[GIT PULL] s390 patches for 4.18-rc4
From: Martin Schwidefsky
Date: Fri Jul 06 2018 - 02:59:31 EST
Hi Linus,
please pull from the 'for-linus' branch of
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git for-linus
to receive the following updates:
A few more changes for v4.18:
- Wire up the two new system calls io_pgetevents and rseq
- Fix a register corruption in the expolines code for machines without EXRL
- Drastically reduce the memory utilization of the dasd driver
- Fix reference counting for KVM page table pages
Christian Borntraeger (1):
s390: Correct register corruption in critical section cleanup
Eric Farman (1):
s390/mm: fix refcount usage for 4K pgste
Heiko Carstens (2):
s390: wire up io_pgetevents system call
s390: wire up rseq system call
Stefan Haberland (1):
s390/dasd: reduce the default queue depth and nr of hardware queues
arch/s390/Kconfig | 1 +
arch/s390/kernel/compat_wrapper.c | 1 +
arch/s390/kernel/entry.S | 8 ++++++--
arch/s390/kernel/signal.c | 3 ++-
arch/s390/kernel/syscalls/syscall.tbl | 2 ++
arch/s390/mm/pgalloc.c | 4 ++++
drivers/s390/block/dasd.c | 13 +++++++++++--
drivers/s390/block/dasd_int.h | 8 --------
8 files changed, 27 insertions(+), 13 deletions(-)
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index baed397..e44bb2b 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -160,6 +160,7 @@ config S390
select HAVE_OPROFILE
select HAVE_PERF_EVENTS
select HAVE_REGS_AND_STACK_ACCESS_API
+ select HAVE_RSEQ
select HAVE_SYSCALL_TRACEPOINTS
select HAVE_VIRT_CPU_ACCOUNTING
select MODULES_USE_ELF_RELA
diff --git a/arch/s390/kernel/compat_wrapper.c b/arch/s390/kernel/compat_wrapper.c
index 607c5e9..2ce28bf 100644
--- a/arch/s390/kernel/compat_wrapper.c
+++ b/arch/s390/kernel/compat_wrapper.c
@@ -183,3 +183,4 @@ COMPAT_SYSCALL_WRAP2(s390_guarded_storage, int, command, struct gs_cb *, gs_cb);
COMPAT_SYSCALL_WRAP5(statx, int, dfd, const char __user *, path, unsigned, flags, unsigned, mask, struct statx __user *, buffer);
COMPAT_SYSCALL_WRAP4(s390_sthyi, unsigned long, code, void __user *, info, u64 __user *, rc, unsigned long, flags);
COMPAT_SYSCALL_WRAP5(kexec_file_load, int, kernel_fd, int, initrd_fd, unsigned long, cmdline_len, const char __user *, cmdline_ptr, unsigned long, flags)
+COMPAT_SYSCALL_WRAP4(rseq, struct rseq __user *, rseq, u32, rseq_len, int, flags, u32, sig)
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index f03402e..150130c 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -357,6 +357,10 @@ ENTRY(system_call)
stg %r2,__PT_R2(%r11) # store return value
.Lsysc_return:
+#ifdef CONFIG_DEBUG_RSEQ
+ lgr %r2,%r11
+ brasl %r14,rseq_syscall
+#endif
LOCKDEP_SYS_EXIT
.Lsysc_tif:
TSTMSK __PT_FLAGS(%r11),_PIF_WORK
@@ -1265,7 +1269,7 @@ cleanup_critical:
jl 0f
clg %r9,BASED(.Lcleanup_table+104) # .Lload_fpu_regs_end
jl .Lcleanup_load_fpu_regs
-0: BR_EX %r14
+0: BR_EX %r14,%r11
.align 8
.Lcleanup_table:
@@ -1301,7 +1305,7 @@ cleanup_critical:
ni __SIE_PROG0C+3(%r9),0xfe # no longer in SIE
lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
larl %r9,sie_exit # skip forward to sie_exit
- BR_EX %r14
+ BR_EX %r14,%r11
#endif
.Lcleanup_system_call:
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index 2d2960a..22f0824 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -498,7 +498,7 @@ void do_signal(struct pt_regs *regs)
}
/* No longer in a system call */
clear_pt_regs_flag(regs, PIF_SYSCALL);
-
+ rseq_signal_deliver(&ksig, regs);
if (is_compat_task())
handle_signal32(&ksig, oldset, regs);
else
@@ -537,4 +537,5 @@ void do_notify_resume(struct pt_regs *regs)
{
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
+ rseq_handle_notify_resume(NULL, regs);
}
diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
index 8b210ea..022fc09 100644
--- a/arch/s390/kernel/syscalls/syscall.tbl
+++ b/arch/s390/kernel/syscalls/syscall.tbl
@@ -389,3 +389,5 @@
379 common statx sys_statx compat_sys_statx
380 common s390_sthyi sys_s390_sthyi compat_sys_s390_sthyi
381 common kexec_file_load sys_kexec_file_load compat_sys_kexec_file_load
+382 common io_pgetevents sys_io_pgetevents compat_sys_io_pgetevents
+383 common rseq sys_rseq compat_sys_rseq
diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c
index 84bd632..e3bd562 100644
--- a/arch/s390/mm/pgalloc.c
+++ b/arch/s390/mm/pgalloc.c
@@ -252,6 +252,8 @@ void page_table_free(struct mm_struct *mm, unsigned long *table)
spin_unlock_bh(&mm->context.lock);
if (mask != 0)
return;
+ } else {
+ atomic_xor_bits(&page->_refcount, 3U << 24);
}
pgtable_page_dtor(page);
@@ -304,6 +306,8 @@ static void __tlb_remove_table(void *_table)
break;
/* fallthrough */
case 3: /* 4K page table with pgstes */
+ if (mask & 3)
+ atomic_xor_bits(&page->_refcount, 3 << 24);
pgtable_page_dtor(page);
__free_page(page);
break;
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index d3a38c4..a9f60d0 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -41,6 +41,15 @@
#define DASD_DIAG_MOD "dasd_diag_mod"
+static unsigned int queue_depth = 32;
+static unsigned int nr_hw_queues = 4;
+
+module_param(queue_depth, uint, 0444);
+MODULE_PARM_DESC(queue_depth, "Default queue depth for new DASD devices");
+
+module_param(nr_hw_queues, uint, 0444);
+MODULE_PARM_DESC(nr_hw_queues, "Default number of hardware queues for new DASD devices");
+
/*
* SECTION: exported variables of dasd.c
*/
@@ -3115,8 +3124,8 @@ static int dasd_alloc_queue(struct dasd_block *block)
block->tag_set.ops = &dasd_mq_ops;
block->tag_set.cmd_size = sizeof(struct dasd_ccw_req);
- block->tag_set.nr_hw_queues = DASD_NR_HW_QUEUES;
- block->tag_set.queue_depth = DASD_MAX_LCU_DEV * DASD_REQ_PER_DEV;
+ block->tag_set.nr_hw_queues = nr_hw_queues;
+ block->tag_set.queue_depth = queue_depth;
block->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
rc = blk_mq_alloc_tag_set(&block->tag_set);
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index 976b6bd..de6b960 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -228,14 +228,6 @@ struct dasd_ccw_req {
#define DASD_CQR_SUPPRESS_IL 6 /* Suppress 'Incorrect Length' error */
#define DASD_CQR_SUPPRESS_CR 7 /* Suppress 'Command Reject' error */
-/*
- * There is no reliable way to determine the number of available CPUs on
- * LPAR but there is no big performance difference between 1 and the
- * maximum CPU number.
- * 64 is a good trade off performance wise.
- */
-#define DASD_NR_HW_QUEUES 64
-#define DASD_MAX_LCU_DEV 256
#define DASD_REQ_PER_DEV 4
/* Signature for error recovery functions. */