Add a DDB "show files" command to list the current open file list, some

state about each open file, and identify the first process in the process
table that references the file.  This is helpful in debugging leaks of
file descriptors.

MFC after:	1 week
This commit is contained in:
Robert Watson 2005-11-10 10:42:50 +00:00
parent b89ad281dc
commit b4e507aafa
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=152272

View File

@ -38,6 +38,7 @@
__FBSDID("$FreeBSD$");
#include "opt_compat.h"
#include "opt_ddb.h"
#include <sys/param.h>
#include <sys/systm.h>
@ -69,6 +70,8 @@ __FBSDID("$FreeBSD$");
#include <vm/uma.h>
#include <ddb/ddb.h>
static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table");
static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader",
"file desc to leader structures");
@ -2466,6 +2469,76 @@ sysctl_kern_file(SYSCTL_HANDLER_ARGS)
SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD,
0, 0, sysctl_kern_file, "S,xfile", "Entire file table");
#ifdef DDB
/*
* For the purposes of debugging, generate a human-readable string for the
* file type.
*/
static const char *
file_type_to_name(short type)
{
switch (type) {
case 0:
return ("zero");
case DTYPE_VNODE:
return ("vnod");
case DTYPE_SOCKET:
return ("sock");
case DTYPE_PIPE:
return ("pipe");
case DTYPE_FIFO:
return ("fifo");
case DTYPE_CRYPTO:
return ("crpt");
default:
return ("unkn");
}
}
/*
* For the purposes of debugging, identify a process (if any, perhaps one of
* many) that references the passed file in its file descriptor array. Return
* NULL if none.
*/
static struct proc *
file_to_first_proc(struct file *fp)
{
struct filedesc *fdp;
struct proc *p;
int n;
LIST_FOREACH(p, &allproc, p_list) {
if (p->p_state == PRS_NEW)
continue;
fdp = p->p_fd;
if (fdp == NULL)
continue;
for (n = 0; n < fdp->fd_nfiles; n++) {
if (fp == fdp->fd_ofiles[n])
return (p);
}
}
return (NULL);
}
DB_SHOW_COMMAND(files, db_show_files)
{
struct file *fp;
struct proc *p;
db_printf("%9s %4s %9s %9s %6s %9s %6s %12s\n", "File", "Type",
"Data", "Flag", "Count", "Vnode", "FPid", "FCmd");
LIST_FOREACH(fp, &filehead, f_list) {
p = file_to_first_proc(fp);
db_printf("%9p %4s %9p 0x%09x %6d %9p %6d %12s\n", fp,
file_type_to_name(fp->f_type), fp->f_data, fp->f_flag,
fp->f_count, fp->f_vnode, p != NULL ? p->p_pid : -1,
p != NULL ? p->p_comm : "-");
}
}
#endif
SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW,
&maxfilesperproc, 0, "Maximum files allowed open per process");