Commit Graph

8 Commits

Author SHA1 Message Date
fabient
5edfb77dd3 Add software PMC support.
New kernel events can be added at various location for sampling or counting.
This will for example allow easy system profiling whatever the processor is
with known tools like pmcstat(8).

Simultaneous usage of software PMC and hardware PMC is possible, for example
looking at the lock acquire failure, page fault while sampling on
instructions.

Sponsored by: NETASQ
MFC after:	1 month
2012-03-28 20:58:30 +00:00
fabient
f0b6964bba Fix memory leak on error.
Found with:	Coverity Prevent(tm)
MFC after:	1 month
2010-06-05 23:00:02 +00:00
jkoshy
aa86a7c59e - Add support for PMCs in Intel CPUs of Family 6, model 0xE (Core Solo
and Core Duo), models 0xF (Core2), model 0x17 (Core2Extreme) and
  model 0x1C (Atom).

  In these CPUs, the actual numbers, kinds and widths of PMCs present
  need to queried at run time.  Support for specific "architectural"
  events also needs to be queried at run time.

  Model 0xE CPUs support programmable PMCs, subsequent CPUs
  additionally support "fixed-function" counters.

- Use event names that are close to vendor documentation, taking in
  account that:
  - events with identical semantics on two or more CPUs in this family
    can have differing names in vendor documentation,
  - identical vendor event names may map to differing events across
    CPUs,
  - each type of CPU supports a different subset of measurable
    events.

  Fixed-function and programmable counters both use the same vendor
  names for events.  The use of a class name prefix ("iaf-" or
  "iap-" respectively) permits these to be distinguished.

- In libpmc, refactor pmc_name_of_event() into a public interface
  and an internal helper function, for use by log handling code.

- Minor code tweaks: staticize a global, freshen a few comments.

Tested by:	gnn
2008-11-27 09:00:47 +00:00
jkoshy
86277bac23 Add callchain parsing to -lpmc.
Sponsored by:	FreeBSD Foundation and Google Inc.
2007-12-03 11:15:46 +00:00
jkoshy
48e5e4792d MFP4: Support for profiling dynamically loaded objects.
Kernel changes:

  Inform hwpmc of executable objects brought into the system by
  kldload() and mmap(), and of their removal by kldunload() and
  munmap().  A helper function linker_hwpmc_list_objects() has been
  added to "sys/kern/kern_linker.c" and is used by hwpmc to retrieve
  the list of currently loaded kernel modules.

  The unused `MAPPINGCHANGE' event has been deprecated in favour
  of separate `MAP_IN' and `MAP_OUT' events; this change reduces
  space wastage in the log.

  Bump the hwpmc's ABI version to "2.0.00".  Teach hwpmc(4) to
  handle the map change callbacks.

  Change the default per-cpu sample buffer size to hold
  32 samples (up from 16).

  Increment __FreeBSD_version.

libpmc(3) changes:

  Update libpmc(3) to deal with the new events in the log file; bring
  the pmclog(3) manual page in sync with the code.

pmcstat(8) changes:

  Introduce new options to pmcstat(8): "-r" (root fs path), "-M"
  (mapfile name), "-q"/"-v" (verbosity control).  Option "-k" now
  takes a kernel directory as its argument but will also work with
  the older invocation syntax.

  Rework string handling in pmcstat(8) to use an opaque type for
  interned strings.  Clean up ELF parsing code and add support for
  tracking dynamic object mappings reported by a v2.0.00 hwpmc(4).

  Report statistics at the end of a log conversion run depending
  on the requested verbosity level.

Reviewed by:	jhb, dds (kernel parts of an earlier patch)
Tested by:	gallatin (earlier patch)
2006-03-26 12:20:54 +00:00
jkoshy
51f3adcc08 Fix a bug in pmclog_read() that causes it to return with a false
error when a log record crosses an internal buffer boundary.

Approved by:	re (scottl)
2005-07-09 17:12:30 +00:00
jkoshy
3cade8d074 MFP4:
- pmcstat(8) gprof output mode fixes:

  lib/libpmc/pmclog.{c,h}, sys/sys/pmclog.h:
  + Add a 'is_usermode' field to the PMCLOG_PCSAMPLE event
  + Add an 'entryaddr' field to the PMCLOG_PROCEXEC event,
    so that pmcstat(8) can determine where the runtime loader
    /libexec/ld-elf.so.1 is getting loaded.

  sys/kern/kern_exec.c:
  + Use a local struct to group the entry address of the image being
    exec()'ed and the process credential changed flag to the exec
    handling hook inside hwpmc(4).

  usr.sbin/pmcstat/*:
  + Support "-k kernelpath", "-D sampledir".
  + Implement the ELF bits of 'gmon.out' profile generation in a new
    file "pmcstat_log.c".  Move all log related functions to this
    file.
  + Move local definitions and prototypes to "pmcstat.h"

- Other bug fixes:
  + lib/libpmc/pmclog.c: correctly handle EOF in pmclog_read().
  + sys/dev/hwpmc_mod.c: unconditionally log a PROCEXIT event to all
    attached PMCs when a process exits.
  + sys/sys/pmc.h: correct a function prototype.
  + Improve usage checks in pmcstat(8).

Approved by:	re (blanket hwpmc)
2005-06-30 19:01:26 +00:00
jkoshy
1d3209ab83 MFP4:
- Implement sampling modes and logging support in hwpmc(4).

- Separate MI and MD parts of hwpmc(4) and allow sharing of
  PMC implementations across different architectures.
  Add support for P4 (EMT64) style PMCs to the amd64 code.

- New pmcstat(8) options: -E (exit time counts) -W (counts
  every context switch), -R (print log file).

- pmc(3) API changes, improve our ability to keep ABI compatibility
  in the future.  Add more 'alias' names for commonly used events.

- bug fixes & documentation.
2005-06-09 19:45:09 +00:00