aboutsummaryrefslogtreecommitdiff
path: root/arch/powerpc
diff options
context:
space:
mode:
authorNaveen N. Rao2017-06-29 23:19:17 +0530
committerMichael Ellerman2017-07-03 23:12:00 +1000
commit266de3a842d70b481ef1dac487acfad1240deb7e (patch)
treea449d0478c0d9d357e3d579eb6e207ffd2e0c937 /arch/powerpc
parentcf7d6fb0672668690ba235280698c9aa6a81010a (diff)
powerpc/64s: Move system_call() symbol to just after setting MSR_EE
It is common to get a PMU interrupt right after the mtmsr instruction that enables interrupts. Due to this, the stack trace profile gets needlessly split across system_call_common() and system_call(). Previously, system_call() symbol was at the current place to hide a few earlier symbols which have since been made private or removed entirely. So, let's move system_call() slightly higher up, right after the mtmsr instruction that enables interrupts. Convert existing references to system_call to a local syscall symbol. Suggested-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc')
-rw-r--r--arch/powerpc/kernel/entry_64.S7
1 files changed, 4 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 410e19295259..e5cf98d755db 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -143,6 +143,7 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR)
mtmsrd r11,1
#endif /* CONFIG_PPC_BOOK3E */
+system_call: /* label this so stack traces look sane */
/* We do need to set SOFTE in the stack frame or the return
* from interrupt will be painful
*/
@@ -156,7 +157,7 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR)
cmpldi 0,r0,NR_syscalls
bge- .Lsyscall_enosys
-system_call: /* label this so stack traces look sane */
+.Lsyscall:
/*
* Need to vector to 32 Bit or default sys_call_table here,
* based on caller's run-mode / personality.
@@ -310,13 +311,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
ld r7,GPR7(r1)
ld r8,GPR8(r1)
- /* Repopulate r9 and r10 for the system_call path */
+ /* Repopulate r9 and r10 for the syscall path */
addi r9,r1,STACK_FRAME_OVERHEAD
CURRENT_THREAD_INFO(r10, r1)
ld r10,TI_FLAGS(r10)
cmpldi r0,NR_syscalls
- blt+ system_call
+ blt+ .Lsyscall
/* Return code is already in r3 thanks to do_syscall_trace_enter() */
b .Lsyscall_exit