From 23b7dbfaf1e9860f77b6bf1aa3da8610bf31b03c Mon Sep 17 00:00:00 2001 From: David Smith Date: Wed, 3 Feb 2010 11:56:58 -0600 Subject: Fixed PR 11078. Changed code to avoided procfs race condition. * runtime/procfs.c: Allow STP_MAX_PROCFS_FILES define to be overridden. (_stp_create_procfs): Calls proc_create() instead of create_proc_entry() to avoid a race condition. * runtime/procfs-probes.c: New file containing procfs probe support routines. * tapset-procfs.cxx (procfs_derived_probe::join_group): Update struct _stp_procfs_data definition. (procfs_derived_probe::emit_module_decls): Include procfs-probes.c, which is where the definition of struct stap_procfs_probe exists. Update generated routines to read/write procfs data. (procfs_derived_probe_group::emit_module_init): Pass file_operations argument to _stp_create_procfs(). Initialize mutex. (procfs_var_expanding_visitor::visit_target_symbol): Update generated code. --- runtime/procfs.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) (limited to 'runtime/procfs.c') diff --git a/runtime/procfs.c b/runtime/procfs.c index 1d2ad837..1fd9fcc5 100644 --- a/runtime/procfs.c +++ b/runtime/procfs.c @@ -17,7 +17,10 @@ #ifndef _STP_PROCFS_C_ #define _STP_PROCFS_C_ +#ifndef STP_MAX_PROCFS_FILES #define STP_MAX_PROCFS_FILES 16 +#endif + static int _stp_num_pde = 0; static struct proc_dir_entry *_stp_pde[STP_MAX_PROCFS_FILES]; static struct proc_dir_entry *_stp_procfs_files[STP_MAX_PROCFS_FILES]; @@ -131,7 +134,8 @@ static struct proc_dir_entry *_stp_procfs_lookup(const char *dir, struct proc_di return NULL; } -static int _stp_create_procfs(const char *path, int num) +static int _stp_create_procfs(const char *path, int num, + const struct file_operations *fops) { const char *p; char *next; @@ -182,15 +186,18 @@ static int _stp_create_procfs(const char *path, int num) if (_stp_num_pde == STP_MAX_PROCFS_FILES) goto too_many; - de = create_proc_entry (p, 0600, last_dir); + de = proc_create(p, 0600, last_dir, fops); if (de == NULL) { _stp_error("Could not create file \"%s\" in path \"%s\"\n", p, path); goto err; } - _stp_pde[_stp_num_pde++] = de; - _stp_procfs_files[num] = de; +#ifdef AUTOCONF_PROCFS_OWNER + de->owner = THIS_MODULE; +#endif de->uid = _stp_uid; de->gid = _stp_gid; + _stp_pde[_stp_num_pde++] = de; + _stp_procfs_files[num] = de; return 0; too_many: -- cgit