PR16806: tweak test case to guarantee stoppage better
We run the "./loop" executable under /usr/bin/timeout control, but on
RHEL6, uprobes can take a while to sync up for some reason, leading to
a testsuite hang. Switch to timeout -s KILL, moohahahaha, from orbit.
stp: rt: replace stp_print lock with stp style lock
-rt mode preemptable spin lock lead to deadlock causes x86 box to freeze.
Replacing spin lock with stp type raw lock solves the problem. Observed
deadlock in make installcheck testsuite for sched_switch.stp test case.
stp: rt: replace addr_map_lock rd/wr lock with stp type raw lock
Without this change, Noticed that make installcheck freezes x86_64 box, testing
done on IvyBridge v2 12 core (HT). With crash post mortem analysis observed
that multiple threads grabs rd lock and get preempted in rt mode which
shouldn't ideally be the expected flow. rd/wr lock is preemptible which is
causing this problem for -rt mode so replace them with stp style raw lock.
However I poited out in other patches that replacement of rd/wr with rcu lock
in general better approach, we'll revisit them later(todo).
Note : This module afaiu is prime candidate to benifit rcu locking primitives
and same some cycle, should improve overall performance, more scallable.
[This is general desing improvement so keeping those changes out from this
patch. .todo]
Replacing rd/wr lock with raw lock supress these bug_on. However more suitable
fix is to replace read/write lock in general with RCU style lock, followed by
use of rcu variant hlist api but current module desing need to go through some
real desing chnages in order of adding and freeing entry to/from free list,
which i choose work upon as separate patch[todo.]
Locking helper api used for replacing -rt and non-rt specific locks with common
helper lock starts with prefix stp_. -rt version of locking api compatible to
kernel version 3.0 and greater. Older -rt version can be supported by adding
more kernel version checks, ifdefs in header file.. I haven't tested on
those(older) kernel version so not including code for now. Tested for
3.10.40-rt38 and 3.14.12-rt9.
Martin Cermak [Tue, 23 Sep 2014 07:03:02 +0000 (09:03 +0200)]
PR16716 partial fix: Fix types and compat support in timer syscalls family
* tapset/linux/syscalls2.stp:
syscall.timer_{delete,getoverrun,gettime,settime}: Fix types
syscall.timer_gettime: Add compat support
* tapset/linux/nd_syscalls2.stp (timer_gettime): Add compat support
* tapset/linux/aux_syscalls.stp: Print the pointer value
when _stp_copy_from_user() fails instead of reporting "UNKNOWN"
* testsuite/systemtap.syscall/test.tcl: Link with -lrt to allow
using glibc wrappers for timer syscalls family
* testsuite/systemtap.syscall/timer.c: Add more tests
Josh Stone [Fri, 12 Sep 2014 22:51:10 +0000 (15:51 -0700)]
stapdyn: use process_vm_readv/writev when possible
For script deref uses, we were using pread/pwrite on /proc/self/mem.
But thanks to CVE-2012-0056, some kernels have completely disabled
mem_write, so stapdyn guru scripts can't write memory at all. Our
testsuite failed on at_var_lvalue.exp and deref.exp in this case.
When the process_vm_readv/writev syscalls are available, we can
accomplish the same thing, and don't even need an open fd for it.
Jonathan Lebon [Fri, 12 Sep 2014 20:53:42 +0000 (16:53 -0400)]
initscript: also delete uprobes.ko during cleanup
If after cleanup we've removed all the scripts that require uprobes.ko,
then we should also delete uprobes.ko itself. It will be copied back in
the cache directory the next time a uprobes.ko dependent script is
compiled.
systemtap-initscript scripts that rely on uprobes must be configured
with the --save-uprobes option. This option saves the generated
uprobes.ko module and loads it when running the script.
The uprobes dependency information is actually available at compile time
so we can autodetect as follows:
1. Check if uprobes.ko was generated during compile
2. When uprobes.ko was generated, touch <name>.uprobes in the cache
directory.
3. Add the staprun -u option if <name>.uprobes exists
It is no longer necessary to specify the --save-uprobes option in the
initscript configuration file, although doing so allowed.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Jonathan Lebon [Fri, 12 Sep 2014 18:06:08 +0000 (14:06 -0400)]
PR17190: accept functions given with their decl_line
If the user gives a probe for a specific function, e.g.
kernel.function("vfs_read@fs/read_write.c:393")
where the vfs_read() function is declared at lineno 393, we don't
actually want to probe lineno 393 (most likely there's nothing there
anyway). We simply need to probe the function's entry point.
Jonathan Lebon [Mon, 8 Sep 2014 21:17:59 +0000 (17:17 -0400)]
nearest probes: preserve user-entered lineno in chain
This patch adds an earlier well-formed probe point in the derivation
chain of .nearest probes so that the original lineno entered is
retained during stap -l.
Martin Cermak [Wed, 10 Sep 2014 18:21:16 +0000 (20:21 +0200)]
server.exp: fix condition affecting avahi related subtests
On systemd based systems, /usr/sbin/service calls /bin/systemctl.
Unlike rhel6's /sbin/service, systemctl logs to stderr even in case
of successful service restart. Tcl's exec(), called from the as_root(),
is by default sensitive to stderr, and produced false failure.
Josh Stone [Wed, 3 Sep 2014 23:37:06 +0000 (16:37 -0700)]
Remove systemtap_session::built_uprobes
For the purpose of save_uprobes, it doesn't actually matter whether
uprobes.ko was just built or was pulled from the cache. If we have the
uprobes_path at all, go ahead and save it.
Jonathan Lebon [Wed, 3 Sep 2014 21:45:33 +0000 (17:45 -0400)]
initscript: use --save-uprobes instead of -u
Rather than masking the -u option of stap (unoptimized mode), use the
actual option which we use with stap (--save-uprobes). This will allow
us to remain backwards-compatible if we later on automate the uprobes
saving by always turning on --save-uprobes.
So now, users have to do the following if they require userspace
probing:
Stefan Hajnoczi [Wed, 3 Sep 2014 21:38:30 +0000 (17:38 -0400)]
stap: add --save-uprobes
The stap -m <name> option saves the script module. For scripts that
rely on uprobes it may also be necessary to get the uprobes module (if
it was built by stap).
The new stap --save-uprobes option saves uprobes/uprobes.ko into the
current directory.
jistone noted that the smp_call_function_single() function call
introduced in commit 590a9ae1acc47 didn't exist on 2.6.9-era kernels.
We de-optimize to plain smp_call_function() on such dinosaurs.
Josh Stone [Fri, 29 Aug 2014 22:15:47 +0000 (15:15 -0700)]
PR12333: Use 1/0 conditions instead of true/false in C
The kernel happens to declare true/false values for C to use, at least
since commit 6e21828743247 (in 2.6.19), but stapdyn's normal C runtime
doesn't have that. Use boring old 1/0 instead.
Abegail Jakop [Thu, 28 Aug 2014 19:08:59 +0000 (15:08 -0400)]
PR12333: deleting pmap specified by array slice
runtime/map.c: have iterdel() use pre-existing functions
translate.cxx: generate code to delete elements from a pmap, based on
an array slice given. rename next() that called iterdel to del_next()
staptree.cxx: cleanup of an unnecessary condition
Abegail Jakop [Tue, 26 Aug 2014 19:53:22 +0000 (15:53 -0400)]
store given pid for process probe for use by task_finder
session.cxx: replace readlink(), which did the pid validation,
with is_valid_pid()
tapsets.cxx: if given, within dwarf_builder::build store the pid
for use by uprobe_derived_probe so that task_finder associates
the probe with the pid
util.*: new function that checks if the given pid is valid. if
not, it generates an error message that can be used.
Abegail Jakop [Fri, 22 Aug 2014 20:52:33 +0000 (16:52 -0400)]
PR12333: store wildcards in array slices as NULL
parse.cxx: set the index for array slices as NULL if it's a wildcard
elaborate.cxx: account for NULL indexes. added error message in
symresolution_info::visit_arrayindex if it encounters a NULL index,
since all expressions that support wildcards dealt with separately
staptree.cxx: when printing out foreach, delete and array_in, replace
NULL indexes with "*"
translate.cxx: account for NULL indexes. don't generate a tmpvar
for a wildcard array index
Abegail Jakop [Thu, 21 Aug 2014 16:17:40 +0000 (12:17 -0400)]
PR12333" array slicing for membership test
parse.cxx: accept wildcards in the arrayindex for array_in
elaborate.cxx: new function symresolution_info::visit_array_in
that skips processing wildcards that are present in the arrayindex
translate.cxx: generate code to iterate over the array until a
match is found or until the end of the array
Abegail Jakop [Tue, 19 Aug 2014 18:12:52 +0000 (14:12 -0400)]
PR12333: array slicing for delete statements
parse.cxx: accept wildcards (*) within array indexes
elaborate.cxx: skip processing wildcards in array indexes for delete
staptree.cxx: for the varuse_collecting_visitor, don't throw an error
about no referent if the symbol is a wildcard
translate.cxx: generate code for deleting variables if the indexes match
the array slice given. Also generate code to initialize tmpvars used to
store indexes in the array slice.
runtime/map.c: new function _stp_map_iterdel that deletes the node given,
and returns the next node in the map.
Frank Ch. Eigler [Sun, 17 Aug 2014 14:55:35 +0000 (10:55 -0400)]
runtime: improve robustness of shutdown phase via flush_scheduled_work()
It has been observed that schedule_work() artifacts have the potential
to overstay their welcome during shutdown, triggering some time after
their operand data structures have been deallocated. This has shown
up most recently on 3.17-rc0 during the on-the-fly stress-testing, but
also can be observed with plain pseudo-utrace callbacks. We now add a
flush_scheduled_work() into our cargo-cult stp_synchronize_sched(),
which we now call during the on-the-fly shutdown phase too.
Normal optimized mode can make it difficult to see which stap probe
was being invoked for which C probe handler body, as identical probe
handlers are reused. This is inconvenient if one just has a kernel
crash backtrace to start from from.
* translate.cxx (emit_common_header, emit_probe): In -u mode,
eschew duplicate probe handler body elision.
Abegail Jakop [Fri, 15 Aug 2014 20:33:33 +0000 (16:33 -0400)]
PR12333: evaluating the indexes before the loop body
translate.cxx: evaluate the expressions that make up the array slice
index for foreach loops. updated c_tmpcounter::visit_foreach_loop to
account for the additional tmpvars used to store array slice indexes
David Smith [Fri, 15 Aug 2014 20:07:52 +0000 (15:07 -0500)]
Fix PR17275 by fixing testcase problems on s390x.
* testsuite/buildok/memory-all-probes.stp: Tweak test to avoid overly
broad wildcards, which can cause the test to fail on systems without
uprobes (like s390x).
* testsuite/buildok/tcp-all-probes.stp: Ditto.
David Smith [Thu, 14 Aug 2014 18:49:44 +0000 (13:49 -0500)]
Improve on-the-fly initialization code.
* translate.cxx (c_unparser::emit_probe_condition_initialize): Only output
'cond_enabled' field initialization if the probe isn't always enabled.
(translate_pass): Always initialize 'cond_enabled' to 1. This can get
overridden by the output of
c_unparser::emit_probe_condition_initialize().
git://sourceware.org / systemtap.git / log