From patchwork Sat Feb 10 23:49:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?=C5=81ukasz_Bartosik?= X-Patchwork-Id: 199338 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:7300:50ea:b0:106:860b:bbdd with SMTP id r10csp1701067dyd; Sat, 10 Feb 2024 15:54:23 -0800 (PST) X-Forwarded-Encrypted: i=3; AJvYcCUw67AF4ChTSRgj2t+1P+2F3wMX3fjC9oeBJAxEetdBuIoDk4K+241aHLpaqgVpFWgzjLbDH1Vmbl9HV5M4nmAEbOwSeQ== X-Google-Smtp-Source: AGHT+IEcGKLftjKGkvIoSP93IHcvzx5KzLunTs04RhGWGTEjGrIiUDC3ljCFnQM891F3ohyFzYrM X-Received: by 2002:a05:6a21:3993:b0:19e:c777:5c60 with SMTP id ad19-20020a056a21399300b0019ec7775c60mr2817139pzc.21.1707609263644; Sat, 10 Feb 2024 15:54:23 -0800 (PST) ARC-Seal: i=2; a=rsa-sha256; t=1707609263; cv=pass; d=google.com; s=arc-20160816; b=QyTGUBIQ0xUvN9uEkJweAkQXZB1DyTdMgawOPnEDcflmEKzEiNv4NJeZBfgKhgYYfr fpxa1lV2sTQxj3ILI2uq84cDU9ekBO7fvQMWjaOiuxrvec9EHWcHbVQYXRfp1qvupG3E yRhM0SkIj5A1tFc1QyP1IPtlIY/3wuLXGYt7stR4KXIcZlvF6QY/vJb4EjhcDoMfxUVa oldUXp58sotC0D/hZw++muhSvvaml9p+JIxWKvC1PuK9wls7BXj9VhM06Rqc2bmDjlau zduDANnHDw0SOKY7AMGPEFM3JqaCzDMcsseMkJoT/4JSa0rTRh5s0TjXTbiLszxaI+dP 3Sog== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:mime-version:list-unsubscribe :list-subscribe:list-id:precedence:references:in-reply-to:message-id :date:subject:cc:to:from:dkim-signature; bh=VfKj9NP/58mMOcfaMc+gvbzTB/hMk+FrCsCCziFkNU8=; fh=Ua34lwqQZFQeaFEWke4h1aEPEI1AXKL2Y13wT0Ozu3A=; b=UJ8wdWcmSONnqubW2eJ1aqABD91wYnGJhKO0QesYEOoMY1FsUkp5mi+VoKKZ47FhoI wHjZZjN7IBdXvq9yAb5EjFnK78H9nDdXzXg0RGBplA513wGyX6URfFDiY8DWNmbeAF92 rs9A44DUcj/mr+0LGngIIUBK67jyed0dZw3h5U7qbWAvI4JaqM3Sa4uEKkKCc+WoEtU+ cx/tuG7rpYWGq9583B4R7tmRJEqYKgWz9oSFt2dRrVUh/qhmnAN1yReaTiaGzuytEN8L FNVieUaXra9LlLnt2uex7ahhvWS25H3ddAD3L49NOxYcwO0BTljjJErWP3jg0WKygICX shpg==; dara=google.com ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=NEc68OHh; arc=pass (i=1 spf=pass spfdomain=chromium.org dkim=pass dkdomain=chromium.org dmarc=pass fromdomain=chromium.org); spf=pass (google.com: domain of linux-kernel+bounces-60595-ouuuleilei=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) smtp.mailfrom="linux-kernel+bounces-60595-ouuuleilei=gmail.com@vger.kernel.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org X-Forwarded-Encrypted: i=2; AJvYcCV/7MM7RHUQQIhHFPowqjtLjIMpSqQmDkY65uDL1Zz89iI32DPJ7mES1SbrZ67JqTJpjufaZnKoWZtsxc6CwXcfas62gA== Received: from sv.mirrors.kernel.org (sv.mirrors.kernel.org. [139.178.88.99]) by mx.google.com with ESMTPS id bo6-20020a056a02038600b005dc4af11fedsi4214490pgb.887.2024.02.10.15.54.23 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 10 Feb 2024 15:54:23 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-60595-ouuuleilei=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99; Authentication-Results: mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=NEc68OHh; arc=pass (i=1 spf=pass spfdomain=chromium.org dkim=pass dkdomain=chromium.org dmarc=pass fromdomain=chromium.org); spf=pass (google.com: domain of linux-kernel+bounces-60595-ouuuleilei=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) smtp.mailfrom="linux-kernel+bounces-60595-ouuuleilei=gmail.com@vger.kernel.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sv.mirrors.kernel.org (Postfix) with ESMTPS id 25694283EAF for ; Sat, 10 Feb 2024 23:54:08 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id E1ABF612DE; Sat, 10 Feb 2024 23:50:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="NEc68OHh" Received: from mail-lf1-f53.google.com (mail-lf1-f53.google.com [209.85.167.53]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4AD0060BB8 for ; Sat, 10 Feb 2024 23:50:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.53 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707609053; cv=none; b=abckQW7o9xHfBjbo4iaQY3qgfUdzKCDGA20k5Gs6/os5c84i45L5DFv9MlKlgyYgUxcd7hD2oL6L3NEiVYxsceozyQbDPv9ROX9YyC1UzwAkSrsJSzDgXpR2mNAAVsZOV/v3N9wCgW88MDydzSfYrCwiXXKfewW1iaxEMBQf1vc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707609053; c=relaxed/simple; bh=YbEEGz+x4DGalh89sTCHjKKTuGvWKdWzObsdPhFL1wQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=GtQiTygtl2sUtW1hf2Ua1D0ErCMZYjYgp4I2sC0Xq4OT/CHawbEAkhBeXa4ICxTp+wcw2yQRKmhJ77Ar43JpJKvEPqoFyMMT3piWa8bFbaeNZPY7w45uYCa1El4nJiLjksTtad3BrCyfujyP/TLCfb4J2mPeSotZKgXfU4dYHdI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org; spf=pass smtp.mailfrom=chromium.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b=NEc68OHh; arc=none smtp.client-ip=209.85.167.53 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Received: by mail-lf1-f53.google.com with SMTP id 2adb3069b0e04-511531f03f6so2471383e87.0 for ; Sat, 10 Feb 2024 15:50:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1707609049; x=1708213849; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=VfKj9NP/58mMOcfaMc+gvbzTB/hMk+FrCsCCziFkNU8=; b=NEc68OHhXtTFO9xYinVIt81NO9lLr6U0JS87MQ1dGhZUiVuJmoX3p81Jy7Q2nZApXS NR0FnMH29PvJN0IE9PyPYu+1k7VVfcIOCoYXyS1v88XafT98mFaupl5spRmLtK/TCvJP eEbt/R4YdKUUueytTUHchHue6CMDOtAZ5hY78= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1707609049; x=1708213849; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=VfKj9NP/58mMOcfaMc+gvbzTB/hMk+FrCsCCziFkNU8=; b=AO5obeQEHMZuBqIswlHoZ8DufvI5nO0CYLOWGLPoCV5CDFluqXCLjmUwuFBzSp6Ep2 d4jJDE8U6DFHliFdpatqBmZwoWcZCowULxVxV70KxKOt5qzc9vGe0gTXAQ3tl4oCvsya 2sSeQUcORo2J8poYHmw07fenYX6wmGNVddR9Zq22y8f8LDp6pQUK6rFciETxJr2Cg2Y8 dzg2MmytJtV6+2/9RFGKRGUsPAu+uSresnusTIHa1E8w1aYSSEzeokkZlw7vfm6dx7Yz LKxVxB12aQqLp9imcPokCmI33UxUrNDZjIDMCNfp8NZlIThtSdi3jfxzEU3ZY0gdAX26 ELdQ== X-Forwarded-Encrypted: i=1; AJvYcCVv5VOnK1IitUVv0Ky+pTzOWnPA048Y0eUb3BvXeQlgHirEf4MFLxBsBn9w3qYwSj3MNqa4YiDvxg9Md07EDDRi2wWstPlo0++Ynlrt X-Gm-Message-State: AOJu0YyR/GNSZvyUfSgqy5qrvZPA2WtCAQeadg9xKda+yuy4Fs4IVqtQ bQ8+o2nt2u6EgXm4qqLKFlDonEx9M3kJUmezmo729gWeYPM4t2WuaK9/pvse X-Received: by 2002:a05:6512:3494:b0:511:29ee:83b8 with SMTP id v20-20020a056512349400b0051129ee83b8mr1734783lfr.62.1707609049402; Sat, 10 Feb 2024 15:50:49 -0800 (PST) X-Forwarded-Encrypted: i=1; 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 Received: from ukaszb-l.roam.corp.google.com (alfa56.extreme-net.one.pl. [213.77.89.56]) by smtp.gmail.com with ESMTPSA id o27-20020a056512051b00b0051179ae1846sm365561lfb.280.2024.02.10.15.50.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 10 Feb 2024 15:50:49 -0800 (PST) From: =?utf-8?q?=C5=81ukasz_Bartosik?= To: Jason Baron , Jim Cromie , Greg Kroah-Hartman , Andrew Morton , Kees Cook , Douglas Anderson Cc: Guenter Roeck , Yaniv Tzoreff , Benson Leung , Steven Rostedt , Vincent Whitchurch , Pekka Paalanen , Sean Paul , Daniel Vetter , Simon Ser , John Ogness , Petr Mladek , Sergey Senozhatsky , linux-kernel@vger.kernel.org, upstream@semihalf.com Subject: [PATCH v4 12/39] dyndbg: handle [+T]:buf_name.flags grammar Date: Sun, 11 Feb 2024 00:49:42 +0100 Message-ID: <20240210235009.2405808-13-ukaszb@chromium.org> X-Mailer: git-send-email 2.43.0.687.g38aa6559b0-goog In-Reply-To: <20240210235009.2405808-1-ukaszb@chromium.org> References: <20240210235009.2405808-1-ukaszb@chromium.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1790558091562538519 X-GMAIL-MSGID: 1790558091562538519 Add processing to handle the new [+T]:trace_name.flags grammar. The name provided sets selected callsites' trace-destinations: "0" - pr_debug()s are written to prdbg and devdbg trace events. name - pr_debug()s are written to named trace instance, if its already been open'd, else err. A user can provide trace destination name by following T flag with ":" and trace destination name, for example: echo "module thunderbolt =pT:tbt" > /dynamic_debug/control echo "module thunderbolt =lT:tbt.p" > /dynamic_debug/control Or user can provide only ":" and trace destination name, for example: echo "module thunderbolt =p:tbt" > /dynamic_debug/control echo "module thunderbolt =l:tbt.p" > /dynamic_debug/control In the former examples trace destination is set (":tbt") and write of pr_debug()s is enabled ("T"). In the latter examples only trace destination is set (":tbt") for later use. When T flag with argument is followed by other flag then the next flag has to be preceded with ".". When both T flag and ":" are provided together then ":" has to follow T flag in the form of "T:". Use of "." as a separator between flags allows a later patch to treat ',' as a space, which mostly eliminates the need to quote query/rules. And this in turn avoids quoting hassles: modprobe test_dynamic_debug dyndbg=class,D2_CORE,+p It is particularly good for passing boot-args into test-scripts. vng -p 4 -v \ -a test_dynamic_debug.dyndbg=class,D2_CORE,+p Signed-off-by: Łukasz Bartosik Co-developed-by: Jim Cromie Signed-off-by: Jim Cromie --- lib/dynamic_debug.c | 201 +++++++++++++++++++++++++++++++++++--------- 1 file changed, 162 insertions(+), 39 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 6668f265f2c3..8a81356c52b3 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -72,6 +72,7 @@ struct ddebug_iter { struct flag_settings { unsigned int flags; unsigned int mask; + unsigned int trace_dst; }; #define DD_OPEN_CMD "open" @@ -84,11 +85,17 @@ struct dd_private_tracebuf { int use_cnt; }; +#define DST_NOT_SET (-1) + /* - * Trace destination value 0 is reserved for writing - * debug logs to trace events (prdbg, devdbg), that - * is why buf[0] is not used and we traverse bitmap - * starting from bit 1 (bit 0 is also not used). + * When trace is enabled (T flag is set) and trace destination field + * value is in range [1..63] then debug logs will be written to trace + * instance whose name is stored in buf[trace destination].name, e.g. + * when trace destination value is 2 and buf[2].name is set to tbt then + * debug logs will be written to /tracing/instances/tbt. + * On the other hand trace destination value 0 is reserved for writing + * debug logs to trace events (prdbg, devdbg), that is why buf[0] is not + * used and we traverse bitmap starting from bit 1 (bit 0 is also not used). */ struct dd_tracebuf_tbl_info { struct dd_private_tracebuf buf[TRACE_DST_LAST]; @@ -126,6 +133,81 @@ static inline unsigned int get_trace_dst(const struct _ddebug *desc) return desc->ctrl.trace_dst; } +static int find_tr_instance(const char *name) +{ + int idx = 1; + + for_each_set_bit_from(idx, trc_tbl.bmap, trc_tbl.bmap_size) + if (!strcmp(trc_tbl.buf[idx].name, name)) + return idx; + + return -ENOENT; +} + +static const +char *read_colon_args(const char *str, struct flag_settings *modifiers) +{ + int len, idx = 0; + char *end; + + /* Check if trace destination was already set */ + if (modifiers->trace_dst != DST_NOT_SET) + return NULL; + /* + * When both T flag and ':' are provided then the T flag + * has to be followed by ':' in the form of 'T:'. + */ + if (modifiers->flags & _DPRINTK_FLAGS_TRACE && + *(str-1) != 'T') + return NULL; + + if (strchr(str, 'T')) + return NULL; + + str++; + end = strchr(str, '.'); + if (end) { + len = end - str; + *end = '\0'; + } else + len = strlen(str); + len -= 1; + + /* destination trace events */ + if (!strcmp(str, DD_TR_EVENT)) + goto end; + + idx = find_tr_instance(str); + if (idx < 0) + return NULL; +end: + modifiers->trace_dst = idx; + return end ? end : str + len; +} + +/* + * Maximum number of characters which are being displayed when + * printing trace instance name, longer names are truncated + */ +#define FLAG_COLON_ARG_LEN 24 + +static char *show_colon_args(struct dd_ctrl *ctrl, char *p) +{ + int n, len = FLAG_COLON_ARG_LEN; + const char *str; + + str = !ctrl->trace_dst ? DD_TR_EVENT : + trc_tbl.buf[ctrl->trace_dst].name; + + n = snprintf(p, len, "%s", str); + if (n >= len) { + strscpy(&p[len-4], "...", 4); + n = len - 1; + } + + return n < 0 ? p : p + n; +} + /* Return the path relative to source root */ static inline const char *trim_prefix(const char *path) { @@ -137,9 +219,28 @@ static inline const char *trim_prefix(const char *path) return path + skip; } -static const struct { unsigned flag:8; char opt_char; } opt_array[] = { +typedef const char* (*read_flag_args_f)(const char *, struct flag_settings *); +typedef char* (*show_flag_args_f)(struct dd_ctrl *, char *); + +static const struct +{ + unsigned flag:8; + char opt_char; + bool always_show; + read_flag_args_f read_args; + show_flag_args_f show_args; +} opt_array[] = { { _DPRINTK_FLAGS_PRINTK, 'p' }, { _DPRINTK_FLAGS_TRACE, 'T' }, + /* + * We don't reserve a flag for ':'. The ':' is used to provide + * trace destination name and when provided together with T flag + * it enables output to the trace destination. When ':' is provided + * without T flag then it sets trace destination for a callsite for + * future use. When both T flag and ':'are provided together then + * ':' has to follow T flag in the form of 'T:'. + */ + { _DPRINTK_FLAGS_NONE, ':', true, read_colon_args, show_colon_args }, { _DPRINTK_FLAGS_INCL_MODNAME, 'm' }, { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' }, { _DPRINTK_FLAGS_INCL_SOURCENAME, 's' }, @@ -148,22 +249,31 @@ static const struct { unsigned flag:8; char opt_char; } opt_array[] = { { _DPRINTK_FLAGS_NONE, '_' }, }; -struct flagsbuf { char buf[ARRAY_SIZE(opt_array)+1]; }; +struct ctrlbuf { char buf[ARRAY_SIZE(opt_array)+FLAG_COLON_ARG_LEN+1]; }; /* format a string into buf[] which describes the _ddebug's flags */ -static char *ddebug_describe_flags(unsigned int flags, struct flagsbuf *fb) +static char *ddebug_describe_ctrl(struct dd_ctrl *ctrl, struct ctrlbuf *cb) { - char *p = fb->buf; + show_flag_args_f show_args = NULL; + char *p = cb->buf; int i; for (i = 0; i < ARRAY_SIZE(opt_array); ++i) - if (flags & opt_array[i].flag) + if (ctrl->flags & opt_array[i].flag || + opt_array[i].always_show) { + if (show_args) + *p++ = '.'; *p++ = opt_array[i].opt_char; - if (p == fb->buf) + show_args = opt_array[i].show_args; + if (show_args) + p = show_args(ctrl, p); + } + + if (p == cb->buf) *p++ = '_'; *p = '\0'; - return fb->buf; + return cb->buf; } #define vnpr_info(lvl, fmt, ...) \ @@ -221,17 +331,6 @@ static bool dd_good_trace_name(const char *str) return true; } -static int find_tr_instance(const char *name) -{ - int idx = 1; - - for_each_set_bit_from(idx, trc_tbl.bmap, trc_tbl.bmap_size) - if (!strcmp(trc_tbl.buf[idx].name, name)) - return idx; - - return -ENOENT; -} - static int handle_trace_open_cmd(const char *arg) { struct dd_private_tracebuf *buf; @@ -383,7 +482,7 @@ static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table cons * Search the tables for _ddebug's which match the given `query' and * apply the `flags' and `mask' to them. Returns number of matching * callsites, normally the same as number of changes. If verbose, - * logs the changes. Takes ddebug_lock. + * logs the changes. */ static int ddebug_change(const struct ddebug_query *query, struct flag_settings *modifiers) @@ -391,13 +490,12 @@ static int ddebug_change(const struct ddebug_query *query, int i; struct ddebug_table *dt; unsigned int nfound = 0; + struct ctrlbuf cbuf, nbuf; struct dd_ctrl nctrl = {0}; - struct flagsbuf fbuf, nbuf; struct ddebug_class_map *map = NULL; int __outvar valid_class; /* search for matching ddebugs */ - mutex_lock(&ddebug_lock); list_for_each_entry(dt, &ddebug_tables, link) { /* match against the module name */ @@ -458,7 +556,8 @@ static int ddebug_change(const struct ddebug_query *query, nfound++; nctrl.flags = (get_flags(dp) & modifiers->mask) | modifiers->flags; - if (!memcmp(&nctrl, get_ctrl(dp), sizeof(struct dd_ctrl))) + nctrl.trace_dst = modifiers->trace_dst; + if (!memcmp(&nctrl, get_ctrl(dp), sizeof(nctrl))) continue; #ifdef CONFIG_JUMP_LABEL if (get_flags(dp) & _DPRINTK_FLAGS_ENABLED) { @@ -471,13 +570,12 @@ static int ddebug_change(const struct ddebug_query *query, v4pr_info("changed %s:%d [%s]%s %s => %s\n", trim_prefix(dp->filename), dp->lineno, dt->mod_name, dp->function, - ddebug_describe_flags(get_flags(dp), &fbuf), - ddebug_describe_flags(nctrl.flags, &nbuf)); + ddebug_describe_ctrl(&dp->ctrl, &cbuf), + ddebug_describe_ctrl(&nctrl, &nbuf)); update_tr_dst(dp, &nctrl); set_ctrl(dp, &nctrl); } } - mutex_unlock(&ddebug_lock); if (!nfound && verbose) pr_info("no matches for query\n"); @@ -698,6 +796,7 @@ static int ddebug_parse_query(char *words[], int nwords, */ static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers) { + read_flag_args_f read_args; int op, i; switch (*str) { @@ -716,6 +815,12 @@ static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers) for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) { if (*str == opt_array[i].opt_char) { modifiers->flags |= opt_array[i].flag; + read_args = opt_array[i].read_args; + if (read_args) { + str = read_args(str, modifiers); + if (!str) + return -EINVAL; + } break; } } @@ -724,7 +829,7 @@ static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers) return -EINVAL; } } - v3pr_info("flags=0x%x\n", modifiers->flags); + v3pr_info("flags=0x%x, trace_dest=0x%x\n", modifiers->flags, modifiers->trace_dst); /* calculate final flags, mask based upon op */ switch (op) { @@ -747,7 +852,7 @@ static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers) static int ddebug_exec_query(char *query_string, const char *modname) { - struct flag_settings modifiers = {}; + struct flag_settings modifiers = { .trace_dst = DST_NOT_SET }; struct ddebug_query query = {}; #define MAXWORDS 9 int nwords, nfound; @@ -763,20 +868,38 @@ static int ddebug_exec_query(char *query_string, const char *modname) if (is_dd_trace_cmd(words[0])) return ddebug_parse_cmd(words, nwords-1); - /* check flags 1st (last arg) so query is pairs of spec,val */ - if (ddebug_parse_flags(words[nwords-1], &modifiers)) { - pr_err("flags parse failed\n"); - return -EINVAL; - } if (ddebug_parse_query(words, nwords-1, &query, modname)) { pr_err("query parse failed\n"); return -EINVAL; } + + /* + * Both ddebug_parse_flags and ddebug_change have to be run + * with locking because ddebug_parse_flags->read_T_args verifies + * if a requested trace instance is opened. Next ddebug_change + * sets the requested trace instance as output for debug logs of + * callsite(s) which matched a query. Because ddebug_proc_write + * function can be called concurrently then without locking we + * could for example run into a scenario where ddebug_change uses + * a trace instance which is already closed. + */ + mutex_lock(&ddebug_lock); + + /* check flags 1st (last arg) so query is pairs of spec,val */ + if (ddebug_parse_flags(words[nwords-1], &modifiers)) { + pr_err("flags parse failed\n"); + goto err; + } + /* actually go and implement the change */ nfound = ddebug_change(&query, &modifiers); - vpr_info_dq(&query, nfound ? "applied" : "no-match"); + mutex_unlock(&ddebug_lock); + vpr_info_dq(&query, nfound ? "applied" : "no-match"); return nfound; +err: + mutex_unlock(&ddebug_lock); + return -EINVAL; } /* handle multiple queries in query string, continue on error, return @@ -1466,7 +1589,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p) { struct ddebug_iter *iter = m->private; struct _ddebug *dp = p; - struct flagsbuf flags; + struct ctrlbuf cbuf; char const *class; if (p == SEQ_START_TOKEN) { @@ -1478,7 +1601,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p) seq_printf(m, "%s:%u [%s]%s =%s \"", trim_prefix(dp->filename), dp->lineno, iter->table->mod_name, dp->function, - ddebug_describe_flags(get_flags(dp), &flags)); + ddebug_describe_ctrl(&dp->ctrl, &cbuf)); seq_escape_str(m, dp->format, ESCAPE_SPACE, "\t\r\n\""); seq_puts(m, "\"");