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ANDROID: rwsem: Add vendor hook to the rw-semaphore

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- Add the hook to apply vendor's performance tune for owner
    of rwsem.

  - Add the hook for the waiter list of rwsem to allow
    vendor perform waiting queue enhancement

  - ANDROID_VENDOR_DATA added to rw_semaphore

Bug: 161400830

Signed-off-by: JianMin Liu <jian-min.liu@mediatek.com>
Change-Id: I007a5e26f3db2adaeaf4e5ccea414ce7abfa83b8
This commit is contained in:
JianMin Liu
2020-07-21 13:36:22 +08:00
committed by Todd Kjos
parent 3fc5e94255
commit df18d99dab
4 changed files with 63 additions and 2 deletions
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20
kernel/locking/rwsem.c
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@@ -29,6 +29,7 @@
#include <linux/atomic.h>
#include "lock_events.h"
#include <trace/hooks/rwsem.h>
/*
* The least significant 3 bits of the owner value has the following
@@ -340,6 +341,7 @@ void __init_rwsem(struct rw_semaphore *sem, const char *name,
#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
osq_lock_init(&sem->osq);
#endif
trace_android_vh_rwsem_init(sem);
}
EXPORT_SYMBOL(__init_rwsem);
@@ -995,6 +997,7 @@ rwsem_down_read_slowpath(struct rw_semaphore *sem, int state)
struct rwsem_waiter waiter;
DEFINE_WAKE_Q(wake_q);
bool wake = false;
bool already_on_list = false;
/*
* Save the current read-owner of rwsem, if available, and the
@@ -1056,7 +1059,11 @@ queue:
}
adjustment += RWSEM_FLAG_WAITERS;
}
list_add_tail(&waiter.list, &sem->wait_list);
trace_android_vh_alter_rwsem_list_add(
&waiter,
sem, &already_on_list);
if (!already_on_list)
list_add_tail(&waiter.list, &sem->wait_list);
/* we're now waiting on the lock, but no longer actively locking */
if (adjustment)
@@ -1078,6 +1085,7 @@ queue:
(adjustment & RWSEM_FLAG_WAITERS)))
rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q);
trace_android_vh_rwsem_wake(sem);
raw_spin_unlock_irq(&sem->wait_lock);
wake_up_q(&wake_q);
@@ -1141,6 +1149,7 @@ rwsem_down_write_slowpath(struct rw_semaphore *sem, int state)
struct rwsem_waiter waiter;
struct rw_semaphore *ret = sem;
DEFINE_WAKE_Q(wake_q);
bool already_on_list = false;
/* do optimistic spinning and steal lock if possible */
if (rwsem_can_spin_on_owner(sem, RWSEM_WR_NONSPINNABLE) &&
@@ -1169,7 +1178,11 @@ rwsem_down_write_slowpath(struct rw_semaphore *sem, int state)
/* account for this before adding a new element to the list */
wstate = list_empty(&sem->wait_list) ? WRITER_FIRST : WRITER_NOT_FIRST;
list_add_tail(&waiter.list, &sem->wait_list);
trace_android_vh_alter_rwsem_list_add(
&waiter,
sem, &already_on_list);
if (!already_on_list)
list_add_tail(&waiter.list, &sem->wait_list);
/* we're now waiting on the lock */
if (wstate == WRITER_NOT_FIRST) {
@@ -1205,6 +1218,7 @@ rwsem_down_write_slowpath(struct rw_semaphore *sem, int state)
}
wait:
trace_android_vh_rwsem_wake(sem);
/* wait until we successfully acquire the lock */
set_current_state(state);
for (;;) {
@@ -1581,6 +1595,7 @@ EXPORT_SYMBOL(up_read);
void up_write(struct rw_semaphore *sem)
{
rwsem_release(&sem->dep_map, _RET_IP_);
trace_android_vh_rwsem_write_finished(sem);
__up_write(sem);
}
EXPORT_SYMBOL(up_write);
@@ -1591,6 +1606,7 @@ EXPORT_SYMBOL(up_write);
void downgrade_write(struct rw_semaphore *sem)
{
lock_downgrade(&sem->dep_map, _RET_IP_);
trace_android_vh_rwsem_write_finished(sem);
__downgrade_write(sem);
}
EXPORT_SYMBOL(downgrade_write);