From 9cb37357dfce1b596041ad68a20407c8b4e76635 Mon Sep 17 00:00:00 2001 From: Zhen Lei Date: Wed, 2 Nov 2022 16:49:18 +0800 Subject: livepatch: Use kallsyms_on_each_match_symbol() to improve performance Based on the test results of kallsyms_on_each_match_symbol() and kallsyms_on_each_symbol(), the average performance can be improved by more than 1500 times. Signed-off-by: Zhen Lei Signed-off-by: Luis Chamberlain --- kernel/livepatch/core.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) (limited to 'kernel/livepatch') diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 9ada0bc5247b..50bfc3481a4e 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -153,6 +153,24 @@ static int klp_find_callback(void *data, const char *name, return 0; } +static int klp_match_callback(void *data, unsigned long addr) +{ + struct klp_find_arg *args = data; + + args->addr = addr; + args->count++; + + /* + * Finish the search when the symbol is found for the desired position + * or the position is not defined for a non-unique symbol. + */ + if ((args->pos && (args->count == args->pos)) || + (!args->pos && (args->count > 1))) + return 1; + + return 0; +} + static int klp_find_object_symbol(const char *objname, const char *name, unsigned long sympos, unsigned long *addr) { @@ -167,7 +185,7 @@ static int klp_find_object_symbol(const char *objname, const char *name, if (objname) module_kallsyms_on_each_symbol(klp_find_callback, &args); else - kallsyms_on_each_symbol(klp_find_callback, &args); + kallsyms_on_each_match_symbol(klp_match_callback, name, &args); /* * Ensure an address was found. If sympos is 0, ensure symbol is unique; -- cgit v1.2.3-59-g8ed1b From 4f1354d5c6a3264c91238962d1597eef40c40419 Mon Sep 17 00:00:00 2001 From: Zhen Lei Date: Wed, 7 Dec 2022 11:23:04 +0800 Subject: livepatch: Call klp_match_callback() in klp_find_callback() to avoid code duplication The implementation of function klp_match_callback() is identical to the partial implementation of function klp_find_callback(). So call function klp_match_callback() in function klp_find_callback() instead of the duplicated code. Signed-off-by: Zhen Lei Acked-by: Song Liu Reviewed-by: Petr Mladek Suggested-by: Petr Mladek Signed-off-by: Luis Chamberlain --- kernel/livepatch/core.c | 33 +++++++++++---------------------- 1 file changed, 11 insertions(+), 22 deletions(-) (limited to 'kernel/livepatch') diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 50bfc3481a4e..201f0c0482fb 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -125,20 +125,10 @@ struct klp_find_arg { unsigned long pos; }; -static int klp_find_callback(void *data, const char *name, - struct module *mod, unsigned long addr) +static int klp_match_callback(void *data, unsigned long addr) { struct klp_find_arg *args = data; - if ((mod && !args->objname) || (!mod && args->objname)) - return 0; - - if (strcmp(args->name, name)) - return 0; - - if (args->objname && strcmp(args->objname, mod->name)) - return 0; - args->addr = addr; args->count++; @@ -153,22 +143,21 @@ static int klp_find_callback(void *data, const char *name, return 0; } -static int klp_match_callback(void *data, unsigned long addr) +static int klp_find_callback(void *data, const char *name, + struct module *mod, unsigned long addr) { struct klp_find_arg *args = data; - args->addr = addr; - args->count++; + if ((mod && !args->objname) || (!mod && args->objname)) + return 0; - /* - * Finish the search when the symbol is found for the desired position - * or the position is not defined for a non-unique symbol. - */ - if ((args->pos && (args->count == args->pos)) || - (!args->pos && (args->count > 1))) - return 1; + if (strcmp(args->name, name)) + return 0; - return 0; + if (args->objname && strcmp(args->objname, mod->name)) + return 0; + + return klp_match_callback(data, addr); } static int klp_find_object_symbol(const char *objname, const char *name, -- cgit v1.2.3-59-g8ed1b