diff options
Diffstat (limited to 'kernel/marker.c')
-rw-r--r-- | kernel/marker.c | 19 |
1 files changed, 8 insertions, 11 deletions
diff --git a/kernel/marker.c b/kernel/marker.c index 48a4ea5afffd..ccae1d10e32f 100644 --- a/kernel/marker.c +++ b/kernel/marker.c | |||
@@ -104,9 +104,9 @@ void marker_probe_cb(const struct marker *mdata, void *call_private, | |||
104 | char ptype; | 104 | char ptype; |
105 | 105 | ||
106 | /* | 106 | /* |
107 | * disabling preemption to make sure the teardown of the callbacks can | 107 | * preempt_disable does two things : disabling preemption to make sure |
108 | * be done correctly when they are in modules and they insure RCU read | 108 | * the teardown of the callbacks can be done correctly when they are in |
109 | * coherency. | 109 | * modules and they insure RCU read coherency. |
110 | */ | 110 | */ |
111 | preempt_disable(); | 111 | preempt_disable(); |
112 | ptype = ACCESS_ONCE(mdata->ptype); | 112 | ptype = ACCESS_ONCE(mdata->ptype); |
@@ -551,9 +551,9 @@ static int set_marker(struct marker_entry **entry, struct marker *elem, | |||
551 | 551 | ||
552 | /* | 552 | /* |
553 | * Disable a marker and its probe callback. | 553 | * Disable a marker and its probe callback. |
554 | * Note: only after a synchronize_sched() issued after setting elem->call to the | 554 | * Note: only waiting an RCU period after setting elem->call to the empty |
555 | * empty function insures that the original callback is not used anymore. This | 555 | * function insures that the original callback is not used anymore. This insured |
556 | * insured by preemption disabling around the call site. | 556 | * by preempt_disable around the call site. |
557 | */ | 557 | */ |
558 | static void disable_marker(struct marker *elem) | 558 | static void disable_marker(struct marker *elem) |
559 | { | 559 | { |
@@ -565,8 +565,8 @@ static void disable_marker(struct marker *elem) | |||
565 | elem->ptype = 0; /* single probe */ | 565 | elem->ptype = 0; /* single probe */ |
566 | /* | 566 | /* |
567 | * Leave the private data and id there, because removal is racy and | 567 | * Leave the private data and id there, because removal is racy and |
568 | * should be done only after a synchronize_sched(). These are never used | 568 | * should be done only after an RCU period. These are never used until |
569 | * until the next initialization anyway. | 569 | * the next initialization anyway. |
570 | */ | 570 | */ |
571 | } | 571 | } |
572 | 572 | ||
@@ -601,9 +601,6 @@ void marker_update_probe_range(struct marker *begin, | |||
601 | 601 | ||
602 | /* | 602 | /* |
603 | * Update probes, removing the faulty probes. | 603 | * Update probes, removing the faulty probes. |
604 | * Issues a synchronize_sched() when no reference to the module passed | ||
605 | * as parameter is found in the probes so the probe module can be | ||
606 | * safely unloaded from now on. | ||
607 | * | 604 | * |
608 | * Internal callback only changed before the first probe is connected to it. | 605 | * Internal callback only changed before the first probe is connected to it. |
609 | * Single probe private data can only be changed on 0 -> 1 and 2 -> 1 | 606 | * Single probe private data can only be changed on 0 -> 1 and 2 -> 1 |