Re: [RFC] [PATCH 3/7] Execution out of line (XOL)

2010-01-15 Thread Srikar Dronamraju
* Peter Zijlstra pet...@infradead.org [2010-01-15 10:07:35]:

 On Thu, 2010-01-14 at 14:43 -0800, Jim Keniston wrote:
  
  Yeah, there's not a lot of context there.  I hope it will make more
  sense if you read section 1.1 of Documentation/uprobes.txt (patch #6).
  Or look at get_insn_slot() in kprobes, and understand that we're trying
  to do something similar in uprobes, where the instruction copies have to
  reside in the user address space of the probed process.
 
 That's not the point, changelogs shoulnd not be this cryptic. They
 should be stand alone and descriptive of what, why and how.
 
 If you can't be bothered writing such for something you want reviewed
 for inclusion then I might not be bothered looking at them at all.
 

Okay shall add to the Changelog with the information providing the
context for this patch.



Re: [RFC] [PATCH 3/7] Execution out of line (XOL)

2010-01-15 Thread Jim Keniston

On Fri, 2010-01-15 at 10:07 +0100, Peter Zijlstra wrote:
 On Thu, 2010-01-14 at 14:43 -0800, Jim Keniston wrote:
  
  Yeah, there's not a lot of context there.  I hope it will make more
  sense if you read section 1.1 of Documentation/uprobes.txt (patch #6).
  Or look at get_insn_slot() in kprobes, and understand that we're trying
  to do something similar in uprobes, where the instruction copies have to
  reside in the user address space of the probed process.
 
 That's not the point, changelogs shoulnd not be this cryptic. They
 should be stand alone and descriptive of what, why and how.

Point taken.

 
 If you can't be bothered writing such for something you want reviewed
 for inclusion then I might not be bothered looking at them at all.
 

We appreciate your persistence wrt this patch set. :-}

Jim



Re: [RFC] [PATCH 3/7] Execution out of line (XOL)

2010-01-14 Thread Peter Zijlstra
On Mon, 2010-01-11 at 17:55 +0530, Srikar Dronamraju wrote:
 Execution out of line (XOL)
 
 Slot allocation mechanism for Execution Out of Line strategy in User
 space breakpointing Inftrastructure. (XOL)
 
 This patch provides slot allocation mechanism for execution out of
 line strategy for use with user space breakpoint infrastructure.
 This patch requires utrace support in kernel.
 
 This patch provides five functions xol_get_insn_slot(),
 xol_free_insn_slot(), xol_put_area(), xol_get_area() and
 xol_validate_vaddr().
 
 Current slot allocation mechanism:
 1. Allocate one dedicated slot per user breakpoint.
 2. If the allocated vma is completely used, expand current vma.
 3. If we cant expand the vma, allocate a new vma.


Say what?

I see the text, but non of it makes any sense at all.



Re: [RFC] [PATCH 3/7] Execution out of line (XOL)

2010-01-14 Thread Jim Keniston

On Thu, 2010-01-14 at 12:08 +0100, Peter Zijlstra wrote:
 On Mon, 2010-01-11 at 17:55 +0530, Srikar Dronamraju wrote:
  Execution out of line (XOL)
  
  Slot allocation mechanism for Execution Out of Line strategy in User
  space breakpointing Inftrastructure. (XOL)
  
  This patch provides slot allocation mechanism for execution out of
  line strategy for use with user space breakpoint infrastructure.
  This patch requires utrace support in kernel.
  
  This patch provides five functions xol_get_insn_slot(),
  xol_free_insn_slot(), xol_put_area(), xol_get_area() and
  xol_validate_vaddr().
  
  Current slot allocation mechanism:
  1. Allocate one dedicated slot per user breakpoint.
  2. If the allocated vma is completely used, expand current vma.
  3. If we cant expand the vma, allocate a new vma.
 
 
 Say what?
 
 I see the text, but non of it makes any sense at all.
 

Yeah, there's not a lot of context there.  I hope it will make more
sense if you read section 1.1 of Documentation/uprobes.txt (patch #6).
Or look at get_insn_slot() in kprobes, and understand that we're trying
to do something similar in uprobes, where the instruction copies have to
reside in the user address space of the probed process.

Jim