1 files changed, 48 insertions, 82 deletions

diff --git a/libbb/procps.c b/libbb/procps.c
index 2cdfce42a..3256fafc5 100644
--- a/libbb/procps.c
+++ b/libbb/procps.c
@@ -109,7 +109,7 @@ void FAST_FUNC free_procps_scan(procps_status_t* sp)
 }
 
 #if ENABLE_FEATURE_TOPMEM || ENABLE_PMAP
-static unsigned long long fast_strtoull_16(char **endptr)
+unsigned long long FAST_FUNC fast_strtoull_16(char **endptr)
 {
         unsigned char c;
         char *str = *endptr;
@@ -130,7 +130,7 @@ static unsigned long long fast_strtoull_16(char **endptr)
 
 #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)
+unsigned long FAST_FUNC fast_strtoul_10(char **endptr)
 {
         unsigned char c;
         char *str = *endptr;
@@ -159,7 +159,7 @@ static unsigned long long fast_strtoull_10(char **endptr)
         return n;
 }
 # else
-# define fast_strtoull_10(endptr) fast_strtoul_10(endptr)
+#  define fast_strtoull_10(endptr) fast_strtoul_10(endptr)
 # endif
 
 # if ENABLE_FEATURE_FAST_TOP
@@ -173,7 +173,7 @@ static long fast_strtol_10(char **endptr)
 }
 # endif
 
-static char *skip_fields(char *str, int count)
+char* FAST_FUNC skip_fields(char *str, int count)
 {
         do {
                 while (*str++ != ' ')
@@ -184,35 +184,25 @@ static char *skip_fields(char *str, int count)
 }
 #endif
 
-#if ENABLE_FEATURE_TOPMEM || ENABLE_PMAP
-static char* skip_whitespace_if_prefixed_with(char *buf, const char *prefix)
+#if ENABLE_FEATURE_TOPMEM
+static NOINLINE void procps_read_smaps(pid_t pid, procps_status_t *sp)
 {
-        char *tp = is_prefixed_with(buf, prefix);
-        if (tp) {
-                tp = skip_whitespace(tp);
-        }
-        return tp;
-}
+        // There is A LOT of /proc/PID/smaps data on a big system.
+        // Optimize this for speed, makes "top -m" faster.
+//TODO large speedup:
+//read /proc/PID/smaps_rollup (cumulative stats of all mappings, much faster)
+//and  /proc/PID/maps         to get mapped_ro and mapped_rw (IOW: VSZ,VSZRW)
 
-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;
+                return;
 
-        memset(&currec, 0, sizeof(currec));
         while (fgets(buf, PROCPS_BUFSIZE, file)) {
                 // Each mapping datum has this form:
                 // f7d29000-f7d39000 rw-s FILEOFS M:m INODE FILENAME
@@ -220,80 +210,53 @@ int FAST_FUNC procps_read_smaps(pid_t pid, struct smaprec *total,
                 // Rss:                 nnn kB
                 // .....
 
-                char *tp, *p;
+                char *tp;
 
+                if (buf[0] == 'S' || buf[0] == 'P') {
 #define SCAN(S, X) \
-                if ((tp = skip_whitespace_if_prefixed_with(buf, S)) != NULL) { \
-                        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 );
+                        if (memcmp(buf, S, sizeof(S)-1) == 0) { \
+                                tp = skip_whitespace(buf + sizeof(S)-1); \
+                                sp->X += fast_strtoul_10(&tp); \
+                                continue; \
+                        }
+                        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 FILEOFS M:m INODE FILENAME
 
-                        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));
+                        char *rwx;
+                        unsigned long sz;
 
                         *tp = ' ';
                         tp = buf;
-                        currec.smap_start = fast_strtoull_16(&tp);
-                        currec.smap_size = (fast_strtoull_16(&tp) - currec.smap_start) >> 10;
-
-                        strncpy(currec.smap_mode, tp, sizeof(currec.smap_mode)-1);
-
+                        sz = fast_strtoull_16(&tp); // start
+                        sz = (fast_strtoull_16(&tp) - sz) >> 10; // end - start
+                        // tp -> "rw-s" string
+                        rwx = tp;
                         // skipping "rw-s FILEOFS M:m INODE "
                         tp = skip_whitespace(skip_fields(tp, 4));
-                        // filter out /dev/something (something != zero)
-                        if (!is_prefixed_with(tp, "/dev/") || 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 not a device memory mapped...
+                        if (memcmp(tp, "/dev/", 5) != 0    // not "/dev/something"
+                         || strcmp(tp + 5, "zero\n") == 0  // or is "/dev/zero" (which isn't a device)
+                        ) {
+                                if (rwx[1] == 'w')
+                                        sp->mapped_rw += sz;
+                                else if (rwx[0] == 'r' || rwx[2] == 'x')
+                                        sp->mapped_ro += sz;
+                                // else: seen "---p" mappings (mmap guard gaps?),
+                                // do NOT account these as VSZ, they aren't really
                         }
-
                         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;
+                                sp->stack += sz;
                 }
         }
         fclose(file);
-
-        if (cb) {
-                if (currec.smap_size)
-                        cb(&currec, data);
-                free(currec.smap_name);
-        }
-
-        return 0;
 }
 #endif
 
@@ -502,7 +465,7 @@ procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags)
 
 #if ENABLE_FEATURE_TOPMEM
                 if (flags & PSSCAN_SMAPS)
-                        procps_read_smaps(pid, &sp->smaps, NULL, NULL);
+                        procps_read_smaps(pid, sp);
 #endif /* TOPMEM */
 #if ENABLE_FEATURE_PS_ADDITIONAL_COLUMNS
                 if (flags & PSSCAN_RUIDGID) {
@@ -585,13 +548,15 @@ procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags)
         return sp;
 }
 
-void FAST_FUNC read_cmdline(char *buf, int col, unsigned pid, const char *comm)
+int FAST_FUNC read_cmdline(char *buf, int col, unsigned pid, const char *comm)
 {
         int sz;
         char filename[sizeof("/proc/%u/cmdline") + sizeof(int)*3];
 
         sprintf(filename, "/proc/%u/cmdline", pid);
         sz = open_read_close(filename, buf, col - 1);
+        if (sz < 0)
+                return sz;
         if (sz > 0) {
                 const char *base;
                 int comm_len;
@@ -614,7 +579,7 @@ void FAST_FUNC read_cmdline(char *buf, int col, unsigned pid, const char *comm)
                  * It allows to see thread names set by prctl(PR_SET_NAME).
                  */
                 if (!comm)
-                        return;
+                        return 0;
                 comm_len = strlen(comm);
                 /* Why compare up to comm_len, not COMM_LEN-1?
                  * Well, some processes rewrite argv, and use _spaces_ there
@@ -628,13 +593,14 @@ void FAST_FUNC read_cmdline(char *buf, int col, unsigned pid, const char *comm)
                                 memmove(buf + comm_len, buf, col - comm_len);
                         snprintf(buf, col, "{%s}", comm);
                         if (col <= comm_len)
-                                return;
+                                return 0;
                         buf[comm_len - 1] = ' ';
                         buf[col - 1] = '\0';
                 }
         } else {
                 snprintf(buf, col, "[%s]", comm ? comm : "?");
         }
+        return 0;
 }
 
 /* from kernel: