[RFC,v2,5/7] readahead: create the configuration file

Message ID	20220311190617.3294919-6-tbecker@redhat.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <linux-nfs-owner@kernel.org> From: Thiago Becker <tbecker@redhat.com> To: linux-nfs@vger.kernel.org Cc: steved@redhat.com, trond.myklebust@hammerspace.com, anna.schumaker@netapp.com, kolga@netapp.com, Thiago Becker <tbecker@redhat.com> Subject: [RFC v2 PATCH 5/7] readahead: create the configuration file Date: Fri, 11 Mar 2022 16:06:15 -0300 Message-Id: <20220311190617.3294919-6-tbecker@redhat.com> In-Reply-To: <20220311190617.3294919-1-tbecker@redhat.com> References: <20220311190617.3294919-1-tbecker@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	Introduce nfs-readahead-udev \| expand [RFC,v2,0/7] Introduce nfs-readahead-udev [RFC,v2,1/7] Create nfs-readahead-udev [RFC,v2,2/7] readahead: configure udev [RFC,v2,3/7] readahead: create logging facility [RFC,v2,4/7] readahead: only set readahead for nfs devices. [RFC,v2,5/7] readahead: create the configuration file [RFC,v2,6/7] readahead: add mountpoint and fstype options [RFC,v2,7/7] readahead: documentation

diff --git a/.gitignore b/.gitignore index c99269a4..340ee8fb 100644 --- a/.gitignore +++ b/.gitignore @@ -17,6 +17,7 @@ aclocal/ltoptions.m4 aclocal/ltsugar.m4 aclocal/ltversion.m4 aclocal/lt~obsolete.m4 +ylwrap # files generated by configure confdefs.h config.cache @@ -61,7 +62,11 @@ utils/statd/statd tools/locktest/testlk tools/getiversion/getiversion tools/nfsconf/nfsconf +tools/nfs-readahead-udev/99-nfs_bdi.rules tools/nfs-readahead-udev/nfs-readahead-udev +tools/nfs-readahead-udev/parser.c +tools/nfs-readahead-udev/parser.h +tools/nfs-readahead-udev/scanner.c support/export/mount.h support/export/mount_clnt.c support/export/mount_xdr.c diff --git a/configure.ac b/configure.ac index 7e5ba5d9..03cdf8f6 100644 --- a/configure.ac +++ b/configure.ac @@ -300,7 +300,10 @@ AC_PROG_INSTALL AC_PROG_LN_S AC_PROG_MAKE_SET AC_PROG_LIBTOOL +AC_PROG_YACC AM_PROG_CC_C_O +AM_PROG_LEX + if test "x$cross_compiling" = "xno"; then CC_FOR_BUILD=${CC_FOR_BUILD-${CC-gcc}} diff --git a/tools/nfs-readahead-udev/Makefile.am b/tools/nfs-readahead-udev/Makefile.am index 551d22e9..010350aa 100644 --- a/tools/nfs-readahead-udev/Makefile.am +++ b/tools/nfs-readahead-udev/Makefile.am @@ -1,12 +1,24 @@ libexec_PROGRAMS = nfs-readahead-udev -nfs_readahead_udev_SOURCES = main.c syslog.c +BUILT_SOURCES = parser.c parser.h scanner.c +nfs_readahead_udev_SOURCES = main.c syslog.c config_parser.c parser.y scanner.l nfs_readahead_udev_LDFLAGS= -lmount +AM_YFLAGS = -d -udev_rulesdir = /etc/udev/rules.d +udev_rulesdir = $(sysconfdir)/udev/rules.d udev_rules_DATA = 99-nfs_bdi.rules +ra_confdir = $(sysconfdir) +ra_conf_DATA = readahead.conf + 99-nfs_bdi.rules: 99-nfs_bdi.rules.in $(builddefs) $(SED) "s|_libexecdir_|@libexecdir@|g" 99-nfs_bdi.rules.in > $@ clean-local: $(RM) 99-nfs_bdi.rules + $(RM) parser.c parser.h scanner.c + +parser.$(OBJEXT): CFLAGS += -Wno-strict-prototypes + +scanner.$(OBJEXT): CFLAGS += -Wno-strict-prototypes + +main.$(OBJEXT): CFLAGS += -DSYSCONFDIR=\"@sysconfdir@\" diff --git a/tools/nfs-readahead-udev/config_parser.c b/tools/nfs-readahead-udev/config_parser.c new file mode 100644 index 00000000..24d58a6b --- /dev/null +++ b/tools/nfs-readahead-udev/config_parser.c @@ -0,0 +1,25 @@ +#include <stdlib.h> +#include <string.h> +#include "config_parser.h" + +struct config_entry *config_entry_new(void); + +struct config_entry *config_entry_new(void) { + struct config_entry *new = malloc(sizeof(struct config_entry)); + if (!new) { + return NULL; // Make this an err_ptr + } + + memset(new, 0, sizeof(struct config_entry)); + list_init(&new->list); + return new; +} + + +void config_entry_free(struct config_entry *ce) +{ +#define sfree(ce) if (ce) free(ce) + sfree(ce->mountpoint); + sfree(ce->fstype); +#undef sfree +} diff --git a/tools/nfs-readahead-udev/config_parser.h b/tools/nfs-readahead-udev/config_parser.h new file mode 100644 index 00000000..f9f138bb --- /dev/null +++ b/tools/nfs-readahead-udev/config_parser.h @@ -0,0 +1,14 @@ +#ifndef __ra_libparser_h__ +#define __ra_libparser_h__ +#include "list.h" + +struct config_entry { + struct list_head list; + char *mountpoint; + char *fstype; + int readahead; +}; + +extern int parse_config(const char *, struct list_head *config_list); +extern void config_entry_free(struct config_entry *); +#endif diff --git a/tools/nfs-readahead-udev/list.h b/tools/nfs-readahead-udev/list.h new file mode 100644 index 00000000..69239502 --- /dev/null +++ b/tools/nfs-readahead-udev/list.h @@ -0,0 +1,48 @@ +#ifndef __ra_list_h__ +#define __ra_list_h__ +struct list_head +{ + struct list_head *next, *prev; +}; + +static inline void list_init(struct list_head *lh) +{ + lh->next = lh; + lh->prev = lh; +} + +#define LIST_DECLARE(name) \ + struct list_head name; \ + list_init(&name); + +static inline void list_add(struct list_head *l, struct list_head *a) +{ + a->prev = l; + a->next = l->next; + l->next->prev = a; + l->next = a; +} + +static inline void list_del(struct list_head *a) +{ + a->next->prev = a->prev; + a->prev->next = a->next; + a->next = a; + a->prev = a; +} + +#define list_for_each(pos, head) \ + for (pos = (head)->next; pos != (head); pos = pos->next) + +#define list_free(head, free_func) ({ \ + for (struct list_head *__lh = (head)->next; \ + __lh != head; __lh = (head)->next) { \ + list_del(__lh); \ + free_func(__lh); \ + }}) + +#define containerof(p, type, field) ({ \ + const __typeof__(((type *)0)->field) *__ptr = (p); \ + (type *)((char *)__ptr - offsetof(type, field) ); }) + +#endif diff --git a/tools/nfs-readahead-udev/main.c b/tools/nfs-readahead-udev/main.c index bbb408c0..2bd76138 100644 --- a/tools/nfs-readahead-udev/main.c +++ b/tools/nfs-readahead-udev/main.c @@ -2,16 +2,23 @@ #include <string.h> #include <stdlib.h> #include <errno.h> +#include <stddef.h> #include <libmount/libmount.h> #include <sys/sysmacros.h> #include "log.h" +#include "list.h" +#include "config_parser.h" #ifndef MOUNTINFO_PATH #define MOUNTINFO_PATH "/proc/self/mountinfo" #endif +#ifndef READAHEAD_CONFIG_FILE +#define READAHEAD_CONFIG_FILE SYSCONFDIR "/readahead.conf" +#endif + /* Device information from the system */ struct device_info { char *device_number; @@ -110,6 +117,60 @@ static int get_device_info(const char *device_number, struct device_info *device return ret; } +static void config_entry_list_head_free(struct list_head *lh) { + struct config_entry *ce = containerof(lh, struct config_entry, list); + config_entry_free(ce); +} + +static int match_config(struct device_info *di, struct config_entry *ce) { +#define FIELD_CMP(field) \ + (ce->field == NULL || (di->field != NULL && strcmp(di->field, ce->field) == 0)) + + if (!FIELD_CMP(mountpoint)) + return 0; + + if (!FIELD_CMP(fstype)) + return 0; + + debug("Device matched with config\n"); + return 1; +#undef FIELD_CMP +} + +static int get_readahead(struct device_info *di, unsigned int *readahead) +{ + LIST_DECLARE(configs); + struct list_head *lh; + int ret = 0; + int default_ra = 0; + + if ((ret = parse_config(READAHEAD_CONFIG_FILE, &configs)) != 0) { + err("Failed to read configuration (%d)\n", ret); + goto out; + } + + list_for_each(lh, &configs) { + struct config_entry *ce = containerof(lh, struct config_entry, list); + if (ce->mountpoint == NULL && ce->fstype == NULL) { + default_ra = ce->readahead; + continue; + } + + if (match_config(di, ce)) { + *readahead = ce->readahead; + goto out; + } + } + + /* fallthrough */ + debug("Setting readahead to default %d\n", default_ra); + *readahead = default_ra; + +out: + list_free(&configs, config_entry_list_head_free); + return ret; +} + int main(int argc, char **argv, char **envp) { int ret = 0; @@ -134,7 +195,12 @@ int main(int argc, char **argv, char **envp) goto out; } - info("Setting %s readahead to 128\n", device.mountpoint); + if ((ret = get_readahead(&device, &readahead)) != 0) { + err("Failed to find readahead (%d)\n", ret); + goto out; + } + + info("Setting %s readahead to %u\n", device.mountpoint, readahead); log_close(); printf("%d\n", readahead); diff --git a/tools/nfs-readahead-udev/parser.y b/tools/nfs-readahead-udev/parser.y new file mode 100644 index 00000000..f6db05c4 --- /dev/null +++ b/tools/nfs-readahead-udev/parser.y @@ -0,0 +1,78 @@ +%{ +#include <stdio.h> +#include "parser.h" +#include "config_parser.h" +#include "log.h" + +extern int yylex(); +extern int yyparse(); +extern FILE *yyin; +void yyerror(const char *s); + +// This should be visible only to this file +extern struct config_entry *config_entry_new(void); + +struct config_entry *current; +%} + +%union { + int ival; +} + +%token <ival> INT +%token EQ +%token ENDL +%token DEFAULT +%token READAHEAD +%token END_CONFIG 0 + +%% +config: + lines +lines: + lines line | line | endls lines +line: + tokens endls { + struct config_entry *new = config_entry_new(); + list_add(&current->list, &new->list); + current = new; + } + + +tokens: + tokens token | token + +token: + default | pair + +default: + DEFAULT + +pair: + READAHEAD EQ INT { current->readahead = $3; } + +endls: + endls ENDL | ENDL + +%% +int parse_config(const char *filename, struct list_head *list) +{ + int ret; + + yyin = fopen(filename, "r"); + current = config_entry_new(); + list_add(list, &current->list); + + ret = yyparse(); + + /* The parser will create an empty entry that need to be eliminated */ + list_del(&current->list); + free(current); + fclose(yyin); + + return ret; +} + +void yyerror(const char *s) { + err("Failed to parse configuration: %s", s); +} diff --git a/tools/nfs-readahead-udev/readahead.conf b/tools/nfs-readahead-udev/readahead.conf new file mode 100644 index 00000000..988b30c7 --- /dev/null +++ b/tools/nfs-readahead-udev/readahead.conf @@ -0,0 +1 @@ +default readahead=128 diff --git a/tools/nfs-readahead-udev/scanner.l b/tools/nfs-readahead-udev/scanner.l new file mode 100644 index 00000000..d1ceb90b --- /dev/null +++ b/tools/nfs-readahead-udev/scanner.l @@ -0,0 +1,14 @@ +%{ +#include "parser.h" +#define yyterminate() return END_CONFIG +%} +%option noyywrap +%% +default { return DEFAULT; } +readahead { return READAHEAD; } +[ \t] ; +#[^\n]*\n { return ENDL; } +\n { return ENDL; } +[0-9]+ { yylval.ival = atoi(yytext); return INT; } += { return EQ; } +%%

[RFC,v2,5/7] readahead: create the configuration file

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