cregit-Linux how code gets into the kernel

Release 4.18 lib/dynamic_debug.c

Directory: lib
/*
 * lib/dynamic_debug.c
 *
 * make pr_debug()/dev_dbg() calls runtime configurable based upon their
 * source module.
 *
 * Copyright (C) 2008 Jason Baron <jbaron@redhat.com>
 * By Greg Banks <gnb@melbourne.sgi.com>
 * Copyright (c) 2008 Silicon Graphics Inc.  All Rights Reserved.
 * Copyright (C) 2011 Bart Van Assche.  All Rights Reserved.
 * Copyright (C) 2013 Du, Changbin <changbin.du@gmail.com>
 */


#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kallsyms.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/list.h>
#include <linux/sysctl.h>
#include <linux/ctype.h>
#include <linux/string.h>
#include <linux/parser.h>
#include <linux/string_helpers.h>
#include <linux/uaccess.h>
#include <linux/dynamic_debug.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
#include <linux/jump_label.h>
#include <linux/hardirq.h>
#include <linux/sched.h>
#include <linux/device.h>
#include <linux/netdevice.h>

extern struct _ddebug __start___verbose[];
extern struct _ddebug __stop___verbose[];


struct ddebug_table {
	
struct list_head link;
	
const char *mod_name;
	
unsigned int num_ddebugs;
	
struct _ddebug *ddebugs;
};


struct ddebug_query {
	
const char *filename;
	
const char *module;
	
const char *function;
	
const char *format;
	

unsigned int first_lineno, last_lineno;
};


struct ddebug_iter {
	
struct ddebug_table *table;
	
unsigned int idx;
};

static DEFINE_MUTEX(ddebug_lock);
static LIST_HEAD(ddebug_tables);

static int verbose;
module_param(verbose, int, 0644);

/* Return the path relative to source root */

static inline const char *trim_prefix(const char *path) { int skip = strlen(__FILE__) - strlen("lib/dynamic_debug.c"); if (strncmp(path, __FILE__, skip)) skip = 0; /* prefix mismatch, don't skip */ return path + skip; }

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Jim Cromie48100.00%1100.00%
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static struct { unsigned flag:8; char opt_char; } opt_array[] = { { _DPRINTK_FLAGS_PRINT, 'p' }, { _DPRINTK_FLAGS_INCL_MODNAME, 'm' }, { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' }, { _DPRINTK_FLAGS_INCL_LINENO, 'l' }, { _DPRINTK_FLAGS_INCL_TID, 't' }, { _DPRINTK_FLAGS_NONE, '_' }, }; /* format a string into buf[] which describes the _ddebug's flags */
static char *ddebug_describe_flags(struct _ddebug *dp, char *buf, size_t maxlen) { char *p = buf; int i; BUG_ON(maxlen < 6); for (i = 0; i < ARRAY_SIZE(opt_array); ++i) if (dp->flags & opt_array[i].flag) *p++ = opt_array[i].opt_char; if (p == buf) *p++ = '_'; *p = '\0'; return buf; }

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Jason Baron6265.26%133.33%
Bart Van Assche3132.63%133.33%
Jim Cromie22.11%133.33%
Total95100.00%3100.00%

#define vpr_info(fmt, ...) \ do { \ if (verbose) \ pr_info(fmt, ##__VA_ARGS__); \ } while (0)
static void vpr_info_dq(const struct ddebug_query *query, const char *msg) { /* trim any trailing newlines */ int fmtlen = 0; if (query->format) { fmtlen = strlen(query->format); while (fmtlen && query->format[fmtlen - 1] == '\n') fmtlen--; } vpr_info("%s: func=\"%s\" file=\"%s\" module=\"%s\" format=\"%.*s\" lineno=%u-%u\n", msg, query->function ? query->function : "", query->filename ? query->filename : "", query->module ? query->module : "", fmtlen, query->format ? query->format : "", query->first_lineno, query->last_lineno); }

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Joe Perches11095.65%150.00%
Jim Cromie54.35%150.00%
Total115100.00%2100.00%

/* * 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. */
static int ddebug_change(const struct ddebug_query *query, unsigned int flags, unsigned int mask) { int i; struct ddebug_table *dt; unsigned int newflags; unsigned int nfound = 0; char flagbuf[10]; /* search for matching ddebugs */ mutex_lock(&ddebug_lock); list_for_each_entry(dt, &ddebug_tables, link) { /* match against the module name */ if (query->module && !match_wildcard(query->module, dt->mod_name)) continue; for (i = 0; i < dt->num_ddebugs; i++) { struct _ddebug *dp = &dt->ddebugs[i]; /* match against the source filename */ if (query->filename && !match_wildcard(query->filename, dp->filename) && !match_wildcard(query->filename, kbasename(dp->filename)) && !match_wildcard(query->filename, trim_prefix(dp->filename))) continue; /* match against the function */ if (query->function && !match_wildcard(query->function, dp->function)) continue; /* match against the format */ if (query->format && !strstr(dp->format, query->format)) continue; /* match against the line number range */ if (query->first_lineno && dp->lineno < query->first_lineno) continue; if (query->last_lineno && dp->lineno > query->last_lineno) continue; nfound++; newflags = (dp->flags & mask) | flags; if (newflags == dp->flags) continue; #ifdef HAVE_JUMP_LABEL if (dp->flags & _DPRINTK_FLAGS_PRINT) { if (!(flags & _DPRINTK_FLAGS_PRINT)) static_branch_disable(&dp->key.dd_key_true); } else if (flags & _DPRINTK_FLAGS_PRINT) static_branch_enable(&dp->key.dd_key_true); #endif dp->flags = newflags; vpr_info("changed %s:%d [%s]%s =%s\n", trim_prefix(dp->filename), dp->lineno, dt->mod_name, dp->function, ddebug_describe_flags(dp, flagbuf, sizeof(flagbuf))); } } mutex_unlock(&ddebug_lock); if (!nfound && verbose) pr_info("no matches for query\n"); return nfound; }

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Jason Baron33390.00%220.00%
Jim Cromie246.49%550.00%
Changbin Du102.70%110.00%
Joe Perches20.54%110.00%
Andy Shevchenko10.27%110.00%
Total370100.00%10100.00%

/* * Split the buffer `buf' into space-separated words. * Handles simple " and ' quoting, i.e. without nested, * embedded or escaped \". Return the number of words * or <0 on error. */
static int ddebug_tokenize(char *buf, char *words[], int maxwords) { int nwords = 0; while (*buf) { char *end; /* Skip leading whitespace */ buf = skip_spaces(buf); if (!*buf) break; /* oh, it was trailing whitespace */ if (*buf == '#') break; /* token starts comment, skip rest of line */ /* find `end' of word, whitespace separated or quoted */ if (*buf == '"' || *buf == '\'') { int quote = *buf++; for (end = buf; *end && *end != quote; end++) ; if (!*end) { pr_err("unclosed quote: %s\n", buf); return -EINVAL; /* unclosed quote */ } } else { for (end = buf; *end && !isspace(*end); end++) ; BUG_ON(end == buf); } /* `buf' is start of word, `end' is one past its end */ if (nwords == maxwords) { pr_err("too many words, legal max <=%d\n", maxwords); return -EINVAL; /* ran out of words[] before bytes */ } if (*end) *end++ = '\0'; /* terminate the word */ words[nwords++] = buf; buf = end; } if (verbose) { int i; pr_info("split into words:"); for (i = 0; i < nwords; i++) pr_cont(" \"%s\"", words[i]); pr_cont("\n"); } return nwords; }

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Greg Banks12552.30%114.29%
Jason Baron7933.05%114.29%
Jim Cromie2912.13%342.86%
Joe Perches41.67%114.29%
André Goddard Rosa20.84%114.29%
Total239100.00%7100.00%

/* * Parse a single line number. Note that the empty string "" * is treated as a special case and converted to zero, which * is later treated as a "don't care" value. */
static inline int parse_lineno(const char *str, unsigned int *val) { BUG_ON(str == NULL); if (*str == '\0') { *val = 0; return 0; } if (kstrtouint(str, 10, val) < 0) { pr_err("bad line-number: %s\n", str); return -EINVAL; } return 0; }

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Jason Baron5071.43%133.33%
Jim Cromie1318.57%133.33%
Andrey Ryabinin710.00%133.33%
Total70100.00%3100.00%


static int check_set(const char **dest, char *src, char *name) { int rc = 0; if (*dest) { rc = -EINVAL; pr_err("match-spec:%s val:%s overridden by %s\n", name, *dest, src); } *dest = src; return rc; }

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Jim Cromie5698.25%150.00%
Joe Perches11.75%150.00%
Total57100.00%2100.00%

/* * Parse words[] as a ddebug query specification, which is a series * of (keyword, value) pairs chosen from these possibilities: * * func <function-name> * file <full-pathname> * file <base-filename> * module <module-name> * format <escaped-string-to-find-in-format> * line <lineno> * line <first-lineno>-<last-lineno> // where either may be empty * * Only 1 of each type is allowed. * Returns 0 on success, <0 on error. */
static int ddebug_parse_query(char *words[], int nwords, struct ddebug_query *query, const char *modname) { unsigned int i; int rc = 0; /* check we have an even number of words */ if (nwords % 2 != 0) { pr_err("expecting pairs of match-spec <value>\n"); return -EINVAL; } memset(query, 0, sizeof(*query)); if (modname) /* support $modname.dyndbg=<multiple queries> */ query->module = modname; for (i = 0; i < nwords; i += 2) { if (!strcmp(words[i], "func")) { rc = check_set(&query->function, words[i+1], "func"); } else if (!strcmp(words[i], "file")) { rc = check_set(&query->filename, words[i+1], "file"); } else if (!strcmp(words[i], "module")) { rc = check_set(&query->module, words[i+1], "module"); } else if (!strcmp(words[i], "format")) { string_unescape_inplace(words[i+1], UNESCAPE_SPACE | UNESCAPE_OCTAL | UNESCAPE_SPECIAL); rc = check_set(&query->format, words[i+1], "format"); } else if (!strcmp(words[i], "line")) { char *first = words[i+1]; char *last = strchr(first, '-'); if (query->first_lineno || query->last_lineno) { pr_err("match-spec: line used 2x\n"); return -EINVAL; } if (last) *last++ = '\0'; if (parse_lineno(first, &query->first_lineno) < 0) return -EINVAL; if (last) { /* range <first>-<last> */ if (parse_lineno(last, &query->last_lineno) < 0) return -EINVAL; /* special case for last lineno not specified */ if (query->last_lineno == 0) query->last_lineno = UINT_MAX; if (query->last_lineno < query->first_lineno) { pr_err("last-line:%d < 1st-line:%d\n", query->last_lineno, query->first_lineno); return -EINVAL; } } else { query->last_lineno = query->first_lineno; } } else { pr_err("unknown keyword \"%s\"\n", words[i]); return -EINVAL; } if (rc) return rc; } vpr_info_dq(query, "parsed"); return 0; }

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Jason Baron28663.70%218.18%
Jim Cromie11024.50%436.36%
Andy Shevchenko163.56%19.09%
Randy Dunlap153.34%19.09%
Andrey Ryabinin122.67%19.09%
Joe Perches102.23%218.18%
Total449100.00%11100.00%

/* * Parse `str' as a flags specification, format [-+=][p]+. * Sets up *maskp and *flagsp to be used when changing the * flags fields of matched _ddebug's. Returns 0 on success * or <0 on error. */
static int ddebug_parse_flags(const char *str, unsigned int *flagsp, unsigned int *maskp) { unsigned flags = 0; int op = '=', i; switch (*str) { case '+': case '-': case '=': op = *str++; break; default: pr_err("bad flag-op %c, at start of %s\n", *str, str); return -EINVAL; } vpr_info("op='%c'\n", op); for (; *str ; ++str) { for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) { if (*str == opt_array[i].opt_char) { flags |= opt_array[i].flag; break; } } if (i < 0) { pr_err("unknown flag '%c' in \"%s\"\n", *str, str); return -EINVAL; } } vpr_info("flags=0x%x\n", flags); /* calculate final *flagsp, *maskp according to mask and op */ switch (op) { case '=': *maskp = 0; *flagsp = flags; break; case '+': *maskp = ~0U; *flagsp = flags; break; case '-': *maskp = ~flags; *flagsp = 0; break; } vpr_info("*flagsp=0x%x *maskp=0x%x\n", *flagsp, *maskp); return 0; }

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Jason Baron15668.72%120.00%
Bart Van Assche4318.94%120.00%
Jim Cromie2511.01%240.00%
Joe Perches31.32%120.00%
Total227100.00%5100.00%


static int ddebug_exec_query(char *query_string, const char *modname) { unsigned int flags = 0, mask = 0; struct ddebug_query query; #define MAXWORDS 9 int nwords, nfound; char *words[MAXWORDS]; nwords = ddebug_tokenize(query_string, words, MAXWORDS); if (nwords <= 0) { pr_err("tokenize failed\n"); return -EINVAL; } /* check flags 1st (last arg) so query is pairs of spec,val */ if (ddebug_parse_flags(words[nwords-1], &flags, &mask)) { 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; } /* actually go and implement the change */ nfound = ddebug_change(&query, flags, mask); vpr_info_dq(&query, nfound ? "applied" : "no-match"); return nfound; }

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Thomas Renninger6742.41%120.00%
Jim Cromie5736.08%360.00%
Jason Baron3421.52%120.00%
Total158100.00%5100.00%

/* handle multiple queries in query string, continue on error, return last error or number of matching callsites. Module name is either in param (for boot arg) or perhaps in query string. */
static int ddebug_exec_queries(char *query, const char *modname) { char *split; int i, errs = 0, exitcode = 0, rc, nfound = 0; for (i = 0; query; query = split) { split = strpbrk(query, ";\n"); if (split) *split++ = '\0'; query = skip_spaces(query); if (!query || !*query || *query == '#') continue; vpr_info("query %d: \"%s\"\n", i, query); rc = ddebug_exec_query(query, modname); if (rc < 0) { errs++; exitcode = rc; } else { nfound += rc; } i++; } vpr_info("processed %d queries, with %d matches, %d errs\n", i, nfound, errs); if (exitcode) return exitcode; return nfound; }

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Jim Cromie15096.77%360.00%
Thomas Renninger31.94%120.00%
Joe Perches21.29%120.00%
Total155100.00%5100.00%

#define PREFIX_SIZE 64
static int remaining(int wrote) { if (PREFIX_SIZE - wrote > 0) return PREFIX_SIZE - wrote; return 0; }

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Jason Baron2392.00%133.33%
Joe Perches14.00%133.33%
Bart Van Assche14.00%133.33%
Total25100.00%3100.00%


static char *dynamic_emit_prefix(const struct _ddebug *desc, char *buf) { int pos_after_tid; int pos = 0; *buf = '\0'; if (desc->flags & _DPRINTK_FLAGS_INCL_TID) { if (in_interrupt()) pos += snprintf(buf + pos, remaining(pos), "<intr> "); else pos += snprintf(buf + pos, remaining(pos), "[%d] ", task_pid_vnr(current)); } pos_after_tid = pos; if (desc->flags & _DPRINTK_FLAGS_INCL_MODNAME) pos += snprintf(buf + pos, remaining(pos), "%s:", desc->modname); if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME) pos += snprintf(buf + pos, remaining(pos), "%s:", desc->function); if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO) pos += snprintf(buf + pos, remaining(pos), "%d:", desc->lineno); if (pos - pos_after_tid) pos += snprintf(buf + pos, remaining(pos), " "); if (pos >= PREFIX_SIZE) buf[PREFIX_SIZE - 1] = '\0'; return buf; }

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Bart Van Assche9846.45%120.00%
Jason Baron8942.18%120.00%
Joe Perches2411.37%360.00%
Total211100.00%5100.00%


void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...) { va_list args; struct va_format vaf; char buf[PREFIX_SIZE]; BUG_ON(!descriptor); BUG_ON(!fmt); va_start(args, fmt); vaf.fmt = fmt; vaf.va = &args; printk(KERN_DEBUG "%s%pV", dynamic_emit_prefix(descriptor, buf), &vaf); va_end(args); }

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Joe Perches4250.60%360.00%
Jason Baron3137.35%120.00%
Bart Van Assche1012.05%120.00%
Total83100.00%5100.00%

EXPORT_SYMBOL(__dynamic_pr_debug);
void __dynamic_dev_dbg(struct _ddebug *descriptor, const struct device *dev, const char *fmt, ...) { struct va_format vaf; va_list args; BUG_ON(!descriptor); BUG_ON(!fmt); va_start(args, fmt); vaf.fmt = fmt; vaf.va = &args; if (!dev) { printk(KERN_DEBUG "(NULL device *): %pV", &vaf); } else { char buf[PREFIX_SIZE]; dev_printk_emit(LOGLEVEL_DEBUG, dev, "%s%s %s: %pV", dynamic_emit_prefix(descriptor, buf), dev_driver_string(dev), dev_name(dev), &vaf); } va_end(args); }

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Joe Perches11897.52%685.71%
Jason Baron32.48%114.29%
Total121100.00%7100.00%

EXPORT_SYMBOL(__dynamic_dev_dbg); #ifdef CONFIG_NET
void __dynamic_netdev_dbg(struct _ddebug *descriptor, const struct net_device *dev, const char *fmt, ...) { struct va_format vaf; va_list args; BUG_ON(!descriptor); BUG_ON(!fmt); va_start(args, fmt); vaf.fmt = fmt; vaf.va = &args; if (dev && dev->dev.parent) { char buf[PREFIX_SIZE]; dev_printk_emit(LOGLEVEL_DEBUG, dev->dev.parent, "%s%s %s %s%s: %pV", dynamic_emit_prefix(descriptor, buf), dev_driver_string(dev->dev.parent), dev_name(dev->dev.parent), netdev_name(dev), netdev_reg_state(dev), &vaf); } else if (dev) { printk(KERN_DEBUG "%s%s: %pV", netdev_name(dev), netdev_reg_state(dev), &vaf); } else { printk(KERN_DEBUG "(NULL net_device): %pV", &vaf); } va_end(args); }

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Joe Perches8347.70%457.14%
Jason Baron7945.40%228.57%
Veaceslav Falico126.90%114.29%
Total174100.00%7100.00%

EXPORT_SYMBOL(__dynamic_netdev_dbg); #endif #define DDEBUG_STRING_SIZE 1024 static __initdata char ddebug_setup_string[DDEBUG_STRING_SIZE];
static __init int ddebug_setup_query(char *str) { if (strlen(str) >= DDEBUG_STRING_SIZE) { pr_warn("ddebug boot param string too large\n"); return 0; } strlcpy(ddebug_setup_string, str, DDEBUG_STRING_SIZE); return 1; }

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Thomas Renninger3788.10%133.33%
Jim Cromie49.52%133.33%
Joe Perches12.38%133.33%
Total42100.00%3100.00%

__setup("ddebug_query=", ddebug_setup_query); /* * File_ops->write method for <debugfs>/dynamic_debug/control. Gathers the * command text from userspace, parses and executes it. */ #define USER_BUF_PAGE 4096
static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf, size_t len, loff_t *offp) { char *tmpbuf; int ret; if (len == 0) return 0; if (len > USER_BUF_PAGE - 1) { pr_warn("expected <%d bytes into control\n", USER_BUF_PAGE); return -E2BIG; } tmpbuf = memdup_user_nul(ubuf, len); if (IS_ERR(tmpbuf)) return PTR_ERR(tmpbuf); vpr_info("read %d bytes from userspace\n", (int)len); ret = ddebug_exec_queries(tmpbuf, NULL); kfree(tmpbuf); if (ret < 0) return ret; *offp += len; return len; }

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Jason Baron5141.13%112.50%
Jim Cromie3729.84%450.00%
Thomas Renninger2923.39%112.50%
Al Viro64.84%112.50%
Joe Perches10.81%112.50%
Total124100.00%8100.00%

/* * Set the iterator to point to the first _ddebug object * and return a pointer to that first object. Returns * NULL if there are no _ddebugs at all. */
static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter) { if (list_empty(&ddebug_tables)) { iter->table = NULL; iter->idx = 0; return NULL; } iter->table = list_entry(ddebug_tables.next, struct ddebug_table, link); iter->idx = 0; return &iter->table->ddebugs[iter->idx]; }

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Jason Baron73100.00%1100.00%
Total73100.00%1100.00%

/* * Advance the iterator to point to the next _ddebug * object from the one the iterator currently points at, * and returns a pointer to the new _ddebug. Returns * NULL if the iterator has seen all the _ddebugs. */
static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter) { if (iter->table == NULL) return NULL; if (++iter->idx == iter->table->num_ddebugs) { /* iterate to next table */ iter->idx = 0; if (list_is_last(&iter->table->link, &ddebug_tables)) { iter->table = NULL; return NULL; } iter->table = list_entry(iter->table->link.next, struct ddebug_table, link); } return &iter->table->ddebugs[iter->idx]; }

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Jason Baron105100.00%1100.00%
Total105100.00%1100.00%

/* * Seq_ops start method. Called at the start of every * read() call from userspace. Takes the ddebug_lock and * seeks the seq_file's iterator to the given position. */
static void *ddebug_proc_start(struct seq_file *m, loff_t *pos) { struct ddebug_iter *iter = m->private; struct _ddebug *dp; int n = *pos; vpr_info("called m=%p *pos=%lld\n", m, (unsigned long long)*pos); mutex_lock(&ddebug_lock); if (!n) return SEQ_START_TOKEN; if (n < 0) return NULL; dp = ddebug_iter_first(iter); while (dp != NULL && --n > 0) dp = ddebug_iter_next(iter); return dp; }

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Jason Baron10098.04%133.33%
Joe Perches10.98%133.33%
Jim Cromie10.98%133.33%
Total102100.00%3100.00%

/* * Seq_ops next method. Called several times within a read() * call from userspace, with ddebug_lock held. Walks to the * next _ddebug object with a special case for the header line. */
static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos) { struct ddebug_iter *iter = m->private; struct _ddebug *dp; vpr_info("called m=%p p=%p *pos=%lld\n", m, p, (unsigned long long)*pos); if (p == SEQ_START_TOKEN) dp = ddebug_iter_first(iter); else dp = ddebug_iter_next(iter); ++*pos; return dp; }

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Jason Baron7797.47%133.33%
Jim Cromie11.27%133.33%
Joe Perches11.27%133.33%
Total79100.00%3100.00%

/* * Seq_ops show method. Called several times within a read() * call from userspace, with ddebug_lock held. Formats the * current _ddebug as a single human-readable line, with a * special case for the header line. */
static int ddebug_proc_show(struct seq_file *m, void *p) { struct ddebug_iter *iter = m->private; struct _ddebug *dp = p; char flagsbuf[10]; vpr_info("called m=%p p=%p\n", m, p); if (p == SEQ_START_TOKEN) { seq_puts(m, "# filename:lineno [module]function flags format\n"); return 0; } seq_printf(m, "%s:%u [%s]%s =%s \"", trim_prefix(dp->filename), dp->lineno, iter->table->mod_name, dp->function, ddebug_describe_flags(dp, flagsbuf, sizeof(flagsbuf))); seq_escape(m, dp->format, "\t\r\n\""); seq_puts(m, "\"\n"); return 0; }

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Jason Baron11894.40%120.00%
Jim Cromie64.80%360.00%
Joe Perches10.80%120.00%
Total125100.00%5100.00%

/* * Seq_ops stop method. Called at the end of each read() * call from userspace. Drops ddebug_lock. */
static void ddebug_proc_stop(struct seq_file *m, void *p) { vpr_info("called m=%p p=%p\n", m, p); mutex_unlock(&ddebug_lock); }

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Jason Baron2893.33%133.33%
Joe Perches13.33%133.33%
Jim Cromie13.33%133.33%
Total30100.00%3100.00%

static const struct seq_operations ddebug_proc_seqops = { .start = ddebug_proc_start, .next = ddebug_proc_next, .show = ddebug_proc_show, .stop = ddebug_proc_stop }; /* * File_ops->open method for <debugfs>/dynamic_debug/control. Does * the seq_file setup dance, and also creates an iterator to walk the * _ddebugs. Note that we create a seq_file always, even for O_WRONLY * files where it's not needed, as doing so simplifies the ->release * method. */
static int ddebug_proc_open(struct inode *inode, struct file *file) { vpr_info("called\n"); return seq_open_private(file, &ddebug_proc_seqops, sizeof(struct ddebug_iter)); }

Contributors

PersonTokensPropCommitsCommitProp
Jason Baron2877.78%125.00%
Rob Jones616.67%125.00%
Joe Perches12.78%125.00%
Jim Cromie12.78%125.00%
Total36100.00%4100.00%

static const struct file_operations ddebug_proc_fops = { .owner = THIS_MODULE, .open = ddebug_proc_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release_private, .write = ddebug_proc_write }; /* * Allocate a new ddebug_table for the given module * and add it to the global list. */
int ddebug_add_module(struct _ddebug *tab, unsigned int n, const char *name) { struct ddebug_table *dt; const char *new_name; dt = kzalloc(sizeof(*dt), GFP_KERNEL); if (dt == NULL) return -ENOMEM; new_name = kstrdup_const(name, GFP_KERNEL); if (new_name == NULL) { kfree(dt); return -ENOMEM; } dt->mod_name = new_name; dt->num_ddebugs = n; dt->ddebugs = tab; mutex_lock(&ddebug_lock); list_add_tail(&dt->link, &ddebug_tables); mutex_unlock(&ddebug_lock); vpr_info("%u debug prints in module %s\n", n, dt->mod_name); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jason Baron13097.74%133.33%
Rasmus Villemoes21.50%133.33%
Jim Cromie10.75%133.33%
Total133100.00%3100.00%

EXPORT_SYMBOL_GPL(ddebug_add_module); /* helper for ddebug_dyndbg_(boot|module)_param_cb */
static int ddebug_dyndbg_param_cb(char *param, char *val, const char *modname, int on_err) { char *sep; sep = strchr(param, '.'); if (sep) { /* needed only for ddebug_dyndbg_boot_param_cb */ *sep = '\0'; modname = param; param = sep + 1; } if (strcmp(param, "dyndbg")) return on_err; /* determined by caller */ ddebug_exec_queries((val ? val : "+p"), modname); return 0; /* query failure shouldnt stop module load */ }

Contributors

PersonTokensPropCommitsCommitProp
Jim Cromie87100.00%3100.00%
Total87100.00%3100.00%

/* handle both dyndbg and $module.dyndbg params at boot */
static int ddebug_dyndbg_boot_param_cb(char *param, char *val, const char *unused, void *arg) { vpr_info("%s=\"%s\"\n", param, val); return ddebug_dyndbg_param_cb(param, val, NULL, 0); }

Contributors

PersonTokensPropCommitsCommitProp
Jim Cromie4090.91%266.67%
Luis R. Rodriguez49.09%133.33%
Total44100.00%3100.00%

/* * modprobe foo finds foo.params in boot-args, strips "foo.", and * passes them to load_module(). This callback gets unknown params, * processes dyndbg params, rejects others. */
int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *module) { vpr_info("module: %s %s=\"%s\"\n", module, param, val); return ddebug_dyndbg_param_cb(param, val, module, -ENOENT); }

Contributors

PersonTokensPropCommitsCommitProp
Jim Cromie42100.00%2100.00%
Total42100.00%2100.00%


static void ddebug_table_free(struct ddebug_table *dt) { list_del_init(&dt->link); kfree_const(dt->mod_name); kfree(dt); }

Contributors

PersonTokensPropCommitsCommitProp
Jason Baron3096.77%150.00%
Rasmus Villemoes13.23%150.00%
Total31100.00%2100.00%

/* * Called in response to a module being unloaded. Removes * any ddebug_table's which point at the module. */
int ddebug_remove_module(const char *mod_name) { struct ddebug_table *dt, *nextdt; int ret = -ENOENT; vpr_info("removing module \"%s\"\n", mod_name); mutex_lock(&ddebug_lock); list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) { if (!strcmp(dt->mod_name, mod_name)) { ddebug_table_free(dt); ret = 0; } } mutex_unlock(&ddebug_lock); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Jason Baron7896.30%125.00%
Joe Perches11.23%125.00%
Jim Cromie11.23%125.00%
Yehuda Sadeh Weinraub11.23%125.00%
Total81100.00%4100.00%

EXPORT_SYMBOL_GPL(ddebug_remove_module);
static void ddebug_remove_all_tables(void) { mutex_lock(&ddebug_lock); while (!list_empty(&ddebug_tables)) { struct ddebug_table *dt = list_entry(ddebug_tables.next, struct ddebug_table, link); ddebug_table_free(dt); } mutex_unlock(&ddebug_lock); }

Contributors

PersonTokensPropCommitsCommitProp
Jason Baron53100.00%1100.00%
Total53100.00%1100.00%

static __initdata int ddebug_init_success;
static int __init dynamic_debug_init_debugfs(void) { struct dentry *dir, *file; if (!ddebug_init_success) return -ENODEV; dir = debugfs_create_dir("dynamic_debug", NULL); if (!dir) return -ENOMEM; file = debugfs_create_file("control", 0644, dir, NULL, &ddebug_proc_fops); if (!file) { debugfs_remove(dir); return -ENOMEM; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jason Baron6582.28%150.00%
Thomas Renninger1417.72%150.00%
Total79100.00%2100.00%


static int __init dynamic_debug_init(void) { struct _ddebug *iter, *iter_start; const char *modname = NULL; char *cmdline; int ret = 0; int n = 0, entries = 0, modct = 0; int verbose_bytes = 0; if (__start___verbose == __stop___verbose) { pr_warn("_ddebug table is empty in a CONFIG_DYNAMIC_DEBUG build\n"); return 1; } iter = __start___verbose; modname = iter->modname; iter_start = iter; for (; iter < __stop___verbose; iter++) { entries++; verbose_bytes += strlen(iter->modname) + strlen(iter->function) + strlen(iter->filename) + strlen(iter->format); if (strcmp(modname, iter->modname)) { modct++; ret = ddebug_add_module(iter_start, n, modname); if (ret) goto out_err; n = 0; modname = iter->modname; iter_start = iter; } n++; } ret = ddebug_add_module(iter_start, n, modname); if (ret) goto out_err; ddebug_init_success = 1; vpr_info("%d modules, %d entries and %d bytes in ddebug tables, %d bytes in (readonly) verbose section\n", modct, entries, (int)(modct * sizeof(struct ddebug_table)), verbose_bytes + (int)(__stop___verbose - __start___verbose)); /* apply ddebug_query boot param, dont unload tables on err */ if (ddebug_setup_string[0] != '\0') { pr_warn("ddebug_query param name is deprecated, change it to dyndbg\n"); ret = ddebug_exec_queries(ddebug_setup_string, NULL); if (ret < 0) pr_warn("Invalid ddebug boot param %s\n", ddebug_setup_string); else pr_info("%d changes by ddebug_query\n", ret); } /* now that ddebug tables are loaded, process all boot args * again to find and activate queries given in dyndbg params. * While this has already been done for known boot params, it * ignored the unknown ones (dyndbg in particular). Reusing * parse_args avoids ad-hoc parsing. This will also attempt * to activate queries for not-yet-loaded modules, which is * slightly noisy if verbose, but harmless. */ cmdline = kstrdup(saved_command_line, GFP_KERNEL); parse_args("dyndbg params", cmdline, NULL, 0, 0, 0, NULL, &ddebug_dyndbg_boot_param_cb); kfree(cmdline); return 0; out_err: ddebug_remove_all_tables(); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jim Cromie15547.69%753.85%
Jason Baron11033.85%17.69%
Thomas Renninger5316.31%215.38%
Joe Perches51.54%215.38%
Luis R. Rodriguez20.62%17.69%
Total325100.00%13100.00%

/* Allow early initialization for boot messages via boot param */ early_initcall(dynamic_debug_init); /* Debugfs setup must be done later */ fs_initcall(dynamic_debug_init_debugfs);

Overall Contributors

PersonTokensPropCommitsCommitProp
Jason Baron249554.31%711.67%
Jim Cromie93920.44%2135.00%
Joe Perches4289.32%1016.67%
Bart Van Assche2365.14%11.67%
Thomas Renninger2284.96%35.00%
Greg Banks1262.74%11.67%
Greg Kroah-Hartman330.72%23.33%
Andy Shevchenko200.44%23.33%
Andrey Ryabinin190.41%23.33%
Randy Dunlap150.33%11.67%
Changbin Du140.30%11.67%
Veaceslav Falico120.26%11.67%
Luis R. Rodriguez60.13%11.67%
Al Viro60.13%11.67%
Rob Jones60.13%11.67%
Rasmus Villemoes40.09%11.67%
Tejun Heo30.07%11.67%
André Goddard Rosa20.04%11.67%
Masatake YAMATO10.02%11.67%
Yehuda Sadeh Weinraub10.02%11.67%
Total4594100.00%60100.00%
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