cregit-Linux how code gets into the kernel

Release 4.18 tools/perf/arch/x86/util/machine.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/types.h>
#include <linux/string.h>
#include <stdlib.h>

#include "../../util/machine.h"
#include "../../util/map.h"
#include "../../util/symbol.h"
#include "../../util/sane_ctype.h"

#include <symbol/kallsyms.h>

#if defined(__x86_64__)


struct extra_kernel_map_info {
	
int cnt;
	
int max_cnt;
	
struct extra_kernel_map *maps;
	
bool get_entry_trampolines;
	
u64 entry_trampoline;
};


static int add_extra_kernel_map(struct extra_kernel_map_info *mi, u64 start, u64 end, u64 pgoff, const char *name) { if (mi->cnt >= mi->max_cnt) { void *buf; size_t sz; mi->max_cnt = mi->max_cnt ? mi->max_cnt * 2 : 32; sz = sizeof(struct extra_kernel_map) * mi->max_cnt; buf = realloc(mi->maps, sz); if (!buf) return -1; mi->maps = buf; } mi->maps[mi->cnt].start = start; mi->maps[mi->cnt].end = end; mi->maps[mi->cnt].pgoff = pgoff; strlcpy(mi->maps[mi->cnt].name, name, KMAP_NAME_LEN); mi->cnt += 1; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Adrian Hunter164100.00%1100.00%
Total164100.00%1100.00%


static int find_extra_kernel_maps(void *arg, const char *name, char type, u64 start) { struct extra_kernel_map_info *mi = arg; if (!mi->entry_trampoline && kallsyms2elf_binding(type) == STB_GLOBAL && !strcmp(name, "_entry_trampoline")) { mi->entry_trampoline = start; return 0; } if (is_entry_trampoline(name)) { u64 end = start + page_size; return add_extra_kernel_map(mi, start, end, 0, name); } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Adrian Hunter94100.00%1100.00%
Total94100.00%1100.00%


int machine__create_extra_kernel_maps(struct machine *machine, struct dso *kernel) { struct extra_kernel_map_info mi = { .cnt = 0, }; char filename[PATH_MAX]; int ret; int i; machine__get_kallsyms_filename(machine, filename, PATH_MAX); if (symbol__restricted_filename(filename, "/proc/kallsyms")) return 0; ret = kallsyms__parse(filename, &mi, find_extra_kernel_maps); if (ret) goto out_free; if (!mi.entry_trampoline) goto out_free; for (i = 0; i < mi.cnt; i++) { struct extra_kernel_map *xm = &mi.maps[i]; xm->pgoff = mi.entry_trampoline; ret = machine__create_extra_kernel_map(machine, kernel, xm); if (ret) goto out_free; } machine->trampolines_mapped = mi.cnt; out_free: free(mi.maps); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Adrian Hunter164100.00%1100.00%
Total164100.00%1100.00%

#endif

Overall Contributors

PersonTokensPropCommitsCommitProp
Adrian Hunter477100.00%1100.00%
Total477100.00%1100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.