From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx107.postini.com [74.125.245.107]) by kanga.kvack.org (Postfix) with SMTP id 3C2E36B0075 for ; Sat, 4 Aug 2012 20:36:38 -0400 (EDT) Message-ID: <1344126994.27983.116.camel@gandalf.stny.rr.com> Subject: Re: [RFC v2 6/7] tracepoint: use new hashtable implementation From: Steven Rostedt Date: Sat, 04 Aug 2012 20:36:34 -0400 In-Reply-To: <1344003788-1417-7-git-send-email-levinsasha928@gmail.com> References: <1344003788-1417-1-git-send-email-levinsasha928@gmail.com> <1344003788-1417-7-git-send-email-levinsasha928@gmail.com> Content-Type: text/plain; charset="ISO-8859-15" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: 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, mingo@elte.hu, ebiederm@xmission.com, aarcange@redhat.com, ericvh@gmail.com, netdev@vger.kernel.org, Mathieu Desnoyers FYI, Mathieu is the author of this file. -- Steve On Fri, 2012-08-03 at 16:23 +0200, Sasha Levin 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 > --- > kernel/tracepoint.c | 26 +++++++++----------------- > 1 files changed, 9 insertions(+), 17 deletions(-) > > diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c > index d96ba22..b5a2650 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]; > +DEFINE_STATIC_HASHTABLE(tracepoint_table, TRACEPOINT_HASH_BITS); > > /* > * Note about RCU : > @@ -191,16 +191,14 @@ 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, node, e, hlist, hash) > if (!strcmp(name, e->name)) > return e; > - } > + > return NULL; > } > > @@ -210,19 +208,13 @@ 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 +226,7 @@ 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 +236,7 @@ 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); > } > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org