On Tue, Mar 31, 2009 at 4:00 PM, <kristrev@xxxxxxxxx> wrote: >> sounds like u need a mutex or semaphore lock. not the spinlock type, >> nevertheless, pick your choice: >> >> c06f5040 T _read_trylock >> c06f5028 T _spin_trylock >> c06f5154 T _spin_trylock_bh >> c06f5061 T _write_trylock >> c0444958 T down_read_trylock >> c0444ec4 T down_trylock >> c0444978 T down_write_trylock >> c06f4096 T mutex_trylock >> c044e86e t rt_mutex_slowtrylock >> c06f4844 T rt_mutex_trylock >> c067ccc2 T rtnl_trylock > > Thank you, I will look into those. > >> >> but sorry, why "proc-variable" need bh-kind of lock? > > When reading/writing to a proc-variable, a softirq is triggered. And since any specific scenario where this can happened? as far as i know, procfs is just a filesystem, and when u read/write to it, it gets treated as a filesystem operation: fs/proc/: http://www.faqs.org/docs/kernel/x716.html http://ww2.cs.fsu.edu/~rosentha/linux/2.6.26.5/docs/DocBook/procfs-guide/index.html http://linuxgazette.net/115/nirendra.html http://en.wikipedia.org/wiki/Procfs whereas softirq are handled via a kernel thread: ksoftirqd. correctly? As for executing procfs operation inside the ksoftirqd context, I am not sure if it will happen or not, or what will happen if procfs operation is executed. (by operations I meant for example: fs/proc/base.c: base.c:static const struct file_operations proc_lstats_operations = { base.c:static const struct file_operations proc_mounts_operations = { base.c:static const struct file_operations proc_mountinfo_operations = { base.c:static const struct file_operations proc_mountstats_operations = { base.c:static const struct file_operations proc_info_file_operations = { base.c:static const struct file_operations proc_single_file_operations = { base.c:static const struct file_operations proc_mem_operations = { base.c:static const struct file_operations proc_environ_operations = { base.c:static const struct file_operations proc_oom_adjust_operations = { base.c:static const struct file_operations proc_loginuid_operations = { base.c:static const struct file_operations proc_sessionid_operations = { base.c:static const struct file_operations proc_fault_inject_operations = { base.c:static const struct file_operations proc_pid_sched_operations = { base.c:static const struct file_operations proc_fdinfo_file_operations = { base.c:static const struct file_operations proc_fd_operations = { ?????? > the read/write-functions of my proc variable is accsessing a shared value, > I need to have locks that disable softirqs for the time being. > > -Kristian > > -- Regards, Peter Teoh -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
