Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail.openrapids.net ([64.15.138.104]:59953 "EHLO blackscsi.openrapids.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754075Ab2J3TUb (ORCPT ); Tue, 30 Oct 2012 15:20:31 -0400 Date: Tue, 30 Oct 2012 15:20:28 -0400 From: Mathieu Desnoyers To: Sasha Levin Cc: torvalds@linux-foundation.org, tj@kernel.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, paul.gortmaker@windriver.com, davem@davemloft.net, rostedt@goodmis.org, mingo@elte.hu, ebiederm@xmission.com, aarcange@redhat.com, ericvh@gmail.com, netdev@vger.kernel.org, josh@joshtriplett.org, eric.dumazet@gmail.com, axboe@kernel.dk, agk@redhat.com, dm-devel@redhat.com, neilb@suse.de, ccaulfie@redhat.com, teigland@redhat.com, Trond.Myklebust@netapp.com, bfields@fieldses.org, fweisbec@gmail.com, jesse@nicira.com, venkat.x.venkatsubra@oracle.com, ejt@redhat.com, snitzer@redhat.com, edumazet@google.com, linux-nfs@vger.kernel.org, dev@openvswitch.org, rds-devel@oss.oracle.com, lw@cn.fujitsu.com Subject: Re: [PATCH v8 06/16] tracepoint: use new hashtable implementation Message-ID: <20121030192028.GC9427@Krystal> References: <1351622772-16400-1-git-send-email-levinsasha928@gmail.com> <1351622772-16400-6-git-send-email-levinsasha928@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1351622772-16400-6-git-send-email-levinsasha928@gmail.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: * Sasha Levin (levinsasha928@gmail.com) wrote: > Switch tracepoints to use the new hashtable implementation. This reduces the > amount of generic unrelated code in the tracepoints. > > Signed-off-by: Sasha Levin Reviewed-by: Mathieu Desnoyers > --- > kernel/tracepoint.c | 25 +++++++++---------------- > 1 file changed, 9 insertions(+), 16 deletions(-) > > diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c > index d96ba22..5b599f1 100644 > --- a/kernel/tracepoint.c > +++ b/kernel/tracepoint.c > @@ -26,6 +26,7 @@ > #include > #include > #include > +#include > > extern struct tracepoint * const __start___tracepoints_ptrs[]; > extern struct tracepoint * const __stop___tracepoints_ptrs[]; > @@ -49,8 +50,7 @@ static LIST_HEAD(tracepoint_module_list); > * Protected by tracepoints_mutex. > */ > #define TRACEPOINT_HASH_BITS 6 > -#define TRACEPOINT_TABLE_SIZE (1 << TRACEPOINT_HASH_BITS) > -static struct hlist_head tracepoint_table[TRACEPOINT_TABLE_SIZE]; > +static DEFINE_HASHTABLE(tracepoint_table, TRACEPOINT_HASH_BITS); > > /* > * Note about RCU : > @@ -191,16 +191,15 @@ tracepoint_entry_remove_probe(struct tracepoint_entry *entry, > */ > static struct tracepoint_entry *get_tracepoint(const char *name) > { > - struct hlist_head *head; > struct hlist_node *node; > struct tracepoint_entry *e; > u32 hash = jhash(name, strlen(name), 0); > > - head = &tracepoint_table[hash & (TRACEPOINT_TABLE_SIZE - 1)]; > - hlist_for_each_entry(e, node, head, hlist) { > + hash_for_each_possible(tracepoint_table, e, node, hlist, hash) { > if (!strcmp(name, e->name)) > return e; > } > + > return NULL; > } > > @@ -210,19 +209,13 @@ static struct tracepoint_entry *get_tracepoint(const char *name) > */ > static struct tracepoint_entry *add_tracepoint(const char *name) > { > - struct hlist_head *head; > - struct hlist_node *node; > struct tracepoint_entry *e; > size_t name_len = strlen(name) + 1; > u32 hash = jhash(name, name_len-1, 0); > > - head = &tracepoint_table[hash & (TRACEPOINT_TABLE_SIZE - 1)]; > - hlist_for_each_entry(e, node, head, hlist) { > - if (!strcmp(name, e->name)) { > - printk(KERN_NOTICE > - "tracepoint %s busy\n", name); > - return ERR_PTR(-EEXIST); /* Already there */ > - } > + if (get_tracepoint(name)) { > + printk(KERN_NOTICE "tracepoint %s busy\n", name); > + return ERR_PTR(-EEXIST); /* Already there */ > } > /* > * Using kmalloc here to allocate a variable length element. Could > @@ -234,7 +227,7 @@ static struct tracepoint_entry *add_tracepoint(const char *name) > memcpy(&e->name[0], name, name_len); > e->funcs = NULL; > e->refcount = 0; > - hlist_add_head(&e->hlist, head); > + hash_add(tracepoint_table, &e->hlist, hash); > return e; > } > > @@ -244,7 +237,7 @@ static struct tracepoint_entry *add_tracepoint(const char *name) > */ > static inline void remove_tracepoint(struct tracepoint_entry *e) > { > - hlist_del(&e->hlist); > + hash_del(&e->hlist); > kfree(e); > } > > -- > 1.7.12.4 > -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com