[OE-core] [RFC][PATCHv2] cmake.bbclass, perf: don't re-create ${B}

[Martin Jansa]

* otherwise there is race-condition between do_configure rm+mkdir and
  bitbake trying to use it as CWD for do_populate_lic task, which
  results in errors like this:

NOTE: recipe perf-1.0-r9: task do_configure: Started
NOTE: recipe perf-1.0-r9: task do_populate_lic: Started
ERROR: Build of do_populate_lic failed
ERROR: Traceback (most recent call last):
  File "/OE/build/oe-core/bitbake/lib/bb/build.py", line 553, in exec_task
    return _exec_task(fn, task, d, quieterr)
  File "/OE/build/oe-core/bitbake/lib/bb/build.py", line 493, in _exec_task
    exec_func(func, localdata)
  File "/OE/build/oe-core/bitbake/lib/bb/build.py", line 227, in exec_func
    exec_func_python(func, d, runfile, cwd=adir)
  File "/OE/build/oe-core/bitbake/lib/bb/build.py", line 252, in exec_func_python
    os.chdir(cwd)
OSError: [Errno 2] No such file or directory: '/OE/build/oe-core/tmp-glibc/work/qemux86-oe-linux/perf/1.0-r9/perf-1.0'
NOTE: recipe perf-1.0-r9: task do_populate_lic: Failed
ERROR: Task 7 (/OE/build/oe-core/openembedded-core/meta/recipes-kernel/perf/perf.bb, do_populate_lic) failed with exit code '1'
NOTE: recipe perf-1.0-r9: task do_configure: Succeeded

or even longer exception:

NOTE: recipe perf-1.0-r9: task do_populate_lic: Started
NOTE: recipe perf-1.0-r9: task do_configure: Started
ERROR: Error executing a python function in /OE/build/oe-core/openembedded-core/meta/recipes-kernel/perf/perf.bb:

The stack trace of python calls that resulted in this exception/failure was:
File: 'sstate_task_postfunc', lineno: 14, function: <module>
     0010:    sstate_package(shared_state, d)
     0011:    os.umask(omask)
     0012:
     0013:
 *** 0014:sstate_task_postfunc(d)
     0015:
File: 'sstate_task_postfunc', lineno: 4, function: sstate_task_postfunc
     0001:
     0002:def sstate_task_postfunc(d):
     0003:    shared_state = sstate_state_fromvars(d)
 *** 0004:    sstate_install(shared_state, d)
     0005:    for intercept in shared_state['interceptfuncs']:
     0006:        bb.build.exec_func(intercept, d)
     0007:    omask = os.umask(002)
     0008:    if omask != 002:
File: 'sstate.bbclass', lineno: 113, function: sstate_install
     0109:        if os.path.exists(state[1]):
     0110:            oe.path.copyhardlinktree(state[1], state[2])
     0111:
     0112:    for postinst in (d.getVar('SSTATEPOSTINSTFUNCS', True) or '').split():
 *** 0113:        bb.build.exec_func(postinst, d)
     0114:
     0115:    for lock in locks:
     0116:        bb.utils.unlockfile(lock)
     0117:
File: '/OE/build/oe-core/bitbake/lib/bb/build.py', lineno: 227, function: exec_func
     0223:                pass
     0224:
     0225:    with bb.utils.fileslocked(lockfiles):
     0226:        if ispython:
 *** 0227:            exec_func_python(func, d, runfile, cwd=adir)
    0228:        else:
     0229:            exec_func_shell(func, d, runfile, cwd=adir)
     0230:
     0231:_functionfmt = """
File: '/OE/build/oe-core/bitbake/lib/bb/build.py', lineno: 252, function: exec_func_python
     0248:        try:
     0249:            olddir = os.getcwd()
     0250:        except OSError:
     0251:            olddir = None
 *** 0252:        os.chdir(cwd)
     0253:
     0254:    bb.debug(2, "Executing python function %s" % func)
     0255:
     0256:    try:
Exception: OSError: [Errno 2] No such file or directory: '/OE/build/oe-core/tmp-glibc/work/qemux86-oe-linux/perf/1.0-r9/perf-1.0'

ERROR: Function failed: sstate_task_postfunc
ERROR: Logfile of failure stored in: /OE/build/oe-core/tmp-glibc/work/qemux86-oe-linux/perf/1.0-r9/temp/log.do_populate_lic.16588
NOTE: recipe perf-1.0-r9: task do_populate_lic: Failed
ERROR: Task 7 (/OE/build/oe-core/openembedded-core/meta/recipes-kernel/perf/perf.bb, do_populate_lic) failed with exit code '1'
NOTE: recipe perf-1.0-r9: task do_configure: Succeeded
NOTE: Tasks Summary: Attempted 840 tasks of which 835 didn't need to be rerun and 1 failed.

Signed-off-by: Martin Jansa <Martin.Jansa at gmail.com>
---
 meta/classes/cmake.bbclass       | 3 +--
 meta/recipes-kernel/perf/perf.bb | 3 +--
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/meta/classes/cmake.bbclass b/meta/classes/cmake.bbclass
index ae3cc02..e31799a 100644
--- a/meta/classes/cmake.bbclass
+++ b/meta/classes/cmake.bbclass
@@ -91,8 +91,7 @@ cmake_do_configure() {
 	fi
 
 	if [ "${S}" != "${B}" ]; then
-		rm -rf ${B}
-		mkdir -p ${B}
+		find ${B} -mindepth 1 -maxdepth 1 | xargs rm -rf
 		cd ${B}
 	else
 		find ${B} -name CMakeFiles -or -name Makefile -or -name cmake_install.cmake -or -name CMakeCache.txt -delete
diff --git a/meta/recipes-kernel/perf/perf.bb b/meta/recipes-kernel/perf/perf.bb
index 22bd3c8..a5a04af 100644
--- a/meta/recipes-kernel/perf/perf.bb
+++ b/meta/recipes-kernel/perf/perf.bb
@@ -119,8 +119,7 @@ do_install() {
 
 do_configure_prepend () {
     # Fix for rebuilding
-    rm -rf ${B}/
-    mkdir -p ${B}/
+    find ${B} -mindepth 1 -maxdepth 1 | xargs rm -rf
 
     # If building a multlib based perf, the incorrect library path will be
     # detected by perf, since it triggers via: ifeq ($(ARCH),x86_64). In a 32 bit
-- 
2.5.1