pmap: new applet. +1k.

pmap is a tool used to look at processes' memory maps, normally found
in procps package. It provides more readable and easily sortable output
(one line per mapping) from  maps/smaps files in /proc/PID/.  This would
help in debugging memory usage issues, especially on devices where lots
of typing is not a viable option.

This patch does'n implement -d and -A command line options of GNU pmap,
since those are not that must have features and I was afraid of going
blind from looking at its code.

The implementation takes smaps scanning part out of procps_scan() function
and moves it into procps_read_smaps(), which does more detailed processing
of a single PID's smaps data.

Signed-off-by: Alexander Shishkin <virtuoso@slind.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Alexander Shishkin 2010-08-28 23:20:34 +02:00 committed by Denys Vlasenko
parent 74c992af5c
commit 0834a6d3b9
4 changed files with 251 additions and 67 deletions

View File

@ -1387,6 +1387,29 @@ enum { COMM_LEN = TASK_COMM_LEN };
enum { COMM_LEN = 16 };
# endif
#endif
struct smaprec {
unsigned long mapped_rw;
unsigned long mapped_ro;
unsigned long shared_clean;
unsigned long shared_dirty;
unsigned long private_clean;
unsigned long private_dirty;
unsigned long stack;
unsigned long smap_pss, smap_swap;
unsigned long smap_size;
unsigned long smap_start;
char smap_mode[5];
char *smap_name;
};
#if !ENABLE_PMAP
#define procps_read_smaps(pid, total, cb, data) \
procps_read_smaps(pid, total)
#endif
int FAST_FUNC procps_read_smaps(pid_t pid, struct smaprec *total,
void (*cb)(struct smaprec *, void *), void *data);
typedef struct procps_status_t {
DIR *dir;
IF_FEATURE_SHOW_THREADS(DIR *task_dir;)
@ -1415,13 +1438,7 @@ typedef struct procps_status_t {
#endif
unsigned tty_major,tty_minor;
#if ENABLE_FEATURE_TOPMEM
unsigned long mapped_rw;
unsigned long mapped_ro;
unsigned long shared_clean;
unsigned long shared_dirty;
unsigned long private_clean;
unsigned long private_dirty;
unsigned long stack;
struct smaprec smaps;
#endif
char state[4];
/* basename of executable in exec(2), read from /proc/N/stat

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@ -137,12 +137,9 @@ static unsigned long fast_strtoul_16(char **endptr)
*endptr = str; /* We skip trailing space! */
return n;
}
/* TOPMEM uses fast_strtoul_10, so... */
# undef ENABLE_FEATURE_FAST_TOP
# define ENABLE_FEATURE_FAST_TOP 1
#endif
#if ENABLE_FEATURE_FAST_TOP
#if ENABLE_FEATURE_FAST_TOP || ENABLE_FEATURE_TOPMEM || ENABLE_PMAP
/* We cut a lot of corners here for speed */
static unsigned long fast_strtoul_10(char **endptr)
{
@ -177,6 +174,111 @@ static char *skip_fields(char *str, int count)
}
#endif
#if ENABLE_FEATURE_TOPMEM || ENABLE_PMAP
int FAST_FUNC procps_read_smaps(pid_t pid, struct smaprec *total,
void (*cb)(struct smaprec *, void *), void *data)
{
FILE *file;
struct smaprec currec;
char filename[sizeof("/proc/%u/smaps") + sizeof(int)*3];
char buf[PROCPS_BUFSIZE];
#if !ENABLE_PMAP
void (*cb)(struct smaprec *, void *) = NULL;
void *data = NULL;
#endif
sprintf(filename, "/proc/%u/smaps", (int)pid);
file = fopen_for_read(filename);
if (!file)
return 1;
memset(&currec, 0, sizeof(currec));
while (fgets(buf, PROCPS_BUFSIZE, file)) {
// Each mapping datum has this form:
// f7d29000-f7d39000 rw-s ADR M:m OFS FILE
// Size: nnn kB
// Rss: nnn kB
// .....
char *tp = buf, *p;
#define SCAN(S, X) \
if (strncmp(tp, S, sizeof(S)-1) == 0) { \
tp = skip_whitespace(tp + sizeof(S)-1); \
total->X += currec.X = fast_strtoul_10(&tp); \
continue; \
}
if (cb) {
SCAN("Pss:" , smap_pss );
SCAN("Swap:" , smap_swap );
}
SCAN("Private_Dirty:", private_dirty);
SCAN("Private_Clean:", private_clean);
SCAN("Shared_Dirty:" , shared_dirty );
SCAN("Shared_Clean:" , shared_clean );
#undef SCAN
tp = strchr(buf, '-');
if (tp) {
// We reached next mapping - the line of this form:
// f7d29000-f7d39000 rw-s ADR M:m OFS FILE
if (cb) {
/* If we have a previous record, there's nothing more
* for it, call the callback and clear currec
*/
if (currec.smap_size)
cb(&currec, data);
free(currec.smap_name);
}
memset(&currec, 0, sizeof(currec));
*tp = ' ';
tp = buf;
currec.smap_start = fast_strtoul_16(&tp);
currec.smap_size = (fast_strtoul_16(&tp) - currec.smap_start) >> 10;
strncpy(currec.smap_mode, tp, sizeof(currec.smap_mode)-1);
// skipping "rw-s ADR M:m OFS "
tp = skip_whitespace(skip_fields(tp, 4));
// filter out /dev/something (something != zero)
if (strncmp(tp, "/dev/", 5) != 0 || strcmp(tp, "/dev/zero\n") == 0) {
if (currec.smap_mode[1] == 'w') {
currec.mapped_rw = currec.smap_size;
total->mapped_rw += currec.smap_size;
} else if (currec.smap_mode[1] == '-') {
currec.mapped_ro = currec.smap_size;
total->mapped_ro += currec.smap_size;
}
}
if (strcmp(tp, "[stack]\n") == 0)
total->stack += currec.smap_size;
if (cb) {
p = skip_non_whitespace(tp);
if (p == tp) {
currec.smap_name = xstrdup(" [ anon ]");
} else {
*p = '\0';
currec.smap_name = xstrdup(tp);
}
}
total->smap_size += currec.smap_size;
}
}
fclose(file);
if (cb) {
if (currec.smap_size)
cb(&currec, data);
free(currec.smap_name);
}
return 0;
}
#endif
void BUG_comm_size(void);
procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags)
{
@ -365,54 +467,8 @@ procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags)
}
#if ENABLE_FEATURE_TOPMEM
if (flags & (PSSCAN_SMAPS)) {
FILE *file;
strcpy(filename_tail, "smaps");
file = fopen_for_read(filename);
if (file) {
while (fgets(buf, sizeof(buf), file)) {
unsigned long sz;
char *tp;
char w;
#define SCAN(str, name) \
if (strncmp(buf, str, sizeof(str)-1) == 0) { \
tp = skip_whitespace(buf + sizeof(str)-1); \
sp->name += fast_strtoul_10(&tp); \
continue; \
}
SCAN("Shared_Clean:" , shared_clean );
SCAN("Shared_Dirty:" , shared_dirty );
SCAN("Private_Clean:", private_clean);
SCAN("Private_Dirty:", private_dirty);
#undef SCAN
// f7d29000-f7d39000 rw-s ADR M:m OFS FILE
tp = strchr(buf, '-');
if (tp) {
*tp = ' ';
tp = buf;
sz = fast_strtoul_16(&tp); /* start */
sz = (fast_strtoul_16(&tp) - sz) >> 10; /* end - start */
// tp -> "rw-s" string
w = tp[1];
// skipping "rw-s ADR M:m OFS "
tp = skip_whitespace(skip_fields(tp, 4));
// filter out /dev/something (something != zero)
if (strncmp(tp, "/dev/", 5) != 0 || strcmp(tp, "/dev/zero\n") == 0) {
if (w == 'w') {
sp->mapped_rw += sz;
} else if (w == '-') {
sp->mapped_ro += sz;
}
}
//else printf("DROPPING %s (%s)\n", buf, tp);
if (strcmp(tp, "[stack]\n") == 0)
sp->stack += sz;
}
}
fclose(file);
}
}
if (flags & PSSCAN_SMAPS)
procps_read_smaps(pid, &sp->smaps, NULL, NULL);
#endif /* TOPMEM */
#if ENABLE_FEATURE_PS_ADDITIONAL_COLUMNS
if (flags & PSSCAN_RUIDGID) {

111
procps/pmap.c Normal file
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@ -0,0 +1,111 @@
/*
* pmap implementation for busybox
*
* Copyright (C) 2010 Nokia Corporation. All rights reserved.
* Written by Alexander Shishkin <virtuoso@slind.org>
*
* Licensed under GPLv2 or later, see the LICENSE file in this source tree
* for details.
*/
//applet:IF_PMAP(APPLET(pmap, _BB_DIR_USR_BIN, _BB_SUID_DROP))
//kbuild:lib-$(CONFIG_PMAP) += pmap.o
//config:config PMAP
//config: bool "pmap"
//config: default y
//config: help
//config: Display processes' memory mappings.
//usage:#define pmap_trivial_usage
//usage: "[-x][-q] PID"
//usage:#define pmap_full_usage "\n\n"
//usage: "Display detailed precesses' memory usage\n"
//usage: "\nOptions:"
//usage: "\n -x show details"
//usage: "\n -q quiet"
#include "libbb.h"
#if ULONG_MAX == 0xffffffff
# define TABS "\t"
# define AFMT "8"
# define DASHES ""
#else
# define TABS "\t\t"
# define AFMT "16"
# define DASHES "--------"
#endif
enum {
OPT_x = 1 << 0,
OPT_q = 1 << 1,
};
static void print_smaprec(struct smaprec *currec, void *data)
{
unsigned opt = (unsigned)data;
printf("%0" AFMT "lx ", currec->smap_start);
if (opt & OPT_x)
printf("%7lu %7lu %7lu %7lu ",
currec->smap_size,
currec->smap_pss,
currec->private_dirty,
currec->smap_swap);
else
printf("%7luK", currec->smap_size);
printf(" %.4s %s\n", currec->smap_mode, currec->smap_name);
}
static int procps_get_maps(pid_t pid, unsigned opt)
{
struct smaprec total;
int ret;
char buf[256];
read_cmdline(buf, sizeof(buf), pid, "no such process");
printf("%u: %s\n", (int)pid, buf);
if (!(opt & OPT_q) && (opt & OPT_x))
puts("Address" TABS " Kbytes PSS Dirty Swap Mode Mapping");
memset(&total, 0, sizeof(total));
ret = procps_read_smaps(pid, &total, print_smaprec, (void*)opt);
if (ret)
return ret;
if (!(opt & OPT_q)) {
if (opt & OPT_x)
printf("--------" DASHES " ------ ------ ------ ------\n"
"total" TABS " %7lu %7lu %7lu %7lu\n",
total.smap_size, total.smap_pss, total.private_dirty, total.smap_swap);
else
printf("mapped: %luK\n", total.smap_size);
}
return 0;
}
int pmap_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int pmap_main(int argc UNUSED_PARAM, char **argv)
{
unsigned opts;
int ret;
opts = getopt32(argv, "xq");
argv += optind;
ret = 0;
while (*argv) {
pid_t pid = xatoi_positive(*argv++);
/* GNU pmap returns 42 if any of the pids failed */
if (procps_get_maps(pid, opts) != 0)
ret = 42;
}
return ret;
}

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@ -942,20 +942,20 @@ int top_main(int argc UNUSED_PARAM, char **argv)
}
#if ENABLE_FEATURE_TOPMEM
else { /* TOPMEM */
if (!(p->mapped_ro | p->mapped_rw))
if (!(p->smaps.mapped_ro | p->smaps.mapped_rw))
continue; /* kernel threads are ignored */
n = ntop;
/* No bug here - top and topmem are the same */
top = xrealloc_vector(topmem, 6, ntop++);
strcpy(topmem[n].comm, p->comm);
topmem[n].pid = p->pid;
topmem[n].vsz = p->mapped_rw + p->mapped_ro;
topmem[n].vszrw = p->mapped_rw;
topmem[n].rss_sh = p->shared_clean + p->shared_dirty;
topmem[n].rss = p->private_clean + p->private_dirty + topmem[n].rss_sh;
topmem[n].dirty = p->private_dirty + p->shared_dirty;
topmem[n].dirty_sh = p->shared_dirty;
topmem[n].stack = p->stack;
topmem[n].vsz = p->smaps.mapped_rw + p->smaps.mapped_ro;
topmem[n].vszrw = p->smaps.mapped_rw;
topmem[n].rss_sh = p->smaps.shared_clean + p->smaps.shared_dirty;
topmem[n].rss = p->smaps.private_clean + p->smaps.private_dirty + topmem[n].rss_sh;
topmem[n].dirty = p->smaps.private_dirty + p->smaps.shared_dirty;
topmem[n].dirty_sh = p->smaps.shared_dirty;
topmem[n].stack = p->smaps.stack;
}
#endif
} /* end of "while we read /proc" */