From nobody Wed Dec 31 13:02:33 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7392AC4167D for ; Fri, 3 Nov 2023 13:10:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377598AbjKCNKp (ORCPT ); Fri, 3 Nov 2023 09:10:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48820 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233674AbjKCNKc (ORCPT ); Fri, 3 Nov 2023 09:10:32 -0400 Received: from mail-lf1-x12c.google.com (mail-lf1-x12c.google.com [IPv6:2a00:1450:4864:20::12c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5AA62D4E for ; Fri, 3 Nov 2023 06:10:27 -0700 (PDT) Received: by mail-lf1-x12c.google.com with SMTP id 2adb3069b0e04-507f1c29f25so2508219e87.1 for ; Fri, 03 Nov 2023 06:10:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=semihalf.com; s=google; t=1699017025; x=1699621825; 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=uOUDhCvR7O/HItpGyWqotIRwbNv9xPIlLL6yVbWMeYY=; b=OoXi3RDYNRkK0YjSeLNAigmYbP17lRyy3F6hWfKfdA09H4WuPQFeAeiYoneRQ2giyz JpUnSHHyTScQIYYOlR05vJnnwd+b7Y3BrdUdOxlYtxFUG1hI3tAZsdhkPHWYnWZhIGhh LHvUF0VUUju7HaHVi/fyG+FAA/A7zi2LiiWTOtFc7FlTFSTeM6hokoltMOb3paiL1rgZ JvzclF3ULiBdNLTF86HTwznOr96PMp5IeX4F1dgSsjlyef8QXxX43UZMx33/QC1Ni8ot 4iCw2JaVdwZ4hBDcY2ybQqc03kMYeDyfGgbAy3dBPH0oyVkDKobwdPtx6kD8qlbnBOgx JitQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699017025; x=1699621825; 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=uOUDhCvR7O/HItpGyWqotIRwbNv9xPIlLL6yVbWMeYY=; b=Z7dcxbaWMWuGNKOfrZ3IAKGvCo0KtbOQqVvuFab12bM1Sl3oP7HZe0WeQg2CZxPJWQ NYXjNI7aaflijk6CDpniqE8OhQWeU8XDij5NlicfFbI2tuRyrtWpu1Rv1b9Kmz44mcen fDhFmn62Bi11245EHGDasF7VIrxBLuulcvTigVHCsjqiyk5IIcEuQAu6DXGWw4FHdKZD bMqg6sO1+iFtQ79nSw4VOXQ46RDN9wk13wYhtDnlTf9j7MiGYIBBmOJ3wTYTyocapjUh HIcrRE2GSmAZlQ121IGAoDXefjCIS65AGRv7zCwm1poUhivmHLEoMbC4mUMxazlEYewF E/kA== X-Gm-Message-State: AOJu0Yyia8rfmJskU5J950rL8N9WzKYQwMoN3ecO/njZjcOU580s30jd MhHz/eXvzZsGwkXyr9CpctNh X-Google-Smtp-Source: AGHT+IHF5aYNXQAYCxmcX3r+x3IpwrCfoPEIek1akbRf2gESDru4XOg7w2GOPvQH7+yVAXjPBMOORg== X-Received: by 2002:ac2:4e08:0:b0:509:2b57:32e with SMTP id e8-20020ac24e08000000b005092b57032emr12843892lfr.8.1699017025546; Fri, 03 Nov 2023 06:10:25 -0700 (PDT) Received: from ukaszb-l.wifi.semihalf.net ([83.142.187.85]) by smtp.gmail.com with ESMTPSA id f21-20020ac25335000000b00507a69a4799sm216336lfh.270.2023.11.03.06.10.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Nov 2023 06:10:25 -0700 (PDT) From: =?UTF-8?q?=C5=81ukasz=20Bartosik?= To: Jason Baron , Jim Cromie , Andrew Morton , Kees Cook , Douglas Anderson Cc: Guenter Roeck , Yaniv Tzoreff , Benson Leung , Steven Rostedt , Vincent Whitchurch , Pekka Paalanen , Sean Paul , Daniel Vetter , linux-kernel@vger.kernel.org, upstream@semihalf.com Subject: [PATCH v1 10/12] dyndbg: add processing of T(race) flag argument Date: Fri, 3 Nov 2023 14:10:09 +0100 Message-Id: <20231103131011.1316396-11-lb@semihalf.com> X-Mailer: git-send-email 2.38.3 In-Reply-To: <20231103131011.1316396-1-lb@semihalf.com> References: <20231103131011.1316396-1-lb@semihalf.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add processing of argument provided to T(race) flag. The argument value determines destination of debug logs: 0 - debug logs will be written to prdbg and devdbg trace events [1..255] - debug logs will be written to trace instance A user can provide trace destination by folowing T flag with ":" and trace destination value in range [0..255], for example: echo "module thunderbolt =3DpT:7" > /sys/kernel/debug/dynamic_debug/control echo "module thunderbolt =3DlT:7,p" > /sys/kernel/debug/dynamic_debug/contr= ol When T flag with argument is followed by other flags then the next flag has to be preceded with ",". When no value is provided trace destination defaults to 0, for example: echo "module thunderbolt =3DT" > /sys/kernel/debug/dynamic_debug/control echo "module thunderbolt =3DlTp" > /sys/kernel/debug/dynamic_debug/control Signed-off-by: =C5=81ukasz Bartosik --- lib/dynamic_debug.c | 105 +++++++++++++++++++++++++++++++++++++------- 1 file changed, 90 insertions(+), 15 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 3218ab078a76..c5cd28e74a02 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -71,6 +71,7 @@ struct ddebug_iter { struct flag_settings { unsigned int flags; unsigned int mask; + unsigned int trace_dst; }; =20 static DEFINE_MUTEX(ddebug_lock); @@ -111,9 +112,67 @@ static inline const char *trim_prefix(const char *path) return path + skip; } =20 -static const struct { unsigned flag:8; char opt_char; } opt_array[] =3D { +typedef const char* (*read_flag_args_f)(const char *, struct flag_settings= *); +typedef char* (*show_flag_args_f)(struct dd_ctrl *, char *); + +/* + * Maximum number of characters representing value + * of flag T argument in human readable form - ":255," + */ +#define FLAG_T_ARGS_LEN 5 + +static const +char *read_T_args(const char *str, struct flag_settings *modifiers) +{ + char *end, args[FLAG_T_ARGS_LEN]; + int len; + + if (*(str+1) !=3D ':') + return str; + + str +=3D 2; + end =3D strchr(str, ','); + if (end && *(end + 1) =3D=3D '\0') + return NULL; + + if (end) + len =3D end - str; + else + len =3D strlen(str); + + if (len > FLAG_T_ARGS_LEN - 1) + return NULL; + + memcpy(args, str, len); + args[len] =3D '\0'; + if (kstrtouint(args, 10, &modifiers->trace_dst) < 0) + return NULL; + + if (modifiers->trace_dst > TRACE_DST_MAX) + return NULL; + + return end ? end : str + len; +} + +char *show_T_args(struct dd_ctrl *ctrl, char *p) +{ + int n; + + n =3D snprintf(p, FLAG_T_ARGS_LEN, ":%u", ctrl->trace_dst); + WARN_ONCE(n < 0, "printing T flag args value failed\n"); + + return n < 0 ? p : p + n; +} + +static const struct +{ + unsigned flag:8; + char opt_char; + read_flag_args_f read_args; + show_flag_args_f show_args; +} opt_array[] =3D { { _DPRINTK_FLAGS_PRINTK, 'p' }, - { _DPRINTK_FLAGS_TRACE, 'T' }, + { _DPRINTK_FLAGS_TRACE, 'T', read_T_args, show_T_args}, { _DPRINTK_FLAGS_INCL_MODNAME, 'm' }, { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' }, { _DPRINTK_FLAGS_INCL_SOURCENAME, 's' }, @@ -122,22 +181,30 @@ static const struct { unsigned flag:8; char opt_char;= } opt_array[] =3D { { _DPRINTK_FLAGS_NONE, '_' }, }; =20 -struct flagsbuf { char buf[ARRAY_SIZE(opt_array)+1]; }; +struct ctrlbuf { char buf[ARRAY_SIZE(opt_array)+FLAG_T_ARGS_LEN+1]; }; =20 /* 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 =3D fb->buf; + show_flag_args_f show_args =3D NULL; + char *p =3D cb->buf; int i; =20 for (i =3D 0; i < ARRAY_SIZE(opt_array); ++i) - if (flags & opt_array[i].flag) + if (ctrl->flags & opt_array[i].flag) { + if (show_args) + *p++ =3D ','; *p++ =3D opt_array[i].opt_char; - if (p =3D=3D fb->buf) + show_args =3D opt_array[i].show_args; + if (show_args) + p =3D show_args(ctrl, p); + } + + if (p =3D=3D cb->buf) *p++ =3D '_'; *p =3D '\0'; =20 - return fb->buf; + return cb->buf; } =20 #define vnpr_info(lvl, fmt, ...) \ @@ -202,7 +269,7 @@ static int ddebug_change(const struct ddebug_query *que= ry, struct ddebug_table *dt; unsigned int nfound =3D 0; struct dd_ctrl nctrl =3D {0}; - struct flagsbuf fbuf, nbuf; + struct ctrlbuf cbuf, nbuf; struct ddebug_class_map *map =3D NULL; int __outvar valid_class; =20 @@ -268,7 +335,8 @@ static int ddebug_change(const struct ddebug_query *que= ry, nfound++; =20 nctrl.flags =3D (get_flags(dp) & modifiers->mask) | modifiers->flags; - if (!memcmp(&nctrl, get_ctrl(dp), sizeof(struct dd_ctrl))) + nctrl.trace_dst =3D modifiers->trace_dst; + if (!memcmp(&nctrl, get_ctrl(dp), sizeof(nctrl))) continue; #ifdef CONFIG_JUMP_LABEL if (get_flags(dp) & _DPRINTK_FLAGS_ENABLED) { @@ -281,8 +349,8 @@ static int ddebug_change(const struct ddebug_query *que= ry, v4pr_info("changed %s:%d [%s]%s %s =3D> %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)); set_ctrl(dp, &nctrl); } } @@ -507,6 +575,7 @@ static int ddebug_parse_query(char *words[], int nwords, */ static int ddebug_parse_flags(const char *str, struct flag_settings *modif= iers) { + read_flag_args_f read_args; int op, i; =20 switch (*str) { @@ -525,6 +594,12 @@ static int ddebug_parse_flags(const char *str, struct = flag_settings *modifiers) for (i =3D ARRAY_SIZE(opt_array) - 1; i >=3D 0; i--) { if (*str =3D=3D opt_array[i].opt_char) { modifiers->flags |=3D opt_array[i].flag; + read_args =3D opt_array[i].read_args; + if (read_args) { + str =3D read_args(str, modifiers); + if (!str) + return -EINVAL; + } break; } } @@ -533,7 +608,7 @@ static int ddebug_parse_flags(const char *str, struct f= lag_settings *modifiers) return -EINVAL; } } - v3pr_info("flags=3D0x%x\n", modifiers->flags); + v3pr_info("flags=3D0x%x, trace dest=3D0x%x\n", modifiers->flags, modifier= s->trace_dst); =20 /* calculate final flags, mask based upon op */ switch (op) { @@ -1257,7 +1332,7 @@ static int ddebug_proc_show(struct seq_file *m, void = *p) { struct ddebug_iter *iter =3D m->private; struct _ddebug *dp =3D p; - struct flagsbuf flags; + struct ctrlbuf cbuf; char const *class; =20 if (p =3D=3D SEQ_START_TOKEN) { @@ -1269,7 +1344,7 @@ static int ddebug_proc_show(struct seq_file *m, void = *p) seq_printf(m, "%s:%u [%s]%s =3D%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, "\""); =20 --=20 2.42.0.869.gea05f2083d-goog