[OE-core] [PATCH 02/10] package: Rework PACKAGELOCK based upon sstate for do_packagedata

[Richard Purdie]

I think this lock dates from before we had sstate for do_packagedata.

Since WORKDIR is recipe specific and we write into WORKDIR, we no longer need
any write locks in the do_packagedata code itself, its handled by the sstate
task lock for the final copy in at the end. The final write lock can be simply
removed.

The only time we need read locking is when actually reading data from the
shared directory. We can therefore reduce the window the lock is held
significantly as well, hence improving the speed of packagedata tasks running
in parallel.

Signed-off-by: Richard Purdie <richard.purdie at linuxfoundation.org>
---
 meta/classes/package.bbclass | 23 +++++++++--------------
 1 file changed, 9 insertions(+), 14 deletions(-)

diff --git a/meta/classes/package.bbclass b/meta/classes/package.bbclass
index 07bc37879c6..6f7015d9129 100644
--- a/meta/classes/package.bbclass
+++ b/meta/classes/package.bbclass
@@ -1411,9 +1411,6 @@ fi
     pkgdest = d.getVar('PKGDEST')
     pkgdatadir = d.getVar('PKGDESTWORK')
 
-    # Take shared lock since we're only reading, not writing
-    lf = bb.utils.lockfile(d.expand("${PACKAGELOCK}"), True)
-
     data_file = pkgdatadir + d.expand("/${PN}" )
     f = open(data_file, 'w')
     f.write("PACKAGES: %s\n" % packages)
@@ -1518,7 +1515,6 @@ fi
     if bb.data.inherits_class('allarch', d) and not bb.data.inherits_class('packagegroup', d):
         write_extra_runtime_pkgs(global_variants, packages, pkgdatadir)
 
-    bb.utils.unlockfile(lf)
 }
 emit_pkgdata[dirs] = "${PKGDESTWORK}/runtime ${PKGDESTWORK}/runtime-reverse ${PKGDESTWORK}/runtime-rprovides"
 
@@ -1629,9 +1625,6 @@ python package_do_shlibs() {
 
     shlibswork_dir = d.getVar('SHLIBSWORKDIR')
 
-    # Take shared lock since we're only reading, not writing
-    lf = bb.utils.lockfile(d.expand("${PACKAGELOCK}"), True)
-
     def linux_so(file, needed, sonames, renames, pkgver):
         needs_ldconfig = False
         ldir = os.path.dirname(file).replace(pkgdest + "/" + pkg, '')
@@ -1744,7 +1737,11 @@ python package_do_shlibs() {
     use_ldconfig = bb.utils.contains('DISTRO_FEATURES', 'ldconfig', True, False, d)
 
     needed = {}
+
+    # Take shared lock since we're only reading, not writing
+    lf = bb.utils.lockfile(d.expand("${PACKAGELOCK}"), True)
     shlib_provider = oe.package.read_shlib_providers(d)
+    bb.utils.unlockfile(lf)
 
     for pkg in shlib_pkgs:
         private_libs = d.getVar('PRIVATE_LIBS_' + pkg) or d.getVar('PRIVATE_LIBS') or ""
@@ -1800,8 +1797,6 @@ python package_do_shlibs() {
             d.setVar('pkg_postinst_%s' % pkg, postinst)
         bb.debug(1, 'LIBNAMES: pkg %s sonames %s' % (pkg, sonames))
 
-    bb.utils.unlockfile(lf)
-
     assumed_libs = d.getVar('ASSUME_SHLIBS')
     if assumed_libs:
         libdir = d.getVar("libdir")
@@ -1914,9 +1909,6 @@ python package_do_pkgconfig () {
                             if hdr == 'Requires':
                                 pkgconfig_needed[pkg] += exp.replace(',', ' ').split()
 
-    # Take shared lock since we're only reading, not writing
-    lf = bb.utils.lockfile(d.expand("${PACKAGELOCK}"), True)
-
     for pkg in packages.split():
         pkgs_file = os.path.join(shlibswork_dir, pkg + ".pclist")
         if pkgconfig_provided[pkg] != []:
@@ -1925,6 +1917,9 @@ python package_do_pkgconfig () {
                 f.write('%s\n' % p)
             f.close()
 
+    # Take shared lock since we're only reading, not writing
+    lf = bb.utils.lockfile(d.expand("${PACKAGELOCK}"), True)
+
     # Go from least to most specific since the last one found wins
     for dir in reversed(shlibs_dirs):
         if not os.path.exists(dir):
@@ -1940,6 +1935,8 @@ python package_do_pkgconfig () {
                 for l in lines:
                     pkgconfig_provided[pkg].append(l.rstrip())
 
+    bb.utils.unlockfile(lf)
+
     for pkg in packages.split():
         deps = []
         for n in pkgconfig_needed[pkg]:
@@ -1957,8 +1954,6 @@ python package_do_pkgconfig () {
             for dep in deps:
                 fd.write(dep + '\n')
             fd.close()
-
-    bb.utils.unlockfile(lf)
 }
 
 def read_libdep_files(d):
-- 
2.17.1