On 2016-10-19 17:56:30 [+0200], Mike Galbraith wrote:
> In v4.7, the driver switched to percpu compression streams, disabling
> preemption vai get/put_cpu_ptr(). Use a local lock instead for RT.
> We also have to fix an RT lock order issue in zram_decompress_page()
> such that zs_map_object() nests inside of zcomp_stream_put() as it
> does in zram_bvec_write().
good. I almost had it myself. So let me get that one. And your previous
one (the spinlock replacement) looks also reasonable. With this hunk
@@ -313,6 +314,7 @@ struct mapping_area {
#endif
char *vm_addr; /* address of kmap_atomic()'ed pages */
enum zs_mapmode vm_mm; /* mapping mode */
+ spinlock_t ma_lock;
};
#ifdef CONFIG_COMPACTION
@@ -1489,6 +1491,7 @@ void *zs_map_object(struct zs_pool *pool, unsigned long handle,
off = (class->size * obj_idx) & ~PAGE_MASK;
area = per_cpu_ptr(&zs_map_area, get_cpu_light());
+ spin_lock(&area->ma_lock);
area->vm_mm = mm;
if (off + class->size <= PAGE_SIZE) {
/* this object is contained entirely within a page */
@@ -1542,6 +1545,7 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
__zs_unmap_object(area, pages, off, class->size);
}
+ spin_unlock(&area->ma_lock);
put_cpu_light();
migrate_read_unlock(zspage);
I don't see this anymore:
|gcc: internal compiler error: Killed (program cc1)
|Please submit a full bug report,
|with preprocessed source if appropriate.
|See <file:///usr/share/doc/gcc-6/README.Bugs> for instructions.
|Makefile:134: recipe for target 'servconf.o' failed
|make: *** [servconf.o] Error 4
|make: *** Waiting for unfinished jobs....
|
|
|loginrec.c:1722:1: internal compiler error: Bus error
| }
| ^
only
|gcc: internal compiler error: Killed (program cc1)
which is expected.
> Signed-off-by: Mike Galbraith <umgwanakikbuti@xxxxxxxxx>
Sebastian
--
To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
