user/sven/linux.git/kernel/lockdep_proc.c, branch v2.6.27.8

lockstat: fix numerical output rounding error

2008-08-26T08:37:46Z

Fix rounding error in /proc/lock_stat numerical output. On occasion the two digit fractional part contains the three digit value '100'. This is due to a bug in the rounding algorithm which pushes values in the range '95..99' to '100' rather than to '00' + an increment to the integer part. For example, - 123456.100 old display + 123457.00 new display Signed-off-by: Ingo Molnar

lockdep: fix build if CONFIG_PROVE_LOCKING not defined

2008-08-15T17:22:04Z

If CONFIG_PROVE_LOCKING not defined, then no dependency information is available. Signed-off-by: Stephen Hemminger Signed-off-by: Ingo Molnar

lockdep: handle chains involving classes defined in modules

2008-08-11T07:30:26Z

Solve this by marking the classes as unused and not printing information about the unused classes. Reported-by: Eric Sesterhenn Signed-off-by: Rabin Vincent Acked-by: Huang Ying Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar

lockdep: fix combinatorial explosion in lock subgraph traversal

2008-07-31T16:38:28Z

When we traverse the graph, either forwards or backwards, we are interested in whether a certain property exists somewhere in a node reachable in the graph. Therefore it is never necessary to traverse through a node more than once to get a correct answer to the given query. Take advantage of this property using a global ID counter so that we need not clear all the markers in all the lock_class entries before doing a traversal. A new ID is choosen when we start to traverse, and we continue through a lock_class only if it's ID hasn't been marked with the new value yet. This short-circuiting is essential especially for high CPU count systems. The scheduler has a runqueue per cpu, and needs to take two runqueue locks at a time, which leads to long chains of backwards and forwards subgraphs from these runqueue lock nodes. Without the short-circuit implemented here, a graph traversal on a runqueue lock can take up to (1 << (N - 1)) checks on a system with N cpus. For anything more than 16 cpus or so, lockdep will eventually bring the machine to a complete standstill. Signed-off-by: David S. Miller Acked-by: Peter Zijlstra Signed-off-by: Ingo Molnar

lockdep: add lock_class information to lock_chain and output it

2008-06-23T23:28:20Z

It is based on x86/master branch of git-x86 tree, and has been tested on x86_64 platform. ChangeLog: v2: - Enclosing proc file system related code into CONFIG_PROVE_LOCKING. - Fix nr_chain_hlocks update code. Signed-off-by: Huang Ying Cc: Peter Zijlstra Signed-off-by: Ingo Molnar

lockdep: add lock_class information to lock_chain and output it

2008-06-20T10:21:33Z

This patch records array of lock_class into lock_chain, and export lock_chain information via /proc/lockdep_chains. It is based on x86/master branch of git-x86 tree, and has been tested on x86_64 platform. Signed-off-by: Huang Ying Cc: Peter Zijlstra Signed-off-by: Ingo Molnar

lockdep: output lock_class key instead of address for forward dependency output

2008-06-13T06:55:01Z

The key instead of address of lock_class should be output in /proc/lockdep when forward dependency is output, because key is output for lock_class itself as identifier too. This patch is based on x86/auto-latest branch of git-x86 tree, and has been tested on x86_64 platform. Signed-off-by: Huang Ying Signed-off-by: Ingo Molnar

kernel: use non-racy method for proc entries creation

2008-04-29T15:06:22Z

Use proc_create()/proc_create_data() to make sure that ->proc_fops and ->data be setup before gluing PDE to main tree. Signed-off-by: Denis V. Lunev Cc: Alexey Dobriyan Cc: "Eric W. Biederman" Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lockdep: Avoid /proc/lockdep & lock_stat infinite output

2007-10-11T20:11:11Z

Both /proc/lockdep and /proc/lock_stat output may loop infinitely. When a read() requests an amount of data smaller than the amount of data that the seq_file's foo_show() outputs, the output starts looping and outputs the "stuck" element's data infinitely. There may be multiple sequential calls to foo_start(), foo_next()/foo_show(), and foo_stop() for a single open with sequential read of the file. The _start() does not have to start with the 0th element and _show() might be called multiple times in a row for the same element for a given open/read of the seq_file. Also header output should not be happening in _start(). All output should be in _show(), which SEQ_START_TOKEN is meant to help. Having output in _start() may also negatively impact seq_file's seq_read() and traverse() accounting. Signed-off-by: Tim Pepper Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar Cc: Ingo Molnar Cc: Al Viro

Fix leak on /proc/lockdep_stats

2007-07-31T22:39:40Z

Signed-off-by: Alexey Dobriyan Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds