[patch] patch to fix memory usage in nscd

nscd_memory_fix.patch (text/plain), 20.10 KB, created by Ian Milligan on 2009-06-02 21:33:18 UTC

diff --git libc/nscd/aicache.c libc/nscd/aicache.c
index a69a778..2518f80 100644
--- libc/nscd/aicache.c
+++ libc/nscd/aicache.c
@@ -1,5 +1,5 @@
 /* Cache handling for host lookup.
-   Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
+   Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <[e-mail]>, 2004.
 
@@ -262,7 +262,8 @@ addhstaiX (struct database_dyn *db, int fd, request_header *req,
 		{
 		  dataset = (struct dataset *) mempool_alloc (db,
 							      total
-							      + req->key_len);
+							      + req->key_len,
+							      IDX_result_data);
 		  if (dataset == NULL)
 		    ++db->head->addfailed;
 		}
@@ -338,7 +339,8 @@ addhstaiX (struct database_dyn *db, int fd, request_header *req,
 		      struct dataset *newp
 			= (struct dataset *) mempool_alloc (db,
 							    total
-							    + req->key_len);
+							    + req->key_len,
+							    IDX_result_data);
 		      if (__builtin_expect (newp != NULL, 1))
 			{
 			  /* Adjust pointer into the memory block.  */
@@ -424,7 +426,8 @@ addhstaiX (struct database_dyn *db, int fd, request_header *req,
       if (fd != -1)
 	TEMP_FAILURE_RETRY (send (fd, &notfound, total, MSG_NOSIGNAL));
 
-      dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len);
+      dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len,
+			       IDX_result_data);
       /* If we cannot permanently store the result, so be it.  */
       if (dataset != NULL)
 	{
diff --git libc/nscd/cache.c libc/nscd/cache.c
index 12c4f01..b1dc2c5 100644
--- libc/nscd/cache.c
+++ libc/nscd/cache.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 1998, 1999, 2003-2006, 2007 Free Software Foundation, Inc.
+/* Copyright (c) 1998, 1999, 2003-2007, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <[e-mail]>, 1998.
 
@@ -155,11 +155,16 @@ cache_add (int type, const void *key, size_t len, struct datahead *packet,
   unsigned long int hash = __nis_hash (key, len) % table->head->module;
   struct hashentry *newp;
 
-  newp = mempool_alloc (table, sizeof (struct hashentry));
+  newp = mempool_alloc (table, sizeof (struct hashentry), IDX_record_data);
   /* If we cannot allocate memory, just do not do anything.  */
   if (newp == NULL)
     {
       ++table->head->addfailed;
+
+      /* Mark the in-flight memory as unused.  */
+      for (enum in_flight idx = 0; idx < IDX_record_data; ++idx)
+	mem_in_flight.block[idx].dbidx = -1;
+
       return -1;
     }
 
@@ -215,6 +220,10 @@ cache_add (int type, const void *key, size_t len, struct datahead *packet,
     else
       next_wakeup = table->wakeup_time;
 
+  /* Mark the in-flight memory as unused.  */
+  for (enum in_flight idx = 0; idx < IDX_last; ++idx)
+    mem_in_flight.block[idx].dbidx = -1;
+
   return 0;
 }
 
diff --git libc/nscd/connections.c libc/nscd/connections.c
index 5da5e5f..64c82cb 100644
--- libc/nscd/connections.c
+++ libc/nscd/connections.c
@@ -225,6 +225,11 @@ static int sock;
 /* Number of times clients had to wait.  */
 unsigned long int client_queued;
 
+/* Data structure for recording in-flight memory allocation.  */
+__thread struct mem_in_flight mem_in_flight;
+/* Global list of the mem_in_flight variables of all the threads.  */
+struct mem_in_flight *mem_in_flight_list;
+
 
 ssize_t
 writeall (int fd, const void *buf, size_t len)
@@ -964,7 +969,7 @@ send_ro_fd (struct database_dyn *db, char *key, int fd)
 
 /* Handle new request.  */
 static void
-handle_request (int fd, request_header *req, void *key, uid_t uid)
+handle_request (int fd, request_header *req, void *key, uid_t uid, pid_t pid)
 {
   if (__builtin_expect (req->version, NSCD_VERSION) != NSCD_VERSION)
     {
@@ -979,7 +984,31 @@ cannot handle old request version %d; current version is %d"),
   if (selinux_enabled && nscd_request_avc_has_perm (fd, req->type) != 0)
     {
       if (debug_level > 0)
-	dbg_log (_("request not handled due to missing permission"));
+	{
+#ifdef SO_PEERCRED
+# ifdef PATH_MAX
+	  char buf[PATH_MAX];
+# else
+	  char buf[4096];
+# endif
+
+	  snprintf (buf, sizeof (buf), "/proc/%ld/exe", (long int) pid);
+	  ssize_t n = readlink (buf, buf, sizeof (buf) - 1);
+
+	  if (n <= 0)
+	    dbg_log (_("\
+request from %ld not handled due to missing permission"), (long int) pid);
+	  else
+	    {
+	      buf[n] = '\0';
+	      dbg_log (_("\
+request from '%s' [%ld] not handled due to missing permission"),
+		       buf, (long int) pid);
+	    }
+#else
+	  dbg_log (_("request not handled due to missing permission"));
+#endif
+	}
       return;
     }
 
@@ -1426,6 +1455,16 @@ nscd_run_worker (void *p)
 {
   char buf[256];
 
+  /* Initialize the memory-in-flight list.  */
+  for (enum in_flight idx = 0; idx < IDX_last; ++idx)
+    mem_in_flight.block[idx].dbidx = -1;
+  /* And queue this threads structure.  */
+  do
+    mem_in_flight.next = mem_in_flight_list;
+  while (atomic_compare_and_exchange_bool_acq (&mem_in_flight_list,
+					       &mem_in_flight,
+					       mem_in_flight.next) != 0);
+
   /* Initial locking.  */
   pthread_mutex_lock (&readylist_lock);
 
@@ -1491,6 +1530,8 @@ nscd_run_worker (void *p)
 	  if (getsockopt (fd, SOL_SOCKET, SO_PEERCRED, &caller, &optlen) == 0)
 	    pid = caller.pid;
 	}
+#else
+      const pid_t pid = 0;
 #endif
 
       /* It should not be possible to crash the nscd with a silly
@@ -1531,7 +1572,7 @@ handle_request: request received (Version = %d)"), req.version);
 	    }
 
 	  /* Phew, we got all the data, now process it.  */
-	  handle_request (fd, &req, keybuf, uid);
+	  handle_request (fd, &req, keybuf, uid, pid);
 	}
 
     close_and_out:
diff --git libc/nscd/grpcache.c libc/nscd/grpcache.c
index 002f04f..dbc406f 100644
--- libc/nscd/grpcache.c
+++ libc/nscd/grpcache.c
@@ -1,5 +1,5 @@
 /* Cache handling for group lookup.
-   Copyright (C) 1998-2005, 2006, 2007 Free Software Foundation, Inc.
+   Copyright (C) 1998-2005, 2006, 2007, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <[e-mail]>, 1998.
 
@@ -113,7 +113,8 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req,
 	  written = TEMP_FAILURE_RETRY (send (fd, &notfound, total,
 					      MSG_NOSIGNAL));
 
-	  dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len);
+	  dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len,
+				   IDX_result_data);
 	  /* If we cannot permanently store the result, so be it.  */
 	  if (dataset != NULL)
 	    {
@@ -204,7 +205,8 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req,
 
       if (he == NULL)
 	{
-	  dataset = (struct dataset *) mempool_alloc (db, total + n);
+	  dataset = (struct dataset *) mempool_alloc (db, total + n,
+						      IDX_result_data);
 	  if (dataset == NULL)
 	    ++db->head->addfailed;
 	}
@@ -274,7 +276,8 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req,
 	      /* We have to create a new record.  Just allocate
 		 appropriate memory and copy it.  */
 	      struct dataset *newp
-		= (struct dataset *) mempool_alloc (db, total + n);
+		= (struct dataset *) mempool_alloc (db, total + n,
+						    IDX_result_data);
 	      if (newp != NULL)
 		{
 		  /* Adjust pointers into the memory block.  */
diff --git libc/nscd/hstcache.c libc/nscd/hstcache.c
index cc04158..b93d418 100644
--- libc/nscd/hstcache.c
+++ libc/nscd/hstcache.c
@@ -1,5 +1,5 @@
 /* Cache handling for host lookup.
-   Copyright (C) 1998-2005, 2006, 2007 Free Software Foundation, Inc.
+   Copyright (C) 1998-2005, 2006, 2007, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <[e-mail]>, 1998.
 
@@ -121,7 +121,8 @@ cache_addhst (struct database_dyn *db, int fd, request_header *req,
 	    written = TEMP_FAILURE_RETRY (send (fd, &notfound, total,
 						MSG_NOSIGNAL));
 
-	  dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len);
+	  dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len,
+				   IDX_result_data);
 	  /* If we cannot permanently store the result, so be it.  */
 	  if (dataset != NULL)
 	    {
@@ -226,7 +227,8 @@ cache_addhst (struct database_dyn *db, int fd, request_header *req,
       if (he == NULL && h_addr_list_cnt == 1)
 	{
 	  dataset = (struct dataset *) mempool_alloc (db,
-						      total + req->key_len);
+						      total + req->key_len,
+						      IDX_result_data);
 	  if (dataset == NULL)
 	    ++db->head->addfailed;
 	}
@@ -312,7 +314,8 @@ cache_addhst (struct database_dyn *db, int fd, request_header *req,
 		     appropriate memory and copy it.  */
 		  struct dataset *newp
 		    = (struct dataset *) mempool_alloc (db,
-							total + req->key_len);
+							total + req->key_len,
+							IDX_result_data);
 		  if (newp != NULL)
 		    {
 		      /* Adjust pointers into the memory block.  */
diff --git libc/nscd/initgrcache.c libc/nscd/initgrcache.c
index 157cd78..4d6513b 100644
--- libc/nscd/initgrcache.c
+++ libc/nscd/initgrcache.c
@@ -1,5 +1,5 @@
 /* Cache handling for host lookup.
-   Copyright (C) 2004, 2005, 2006 Free Software Foundation, Inc.
+   Copyright (C) 2004, 2005, 2006, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <[e-mail]>, 2004.
 
@@ -197,7 +197,8 @@ addinitgroupsX (struct database_dyn *db, int fd, request_header *req,
 	    written = TEMP_FAILURE_RETRY (send (fd, &notfound, total,
 						MSG_NOSIGNAL));
 
-	  dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len);
+	  dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len,
+				   IDX_result_data);
 	  /* If we cannot permanently store the result, so be it.  */
 	  if (dataset != NULL)
 	    {
@@ -259,7 +260,8 @@ addinitgroupsX (struct database_dyn *db, int fd, request_header *req,
       if (he == NULL)
 	{
 	  dataset = (struct dataset *) mempool_alloc (db,
-						      total + req->key_len);
+						      total + req->key_len,
+						      IDX_result_data);
 	  if (dataset == NULL)
 	    ++db->head->addfailed;
 	}
@@ -329,7 +331,8 @@ addinitgroupsX (struct database_dyn *db, int fd, request_header *req,
 	      /* We have to create a new record.  Just allocate
 		 appropriate memory and copy it.  */
 	      struct dataset *newp
-		= (struct dataset *) mempool_alloc (db, total + req->key_len);
+		= (struct dataset *) mempool_alloc (db, total + req->key_len,
+						    IDX_result_data);
 	      if (newp != NULL)
 		{
 		  /* Adjust pointer into the memory block.  */
diff --git libc/nscd/mem.c libc/nscd/mem.c
index 048e3dd..e821729 100644
--- libc/nscd/mem.c
+++ libc/nscd/mem.c
@@ -1,5 +1,5 @@
 /* Cache memory handling.
-   Copyright (C) 2004, 2005, 2006 Free Software Foundation, Inc.
+   Copyright (C) 2004, 2005, 2006, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <[e-mail]>, 2004.
 
@@ -24,6 +24,7 @@
 #include <inttypes.h>
 #include <libintl.h>
 #include <limits.h>
+#include <obstack.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
@@ -79,6 +80,7 @@ static void
 markrange (BITMAP_T *mark, ref_t start, size_t len)
 {
   /* Adjust parameters for block alignment.  */
+  assert ((start & BLOCK_ALIGN_M1) == 0);
   start /= BLOCK_ALIGN;
   len = (len + BLOCK_ALIGN_M1) / BLOCK_ALIGN;
 
@@ -93,7 +95,7 @@ markrange (BITMAP_T *mark, ref_t start, size_t len)
 	  return;
 	}
 
-      mark[elem++] |= 0xff << (start % BITS);
+      mark[elem++] |= ALLBITS << (start % BITS);
       len -= BITS - (start % BITS);
     }
 
@@ -130,14 +132,14 @@ gc (struct database_dyn *db)
   size_t stack_used = sizeof (bool) * db->head->module;
   if (__builtin_expect (stack_used > MAX_STACK_USE, 0))
     stack_used = 0;
-  size_t memory_needed = ((db->head->first_free / BLOCK_ALIGN + BITS - 1)
-			  / BITS) * sizeof (BITMAP_T);
-  if (memory_needed <= MAX_STACK_USE)
+  size_t nmark = (db->head->first_free / BLOCK_ALIGN + BITS - 1) / BITS;
+  size_t memory_needed = nmark * sizeof (BITMAP_T);
+  if (stack_used + memory_needed <= MAX_STACK_USE)
     {
       mark = (BITMAP_T *) alloca (memory_needed);
       mark_use_malloc = false;
       memset (mark, '\0', memory_needed);
-      stack_used = memory_needed;
+      stack_used += memory_needed;
     }
   else
     {
@@ -156,6 +158,7 @@ gc (struct database_dyn *db)
       he = alloca (db->head->nentries * sizeof (struct hashentry *));
       he_data = alloca (db->head->nentries * sizeof (struct hashentry *));
       he_use_malloc = false;
+      stack_used += memory_needed;
     }
   else
     {
@@ -197,6 +200,32 @@ gc (struct database_dyn *db)
     }
   assert (cnt == db->head->nentries);
 
+  /* Go through the list of in-flight memory blocks.  */
+  struct mem_in_flight *mrunp = mem_in_flight_list;
+  while (mrunp != NULL)
+    {
+      /* NB: There can be no race between this test and another thread
+        setting the field to the index we are looking for because
+        this would require the other thread to also have the memlock
+        for the database.
+
+	NB2: we do not have to look at latter blocks (higher indices) if
+	earlier blocks are not in flight.  They are always allocated in
+	sequence.  */
+      for (enum in_flight idx = IDX_result_data;
+	   idx < IDX_last && mrunp->block[idx].dbidx == db - dbs; ++idx)
+	{
+	  assert (mrunp->block[idx].blockoff >= 0);
+	  assert (mrunp->block[idx].blocklen < db->memsize);
+	  assert (mrunp->block[idx].blockoff
+		  + mrunp->block[0].blocklen <= db->memsize);
+	  markrange (mark, mrunp->block[idx].blockoff,
+		     mrunp->block[idx].blocklen);
+	}
+
+      mrunp = mrunp->next;
+    }
+
   /* Sort the entries by the addresses of the referenced data.  All
      the entries pointing to the same DATAHEAD object will have the
      same key.  Stability of the sorting is unimportant.  */
@@ -206,8 +235,13 @@ gc (struct database_dyn *db)
   /* Sort the entries by their address.  */
   qsort (he, cnt, sizeof (struct hashentry *), sort_he);
 
+#define obstack_chunk_alloc xmalloc
+#define obstack_chunk_free free
+  struct obstack ob;
+  obstack_init (&ob);
+
   /* Determine the highest used address.  */
-  size_t high = sizeof (mark);
+  size_t high = nmark;
   while (high > 0 && mark[high - 1] == 0)
     --high;
 
@@ -338,8 +372,14 @@ gc (struct database_dyn *db)
 	 displacement.  */
       ref_t disp = off_alloc - off_free;
 
-      struct moveinfo *new_move
-	= (struct moveinfo *) alloca (sizeof (*new_move));
+      struct moveinfo *new_move;
+      if (stack_used + sizeof (*new_move) <= MAX_STACK_USE)
+	{
+	  new_move = alloca (sizeof (*new_move));
+	  stack_used += sizeof (*new_move);
+	}
+      else
+	new_move = obstack_alloc (&ob, sizeof (*new_move));
       new_move->from = db->data + off_alloc;
       new_move->to = db->data + off_free;
       new_move->size = off_allocend - off_alloc;
@@ -499,11 +539,13 @@ gc (struct database_dyn *db)
     free (he);
   if (mark_use_malloc)
     free (mark);
+
+  obstack_free (&ob, NULL);
 }
 
 
 void *
-mempool_alloc (struct database_dyn *db, size_t len)
+mempool_alloc (struct database_dyn *db, size_t len, enum in_flight idx)
 {
   /* Make sure LEN is a multiple of our maximum alignment so we can
      keep track of used memory is multiples of this alignment value.  */
@@ -564,9 +606,16 @@ mempool_alloc (struct database_dyn *db, size_t len)
     }
   else
     {
+      /* Remember that we have allocated this memory.  */
+      assert (idx >= 0 && idx < IDX_last);
+      mem_in_flight.block[idx].dbidx = db - dbs;
+      mem_in_flight.block[idx].blocklen = len;
+      mem_in_flight.block[idx].blockoff = db->head->first_free;
+
       db->head->first_free += len;
 
       db->last_alloc_failed = false;
+
     }
 
   pthread_mutex_unlock (&db->memlock);
diff --git libc/nscd/nscd.h libc/nscd/nscd.h
index ec2d945..60cad28 100644
--- libc/nscd/nscd.h
+++ libc/nscd/nscd.h
@@ -181,6 +181,31 @@ extern uid_t old_uid;
 extern gid_t old_gid;
 
 
+/* Memory allocation in flight.  Each thread can have a limited number
+   of allocation in flight.  No need to create dynamic data
+   structures.  We use fixed indices.  */
+enum in_flight
+  {
+    IDX_result_data = 0,
+    /* Keep the IDX_record_data entry last at all times.  */
+    IDX_record_data = 1,
+    IDX_last
+  };
+extern __thread struct mem_in_flight
+{
+  struct
+  {
+    int dbidx;
+    nscd_ssize_t blocklen;
+    nscd_ssize_t blockoff;
+  } block[IDX_last];
+
+  struct mem_in_flight *next;
+} mem_in_flight;
+/* Global list of the mem_in_flight variables of all the threads.  */
+extern struct mem_in_flight *mem_in_flight_list;
+
+
 /* Prototypes for global functions.  */
 
 /* nscd.c */
@@ -271,7 +296,8 @@ extern void readdservbyport (struct database_dyn *db, struct hashentry *he,
 			     struct datahead *dh);
 
 /* mem.c */
-extern void *mempool_alloc (struct database_dyn *db, size_t len);
+extern void *mempool_alloc (struct database_dyn *db, size_t len,
+			    enum in_flight idx);
 extern void gc (struct database_dyn *db);
 
 
diff --git libc/nscd/pwdcache.c libc/nscd/pwdcache.c
index bc1b6ba..e1bf6e9 100644
--- libc/nscd/pwdcache.c
+++ libc/nscd/pwdcache.c
@@ -1,5 +1,5 @@
 /* Cache handling for passwd lookup.
-   Copyright (C) 1998-2005, 2006, 2007 Free Software Foundation, Inc.
+   Copyright (C) 1998-2005, 2006, 2007, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <[e-mail]>, 1998.
 
@@ -120,7 +120,8 @@ cache_addpw (struct database_dyn *db, int fd, request_header *req,
 	    written = TEMP_FAILURE_RETRY (send (fd, &notfound, total,
 						MSG_NOSIGNAL));
 
-	  dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len);
+	  dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len,
+				   IDX_result_data);
 	  /* If we cannot permanently store the result, so be it.  */
 	  if (dataset != NULL)
 	    {
@@ -199,7 +200,8 @@ cache_addpw (struct database_dyn *db, int fd, request_header *req,
 
       if (he == NULL)
 	{
-	  dataset = (struct dataset *) mempool_alloc (db, total + n);
+	  dataset = (struct dataset *) mempool_alloc (db, total + n,
+						      IDX_result_data);
 	  if (dataset == NULL)
 	    ++db->head->addfailed;
 	}
@@ -270,7 +272,8 @@ cache_addpw (struct database_dyn *db, int fd, request_header *req,
 	      /* We have to create a new record.  Just allocate
 		 appropriate memory and copy it.  */
 	      struct dataset *newp
-		= (struct dataset *) mempool_alloc (db, total + n);
+		= (struct dataset *) mempool_alloc (db, total + n,
+						    IDX_result_data);
 	      if (newp != NULL)
 		{
 		  /* Adjust pointer into the memory block.  */
diff --git libc/nscd/servicescache.c libc/nscd/servicescache.c
index e122cb3..164b6e2 100644
--- libc/nscd/servicescache.c
+++ libc/nscd/servicescache.c
@@ -1,5 +1,5 @@
 /* Cache handling for services lookup.
-   Copyright (C) 2007 Free Software Foundation, Inc.
+   Copyright (C) 2007, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <[e-mail]>, 2007.
 
@@ -103,7 +103,8 @@ cache_addserv (struct database_dyn *db, int fd, request_header *req,
 	  written = TEMP_FAILURE_RETRY (send (fd, &notfound, total,
 					      MSG_NOSIGNAL));
 
-	  dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len);
+	  dataset = mempool_alloc (db, sizeof (struct dataset) + req->key_len,
+				   IDX_result_data);
 	  /* If we cannot permanently store the result, so be it.  */
 	  if (dataset != NULL)
 	    {
@@ -190,7 +191,8 @@ cache_addserv (struct database_dyn *db, int fd, request_header *req,
       if (he == NULL)
 	{
 	  dataset = (struct dataset *) mempool_alloc (db,
-						      total + req->key_len);
+						      total + req->key_len,
+						      IDX_result_data);
 	  if (dataset == NULL)
 	    ++db->head->addfailed;
 	}
@@ -261,7 +263,8 @@ cache_addserv (struct database_dyn *db, int fd, request_header *req,
 	      /* We have to create a new record.  Just allocate
 		 appropriate memory and copy it.  */
 	      struct dataset *newp
-		= (struct dataset *) mempool_alloc (db, total + req->key_len);
+		= (struct dataset *) mempool_alloc (db, total + req->key_len,
+						    IDX_result_data);
 	      if (newp != NULL)
 		{
 		  /* Adjust pointers into the memory block.  */