Link: http://lkml.kernel.org/r/20160701130914.GA23225@styxhp Signed-off-by: Florian Meier <Florian.Meier@informatik.uni-erlangen.de> Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Tested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Enabling gcov is counterproductive to compile testing: it significantly increases the kernel image size, compile time, and it produces lots of false positive "may be used uninitialized" warnings as the result of missed optimizations. This is in line with how UBSAN_SANITIZE_ALL and PROFILE_ALL_BRANCHES work, both of which have similar problems. With an ARM allmodconfig kernel, I see the build time drop from 283 minutes CPU time to 225 minutes, and the vmlinux size drops from 43MB to 26MB. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Michal Marek <mmarek@suse.com>
An exact mapping would be within_module_core(), but at this stage (MODULE_STATE_GOING) the init section is empty, and this is clearer. Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Fix kernel gcov support for GCC 5.1. Similar to commit a992bf836f9
("gcov: add support for GCC 4.9"), this patch takes into account the
existence of a new gcov counter (see gcc's gcc/gcov-counter.def.)
Firstly, it increments GCOV_COUNTERS (to 10), which makes the data
structure struct gcov_info compatible with GCC 5.1.
Secondly, a corresponding counter function __gcov_merge_icall_topn (Top N
value tracking for indirect calls) is included in base.c with the other
gcov counters unused for kernel profiling.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Yuan Pengfei <coolypf@qq.com>
Tested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcov profiling if enabled with other heavy compile-time instrumentation
like KASan could trigger following softlockups:
NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:1]
Modules linked in:
irq event stamp: 22823276
hardirqs last enabled at (22823275): [<ffffffff86e8d10d>] mutex_lock_nested+0x7d9/0x930
hardirqs last disabled at (22823276): [<ffffffff86e9521d>] apic_timer_interrupt+0x6d/0x80
softirqs last enabled at (22823172): [<ffffffff811ed969>] __do_softirq+0x4db/0x729
softirqs last disabled at (22823167): [<ffffffff811edfcf>] irq_exit+0x7d/0x15b
CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 3.19.0-05245-gbb33326-dirty #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5.1-0-g8936dbb-20141113_115728-nilsson.home.kraxel.org 04/01/2014
task: ffff88006cba8000 ti: ffff88006cbb0000 task.ti: ffff88006cbb0000
RIP: kasan_mem_to_shadow+0x1e/0x1f
Call Trace:
strcmp+0x28/0x70
get_node_by_name+0x66/0x99
gcov_event+0x4f/0x69e
gcov_enable_events+0x54/0x7b
gcov_fs_init+0xf8/0x134
do_one_initcall+0x1b2/0x288
kernel_init_freeable+0x467/0x580
kernel_init+0x15/0x18b
ret_from_fork+0x7c/0xb0
Kernel panic - not syncing: softlockup: hung tasks
Fix this by sticking cond_resched() in gcov_enable_events().
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
CONFIG_GCOV_FORMAT_3_4 / _4_7 / _AUTODETECT are exclusive. Compare the CC version only when _AUTODETECT is enabled. This change should have no impact. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
Kbuild descends into kernel/gcov/ directory only when CONFIG_GCOV_KERNEL is enabled. (See kernel/Makefile) CONFIG_GCOV_KERNEL check can be omitted in kernel/gcov/Makefile. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
Since commit 371fdc77af44 (kbuild: collect shorthands into scripts/Kbuild.include), scripts/Makefile.clean includes scripts/Kbuild.include. The workaround and the comment block in kernel/gcov/Makefile are no longer necessary. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
The macros cc-version, cc-fullversion and ld-version take no argument. It is not necessary to add $(call ...) to invoke them. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Acked-by: Helge Deller <deller@gmx.de> [parisc] Signed-off-by: Michal Marek <mmarek@suse.cz>
Following the suggestions from Andrew Morton and Stephen Rothwell, Dont expand the ARCH list in kernel/gcov/Kconfig. Instead, define a ARCH_HAS_GCOV_PROFILE_ALL bool which architectures can enable. set ARCH_HAS_GCOV_PROFILE_ALL on Architectures where it was previously allowed + ARM64 which I tested. Signed-off-by: Riku Voipio <riku.voipio@linaro.org> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>