hwloc-ps: split the code reading proc/thread info to a separate file

Signed-off-by: Brice Goglin <Brice.Goglin@inria.fr>

utils/hwloc/Makefile.am

@@ -1,4 +1,4 @@
-# Copyright © 2009-2018 Inria.  All rights reserved.
+# Copyright © 2009-2019 Inria.  All rights reserved.
 # Copyright © 2009-2012, 2014, 2016 Université Bordeaux
 # Copyright © 2009-2014 Cisco Systems, Inc.  All rights reserved.
 #
@@ -20,7 +20,7 @@ EXTRA_DIST = \
         test-hwloc-distrib.output \
         test-hwloc-info.output
 
-noinst_HEADERS = misc.h
+noinst_HEADERS = misc.h common-ps.h
 
 bin_PROGRAMS = \
         hwloc-annotate \
@@ -57,6 +57,10 @@ hwloc_calc_SOURCES = \
         hwloc-calc.h \
         hwloc-calc.c
 
+hwloc_ps_SOURCES = \
+	hwloc-ps.c \
+	common-ps.c
+
 bin_SCRIPTS = hwloc-compress-dir
 if HWLOC_HAVE_LINUX
 bin_SCRIPTS += hwloc-gather-topology

utils/hwloc/common-ps.c

@@ -0,0 +1,199 @@
+/*
+ * Copyright © 2009-2019 Inria.  All rights reserved.
+ * Copyright © 2009-2012 Université Bordeaux
+ * Copyright © 2009-2011 Cisco Systems, Inc.  All rights reserved.
+ * See COPYING in top-level directory.
+ */
+
+#include <private/autogen/config.h>
+#include <hwloc.h>
+#ifdef HWLOC_LINUX_SYS
+#include <hwloc/linux.h>
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#ifdef HAVE_DIRENT_H
+#include <dirent.h>
+#endif
+#include <fcntl.h>
+
+#include "common-ps.h"
+#include "misc.h"
+
+int hwloc_ps_read_process(hwloc_topology_t topology, hwloc_const_bitmap_t topocpuset,
+			  struct hwloc_ps_process *proc,
+			  unsigned long flags, char *pidcmd)
+{
+#ifdef HAVE_DIRENT_H
+  unsigned i;
+  hwloc_bitmap_t cpuset;
+  unsigned pathlen;
+  char *path;
+  char *end;
+  int fd;
+
+  cpuset = hwloc_bitmap_alloc();
+  if (!cpuset)
+    return -1;
+
+  pathlen = 6 + 21 + 1 + 7 + 1;
+  path = malloc(pathlen);
+  snprintf(path, pathlen, "/proc/%ld/cmdline", proc->pid);
+  fd = open(path, O_RDONLY);
+  free(path);
+
+  if (fd >= 0) {
+    ssize_t n = read(fd, proc->name, sizeof(proc->name) - 1);
+    close(fd);
+
+    if (n <= 0)
+      /* Ignore kernel threads and errors */
+      goto out;
+
+    proc->name[n] = 0;
+  }
+
+  proc->string[0] = '\0';
+  if (pidcmd) {
+    char *cmd;
+    FILE *file;
+    cmd = malloc(strlen(pidcmd)+1+5+2+1);
+    sprintf(cmd, "%s %u", pidcmd, (unsigned) proc->pid);
+    file = popen(cmd, "r");
+    if (file) {
+      if (fgets(proc->string, sizeof(proc->string), file)) {
+	end = strchr(proc->string, '\n');
+	if (end)
+	  *end = '\0';
+      }
+      pclose(file);
+    }
+    free(cmd);
+  }
+
+  if (flags & HWLOC_PS_FLAG_THREADS) {
+#ifdef HWLOC_LINUX_SYS
+    /* check if some threads must be displayed */
+    DIR *taskdir;
+
+    pathlen = 6 + 21 + 1 + 4 + 1;
+    path = malloc(pathlen);
+    snprintf(path, pathlen, "/proc/%ld/task", proc->pid);
+    taskdir = opendir(path);
+    if (taskdir) {
+      struct dirent *taskdirent;
+      long tid;
+      unsigned n = 0;
+      /* count threads */
+      while ((taskdirent = readdir(taskdir))) {
+	tid = strtol(taskdirent->d_name, &end, 10);
+	if (*end)
+	  /* Not a number */
+	  continue;
+	n++;
+      }
+      if (n > 1) {
+	/* if there's more than one thread, see if some are bound */
+	proc->threads = calloc(n, sizeof(*proc->threads));
+	if (proc->threads) {
+	  /* reread the directory but gather info now */
+	  rewinddir(taskdir);
+	  i = 0;
+	  while ((taskdirent = readdir(taskdir))) {
+	    char *path2;
+	    unsigned path2len;
+
+	    tid = strtol(taskdirent->d_name, &end, 10);
+	    if (*end)
+	      /* Not a number */
+	      continue;
+
+	    proc->threads[i].tid = tid;
+
+	    path2len = pathlen + 1 + 21 + 1 + 4 + 1;
+	    path2 = malloc(path2len);
+	    if (path2) {
+	      int commfd;
+	      snprintf(path2, path2len, "%s/%ld/comm", path, tid);
+	      commfd = open(path2, O_RDWR);
+	      if (commfd >= 0) {
+		read(commfd, proc->threads[i].name, sizeof(proc->threads[i].name));
+		close(commfd);
+		proc->threads[i].name[sizeof(proc->threads[i].name)-1] = '\0';
+		end = strchr(proc->threads[i].name, '\n');
+		if (end)
+		  *end = '\0';
+	      }
+	      free(path2);
+	    }
+
+	    if (flags & HWLOC_PS_FLAG_LASTCPULOCATION) {
+	      if (hwloc_linux_get_tid_last_cpu_location(topology, tid, cpuset))
+		goto next;
+	    } else {
+	      if (hwloc_linux_get_tid_cpubind(topology, tid, cpuset))
+		goto next;
+	    }
+	    hwloc_bitmap_and(cpuset, cpuset, topocpuset);
+	    if (hwloc_bitmap_iszero(cpuset))
+	      goto next;
+
+	    proc->threads[i].cpuset = hwloc_bitmap_dup(cpuset);
+	    if (!hwloc_bitmap_isequal(cpuset, topocpuset)) {
+	      proc->threads[i].bound = 1;
+	      proc->nboundthreads++;
+	    }
+
+	  next:
+	    i++;
+	    proc->nthreads++;
+	    if (i == n)
+	      /* ignore the lastly created threads, I'm too lazy to reallocate */
+	      break;
+	  }
+	} else {
+	  /* failed to alloc, behave as if there were no threads */
+	}
+      }
+      closedir(taskdir);
+    }
+    free(path);
+#endif /* HWLOC_LINUX_SYS */
+  }
+
+  if (flags & HWLOC_PS_FLAG_LASTCPULOCATION) {
+    if (hwloc_get_proc_last_cpu_location(topology, proc->pid, cpuset, 0))
+      goto out;
+  } else {
+    if (hwloc_get_proc_cpubind(topology, proc->pid, cpuset, 0))
+      goto out;
+  }
+
+  hwloc_bitmap_and(cpuset, cpuset, topocpuset);
+  if (hwloc_bitmap_iszero(cpuset))
+    goto out;
+
+  proc->bound = !hwloc_bitmap_isequal(cpuset, topocpuset);
+  proc->cpuset = cpuset;
+  return 0;
+
+ out:
+  hwloc_bitmap_free(cpuset);
+#endif /* HAVE_DIRENT_H */
+  return -1;
+}
+
+void hwloc_ps_free_process(struct hwloc_ps_process *proc)
+{
+  unsigned i;
+
+  if (proc->nthreads)
+    for(i=0; i<proc->nthreads; i++)
+      if (proc->threads[i].cpuset)
+	hwloc_bitmap_free(proc->threads[i].cpuset);
+  free(proc->threads);
+
+  hwloc_bitmap_free(proc->cpuset);
+}

utils/hwloc/common-ps.h

@@ -0,0 +1,41 @@
+/*
+ * Copyright © 2009-2019 Inria.  All rights reserved.
+ * Copyright © 2009-2012 Université Bordeaux
+ * Copyright © 2009-2011 Cisco Systems, Inc.  All rights reserved.
+ * See COPYING in top-level directory.
+ */
+
+#ifndef UTILS_HWLOC_PS_H
+#define UTILS_HWLOC_PS_H
+
+#include <private/autogen/config.h>
+#include <hwloc.h>
+
+#define HWLOC_PS_TIDNAME_MAX 16 /* specified in pthread_setname_np.3 */
+
+struct hwloc_ps_process {
+  long pid;
+  char string[1024];
+  char name[64];
+  hwloc_bitmap_t cpuset;
+  int bound;
+  unsigned nthreads;
+  unsigned nboundthreads;
+  struct hwloc_ps_thread {
+    long tid;
+    hwloc_bitmap_t cpuset;
+    int bound;
+    char name[HWLOC_PS_TIDNAME_MAX];
+  } *threads;
+};
+
+#define HWLOC_PS_FLAG_THREADS (1UL<<0)
+#define HWLOC_PS_FLAG_LASTCPULOCATION (1UL<<1)
+
+int hwloc_ps_read_process(hwloc_topology_t topology, hwloc_const_bitmap_t topocpuset,
+			  struct hwloc_ps_process *proc,
+			  unsigned long flags, char *pidcmd);
+
+void hwloc_ps_free_process(struct hwloc_ps_process *proc);
+
+#endif /* UTILS_HWLOC_PS_H */