check_scheduling_in_atomic.c

   1 /*
   2  * Copyright (C) 2018 Oracle.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
  16  */
  17
  18 #include "smatch.h"
  19
  20 static int my_id;
  21
  22 static bool is_strange_GFP_function(struct expression *expr)
  23 {
  24         char *name;
  25         bool ret = false;
  26
  27         if (!expr || expr->type != EXPR_CALL)
  28                 return false;
  29
  30         name = expr_to_str(expr->fn);
  31         if (!name)
  32                 return false;
  33
  34         if (strncmp(name, "__xa_", 5) == 0 ||
  35             strncmp(name, "xa_", 3) == 0 ||
  36             strcmp(name, "ttm_bo_swapout") == 0 ||
  37             strcmp(name, "mas_store_gfp") == 0)
  38                 ret = true;
  39
  40         free_string(name);
  41         return ret;
  42 }
  43
  44 static int warn_line;
  45 static void schedule(struct expression *expr)
  46 {
  47         if (is_impossible_path())
  48                 return;
  49         if (get_preempt_cnt() <= 0)
  50                 return;
  51
  52         if (is_strange_GFP_function(expr))
  53                 return;
  54
  55         if (warn_line == get_lineno())
  56                 return;
  57         warn_line = get_lineno();
  58
  59         sm_msg("warn: sleeping in atomic context");
  60 }
  61
  62 void check_scheduling_in_atomic(int id)
  63 {
  64         my_id = id;
  65
  66         if (option_project != PROJ_KERNEL)
  67                 return;
  68
  69         add_sleep_callback(&schedule);
  70 }
  71