Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753996Ab0AYPT4 (ORCPT ); Mon, 25 Jan 2010 10:19:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753913Ab0AYPTN (ORCPT ); Mon, 25 Jan 2010 10:19:13 -0500 Received: from hera.kernel.org ([140.211.167.34]:42986 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753848Ab0AYPTL (ORCPT ); Mon, 25 Jan 2010 10:19:11 -0500 From: Tejun Heo To: linux-kernel@vger.kernel.org, axboe@kernel.dk, rusty@rustcorp.com.au, akpm@linux-foundation.org, ebiederm@xmission.com, tytso@mit.edu, Trond.Myklebust@netapp.com, aelder@sgi.com, hch@infradead.org, viro@zeniv.linux.org.uk, davem@davemloft.net, netdev@vger.kernel.org, x86@kernel.org, mingo@redhat.com, fweisbec@gmail.com, dan.j.williams@intel.com, borislav.petkov@amd.com, ying.huang@intel.com, lenb@kernel.org, neilb@suse.de, cl@linux-foundation.org Cc: Tejun Heo Subject: [PATCH 7/8] percpu: add __percpu sparse annotations to hw_breakpoint Date: Tue, 26 Jan 2010 00:22:14 +0900 Message-Id: <1264432935-10453-8-git-send-email-tj@kernel.org> X-Mailer: git-send-email 1.6.4.2 In-Reply-To: <1264432935-10453-1-git-send-email-tj@kernel.org> References: <1264432935-10453-1-git-send-email-tj@kernel.org> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Mon, 25 Jan 2010 15:17:48 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5716 Lines: 151 Add __percpu sparse annotations to hw_breakpoint. These annotations are to make sparse consider percpu variables to be in a different address space and warn if accessed without going through percpu accessors. This patch doesn't affect normal builds. per_cpu(nr_task_bp_pinned, cpu) is replaced with &per_cpu(nr_task_bp_pinned[0], cpu). This is the same to the compiler but allows per_cpu() macro to correctly drop __percpu designation for the returned pointer. Signed-off-by: Tejun Heo Cc: Frederic Weisbecker --- include/linux/hw_breakpoint.h | 8 ++++---- kernel/hw_breakpoint.c | 14 +++++++------- samples/hw_breakpoint/data_breakpoint.c | 6 +++--- 3 files changed, 14 insertions(+), 14 deletions(-) diff --git a/include/linux/hw_breakpoint.h b/include/linux/hw_breakpoint.h index 41235c9..f462d3d 100644 --- a/include/linux/hw_breakpoint.h +++ b/include/linux/hw_breakpoint.h @@ -66,14 +66,14 @@ register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr, perf_overflow_handler_t triggered, int cpu); -extern struct perf_event ** +extern struct perf_event * __percpu * register_wide_hw_breakpoint(struct perf_event_attr *attr, perf_overflow_handler_t triggered); extern int register_perf_hw_breakpoint(struct perf_event *bp); extern int __register_perf_hw_breakpoint(struct perf_event *bp); extern void unregister_hw_breakpoint(struct perf_event *bp); -extern void unregister_wide_hw_breakpoint(struct perf_event **cpu_events); +extern void unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events); extern int reserve_bp_slot(struct perf_event *bp); extern void release_bp_slot(struct perf_event *bp); @@ -98,7 +98,7 @@ static inline struct perf_event * register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr, perf_overflow_handler_t triggered, int cpu) { return NULL; } -static inline struct perf_event ** +static inline struct perf_event * __percpu * register_wide_hw_breakpoint(struct perf_event_attr *attr, perf_overflow_handler_t triggered) { return NULL; } static inline int @@ -107,7 +107,7 @@ static inline int __register_perf_hw_breakpoint(struct perf_event *bp) { return -ENOSYS; } static inline void unregister_hw_breakpoint(struct perf_event *bp) { } static inline void -unregister_wide_hw_breakpoint(struct perf_event **cpu_events) { } +unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events) { } static inline int reserve_bp_slot(struct perf_event *bp) {return -ENOSYS; } static inline void release_bp_slot(struct perf_event *bp) { } diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c index 50dbd59..11dae6d 100644 --- a/kernel/hw_breakpoint.c +++ b/kernel/hw_breakpoint.c @@ -74,7 +74,7 @@ static DEFINE_MUTEX(nr_bp_mutex); static unsigned int max_task_bp_pinned(int cpu) { int i; - unsigned int *tsk_pinned = per_cpu(nr_task_bp_pinned, cpu); + unsigned int *tsk_pinned = &per_cpu(nr_task_bp_pinned[0], cpu); for (i = HBP_NUM -1; i >= 0; i--) { if (tsk_pinned[i] > 0) @@ -163,7 +163,7 @@ static void toggle_bp_task_slot(struct task_struct *tsk, int cpu, bool enable) count = task_bp_pinned(tsk); - tsk_pinned = per_cpu(nr_task_bp_pinned, cpu); + tsk_pinned = &per_cpu(nr_task_bp_pinned[0], cpu); if (enable) { tsk_pinned[count]++; if (count > 0) @@ -377,17 +377,17 @@ EXPORT_SYMBOL_GPL(unregister_hw_breakpoint); * * @return a set of per_cpu pointers to perf events */ -struct perf_event ** +struct perf_event * __percpu * register_wide_hw_breakpoint(struct perf_event_attr *attr, perf_overflow_handler_t triggered) { - struct perf_event **cpu_events, **pevent, *bp; + struct perf_event * __percpu *cpu_events, **pevent, *bp; long err; int cpu; cpu_events = alloc_percpu(typeof(*cpu_events)); if (!cpu_events) - return ERR_PTR(-ENOMEM); + return (void __percpu __force *)ERR_PTR(-ENOMEM); get_online_cpus(); for_each_online_cpu(cpu) { @@ -415,7 +415,7 @@ fail: put_online_cpus(); free_percpu(cpu_events); - return ERR_PTR(err); + return (void __percpu __force *)ERR_PTR(err); } EXPORT_SYMBOL_GPL(register_wide_hw_breakpoint); @@ -423,7 +423,7 @@ EXPORT_SYMBOL_GPL(register_wide_hw_breakpoint); * unregister_wide_hw_breakpoint - unregister a wide breakpoint in the kernel * @cpu_events: the per cpu set of events to unregister */ -void unregister_wide_hw_breakpoint(struct perf_event **cpu_events) +void unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events) { int cpu; struct perf_event **pevent; diff --git a/samples/hw_breakpoint/data_breakpoint.c b/samples/hw_breakpoint/data_breakpoint.c index c69cbe9..bd0f337 100644 --- a/samples/hw_breakpoint/data_breakpoint.c +++ b/samples/hw_breakpoint/data_breakpoint.c @@ -34,7 +34,7 @@ #include #include -struct perf_event **sample_hbp; +struct perf_event * __percpu *sample_hbp; static char ksym_name[KSYM_NAME_LEN] = "pid_max"; module_param_string(ksym, ksym_name, KSYM_NAME_LEN, S_IRUGO); @@ -61,8 +61,8 @@ static int __init hw_break_module_init(void) attr.bp_type = HW_BREAKPOINT_W | HW_BREAKPOINT_R; sample_hbp = register_wide_hw_breakpoint(&attr, sample_hbp_handler); - if (IS_ERR(sample_hbp)) { - ret = PTR_ERR(sample_hbp); + if (IS_ERR((void __force *)sample_hbp)) { + ret = PTR_ERR((void __force *)sample_hbp); goto fail; } -- 1.6.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/