLUMN_VWM: /* XXX: meh, maybe we should detect Hz changes here? */ break; case VWM_COLUMN_ROW: return (row != proc_ctxt->row); case VWM_COLUMN_PROC_USER: if (BITTEST(proc_stat->changed, VMON_PROC_STAT_UTIME)) return 1; break; case VWM_COLUMN_PROC_SYS: if (BITTEST(proc_stat->changed, VMON_PROC_STAT_STIME)) return 1; break; case VWM_COLUMN_PROC_WALL: if (BITTEST(proc_stat->changed, VMON_PROC_STAT_START) || BITTEST(sys_stat->changed, VMON_SYS_STAT_BOOTTIME)) return 1; break; case VWM_COLUMN_PROC_TREE: break; case VWM_COLUMN_PROC_ARGV: if (BITTEST(proc_stat->changed, VMON_PROC_STAT_ARGV)) return 1; break; case VWM_COLUMN_PROC_PID: if (BITTEST(proc_stat->changed, VMON_PROC_STAT_PID)) return 1; break; case VWM_COLUMN_PROC_WCHAN: if (BITTEST(proc_stat->changed, VMON_PROC_STAT_WCHAN)) return 1; break; case VWM_COLUMN_PROC_STATE: if (BITTEST(proc_stat->changed, VMON_PROC_STAT_STATE)) return 1; break; default: assert(0); } } return 0; } /* draws proc in a row of the process hierarchy */ static void draw_overlay_row(vwm_charts_t *charts, vwm_chart_t *chart, vmon_proc_t *proc, int depth, int row, int deferred_pass) { /* if we're in defer_maintenance mode, don't do any of this until the deferred pass */ if (charts->defer_maintenance && !deferred_pass) return; /* skip if obviously unnecessary (this can be further improved, but this makes a big difference as-is) */ if (!deferred_pass && !chart->redraw_needed && !columns_changed(charts, chart, chart->columns, row, proc)) return; if (!proc->is_new) /* XXX for now always clear the row, this should be capable of being optimized in the future (if the datums driving the text haven't changed...) */ vcr_clear_row(chart->vcr, VCR_LAYER_TEXT, row, -1, -1); draw_columns(charts, chart, chart->columns, depth, row, proc); shadow_row(charts, chart, row); } /* recursive draw function for "rest" of chart: the per-process rows (hierarchy, argv, state, wchan, pid...) */ static void draw_chart_rest(vwm_charts_t *charts, vwm_chart_t *chart, vmon_proc_t *proc, int *depth, int *row, int deferred_pass, unsigned sample_duration_idx) { vmon_proc_stat_t *proc_stat = proc->stores[VMON_STORE_PROC_STAT]; vwm_perproc_ctxt_t *proc_ctxt = proc->foo; vmon_proc_t *child; double utime_delta, stime_delta; /* Some parts of this we must do on every sample to maintain coherence in the graphs, since they're incrementally kept * in sync with the process hierarchy, allocating and shifting the rows as processes are created and destroyed. Everything * else we should be able to skip doing unless chart.redraw_needed or their contents changed. */ /* if this is a deferred pass, we need to simply skip stale nodes, since they've already * been snowflaked incrementally in the !deferred_pass branch below. * Handling them in the deferred pass as well would just scribble over the snowflakes with * stale stuff erroneously lingering in the live tree rows. */ if (deferred_pass && proc->is_stale) return; if (!deferred_pass) { /* These incremental/structural aspects can't be repeated in the final defer_maintenance pass since it's * a repeated pass within the same sample - we can't realize these effects twice. */ if (sample_duration_idx == 0) { /* some things need to only be done once per sample duration, some at the start, some at the end */ if (proc->is_stale) { /* we "realize" stale processes only in the first draw within a sample duration */ /* what to do when a process (subtree) has gone away */ static int in_stale = 0; int in_stale_entrypoint = 0; /* I snowflake the stale processes from the leaves up for a more intuitive snowflake order... * (I expect the command at the root of the subtree to appear at the top of the snowflakes...) */ /* This does require that I do a separate forward recursion to determine the number of rows * so I can correctly snowflake in reverse */ if (!in_stale) { VWM_TRACE("entered stale at chart=%p depth=%i row=%i", chart, *depth, *row); in_stale_entrypoint = in_stale = 1; (*row) += count_rows(proc) - 1; } (*depth)++; list_for_each_entry_prev(child, &proc->children, siblings) { draw_chart_rest(charts, chart, child, depth, row, deferred_pass, sample_duration_idx); (*row)--; } if (!proc->is_thread) { list_for_each_entry_prev(child, &proc->threads, threads) { draw_chart_rest(charts, chart, child, depth, row, deferred_pass, sample_duration_idx); (*row)--; } } (*depth)--; VWM_TRACE("%i (%.*s) is stale @ depth %i row %i is_thread=%i", proc->pid, ((vmon_proc_stat_t *)proc->stores[VMON_STORE_PROC_STAT])->comm.len - 1, ((vmon_proc_stat_t *)proc->stores[VMON_STORE_PROC_STAT])->comm.array, (*depth), (*row), proc->is_thread); mark_finish(charts, chart, (*row)); /* extract the row from the various layers */ snowflake_row(charts, chart, (*row)); chart->snowflakes_cnt++; /* stamp the name (and whatever else we include) into chart.text_picture */ // print_argv(charts, chart, 5, chart->hierarchy_end, proc, NULL); draw_columns(charts, chart, chart->snowflake_columns, 0, chart->hierarchy_end, proc); shadow_row(charts, chart, chart->hierarchy_end); chart->hierarchy_end--; if (in_stale_entrypoint) { VWM_TRACE("exited stale at chart=%p depth=%i row=%i", chart, *depth, *row); in_stale = 0; } return; } /* use the generation number to avoid recomputing this stuff for callbacks recurring on the same process in the same sample */ if (proc_ctxt->generation != charts->vmon.generation) { proc_ctxt->stime_delta = proc_stat->stime - proc_ctxt->last_stime; proc_ctxt->utime_delta = proc_stat->utime - proc_ctxt->last_utime; proc_ctxt->last_utime = proc_stat->utime; proc_ctxt->last_stime = proc_stat->stime; proc_ctxt->generation = charts->vmon.generation; } } if (proc->is_stale) return; /* is_stale is already handled on the first sample_diration_idx */ /* we "realize" new processes on the last draw within a duration. * FIXME TODO: this could be placed more accurately in time by referencing the process's * PROC_STAT_START time and allocating the row at that point within a duration. * but for now it's still an improvement over losing time to simply place it at the end of * the duration. We don't have two samples to compute cpu utilizations for it anyways, so * even if we were to place it accurately on the timeline, there wouldn't be data to put * in the intervening space between the start line and the end anyways, which would be less * accurate/potentially misleading - basically the start line would have to be repeated to * fill in the space where we have no data so as to still indicate "hey, the process started * back here, but this filled white region is where we couldn't collect anything about it * since its start point. This raises an interesting issue in general surrounding start lines * in general; many processes tend to already exist when vmon starts up, and we draw the start * lines when we begin monitoring a given process... and that is misleading if the process was * preexisting. In such caes, when the start time is way in the past, we should either suppress * the start line, or be willing to place it out of phase - if the graph covers that moment. If * we were to place it out of phase, we'd have another situation where we can't leave the space * between then and the current sample empty, it would have to all be filled with start line. */ if (proc->is_new) { if (sample_duration_idx != (charts->this_sample_duration - 1)) return; /* suppress doing anything aboout new processes until the last draw within the duration */ /* what to do when a process has been introduced */ VWM_TRACE("%i is new", proc->pid); allocate_row(charts, chart, (*row)); chart->hierarchy_end++; /* we need a minimum of two samples before we can compute a delta to plot, * so we suppress that and instead mark the start of monitoring with an impossible 100% of both graph contexts, a starting line. */ stime_delta = utime_delta = charts->total_delta; } else { stime_delta = proc_ctxt->stime_delta; utime_delta = proc_ctxt->utime_delta; } draw_bars(charts, chart, *row, (proc->is_thread || !proc->is_threaded) ? charts->vmon.num_cpus : 1.0, stime_delta, charts->total_delta, utime_delta, charts->total_delta); } /* only try draw the overlay on the last draw within a duration */ if (sample_duration_idx == (charts->this_sample_duration - 1)) draw_overlay_row(charts, chart, proc, *depth, *row, deferred_pass); (*row)++; /* recur any threads first, then any children processes */ (*depth)++; if (!proc->is_thread) { /* XXX: the threads member serves as the list head only when not a thread */ list_for_each_entry(child, &proc->threads, threads) { draw_chart_rest(charts, chart, child, depth, row, deferred_pass, sample_duration_idx); } } list_for_each_entry(child, &proc->children, siblings) { draw_chart_rest(charts, chart, child, depth, row, deferred_pass, sample_duration_idx); } (*depth)--; } /* recursive draw function entrypoint, draws the IOWait/Idle/HZ row, then enters draw_chart_rest() */ static void draw_chart(vwm_charts_t *charts, vwm_chart_t *chart, vmon_proc_t *proc, int *depth, int *row, int deferred_pass, unsigned sample_duration_idx) { int prev_redraw_needed = chart->redraw_needed; /* IOWait and Idle % @ row 0 */ draw_bars(charts, chart, 0, 1.0, charts->iowait_delta, charts->total_delta, charts->idle_delta, charts->total_delta); /* only draw the \/\/\ and HZ if necessary */ if (sample_duration_idx == (charts->this_sample_duration - 1)) { if (deferred_pass || (!charts->defer_maintenance && (chart->redraw_needed || charts->prev_sampling_interval != charts->sampling_interval))) { vcr_clear_row(chart->vcr, VCR_LAYER_TEXT, 0, -1, -1); draw_columns(charts, chart, chart->columns, 0, 0, proc); shadow_row(charts, chart, 0); } if (!prev_redraw_needed) chart->redraw_needed = proc_hierarchy_changed(proc); } (*row)++; draw_chart_rest(charts, chart, proc, depth, row, deferred_pass, sample_duration_idx); if (sample_duration_idx == (charts->this_sample_duration - 1)) { if (chart->redraw_needed > prev_redraw_needed) { /* Drawing bumped redraw_needed (like a layout change from widths changing), * so don't reset the counter to zero forcing the next redraw. TODO: this does cause * a small delay between width-affecting values showing and column widths adjusting to them, * resulting in a sort of eventually-consistent behavior. * We could trigger a redraw here immediately by basically jumping back to the start of * this function, but there are problems doing that as-is due to the stateful/incremental * relationship between the charts and vmon's sample. Rather than attacking that refactor * now, I'll leave it like this for now. */ chart->redraw_needed = 1; } else chart->redraw_needed = 0; } } /* consolidated version of chart text and graph rendering, makes snowflakes integration cleaner, this always gets called regardless of the charts mode */ static void maintain_chart(vwm_charts_t *charts, vwm_chart_t *chart, int deferred_pass) { assert(charts); assert(chart); /* let's make sure nobody's causing a deferred_pass=1 outside of defer_maintenance mode */ assert(!deferred_pass || charts->defer_maintenance); if (!chart->proc || !chart->proc->stores[VMON_STORE_PROC_STAT]) return; /* TODO: * A side effect of responding to window resizes in this function is there's a latency proportional to the current sample_interval. * Something to fix is to resize the charts when the window resizes. * However, simply resizing the charts is insufficient. Their contents need to be redrawn in the new dimensions, this is where it * gets annoying. The current maintain/draw_chart makes assumptions about being run from the periodic vmon per-process callback. * There needs to be a redraw mode added where draw_chart is just reconstructing the current state, which requires that we suppress * the phase advance in maintain_chart() and just enter draw_chart() to redraw everything for the same generation. * So this probably requires some tweaking of draw_chart() as well as maintain_chart(). I want to be able tocall mainta_charts() * from anywhere, and have it detect if it's being called on the same generation or if the generation has advanced. * For now, the monitors will just be a little latent in window resizes which is pretty harmless artifact. * XXX: ^^^ this comment is somewhat stale at this point now that deferred maintenance for headless mode happened, * furthermore this_sample_duration overlaps a bit with what's said above. */ /* deferred pass updates the arbitrarily reproducible overlays, not incrementally rendered graphs; this_sample_duration is irrelevant */ if (deferred_pass) { int row = 0, depth = 0; return draw_chart(charts, chart, chart->proc, &depth, &row, deferred_pass, 0 /* sample_duration_idx */); } for (unsigned i = 0; i < charts->this_sample_duration; i++) { int row = 0, depth = 0; vcr_advance_phase(chart->vcr, -1); /* change this to +1 to scroll the other direction */ /* recursively draw the monitored processes to the chart */ draw_chart(charts, chart, chart->proc, &depth, &row, 0 /* deferred_pass */, i); } } /* this callback gets invoked at sample time for every process we've explicitly monitored (not autofollowed children/threads) * It's where we update the cumulative data for all windows, including the graph masks, regardless of their visibility * It's also where we compose the graphs and text for visible windows into a picture ready for compositing with the window contents */ static void proc_sample_callback(vmon_t *vmon, void *sys_cb_arg, vmon_proc_t *proc, void *proc_cb_arg) { vwm_charts_t *charts = sys_cb_arg; vwm_chart_t *chart = proc_cb_arg; VWM_TRACE("proc=%p chart=%p", proc, chart); /* render the various always-updated charts, this is the component we do regardless of the charts mode and window visibility, * essentially the incrementally rendered/historic components */ maintain_chart(charts, chart, 0 /* deferred_pass */); /* XXX TODO: we used to mark repaint as being needed if this chart's window was mapped, but * since extricating charts from windows that's no longer convenient, and repaint is * always performed after a sample. Make sure the repainting isn't costly when nothing * charted is mapped (the case that code optimized) */ } /* reset snowflakes on the specified chart */ void vwm_chart_reset_snowflakes(vwm_charts_t *charts, vwm_chart_t *chart) { if (chart->snowflakes_cnt) { chart->snowflakes_cnt = 0; chart->redraw_needed = 1; } } /* (re)size the specified chart's visible dimensions */ int vwm_chart_set_visible_size(vwm_charts_t *charts, vwm_chart_t *chart, int width, int height) { chart->visible_width = width; chart->visible_height = height; if (vcr_resize_visible(chart->vcr, width, height) > 0) chart->redraw_needed = 1; return 1; } /* create an chart and start monitoring for the supplied pid */ vwm_chart_t * vwm_chart_create(vwm_charts_t *charts, int pid, int width, int height, const char *name) { vwm_chart_t *chart; chart = calloc(1, sizeof(vwm_chart_t)); if (!chart) { VWM_PERROR("Unable to allocate vwm_chart_t"); goto _err; } if (name) { chart->name = strdup(name); if (!chart->name) { VWM_PERROR("Unable to allocate name"); goto _err_free; } } /* TODO: make the columns interactively configurable @ runtime */ chart->columns[0] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_ROW, .side = VWM_SIDE_LEFT }; chart->columns[1] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_USER, .side = VWM_SIDE_LEFT }; chart->columns[2] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_SYS, .side = VWM_SIDE_LEFT }; chart->columns[3] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_WALL, .side = VWM_SIDE_LEFT }; chart->columns[4] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_TREE, .side = VWM_SIDE_LEFT }; chart->columns[5] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_ARGV, .side = VWM_SIDE_LEFT }; chart->columns[6] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_STATE, .side = VWM_SIDE_RIGHT }; chart->columns[7] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_PID, .side = VWM_SIDE_RIGHT }; chart->columns[8] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_WCHAN, .side = VWM_SIDE_RIGHT }; chart->columns[9] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_VWM, .side = VWM_SIDE_RIGHT }; chart->snowflake_columns[0] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_PID, .side = VWM_SIDE_LEFT }; chart->snowflake_columns[1] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_USER, .side = VWM_SIDE_LEFT }; chart->snowflake_columns[2] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_SYS, .side = VWM_SIDE_LEFT }; chart->snowflake_columns[3] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_WALL, .side = VWM_SIDE_LEFT }; chart->snowflake_columns[4] = (vwm_column_t){ .enabled = 1, .type = VWM_COLUMN_PROC_ARGV, .side = VWM_SIDE_LEFT }; /* add the client process to the monitoring hierarchy */ /* XXX note libvmon here maintains a unique callback for each unique callback+xwin pair, so multi-window processes work */ chart->proc = vmon_proc_monitor(&charts->vmon, NULL, pid, VMON_WANT_PROC_INHERIT, (void (*)(vmon_t *, void *, vmon_proc_t *, void *))proc_sample_callback, chart); if (!chart->proc) { VWM_ERROR("Unable to establish proc monitor"); goto _err_free; } /* FIXME: count_rows() isn't returning the right count sometimes (off by ~1), it seems to be related to racing with the automatic child monitoring */ /* the result is an extra row sometimes appearing below the process hierarchy */ chart->hierarchy_end = 1 + count_rows(chart->proc); chart->gen_last_composed = -1; chart->vcr = vcr_new(charts->vcr_backend, &chart->hierarchy_end, &chart->snowflakes_cnt); if (!vwm_chart_set_visible_size(charts, chart, width, height)) { VWM_ERROR("Unable to set initial chart size"); goto _err_unmonitor; } return chart; _err_unmonitor: vmon_proc_unmonitor(&charts->vmon, chart->proc, (void (*)(vmon_t *, void *, vmon_proc_t *, void *))proc_sample_callback, chart); _err_free: free(chart->name); free(chart); _err: return NULL; } /* stop monitoring and destroy the supplied chart */ void vwm_chart_destroy(vwm_charts_t *charts, vwm_chart_t *chart) { vmon_proc_unmonitor(&charts->vmon, chart->proc, (void (*)(vmon_t *, void *, vmon_proc_t *, void *))proc_sample_callback, chart); vcr_free(chart->vcr); free(chart->name); free(chart); } /* this composes the maintained chart into the base chart picture, this gets called from paint_all() on every repaint of xwin */ /* we noop the call if the gen_last_composed and proc->generation numbers match, indicating there's nothing new to compose. */ void vwm_chart_compose(vwm_charts_t *charts, vwm_chart_t *chart) { if (!chart->visible_width || !chart->visible_height) return; if (chart->gen_last_composed == chart->proc->generation) return; /* noop if no sampling occurred since last compose */ /* In deferred maintenance mode, we skip maintaining a bunch of layers until the compose happens. * Normally the layers are maintained incrementally with sampling so real-time visualized use cases * like vwm/vmon-xlib can always have a readily composed set of current layers to flatten/compose * into the output picture sourced during window rendering/compositing. * * But in offline viewing situations (vmon-png), especially for lower end embedded devices, the * libvmon sample rate tends to be orders of mangitude higher than the visualization rate. e.g. * sampling occurs @ 1Hz, with vmon snapshotting a png every half hour. In such situations it's * wasteful to be maintaining all layers on every libvmon sample. This is when deferred maintenance * should be used - it puts off maintaining layers which can be reproduced at any time, while still * maintaining the bare minimum needed for achieving correctness by compose time. All the layers * deferred between compose calls must still be maintained for compose to produce complete results, * so we do one last maintain_chart() call with deferred_pass=1, forcing maintenance of all layers. */ if (charts->defer_maintenance) maintain_chart(charts, chart, 1 /* deferred_pass */); chart->gen_last_composed = chart->proc->generation; /* remember this generation */ //VWM_TRACE("composing %p", chart); /* FIXME TODO: errors */ (void) vcr_compose(chart->vcr); } #ifdef USE_XLIB /* xdamage producing variant of the above for vwm composited WM use */ void vwm_chart_compose_xdamage(vwm_charts_t *charts, vwm_chart_t *chart, XserverRegion *res_damaged_region) { assert(charts); assert(chart); assert(res_damaged_region); vwm_chart_compose(charts, chart); /* damage the window to ensure the updated chart is drawn (TODO: this can be done more selectively/efficiently) */ /* TODO errors: */ (void) vcr_get_composed_xdamage(chart->vcr, res_damaged_region); } #endif /* render the chart into a picture at the specified coordinates and dimensions */ void vwm_chart_render(vwm_charts_t *charts, vwm_chart_t *chart, vcr_present_op_t op, vcr_dest_t *dest, int x, int y, int width, int height) { if (!chart->visible_width || !chart->visible_height) return; vcr_present(chart->vcr, op, dest, x, y, width, height); } /* increase the sample rate relative to current using the table of intervals */ void vwm_charts_rate_increase(vwm_charts_t *charts) { int i; assert(charts); for (i = 0; i < NELEMS(sampling_intervals); i++) { if (sampling_intervals[i] < charts->sampling_interval) { charts->sampling_interval = sampling_intervals[i]; break; } } } /* decrease the sample rate relative to current using the table of intervals */ void vwm_charts_rate_decrease(vwm_charts_t *charts) { int i; assert(charts); for (i = NELEMS(sampling_intervals) - 1; i >= 0; i--) { if (sampling_intervals[i] > charts->sampling_interval) { charts->sampling_interval = sampling_intervals[i]; break; } } } /* set an arbitrary sample rate rather than using one of the presets, 0 to pause */ void vwm_charts_rate_set(vwm_charts_t *charts, unsigned hertz) { assert(charts); /* XXX: note floating point divide by 0 simply results in infinity */ charts->sampling_interval = 1.0f / (float)hertz; } /* convenience function for returning the time delta as a seconds.fraction float */ static float delta(struct timeval *cur, struct timeval *prev) { struct timeval res; float delta; /* determine the # of whole.fractional seconds between prev and cur */ timersub(cur, prev, &res); delta = res.tv_sec; delta += (float)((float)res.tv_usec) / 1000000.0; return delta; } /* update the charts if necessary, return if updating occurred, and duration before another update needed in *desired_delay_us */ int vwm_charts_update(vwm_charts_t *charts, int *desired_delay_us) { float this_delta = 0.0f; int ret = 0; gettimeofday(&charts->maybe_sample, NULL); if (!charts->primed || (charts->sampling_interval == INFINITY && !charts->sampling_paused) || /* XXX this is kind of a kludge to get the 0 Hz indicator drawn before pausing */ (charts->sampling_interval != INFINITY && ((this_delta = delta(&charts->maybe_sample, &charts->this_sample)) >= charts->sampling_interval))) { vmon_sys_stat_t *sys_stat; /* automatically lower the sample rate if we can't keep up with the current sample rate */ if (charts->sampling_interval < INFINITY && charts->sampling_interval <= charts->prev_sampling_interval && this_delta >= (charts->sampling_interval * 1.5)) { /* adjust charts->this_sample_duration as needed since we've missed our deadline. * This is more of an issue in headless mode, especially when run on slower/embedded * devices, even worse when periodically snapshoting costly PNGs that may take * several seconds during which no sampling occurs. */ charts->this_sample_duration = (this_delta / charts->sampling_interval) + .5f /* rounded to int */; /* require > 1 contiguous drops before lowering the rate, tolerates spurious one-off stalls */ if (++charts->contiguous_drops > 2) vwm_charts_rate_decrease(charts); } else { charts->contiguous_drops = 0; charts->this_sample_duration = 1; /* ideally always 1, but > 1 when sample deadline missed (repeat sample) */ } VWM_TRACE("sample_duration=%u", charts->this_sample_duration); /* age the sys-wide sample data into "last" variables, before the new sample overwrites them. */ charts->last_sample = charts->this_sample; charts->this_sample = charts->maybe_sample; if ((sys_stat = charts->vmon.stores[VMON_STORE_SYS_STAT])) { charts->last_user_cpu = sys_stat->user; charts->last_system_cpu = sys_stat->system; charts->last_total = sys_stat->user + sys_stat->nice + sys_stat->system + sys_stat->idle + sys_stat->iowait + sys_stat->irq + sys_stat->softirq + sys_stat->steal + sys_stat->guest; charts->last_idle = sys_stat->idle; charts->last_iowait = sys_stat->iowait; } ret = vmon_sample(&charts->vmon); /* XXX: calls proc_sample_callback() for explicitly monitored processes after sampling their descendants */ /* XXX: also calls sample_callback() per invocation after sampling the sys wants */ charts->sampling_paused = (charts->sampling_interval == INFINITY); charts->prev_sampling_interval = charts->sampling_interval; /* "primed" is just a flag to ensure we always perform the first sample */ if (!charts->primed) charts->primed = 1; } /* TODO: make some effort to compute how long to sleep, but this is perfectly fine for now. */ *desired_delay_us = charts->sampling_interval == INFINITY ? -1 : charts->sampling_interval * 300.0; return ret; }