[tip:perf/urgent] perf: Don't use -ENOSPC for out of PMU resources

From: tip-bot for Peter Zijlstra
Date: Fri Nov 18 2011 - 18:34:20 EST


Commit-ID: aa2bc1ade59003a379ffc485d6da2d92ea3370a6
Gitweb: http://git.kernel.org/tip/aa2bc1ade59003a379ffc485d6da2d92ea3370a6
Author: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
AuthorDate: Wed, 9 Nov 2011 17:56:37 +0100
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Mon, 14 Nov 2011 13:01:24 +0100

perf: Don't use -ENOSPC for out of PMU resources

People (Linus) objected to using -ENOSPC to signal not having enough
resources on the PMU to satisfy the request. Use -EINVAL.

Requested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: Deng-Cheng Zhu <dengcheng.zhu@xxxxxxxxx>
Cc: David Daney <david.daney@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-xv8geaz2zpbjhlx0svmpp28n@xxxxxxxxxxxxxx
[ merged to newer kernel, fixed up MIPS impact ]
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
---
arch/arm/kernel/perf_event.c | 6 +++---
arch/mips/kernel/perf_event_mipsxx.c | 8 ++++----
arch/x86/kernel/cpu/perf_event.c | 10 +++++-----
arch/x86/kernel/cpu/perf_event_p4.c | 2 +-
4 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 24e2347..ff17b17 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -347,15 +347,15 @@ validate_group(struct perf_event *event)
memset(&fake_pmu, 0, sizeof(fake_pmu));

if (!validate_event(&fake_pmu, leader))
- return -ENOSPC;
+ return -EINVAL;

list_for_each_entry(sibling, &leader->sibling_list, group_entry) {
if (!validate_event(&fake_pmu, sibling))
- return -ENOSPC;
+ return -EINVAL;
}

if (!validate_event(&fake_pmu, event))
- return -ENOSPC;
+ return -EINVAL;

return 0;
}
diff --git a/arch/mips/kernel/perf_event_mipsxx.c b/arch/mips/kernel/perf_event_mipsxx.c
index 4f2971b..315fc0b 100644
--- a/arch/mips/kernel/perf_event_mipsxx.c
+++ b/arch/mips/kernel/perf_event_mipsxx.c
@@ -623,7 +623,7 @@ static int mipspmu_event_init(struct perf_event *event)
if (!atomic_inc_not_zero(&active_events)) {
if (atomic_read(&active_events) > MIPS_MAX_HWEVENTS) {
atomic_dec(&active_events);
- return -ENOSPC;
+ return -EINVAL;
}

mutex_lock(&pmu_reserve_mutex);
@@ -732,15 +732,15 @@ static int validate_group(struct perf_event *event)
memset(&fake_cpuc, 0, sizeof(fake_cpuc));

if (!validate_event(&fake_cpuc, leader))
- return -ENOSPC;
+ return -EINVAL;

list_for_each_entry(sibling, &leader->sibling_list, group_entry) {
if (!validate_event(&fake_cpuc, sibling))
- return -ENOSPC;
+ return -EINVAL;
}

if (!validate_event(&fake_cpuc, event))
- return -ENOSPC;
+ return -EINVAL;

return 0;
}
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 6408910..ff0e8d4 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -588,7 +588,7 @@ done:
x86_pmu.put_event_constraints(cpuc, cpuc->event_list[i]);
}
}
- return num ? -ENOSPC : 0;
+ return num ? -EINVAL : 0;
}

/*
@@ -607,7 +607,7 @@ static int collect_events(struct cpu_hw_events *cpuc, struct perf_event *leader,

if (is_x86_event(leader)) {
if (n >= max_count)
- return -ENOSPC;
+ return -EINVAL;
cpuc->event_list[n] = leader;
n++;
}
@@ -620,7 +620,7 @@ static int collect_events(struct cpu_hw_events *cpuc, struct perf_event *leader,
continue;

if (n >= max_count)
- return -ENOSPC;
+ return -EINVAL;

cpuc->event_list[n] = event;
n++;
@@ -1316,7 +1316,7 @@ static int validate_event(struct perf_event *event)
c = x86_pmu.get_event_constraints(fake_cpuc, event);

if (!c || !c->weight)
- ret = -ENOSPC;
+ ret = -EINVAL;

if (x86_pmu.put_event_constraints)
x86_pmu.put_event_constraints(fake_cpuc, event);
@@ -1341,7 +1341,7 @@ static int validate_group(struct perf_event *event)
{
struct perf_event *leader = event->group_leader;
struct cpu_hw_events *fake_cpuc;
- int ret = -ENOSPC, n;
+ int ret = -EINVAL, n;

fake_cpuc = allocate_fake_cpuc();
if (IS_ERR(fake_cpuc))
diff --git a/arch/x86/kernel/cpu/perf_event_p4.c b/arch/x86/kernel/cpu/perf_event_p4.c
index 492bf13..ef484d9 100644
--- a/arch/x86/kernel/cpu/perf_event_p4.c
+++ b/arch/x86/kernel/cpu/perf_event_p4.c
@@ -1268,7 +1268,7 @@ reserve:
}

done:
- return num ? -ENOSPC : 0;
+ return num ? -EINVAL : 0;
}

static __initconst const struct x86_pmu p4_pmu = {
--
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