MIPS: CM: Drop WARN_ON(vp != 0)
authorJames Hogan <jhogan@kernel.org>
Tue, 5 Dec 2017 22:28:22 +0000 (22:28 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 23 Jan 2018 18:58:19 +0000 (19:58 +0100)
commit c04de7b1ad645b61c141df8ca903ba0cc03a57f7 upstream.

Since commit 68923cdc2eb3 ("MIPS: CM: Add cluster & block args to
mips_cm_lock_other()"), mips_smp_send_ipi_mask() has used
mips_cm_lock_other_cpu() with each CPU number, rather than
mips_cm_lock_other() with the first VPE in each core. Prior to r6,
multicore multithreaded systems such as dual-core dual-thread
interAptivs with CPU Idle enabled (e.g. MIPS Creator Ci40) results in
mips_cm_lock_other() repeatedly hitting WARN_ON(vp != 0).

There doesn't appear to be anything fundamentally wrong about passing a
non-zero VP/VPE number, even if it is a core's region that is locked
into the other region before r6, so remove that particular WARN_ON().

Fixes: 68923cdc2eb3 ("MIPS: CM: Add cluster & block args to mips_cm_lock_other()")
Signed-off-by: James Hogan <jhogan@kernel.org>
Reviewed-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17883/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/mips/kernel/mips-cm.c

index dd5567b..8f5bd04 100644 (file)
@@ -292,7 +292,6 @@ void mips_cm_lock_other(unsigned int cluster, unsigned int core,
                                  *this_cpu_ptr(&cm_core_lock_flags));
        } else {
                WARN_ON(cluster != 0);
-               WARN_ON(vp != 0);
                WARN_ON(block != CM_GCR_Cx_OTHER_BLOCK_LOCAL);
 
                /*