projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| 2381c1ce GKH |
1 | From f67b15037a7a50c57f72e69a6d59941ad90a0f0f Mon Sep 17 00:00:00 2001 |
| 2 | From: Linus Torvalds <torvalds@linux-foundation.org> | |
| 3 | Date: Mon, 26 Mar 2018 15:39:07 -1000 | |
| 4 | Subject: perf/hwbp: Simplify the perf-hwbp code, fix documentation | |
| 5 | ||
| 6 | From: Linus Torvalds <torvalds@linux-foundation.org> | |
| 7 | ||
| 8 | commit f67b15037a7a50c57f72e69a6d59941ad90a0f0f upstream. | |
| 9 | ||
| 10 | Annoyingly, modify_user_hw_breakpoint() unnecessarily complicates the | |
| 11 | modification of a breakpoint - simplify it and remove the pointless | |
| 12 | local variables. | |
| 13 | ||
| 14 | Also update the stale Docbook while at it. | |
| 15 | ||
| 16 | Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> | |
| 17 | Acked-by: Thomas Gleixner <tglx@linutronix.de> | |
| 18 | Cc: <stable@vger.kernel.org> | |
| 19 | Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> | |
| 20 | Cc: Andy Lutomirski <luto@kernel.org> | |
| 21 | Cc: Arnaldo Carvalho de Melo <acme@redhat.com> | |
| 22 | Cc: Frederic Weisbecker <fweisbec@gmail.com> | |
| 23 | Cc: Jiri Olsa <jolsa@redhat.com> | |
| 24 | Cc: Peter Zijlstra <peterz@infradead.org> | |
| 25 | Cc: Stephane Eranian <eranian@google.com> | |
| 26 | Cc: Vince Weaver <vincent.weaver@maine.edu> | |
| 27 | Signed-off-by: Ingo Molnar <mingo@kernel.org> | |
| 28 | Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| 29 | ||
| 30 | --- | |
| 31 | kernel/events/hw_breakpoint.c | 30 +++++++----------------------- | |
| 32 | 1 file changed, 7 insertions(+), 23 deletions(-) | |
| 33 | ||
| 34 | --- a/kernel/events/hw_breakpoint.c | |
| 35 | +++ b/kernel/events/hw_breakpoint.c | |
| 36 | @@ -427,16 +427,9 @@ EXPORT_SYMBOL_GPL(register_user_hw_break | |
| 37 | * modify_user_hw_breakpoint - modify a user-space hardware breakpoint | |
| 38 | * @bp: the breakpoint structure to modify | |
| 39 | * @attr: new breakpoint attributes | |
| 40 | - * @triggered: callback to trigger when we hit the breakpoint | |
| 41 | - * @tsk: pointer to 'task_struct' of the process to which the address belongs | |
| 42 | */ | |
| 43 | int modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *attr) | |
| 44 | { | |
| 45 | - u64 old_addr = bp->attr.bp_addr; | |
| 46 | - u64 old_len = bp->attr.bp_len; | |
| 47 | - int old_type = bp->attr.bp_type; | |
| 48 | - int err = 0; | |
| 49 | - | |
| 50 | /* | |
| 51 | * modify_user_hw_breakpoint can be invoked with IRQs disabled and hence it | |
| 52 | * will not be possible to raise IPIs that invoke __perf_event_disable. | |
| 53 | @@ -451,27 +444,18 @@ int modify_user_hw_breakpoint(struct per | |
| 54 | bp->attr.bp_addr = attr->bp_addr; | |
| 55 | bp->attr.bp_type = attr->bp_type; | |
| 56 | bp->attr.bp_len = attr->bp_len; | |
| 57 | + bp->attr.disabled = 1; | |
| 58 | ||
| 59 | - if (attr->disabled) | |
| 60 | - goto end; | |
| 61 | - | |
| 62 | - err = validate_hw_breakpoint(bp); | |
| 63 | - if (!err) | |
| 64 | - perf_event_enable(bp); | |
| 65 | + if (!attr->disabled) { | |
| 66 | + int err = validate_hw_breakpoint(bp); | |
| 67 | ||
| 68 | - if (err) { | |
| 69 | - bp->attr.bp_addr = old_addr; | |
| 70 | - bp->attr.bp_type = old_type; | |
| 71 | - bp->attr.bp_len = old_len; | |
| 72 | - if (!bp->attr.disabled) | |
| 73 | - perf_event_enable(bp); | |
| 74 | + if (err) | |
| 75 | + return err; | |
| 76 | ||
| 77 | - return err; | |
| 78 | + perf_event_enable(bp); | |
| 79 | + bp->attr.disabled = 0; | |
| 80 | } | |
| 81 | ||
| 82 | -end: | |
| 83 | - bp->attr.disabled = attr->disabled; | |
| 84 | - | |
| 85 | return 0; | |
| 86 | } | |
| 87 | EXPORT_SYMBOL_GPL(modify_user_hw_breakpoint); |