From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0D6713F54D8; Thu, 30 Jul 2026 09:01:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785402064; cv=none; b=I49SvO0MUeJGlLXlRo/0VS+TEH0ZbJ5GQBNiMjfJVpwSl1HcQ2K7rM5Bs1R+ytpx3dW4nbj2xW5ISpo5UfJqWiIoYzmfFuWjKvZhqADNPf2aQgQKSLY8M6lYKWpwfRNR7gJPw2yiXh5jAWmWN8WQLYhSPOqaf5Y6e05iPYvAB9o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785402064; c=relaxed/simple; bh=MjZwVIjdv5N8afM/wDndFDbhKYUmyX2k+Mhzo3j2rTA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FG12WptRHWhdNtoKB95EN7t1iMwVIvdlLbCVmWr7jXqKA4RXAARm1Q0wIcERK0sEbWV8SNeWWmhuUZjcN4Y7NysM/ORd50t8LUnAftaN4uT5f5lttBm2qqfaSQvNu7elqIVsf1H+NaWzGcsBatTezEFB1XNxXmrWqUEQd2s+6EA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=PhOZGNpt; arc=none smtp.client-ip=192.198.163.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="PhOZGNpt" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1785402063; x=1816938063; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=MjZwVIjdv5N8afM/wDndFDbhKYUmyX2k+Mhzo3j2rTA=; b=PhOZGNptA4/97ADosDUnKPv/uYKyjEdmPAOnkBCM+7qo6VGypXSC6eVn Yh2k5s4WPeM5QuwIQSa9aGCnA0RFxyH7A5/yvE1cLSXxdxh3str8JRfGy 3dLOS4m1XuS1kzKbXamtk/AMjcXHYPo6j8DvZUabgLgrXh5As12arunZa iviaAY0CLMmp3Tr+V5HG+0F+zaezZx7VH1MARCw/4BqJXNv6u3Em7bLS+ s5wWQW2bQXB1BkxOrodkCsjhpv9UImS0RBmJKIlSmO3uY3ay+MHOSmfha cAxp7DuvaEn2ATfBWjMMacfhX+Ta2A76Z4lTRha1hAUUttWBcbzoArpJo Q==; X-CSE-ConnectionGUID: FtGH4GCCQ52pQ8Yojqcw5A== X-CSE-MsgGUID: b9EQq8noRY28JrbQdizK/A== X-IronPort-AV: E=McAfee;i="6800,10657,11859"; a="111563549" X-IronPort-AV: E=Sophos;i="6.25,194,1779174000"; d="scan'208";a="111563549" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jul 2026 02:01:03 -0700 X-CSE-ConnectionGUID: K1aB+oYhQKyCk0Sf7NCNTg== X-CSE-MsgGUID: pHpGaFD2Rs6MsZ8eHYxpLw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,194,1779174000"; d="scan'208";a="260846541" Received: from linux-pnp-gnr-1.sh.intel.com ([10.239.83.186]) by orviesa009.jf.intel.com with ESMTP; 30 Jul 2026 02:00:59 -0700 From: Jiebin Sun To: Namhyung Kim Cc: acme@kernel.org, mingo@redhat.com, peterz@infradead.org, adrian.hunter@intel.com, alexander.shishkin@linux.intel.com, irogers@google.com, james.clark@linaro.org, jolsa@kernel.org, mark.rutland@arm.com, dapeng1.mi@linux.intel.com, thomas.falcon@intel.com, tianyou.li@intel.com, wangyang.guo@intel.com, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, Jiebin Sun Subject: [PATCH v5 v5 8/9] perf c2c: add function view browser UI and cacheline detail Date: Thu, 30 Jul 2026 17:05:20 +0800 Message-ID: <20260730090521.2206375-9-jiebin.sun@intel.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260730090521.2206375-1-jiebin.sun@intel.com> References: <20260730090521.2206375-1-jiebin.sun@intel.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add the browser front end: create/run/delete the hist_browser and add the title. The d shortcut opens the existing per-cacheline detail view for the selected level-3 cacheline. Level-3 entries retain the source cacheline index, so the shortcut can locate the original entry without relying on a potentially ambiguous virtual address. Require `iaddr` in the cacheline coalescing fields before building the view. Without it, the detail histograms may already have merged samples from different functions and cannot support reliable function attribution. Keep visible-row accounting local to the function view by wrapping the generic browser refresh callback and recounting the currently reachable hierarchy before each redraw. This keeps navigation correct when a level-1 row is collapsed while level-3 descendants remain expanded, without adding C2C-specific hooks to the shared hist_browser or enabling report_hierarchy and its incompatible ownership rules. Also handle Ctrl-C like the other function-view exit keys. Wire the builder into perf_c2c__browse_function_view() and refuse to run under report_hierarchy, whose hist_entry__delete() recursion would put the borrowed child references. Signed-off-by: Jiebin Sun Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Dapeng Mi Cc: Ian Rogers Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Falcon Reviewed-by: Tianyou Li Reviewed-by: Wangyang Guo --- tools/perf/ui/browsers/c2c-function.c | 239 +++++++++++++++++++++++++- 1 file changed, 236 insertions(+), 3 deletions(-) diff --git a/tools/perf/ui/browsers/c2c-function.c b/tools/perf/ui/browsers/c2c-function.c index 9a95355eedf5..44fb072fa937 100644 --- a/tools/perf/ui/browsers/c2c-function.c +++ b/tools/perf/ui/browsers/c2c-function.c @@ -15,6 +15,7 @@ #include #include #include +#include #include /* reallocarray */ #include #include @@ -49,6 +50,7 @@ static struct perf_c2c_ext c2c_ext; struct c2c_function_browser { struct hist_browser hb; + unsigned int (*orig_refresh)(struct ui_browser *browser); }; static inline u64 c2c_hitm_count(const struct c2c_stats *stats) @@ -93,6 +95,10 @@ static inline u64 hist_entry__iaddr(struct hist_entry *he) return he->ip; } +/* + * Hierarchy levels (by depth): L1 = read-side function, L2 = the writing + * function it contends with, L3 = the specific shared cacheline. + */ static inline bool hist_entry__is_cacheline(struct hist_entry *he) { return he->parent_he && he->parent_he->parent_he; /* level 3: cacheline */ @@ -701,6 +707,7 @@ c2c_function_hists__reinit(struct c2c_hists *c2c_hists, return function_hpp_list__parse(&c2c_hists->list, output, sort, env); } +/* Welford online merge of two "stats" (from util/stat.h) accumulators. */ static void c2c_stats_merge(struct stats *dest, const struct stats *src) { double delta; @@ -1440,6 +1447,58 @@ static void c2c_function__update_symbol_width(struct hist_entry *he) hists__set_col_len(hists, HISTC_SYMBOL, need); } +/* + * Count visible entries in @root, descending only through visible, unfolded + * parents. Match hists__filter_entries(), which drives generic browser + * navigation, so the count cannot include rows the browser skips. + */ +static u64 +c2c_function__nr_visible_rows(struct rb_root_cached *root, float min_pcnt) +{ + struct rb_node *nd; + u64 rows = 0; + + for (nd = rb_first_cached(root); nd; nd = rb_next(nd)) { + struct hist_entry *he = rb_entry(nd, struct hist_entry, rb_node); + + /* + * The generic refresh folds filtered parents and therefore hides + * their subtree. A percentage-rejected parent is merely skipped; + * if it is unfolded, qualifying descendants are still rendered. + */ + if (he->filtered) + continue; + + if (hist_entry__get_percent_limit(he) >= min_pcnt) + rows++; + if (he->has_children && he->unfolded) + rows += c2c_function__nr_visible_rows(&he->hroot_out, + min_pcnt); + } + return rows; +} + +static void +c2c_function_browser__update_nr_entries(struct c2c_function_browser *browser) +{ + u64 nr_entries; + + nr_entries = c2c_function__nr_visible_rows(&browser->hb.hists->entries, + browser->hb.min_pcnt); + browser->hb.nr_non_filtered_entries = nr_entries; + browser->hb.b.nr_entries = nr_entries; +} + +static unsigned int c2c_function_browser__refresh(struct ui_browser *ui_browser) +{ + struct hist_browser *hist_browser = container_of(ui_browser, struct hist_browser, b); + struct c2c_function_browser *browser; + + browser = container_of(hist_browser, struct c2c_function_browser, hb); + c2c_function_browser__update_nr_entries(browser); + return browser->orig_refresh(ui_browser); +} + /* * Prune writers with no stores, drop functions left with no contending * writer, sort the survivors by store count, then compute the global total. @@ -1512,7 +1571,7 @@ static void c2c_function_hists__reset(void) * L2: writing functions contending with each level-1 function * L3: shared cachelines for each function pair */ -static int __maybe_unused build_function_view_hierarchy(void) +static int build_function_view_hierarchy(void) { static const char output_fields[] = "cycles_percent,total_stores,symbol_view"; @@ -1591,8 +1650,182 @@ static int __maybe_unused build_function_view_hierarchy(void) return ret; } -int perf_c2c__browse_function_view(void) +static int c2c_function_browser__title(struct hist_browser *browser, + char *bf, size_t size) { - ui__warning("C2C function view is not implemented yet.\n"); + scnprintf(bf, size, + "Shared Data Functions Table (%" PRIu64 " entries, sorted on Cycles %%)", + browser->hists->nr_non_filtered_entries); return 0; } + +static struct c2c_function_browser *c2c_function_browser__new(struct hists *hists) +{ + struct c2c_function_browser *browser; + + if (!hists) + return NULL; + + browser = zalloc(sizeof(*browser)); + if (!browser) + return NULL; + + hist_browser__init(&browser->hb, hists); + browser->orig_refresh = browser->hb.b.refresh; + browser->hb.b.refresh = c2c_function_browser__refresh; + + browser->hb.title = c2c_function_browser__title; + browser->hb.c2c_filter = true; + browser->hb.show_headers = true; + /* Keep title line count consistent with forcing headers on. */ + browser->hb.b.extra_title_lines = hists->hpp_list->nr_header_lines; + browser->hb.min_pcnt = 0.0; + + /* + * Note: symbol_conf.report_hierarchy is deliberately left unset. + * The generic browser still descends into hroot_out children via + * rb_hierarchy_next()/can_goto_child(), which key off he->unfolded, + * so 'e'/'+' expands L1 -> L2 -> L3 correctly. Setting the flag would + * additionally make hist_entry__delete() recurse hroot_out and free + * each child, but our children borrow thread/ms (see + * c2c_child_entry__alloc()), so that would underflow their refcounts. + * Teardown is handled by c2c_he__free_hierarchy() instead. + */ + return browser; +} + +/* + * c2c_function_browser__delete - Free function browser + */ +static void c2c_function_browser__delete(struct c2c_function_browser *browser) +{ + free(browser); +} + +static int c2c_function_browser__browse_cacheline_detail(struct hist_entry *he_selection) +{ + struct c2c_hist_entry *c2c_he; + struct rb_node *nd; + + if (!he_selection || !he_selection->parent_he || + !he_selection->parent_he->parent_he) + return -1; + + c2c_he = container_of(he_selection, struct c2c_hist_entry, he); + + for (nd = rb_first_cached(&c2c.hists.hists.entries); nd; nd = rb_next(nd)) { + struct hist_entry *he = rb_entry(nd, struct hist_entry, rb_node); + struct c2c_hist_entry *cacheline_he; + + if (he->filtered) + continue; + + cacheline_he = container_of(he, struct c2c_hist_entry, he); + if (cacheline_he->hists && + cacheline_he->cacheline_idx == c2c_he->cacheline_idx) + return perf_c2c__browse_cacheline(he); + } + + return -1; +} + +static bool c2c_function__has_iaddr(void) +{ + const char *field = c2c.cl_sort; + + while (field && *field) { + const char *end = strchr(field, ','); + size_t len = end ? (size_t)(end - field) : strlen(field); + + if (len == sizeof("iaddr") - 1 && !strncmp(field, "iaddr", len)) + return true; + field = end ? end + 1 : NULL; + } + return false; +} + +/* + * perf_c2c__browse_function_view - Browse function view with TAB key support + * + * Returns: 0 on success, negative error code on failure + */ +int perf_c2c__browse_function_view(void) +{ + struct c2c_function_browser *sym_browser; + bool saved_use_callchain = symbol_conf.use_callchain; + int key, ret; + static const char help[] = + " d Display details for the selected level-3 cacheline\n" + " e/+ Expand/collapse the selected entry\n" + " TAB/ESC/q/^C Return to the cacheline view\n"; + + if (!c2c_function__has_iaddr()) { + ui__warning("The function view requires iaddr in --coalesce.\n"); + return -EINVAL; + } + + /* + * The level-2/3 children borrow thread/ms (see c2c_child_entry__alloc()) + * and are torn down by c2c_he__free_hierarchy(). report_hierarchy would + * make hist_entry__delete() recurse into hroot_out and put those borrowed + * refs (and call a NULL ops->free), so refuse to run if it is ever set. + */ + if (WARN_ON_ONCE(symbol_conf.report_hierarchy)) + return -EINVAL; + + /* Disable callchain before building so no callchain structs are allocated. */ + symbol_conf.use_callchain = false; + + ret = build_function_view_hierarchy(); + if (ret) { + ui__error("Failed to build function view hierarchy (ret=%d)\n", ret); + goto out; + } + + sym_browser = c2c_function_browser__new(&c2c_ext.function_hists.hists); + if (!sym_browser) { + ret = -ENOMEM; + goto out_reset; + } + + /* Reset abort key so we can receive Ctrl-C as a key. */ + SLang_reset_tty(); + SLang_init_tty(0, 0, 0); + SLtty_set_suspend_state(true); + + while (1) { + c2c_function_browser__update_nr_entries(sym_browser); + key = hist_browser__run(&sym_browser->hb, "? - help", true, 0); + + switch (key) { + case 'q': + case K_TAB: + case K_ESC: + case CTRL('c'): + goto browser_done; + case 'd': + /* Cacheline detail honors the user's callchain setting. */ + symbol_conf.use_callchain = saved_use_callchain; + c2c_function_browser__browse_cacheline_detail(sym_browser->hb.he_selection); + /* Preserve any toggle made in the detail view, then + * re-disable callchain for the function view. + */ + saved_use_callchain = symbol_conf.use_callchain; + symbol_conf.use_callchain = false; + break; + case '?': + ui_browser__help_window(&sym_browser->hb.b, help); + break; + default: + break; + } + } + +browser_done: + c2c_function_browser__delete(sym_browser); +out_reset: + c2c_function_hists__reset(); +out: + symbol_conf.use_callchain = saved_use_callchain; + return ret; +} -- 2.52.0